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Thread: 650b Mojo

  1. #1
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    650b Mojo

    I got my first ride with 650b tires front and rear on my 2 year old Mojo. Thanks again Kirk Pacenti for bringing 650b wheel size and your very high quality tires to mountain bikes.

    Iíve run 6 months with the AM trail tread neo-moto with 26x2.3 size tires in the rear. The 650b front improved the ride very noticeably. Adding the 650b rear was a more subtle additional improvement, also noticeably smoother and easier to roll over rocks.

    The Pacenti quas-moto 2.0 tire fits the rear of the Mojo with at least ľ inch clearance, not enough for mud but enough for dry conditions. I had to put a shim the thickness of a quarter dollar coin under my PUSHíd Ď02 Vanilla RC bottom-bumper to limit travel and avoid rubbing the seat tube at bottom out. So the rear wheel travel is ľ inch less at only 5.25 inch travel now and uses the bottom bumper more on the occasions of full travel landing some of the jumps on my local trail. (PUSH makes shims for the air shocks they service if you decide to shorten travel. I donít know of a way to do it yourself for air shocks.)

    Overall the ride is smoother including the small travel loss. I actually reduced spring preload since I had added a turn or more to compensate for the 650b front only previously slackening the frame angles. I still have to tweak the damping and preload to fully optimize the taller wheel size.

    The quasi-moto hooks up surprisingly well for itís short and widely spaced knobs. It clearly rolled easier, smoother, and braked and cornered much better than the 26x2.3 Kenda Small Block 8ís I had been riding on the 26 rear wheel. Braking and corner grip is very close to the 26x2.3 Nevegal or Rampage tires, and of course the quasi-moto rolls much smoother and easier. The only fear is the knobs of the quasi-moto donít protrude wider than the side wall like the neo-motos using the same casing, so the sidewalls are rather unprotected from scrapes when brushing up against rock faces (Kirk it looks like the same knobs could be moved slightly outboard for better sidewall protection with no loss, if not greater cornering traction.)

    Gear ratios were all 5 - 6% higher than 26 inch rear wheel with the bigger 650b diameter. Itís noticeable and I had to find different gears than I was used to on the local trail I helped to build about 10 years ago and Iíve ridden at least 1500 times. The higher gear ratio and easier rolling inspired a faster pace, and the faster pace improved momentum and added up to being easier to do steady climbs faster. Steep climbs had great grip even in loose dirt and the slightly higher granny low made it easier to maintain traction.

    The adding the rear to match the axle height of the 650b front wheel returned the handling to the superb handling balance of the stock Mojo but much better pedaling clearance, curing my only minor disappointment with the stock Mojo. Having a low bottom bracket height at 13 inches, the Mojo with 26 inch wheels has occasionally poor pedaling clearance on rough trail. Using a 650bx2.3 neo-moto in front only with a 26x2.3 in back got the BB up to a decent 13.5 with a 140mm fork. With the 650b in back the BB is up to 13.65 inches with a 140 travel fork, ideal for a trail bike with 5.5 inch travel. Raising my Nixon 130-160 up to 160 makes 14 inch BB. I finally had a ride on the Mojo with no pedal strikes on my local favorite singletrack loop with rocky and gravelly fast fireroad downhill for the last mile.

    I ran with a tube in the rear using a temporary test wheel I built from my junk undersized Velocity and poor quality Hope Pro2 hub I canít stand for itís alarm-clock loud ratcheting and slow for 24-count engagement and noticeably high friction. I managed to pinch flat on some g-out stream crossings or jump landing in the fast rocky downhill at the end of the ride. Iíve been running Stanís tubeless convert for a couple years and so rarely have flats it was really disappointing to use tubes. Tubes require higher pressures than I like anywhere except where it so rocky every where that high pressures are required to avoid wheel damage and pressures higher than 32 psi blow Stanís converted tubeless tires off the rim. I look forward to running safer UST bead 650b tires tubeless in all conditions.

    Hereís some pictures:
    Attached Images Attached Images

  2. #2
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    Thanks for the report Derby - that thing looks fantastic!

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    Very interesting stuff. What fork is that? Is your rear shock the recommended stock i2i and stroke? I'm game when some proper UST or TR tires comes out.

  4. #4
    NedwannaB
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    Familiar mountain......

    Quote Originally Posted by derby
    Here's some pictures:
    .....in backround of first pic! South side of CC or WWheel @ Tamarancho. Close?.....

  5. #5
    Mr.650b - Mr.27-5
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    Derby,

    Have you shown this to the boys and girls at Ibis?

    The beauty of that design is that with a slight drop out modification they could produce a 650B compatible bike with relative ease.
    If you like my products and services tell everyone. If you don't, tell me - kirk(at)pacenticycledesign.com

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    Yeah, give them a hint. I already hinted at this on the other thread in the Ibis forum. They would probably have to redesign the swingarm for more tire clearance though- it is very close with a 650B/2.0 tire which is pretty skinny.

  7. #7
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    I had a strong feeling the Quasi would be a sweet tire.
    Cash along with the fear of sidewall damage keep me from going full 650b on my Rush. I'm glad your enjoying the full 650b experience on your Mojo. I really hope the quasi holds up to your trails - then you can go tubeless which as we know is the only way to go.

    I had heard the Hope Pro2 hubs were very nice except for the noise. Price and engagement are good at least, but you are saying even the engagement is not good? What would you use instead? I did not like the CK hub I had 11 years ago...and pricey.

  8. #8
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    Quote Originally Posted by Flyer
    Very interesting stuff. What fork is that? Is your rear shock the recommended stock i2i and stroke? I'm game when some proper UST or TR tires comes out.
    Fork is a discontinued '07 Nixon Elite RWDT 130-160 coil (Manitou still makes an í08 air version with very good reviews). It's kind of flexy compared to a Pike at 140mm travel or any 36 longer travel fork, but light weight and great damping well matching the PUSH'd '02 Vanilla RC. The RC is a 7.875x2.25 with spacer under the bottom bumper PUSH made to limit travel to 2.0 for 5.5 inch stock measured wheel travel without hitting the seat post. I had to piggyback another spacer to limit wheel travel to 5.25 for the bottom travel clearance for the taller 650b.

    I hear you on the UST/TR need for use in harsher conditions needing higher pressures than Stan's converted non-tubeless can tolerate safely - that goes for any size wheel. Hopefully Kirk can get them made up.

  9. #9
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    Quote Originally Posted by Kirk Pacenti
    Derby,

    Have you shown this to the boys and girls at Ibis?

    The beauty of that design is that with a slight drop out modification they could produce a 650B compatible bike with relative ease.
    In Ibis forum I posted a link to this post.

    Yes 6 months ago I asked Hans for modular dropouts for many uses, such as wheel sizes, BB height adjust, singlespeed, etc. The retooling for carbon fiber manufacturing is very costly and it didn't seem very feasible. I don't think it would take much to develop modular dropouts, using the same fitment points and change the dropouts to stubs that had bolt on brake mount and drop outs. I've considered designing some for the aftermarket myself. I hope it happens, but they probably have other priorities with greater market demand to cover first.

  10. #10
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    Quote Originally Posted by JMac47
    .....in backround of first pic! South side of CC or WWheel @ Tamarancho. Close?.....
    WW! Bingo!

  11. #11
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    Quote Originally Posted by yogiprophet
    I had a strong feeling the Quasi would be a sweet tire.
    Cash along with the fear of sidewall damage keep me from going full 650b on my Rush. I'm glad your enjoying the full 650b experience on your Mojo. I really hope the quasi holds up to your trails - then you can go tubeless which as we know is the only way to go.

    I had heard the Hope Pro2 hubs were very nice except for the noise. Price and engagement are good at least, but you are saying even the engagement is not good? What would you use instead? I did not like the CK hub I had 11 years ago...and pricey.
    About my dislike of the Hope Pro2, my opinion I think irritated someone about a year ago I won't mention who started a little hate-derby cult that still stalks and harasses a few of my posted opinions now and then, flaming lies and twisting words about my opinions. I was very disappointed at the Pro2's rear hub large backwards step in performance and frustrated with the lack of ease of maintenance compared to the earlier Hope Bulb model I used for many years with no issues having quick and quiet 32 point engagement. 24 point engagement is normally not very slow in engagement speed. But the Pro2ís 24 point engagement is slow because it has teeth which are saw-tooth shaped and the pawls backup or hesitate to seat into the teeth after engaging. It really engages about as quickly as a good 18 point hub, which is OK for downhill and higher gears but slow for middle ring and very slow for granny gear use. It required much brute force to pull apart the freewheel to maintain lube as I found out trying to quiet down the alarm-clock noisy ratcheting which is obnoxious to me and some friends who commented on the noise. The seal doesnít retain lube (Hope used a minimal amount of the stickiest lube I've ever seen in the new hub to avoid bleeding out all over the spokes, Phil's Tenacious Oil is nothing compared.) The hub is impossible to quiet to close to a normal noise. The unusual stiff pawl spring design produces noticeably more freewheel friction than most hubs, minor performance loss, but like a very lightly dragging brake. I won't ride it except like now for a short test before committing to buying a quality hub to build a wheel for long term use.

    I like any other hub better. My favorite is Hadley's. They are 72 point quick engaging, very quiet, easy to maintain, great customer help, not heavy but not extra light either, convertable from 5mmQR to 10 or 12mm solid through axle bolt on. Possibly Maxle compatible, but I'm not sure. Hadelys are about 50% more expensive comparing list prices than a Pro2, but less than CK.

    The new XT and XTR hubs are 32 point, and getting very good reviews too, there are converters from spline to 6 bolt rotor mounts available.

  12. #12
    NedwannaB
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    Thought so....

    Quote Originally Posted by derby
    WW! Bingo!
    We were accross from Pine Mtn. on Bolinas Ridge Sunday. What a perfect day, little warm but a breeze from the fog bank holding one ridge over above Stinson.

    I have a couple q's re: 650's. Check your PM.

    Thanks Jmac

  13. #13
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    Quote Originally Posted by derby
    Fork is a discontinued '07 Nixon Elite RWDT 130-160 coil (Manitou still makes an í08 air version with very good reviews). It's kind of flexy compared to a Pike at 140mm travel or any 36 longer travel fork, but light weight and great damping well matching the PUSH'd '02 Vanilla RC. The RC is a 7.875x2.25 with spacer under the bottom bumper PUSH made to limit travel to 2.0 for 5.5 inch stock measured wheel travel without hitting the seat post. I had to piggyback another spacer to limit wheel travel to 5.25 for the bottom travel clearance for the taller 650b.

    I hear you on the UST/TR need for use in harsher conditions needing higher pressures than Stan's converted non-tubeless can tolerate safely - that goes for any size wheel. Hopefully Kirk can get them made up.
    Thanks for the info! The tires are my main concern. I have seen quite a few of the regular tires burp badly enough to cause crashes on hard and fast turns. I used to do it myself till I saw my buddy go down hard in front of me. I consider it a major safety issue though many will probably think I'm a big ssisy for thinkig that way. That's fine- I'm happy with my sometimes paranoid ways when it comes to tires.

    Good to see you try this, Derby. I think the 650B wheelsize has huge potential but it really needs a couple of powerful catalysts- another 650B fork (from Fox or RS), one big (Specy/Trek) or 3-4 smaller manufacturers to jump on board with frames, and...well, that's about it. The rest (tires, rims, other frame manufacturers, etc.) will be a flurry of activity even in a year of slow bike sales.

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    Cool, thanks Derb I'm at 5/9 maybe a little short for a 29er, (long torso, short little legs) but this should be perfect for me to try. As far as the travel limiting on the air shock could I just run enough pressure to keep it from ever really going full travel maybe @ 8mm sag ?
    Thanks again.

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    Yes 6 months ago I asked Hans for modular dropouts for many uses, such as wheel sizes, BB height adjust, singlespeed, etc. The retooling for carbon fiber manufacturing is very costly and it didn't seem very feasible. I don't think it would take much to develop modular dropouts, using the same fitment points and change the dropouts to stubs that had bolt on brake mount and drop outs. I've considered designing some for the aftermarket myself. I hope it happens, but they probably have other priorities with greater market demand to cover first.
    Hmm, what if Ibis introduce the Tranny swap rear triangle concept to the Mojo? or they could just redesign the rear triangle and start selling em?
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  16. #16
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    Quote Originally Posted by glovemtb
    As far as the travel limiting on the air shock could I just run enough pressure to keep it from ever really going full travel maybe @ 8mm sag ?
    Thanks again.
    I wouldn't. You'd be limited in sag adjustment and screw up handling, and the tire might still scrape and damage the seat tube. A bike is not designed to take even a light hit to the back of the seat tube. It could be very dangerous if the frame collapsed at the same time you bottom travel.

    PUSH will do that shaft travel reduction at no extra cost when doing the minimum oil change service or any enhanced performance tune.

  17. #17
    Mr.650b - Mr.27-5
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    Quote Originally Posted by glovemtb
    Cool, thanks Derb I'm at 5/9 maybe a little short for a 29er, (long torso, short little legs) but this should be perfect for me to try. As far as the travel limiting on the air shock could I just run enough pressure to keep it from ever really going full travel maybe @ 8mm sag ?
    Thanks again.

    I will second Derby's thoughts here. Reducing the travel by upping air pressure in the shock is not a good idea. even if it prevented the tire from striking the ST, the ride would be altered considerably and certainly for the worse.

    Fwiw, I have been riding an Ibex Atlas (kinda like a Heckler) with 650B wheels installed for some time with good results. I have been running the shock on the soft side and with no modifications / limitations to the travel made. I have yet to get the tire to strike the ST. YMMV.
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  18. #18
    mnt bike laws of physics
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    Quote Originally Posted by derby
    I like any other hub better. My favorite is Hadley's. They are 72 point quick engaging, very quiet, easy to maintain, great customer help, not heavy but not extra light either, convertable from 5mmQR to 10 or 12mm solid through axle bolt on. Possibly Maxle compatible, but I'm not sure. Hadelys are about 50% more expensive comparing list prices than a Pro2, but less than CK.

    The new XT and XTR hubs are 32 point, and getting very good reviews too, there are converters from spline to 6 bolt rotor mounts available.
    Yea, dieselcruiserhead was talking about his new Hadleys. I think they now have 3 offset pawls for 108 point Engagement. Pretty serious huh? And they are not very loud. They make a 10mm aluminum QR through axle just like DT Swiss. Do you know if they do the same for the front with a 9mm?

  19. #19
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    Quote Originally Posted by yogiprophet
    Yea, dieselcruiserhead was talking about his new Hadleys. I think they now have 3 offset pawls for 108 point Engagement. Pretty serious huh? And they are not very loud. They make a 10mm aluminum QR through axle just like DT Swiss. Do you know if they do the same for the front with a 9mm?
    Hadley used to do 108 point engagement I had read about while doing research before buying my rear hub last fall, but now "only" 72 point. I don't know about the Hadley front hub. I'll buy one next time I need a front hub, but I have a Hope Bulb front hub (and a spare similar but slightly more flexy designed Pro2) now which has held up with a very slow rate of bearing wear compared to many other front hubs I've used previously.

  20. #20
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    This is very interesting.

    I have been debating if I should get a 29er to complement my Mojo.

    But the 29ers I have tried did not fully satisfy me, at only 5'10"/150lbs. But all my friends are moving to the 29er bandwagon, which appear to be a good fit for our local Texas trails. But they are bigger/taller guys.

    Derby, are you seriously considering this 650b conversion permanently?

    I am almost tempted to give it a try as a permanent setup.

    I would get:
    - WB Fluid-650b 130 (Can I stay with my 08 Talas 32 RLC fork instead?)
    - QuasiMoto Tires (The mud clearance is a non-issue for me)
    - NoTubes wheelset
    - Get my Fox RP23 tuned and limit travel as you recommended to 5.25"
    Last edited by flafonta; 08-07-2008 at 08:41 AM.

  21. #21
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    Derb
    I wouldn't. You'd be limited in sag adjustment and screw up handling, and the tire might still scrape and damage the seat tube. A bike is not designed to take even a light hit to the back of the seat tube. It could be very dangerous if the frame collapsed at the same time you bottom travel.

    PUSH will do that shaft travel reduction at no extra cost when doing the minimum oil change service or any enhanced performance tune.
    Kirk Pacenti
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    I will second Derby's thoughts here. Reducing the travel by upping air pressure in the shock is not a good idea. even if it prevented the tire from striking the ST, the ride would be altered considerably and certainly for the worse.
    Ok I'm excited about trying this easy as heck conversion for My Moj SL and pretty sure I would never go back to 26". But, I'm running RPL rear shock. Push does not work on them. I have not talked to Darren, but Jim said no.
    I would have to find someone to do the limit setting for me.
    You guys have any ideas on that ?

    Of course I have an RP23 medium compression tune sitting around I could send them.
    (Running a Talas in front.)
    So on to Wheels and Tires.

  22. #22
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    I need to test more conditions to verify exactly want the shock shaft travel limit shim should be. I did bottom travel on my first ride a few times and slightly scraped some tape I’ve got on the back of the seat tube. I’ve been too busy at work to ride more since that first test ride last weekend - hopefully I’ll be riding tonight.

    Another thing to consider is using a 650b wheel would very likely void your Mojo’s 3 year warranty, at least for the swingarm. Ibis is very reasonable but 650b is clearly not a stock option.

    I’ve got a proposal in with Ibis to finance a short run of reliable and warranteed 650b swing arms. If I or someone can contract that, it could be feasible to have them available in 3 – 6 months. But as you know the wait time can be much longer.

    Going to 650b front only is about 3/4’s of the noticeable gain in rolling and handling performance using a good 26 inch rear tire. All you need is a new front wheel and tire if using Fox, most RS and Manitou forks (I haven’t heard much about Marzocchi forks).

    Full 650b Mojo is very nice. My AM style of riding really needs the more durable neo-moto to fit in the rear and to reasonably clear mud also. I’m not going to be satisfied until I’m on a dw-link bike that fits them front and rear, hopefully the Mojo.

  23. #23
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    We should do a poll here on how many riders are willing and able to buy the new swingarm. I know I'm in but only with a full 650B setup so I'd invest in the new swingarm. I wonder how many they have to order for a single batch.

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    derby,

    A 2006 fox talas doesn't need a spacer to limit travel?

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    We should do a poll here on how many riders are willing and able to buy the new swingarm. I know I'm in but only with a full 650B setup so I'd invest in the new swingarm. I wonder how many they have to order for a single batch.
    New Moj toys ? I'm all in.

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    Quote Originally Posted by BlueMountain
    We should do a poll here on how many riders are willing and able to buy the new swingarm. I know I'm in but only with a full 650B setup so I'd invest in the new swingarm. I wonder how many they have to order for a single batch.
    Count me in as well.

  27. #27
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    Count me in, i'm willing and able to buy the 650b swingarm. I'm all over the 650b movement.

  28. #28
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    So can someone tell me what is 650b? is it a 29er or a 69er?
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  29. #29
    Mr.650b - Mr.27-5
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    Quote Originally Posted by VTmojo
    Count me in, i'm willing and able to buy the 650b swingarm. I'm all over the 650b movement.

    Heck, if they do it, I will buy the whole frame!
    If you like my products and services tell everyone. If you don't, tell me - kirk(at)pacenticycledesign.com

  30. #30
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    It's neither. It's a rim size inbetween 26in and a 29er.

    Here's some links to more info:
    - What is a 650B Mountain Bike and Why Would I Want One?
    - I know there is a Sticky, but WHAT IS 650B???
    - Wanted: Sticky for basic 96er, 650b, etc information

    jw


    Quote Originally Posted by wheelhot
    So can someone tell me what is 650b? is it a 29er or a 69er?
    -

    "And single-speeding 29ers are mountain biking's equivalent of Scientologists..." - Captain Dondo

  31. #31
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    So can someone tell me what is 650b? is it a 29er or a 69er?
    My best guess its it is the correct tire size for guys sized 5'8 or so to 6ft. Above that, 29er. Under that...well, you know.
    I will probably give it a try in a couple of weeks and do a review for a guy of 5'9".
    Edit, the quasi also fits the newer painted (not just the clearcoat) SLs. You can even get a Neo Moto back there if you grind the side lugs about 2-4 mm.
    Quasi has plenty of clearance just as on Derb's test for Moj classic.
    Last edited by ghawk; 08-19-2008 at 02:17 PM.

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    I'm in

    Everybody in our club is going 29. I can see that because of out type of terrain we have. I'm going 650 upfront for now, and will buy a new swing arm if and when it comes out. SO count me in.

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    Aaah, thanks
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  34. #34
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    That's impressive derby!
    I so much wish quasi would fit in the rear of my LT2...
    But there's no way it will because of the FD cable stop.

  35. #35
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    Mojo 650b swingarm

    I'm in as well. I need this bike for next year's Leadville 100, so tell them to get on it!

  36. #36
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    I'm in

    I already have 650b on the front of my Mojo and would love to have it on the rear.

    By the way, I'm 5'5" and 650b works great for me on a small frame.

    I just got back from Moab and while there I fell further in love with 650b.

    Mojo + 650b + Shuttle to Burro Pass = one sweet ride.

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    I'll buy one. I'm going build a 650b front wheel this winter and see how it goes from there.
    A bicycle will take you to fantastic places....if you let it.


    Ibis fan since '08 now rolling on the big wheeled Ripley.

  38. #38
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    Derby,

    Have you had a chance to hook up with Hans since Interbike? I stopped by to say hello to the gang at Ibis, but they were pretty busy and I didn't want to bother them with "hard sell" for 650B wheels.

    Cheers,

    KP
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    I know most of you guys know that several of us are allready running 650b Mojo SLs here on the front range of Colorado.
    My setup is stans ztr/neos front/back (back cut down ethier side 2 sets of side lugs to 1/2 size [about 3mm high], run tubeless with about 4mm swingarm clearance. (Thanks to Derb, glove, Kirk, Stan, Mom, FDIC (new 250,000 limit), etc.)
    http://www.exacteditions.com/exact/b.../511/3616/3/28
    How about those eyes
    Note, imho I do not think Ibis would void the warrantee unless you do something really stupid, like not making sure your rear shock will not bottom or keep wheel tru.

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    I'll be testing my new 650b front wheel on my SL tomorrow (weather permitting). The wheel seems to be a perfict size for a mt'n bike. I'm surprised more builders haven't offered this size.

    Know, if we could only persuade the people at Ibis to build a 650B swingarm.

    David

  41. #41
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    ghawk, did you modify your rear shock?

    I have been running a 650b front wheel (ZTR w/ Neo) on my Mojo for a couple of months now and absolutely love it. It is the best modification I have ever made on a bike. I would love to go full 650b, but I have read from posts by Derby that doing so requires the travel to be shortened. What did you do?

  42. #42
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    Quote Originally Posted by tortfeasor
    I have been running a 650b front wheel (ZTR w/ Neo) on my Mojo for a couple of months now and absolutely love it. It is the best modification I have ever made on a bike. I would love to go full 650b, but I have read from posts by Derby that doing so requires the travel to be shortened. What did you do?
    Nope, I did Derbs recommended test of letting all the air out of the shock to see the wheel would contact the seat tube. (You can do it with your front wheel with a bit of creativity and an old rear wheel skewer that you don't mind if it gets bent.)
    Since it just barely touched the seattube. I then inflated to 50 lbs and tried it again. Bouncing hard on it I could just barely get contact if at all. So, then nothing at 75psi. So, seeing as how I ride at xcountry sag height and at 170 lbs (body weight important) I figured I could never with rp23 or rpl make contact running 12-13mm sag I would never hit it at my normal pressure. Sure enough. I even run a line cable tie (see moj setup instructions pdf) and it never even hits that, thus I knew I would be fine.
    But, remember this is an SL and Derb is running Moj classic.
    If you like the ole rule of thumb of running your shocks so you bottom out every once and awhile then as Derb mentioned this can cause catastrophic failure to the carbon frame if you shall we say.. buzz it a bit much. So, I am not recommending doing this without shock mods.
    Last edited by ghawk; 10-08-2008 at 05:29 AM.

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    In The Final Analysis Rear Neo Lug Sizing

    Quote Originally Posted by ghawk
    I know most of you guys know that several of us are already running 650b Mojo SLs here on the front range of Colorado.
    My setup is stans ztr/neos front/back (back cut down either side 2 sets of side lugs to 1/2 size [about 3mm high], run tubeless with about 4mm swingarm clearance. (Thanks to Derb, glove, Kirk, Stan, Mom, FDIC (new 250,000 limit), etc.)
    http://www.exacteditions.com/exact/b.../511/3616/3/28
    How about those eyes
    Note, imho I do not think Ibis would void the warrantee unless you do something really stupid, like not making sure your rear shock will not bottom or keep wheel tru.
    What has worked best that I can say for a Moj SL:
    Stans ZTR rims, Neo Motos Front and Back (Do your Fork research. I run F/Talas.)
    Helicopter tape the swing-arm where you may get contact of the rear wheel.
    After cutting the above mentioned 2 sets of side lugs (on either side) down they now measure: 3mm-3.5mm. These lugs would normally be 5-6mm. I did not do a good length cut-down initially and as the tire carcass expanded I had to trim 2 times! (It was a simple procedure if done carefully enough, I used a 1 sided Retractable Blade Knife WITH Thick gloves to cut 3/4 thru the lugs and then after getting all of them prepped, finish the cut with a set of wire cutters - with wheel on.)
    My final clearance is a closest contact point (2 sets of outside lugs) 4.5 to 4mm. Center I get at the very least, 5mm.
    Note: I sanded the tire slightly but this had little effect maybe a couple of mm at most.
    I am also another one running ghetto tubeless with these tires with great success over time. With this side lug size I still have plenty of grip at about 26-28 pounds pressure depending on terrain.
    Sounds like allot of trouble, but with every outing I appreciate rolling on a right size wheel and tire. An hour or so of tire work seems like a small price. (Or you can just go quasi on back. Remember you will give up some all mountain feel of Moj.)
    Also, be sure and get a spoke tension meter (should have one anyway) to keep wheel rolling round and carry a spoke tool.
    No shock mods here as I never use last inch of travel for my type of riding. Light Endurance Mountain Biking at 165 lbs. But as mentioned as a rule the mod should be done. As someone said before you notice that small difference with every tire revolution.
    Last edited by glovemtb; 10-11-2008 at 06:47 AM.

  44. #44
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    Quote Originally Posted by glovemtb
    What has worked best that I can say for a Moj SL:
    Stans ZTR rims, Neo Motos Front and Back (Do your Fork research. I run F/Talas.)
    Helicopter tape the swing-arm where you may get contact of the rear wheel.
    After cutting the above mentioned 2 sets of side lugs (on either side) down they now measure: 3mm-3.5mm. These lugs would normally be 5-6mm. I did not do a good length cut-down initially and as the tire carcass expanded I had to trim 2 times! (It was a simple procedure if done carefully enough, I used a 1 sided Retractable Blade Knife WITH Thick gloves to cut 3/4 thru the lugs and then after getting all of them prepped, finish the cut with a set of wire cutters - with wheel on.)
    My final clearance is a closest contact point (2 sets of outside lugs) 4.5 to 4mm. Center I get 5mm.

    No shock mods here as I never use last inch of travel for my type of riding. Light Endurance Mountain Biking at 165 lbs. But as mentioned as a rule the mod should be done.
    I confirmed the above for myself today. I should have done this long ago.

    Today I visited Paragon Bikes in San Anselmo, CA today, an Ibis dealer with 4 SLs and 1 clear standard Mojo in stock. I verified with my own wheel that the 650b Pacenti Quasi-moto XC tire fits both the SL and standard clear Mojo with about 8 to 10mm clearance, and the Neo-moto AM tire would also fit with about 4 - 6mm except the side knobs would need to be trimmed about 3mm shorter for such clearance all around.

    Ibis mailed that the size has never changed. So I guess I have an irregular because mine is about 4-5mm shorter in wheel clearance with the same stay length. I checked the chain stay length is the same 16 7/8 inch. These were frame only, but I’ve heard from a reliable source that the BB height measures about 1/8 inch higher than my early production, so I’m guessing the seat tube clearance is normally more than I have as well.

    I didn’t check seat tube without air pressure in the shock, but I think by the test of glovemtb a 1/8 to ľ inch thick rubber o-ring could be put inside the air can of an RP23 or other air shock to limit bottom travel in the case of failure to hold air. A coil shock needs to be travel limited by 1/8 inch thick washer secured under the bottom travel bumper.

    Thanks glovemtb and ghawk for testing the newer models. I still want Ibis to add about 4mm in chainstay length with a special 650b swingarm to have plenty of mud clearance with the 2.3 tire size.
    Last edited by derby; 10-08-2008 at 06:38 PM.

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    Ibis emai mailed that the size has never changed. So I guess I have an irregular because mine is about 4-5mm shorter in wheel clearance with the same stay length. I checked the chain stay length is the same 16 7/8 inch. These were frame only, but I’ve heard from a reliable source that the BB height measures about 1/8 inch higher than my early production, so I’m guessing the seat tube clearance is normally more than I have as well.
    I think they need to send you a new standard swingarm. Esp since you will be running 650bs.
    Something changed since the early days. I have talked to too many guys that had swingarm failures for something not to have changed. All I can guess is the layup enhancements they made to enhance the bb area are it. Btw, I have to tru my rear wheel as my dog sat on it's spokes sideways, ouch.

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    Just to be clear: If I use the Quasi-Moto in the rear, it should fit without any modifications to the tire, right?

    And then I can put the Neo-Moto in front with my Talas fork, again with no tire mods?

  47. #47
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    Quote Originally Posted by flafonta
    Just to be clear: If I use the Quasi-Moto in the rear, it should fit without any modifications to the tire, right?

    And then I can put the Neo-Moto in front with my Talas fork, again with no tire mods?
    I saw OK mud clearance for the quasi-moto fitting mine in new Mojos today, no problem for dry conditions. Neo-moto rear would be tight and probably needs outer knobs trimmed down.

    Quasi-moto in front has no potential clearance problems, plenty of room in a Fox 32/140 fork. A new Neo-moto can lightly rub the crown of the Fox 32 fork at bottom travel if the spring fails. It is unusual riders ever utilize the deepest 1 inch of travel of those forks without air or coil spring fork failure or custom modification of the fork to gain full travel. Test your fork travel by using a zip-tie around one leg and compressing as hard as possible landing a jump or whatever you do hardest on the fork. And later let the air out or remove the coil spring cap and compress the fork to see where mechanical bottom of travel is. You will probably find that you never use the deepest 1 inch of travel while riding.
    Last edited by derby; 10-08-2008 at 07:05 PM.

  48. #48
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    ghawk,

    Are you running an rp23?

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    No RPL please see previous post

    Quote Originally Posted by tortfeasor
    Are you running an rp23?
    No, I needed a firmer, higher ride most of the time so I added an Fox RPL.(same size as rp23, with propedal and open but also lockout sitting really high in stroke.
    I beleive what I mentioned above also applies to the rp23 if you do similar testing at the different pressures mentioned. You have to almost totally bottom shock (within 10mm or so) to make tire contact with sl swingarm with the previous mentioned setup. Proceed carefully so you feel safe with what you are doing.

  50. #50
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    Thanks for the input.

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    2mm (1/16 in) limited shock travel

    Quote Originally Posted by ghawk
    Proceed carefully so you feel safe with what you are doing.
    650b use with the Mojo is experimental. The Mojo shock's bottom travel should be limited by 2mm.

    I got a new standard Mojo clear finish swingarm and found my early production was completely 3/16 inch shorter due to dropout placement.

    I measured bottom travel seat tube clearance with coil removed using shims under the bottom bumper. And while I was using two 1/16th inch (2mm) washers for shims previously. Now I need just one shim to have plenty of seat tube clearance. Without the shim the Quasi-moto lightly brushes the seat tube.

    I can bottom my coil shock travel when landing jumps. I was never able to bottom an RP23 with my ride style. If you never bottom travel you should be fine without limiting travel.

    As ghawk says: “Proceed carefully so you feel safe with what you are doing.”
    Last edited by derby; 10-12-2008 at 09:43 AM.

  52. #52
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    Quote Originally Posted by ghawk
    I think they need to send you a new standard swingarm. Esp since you will be running 650bs.
    Something changed since the early days. I have talked to too many guys that had swingarm failures for something not to have changed. All I can guess is the layup enhancements they made to enhance the bb area are it. Btw, I have to tru my rear wheel as my dog sat on it's spokes sideways, ouch.
    That must be one big dog!.

    Ibis sent me a new standard swingarm. I offered to pay because mine was fine but I couldn't run 650b quasi without off setting the dish by 3mm to the drive side, and the slightly off balance was really beginning to bug me. It felt like I had a soft tire turning left. The dropouts on my original swingarm were mounted 3/16 inch closer in to the pivots, everything else looked the same but I gained even more clearance that that measurement. I asked for an invoice but didn’t receive one. I guess I’m another example that Ibis is over the top in quality customer support. And apparently they are not afraid of 650b use on the Mojo.

    I trued up my rear wheel dish and now the Mojo easily clears the Pacenti 650bx2.0 Quasi-moto tire with good mud clearance. I’ll probably go back to a better mud tire on a 26 inch rim when it gets muddy here this winter.

    I've now got a used 650bx2.3 Neo-moto mounted with tight clearances, a new one could squeeze fit too. But I had to snip down about 6 or 7 irregularly tall knobs from the second row away from center on the drive side, and in the granny I'm getting a little front derailleur rub when topped out. But I'm normally sagged enough to clear when in the granny but hear the der buzz the outer knobs a little while crawling up and bouncing over larger roots and rocks.

    Edit: On a second ride with the Neo-Moto in the swingarm there was not any derailleur or other tire rub. So I've got the derailleur adjustment just right to clear the knobs in the granny. It's nice to have the greater traction compared to the Quasi-moto. I'm looking forward to a 2.1 Neo-Moto to have easy clearance and enough for ride-able muddy days and muddy stream crossings.

    The Neo-moto easily clears the seat tube at bottom travel using a 2mm (1/16 inch) washer as a spacer. An air shock user could possibly add a 1/8 inch o-ring inside the air can to mechanically limit travel if it did fail and loose air pressure or a rider was bottoming travel.

    We still need a Mojo swingarm that is 3/8 inch longer for easy clearance with no modifications for up to 2.4 size 650b tires.
    Last edited by derby; 10-22-2008 at 08:38 AM.

  53. #53
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    We still need a Mojo swingarm that is 3/8 inch longer for easy clearance with no modifications for up to 2.4 size 650b tires.
    Yup, Tranny like rear triangle, able to be changed, but that maybe will compromise the Mojo strength. Maybe they could offer a 650b swingarm for BTO?
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  54. #54
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    Any word on the 650B rear triangle? I'm ready to pull the trigger on a Mojo SL if they can get r done!

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    another successful 650b implementation on the mojo

    I've posted here before...just wanted to provide an update.
    I've run 650b front and rear on my mojo sl with no clearance issues.
    rp23 or dt swiss shock
    stans 650b rims (on kings) with neo moto and quasi moto

    all variations have been quite workable on the trail. though before heading out on an all-day (or, at least as long as we could hang on) ride for my brother's birthday last friday, I did swap back to my 26" rear wheel anticipating that I may need some additional mud clearance. turns out I didn't need it...it was much drier in santa cruz than I anticipated...but the point is that even with the quasi in back, it 'clears' just fine, but there's not enough clearance to be confident that a really muddy day wouldn't cause some headaches and harm to the rear triangle.

    I do really dig the way the bike works with 650b front and rear...but as I've posted before, I feel like 75% of the benefit of 650b can be had with a front wheel-only implementation. Especially when you run a neo moto up front...it is easily one of the best all around tires I've ever ridden...I'm very impressed with the tire.

    swapping back and forth does cause geometry issues...but that's all personal choice.
    I'm one of the odd birds that prefers my mojo with a 130mm fork (fox 130 xtt). to compensate, I snagged a 100/120/140 talas from my friends at fox (along with a tuned rp23 to replace the dt swiss the frame came with)...I ran the fork in the 120 setting most of the day (technical singletrack, lots of steep, short climbs and descents)...with the 650b front / 26" rear (running a conti vertical pro on the rear), the geometry came out much like running my 130mm on 26/26 or 650b/650b.

    Overall, a very satisfying setup!

  56. #56
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    The only progress from Ibis on a longer chainstay for 650b that I'm aware of is that they have estimated the tooling cost for the longer dropouts and brake mount. They are busy producing projects already in the pipeline for over a year. I think it will come eventually.

    Your personal emails to Scot or Hans @Ibis may help them see there are numbers of Mojo riders ready to buy such a swingarm.

    I don't like the tight clearance with the 2.3 Neomotos, but on a very true rim I have had no real clearance issues with the Neomotos after snipping a few irregularly tall knobs shorter with a nail puller/ wire cutter priers. I've done a few very muddy rides in Northern California and more sandy and gravely mud in Utah without clearance problems.

    I added thin plastic tape to the swingarm yoke where the tire knobs are close and after a few months of Neo-Moto use I just replaced the tape a couple days ago. The old tape had worn through where the side knobs, having only 3 to 4 mm clearance, brushed them occasionally from flex and mud friction but the finish paint of the swingarm was barely marred. This showed me that the Mojo has extraordinarily minimal lateral flex in the swingarm. Twisting or torsion flex in the swingarm is only a little better than average compared to other bikes with this travel with the original independent upper links but is much stiffer when the unified upper link called the Lopes-Link is added.

    I just got back from riding some of my favorte rides at Gooseberry Mesa and Little Creek near Hurricane, and Sedon, and South Mountain in Pahoenix. The 650b Mojo gave me worry free pedal clearance and easier rolling on these very difficult rocky rides and I was riding much better with far greater confidence than the previous times there. And I had only 1 minor tubeless burp doing a sudden stop on a sharp rock while going downhill of the Stan's tubeless rim-strips in Neo-Motos on Blunt rims, when I was using too low front tire pressure on South Mountain. I was using 28/30 psi with compete success.

  57. #57
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    Quote Originally Posted by derby
    The only progress from Ibis on a longer chainstay for 650b that I'm aware of is that they have estimated the tooling cost for the longer dropouts and brake mount. They are busy producing projects already in the pipeline for over a year. I think it will come eventually.
    That sounds great Derby!!! How awesome it would be to have available a 650b Mojo.
    Will it have a higher BB?

    Quote Originally Posted by derby
    Twisting or torsion flex in the swingarm is only a little better than average compared to other bikes with this travel with the original independent upper links but is much stiffer when the unified upper link called the Lopes-Link is added.
    I saw that new link and was thinking it was exactly what the larger riders (or more aggresive riders) of the Mojo was needing

  58. #58
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    Quote Originally Posted by yogiprophet
    How awesome it would be to have available a 650b Mojo.
    Will it have a higher BB?
    It should. It would screw up the handling if they change the BB drop. Going 650b using the current swingarm brings the BB up 1/2 inch to 13.75 inch with Pacenti tires. The raised BB allows nice sag, improves the great handling with far better pedaling clearance for rough, eroded, and off-camber sections of trail, and it's faster because you can pedal sooner out of corners. Now with 650b wheels, I'm glad the Mojo had a very low BB originally.

    Low BB's are only good for shuttle bikes and small sizes, IMO. If you ride rough trails there are better ways to lower the CG.

  59. #59
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    This showed me that the Mojo has extraordinarily minimal lateral flex in the swingarm.
    Good point. I've had no flex rub issues ethier with very little clearance with Moj SL + trimmed Ztr/Neo in rear. This is also with original link.

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    I'm joining the 650b/Mojo club too.
    A bicycle will take you to fantastic places....if you let it.


    Ibis fan since '08 now rolling on the big wheeled Ripley.

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    Seat post rubbing

    Hi, I also have a Mojo that since seeing this thread, I have converted to 650B, I already own a Carver KillerB 650B , so the Mojo was just asking to be done after reading these posts. It worked great and I have been ripping up the trails for about 4 months now. I have been getting a bit of air of some drops lately and have noticed that it was slighty rubbing the seat post, so I had my LBS send the RP23 to the local Push agent hear in Australia and they have refused to put a travel limit spacer, saying that I should not be putting a 650B wheel in it. After much protest they agreed to ask Push in the USA what to do.

    Their question to Push was (Hi, We have a customer that wishes to limit his travel on an ibis mojo, fox rp23 rear shock, to suit the insertion of a 650b wheel. Have you guys had any experience doing such a thing? If so, is it a good idea and what is involved? Some sort of bottom out bumper extension?

    Push USA's answer was and I quote "We haven’t done any shock conversions to address the 650b wheel. We generally don’t support conversions of this nature. I apologize for the inconvenience."

    Mine definitely needs this done, surely they can put a spacer in? Where do I go from here? I definitely don't want to go back to 26" wheels, 650b rocks.
    Last edited by Kimster; 01-08-2010 at 05:16 AM.

  62. #62
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    You should have just asked for the work to be done without mentioning the reason why.

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    that's BS.
    Sorry to say, but that is the way with these things, as everyone just wants to cover there a$$.
    But now you've already told them, and you can't unscramble an egg...
    unless you are Chuck Norris.

    RE: the Mojo, I wonder if there is any compatibility w/ the HD version that will facilitate a 650b hybrid...I am guessing the HD has more clearance than a standard or SL Mojo.
    Ibis seems to be one of those companies that are open minded.

    Either way, good luck.

  64. #64
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    Quote Originally Posted by Kimster
    Hi, I also have a Mojo that since seeing this thread, I have converted to 650B, I already own a Carver KillerB 650B , so the Mojo was just asking to be done after reading these posts. It worked great and I have been ripping up the trails for about 4 months now. I have been getting a bit of air of some drops lately and have noticed that it was slighty rubbing the seat post, so I had my LBS send the RP23 to the local Push agent hear in Australia and they have refused to put a travel limit spacer, saying that I should not be putting a 650B wheel in it. After much protest they agreed to ask Push in the USA what to do.

    Their question to Push was (Hi, We have a customer that wishes to limit his travel on an ibis mojo, fox rp23 rear shock, to suit the insertion of a 650b wheel. Have you guys had any experience doing such a thing? If so, is it a good idea and what is involved? Some sort of bottom out bumper extension?

    Push USA's answer was and I quote "We havenít done any shock conversions to address the 650b wheel. We generally donít support conversions of this nature. I apologize for the inconvenience."

    Mine definitely needs this done, surely they can put a spacer in? Where do I go from here? I definitely don't want to go back to 26" wheels, 650b rocks.
    Great post and good questions Kimster.
    I have asked PUSH to do something like this for me without giving the reason and they said they cannot. I just don't think they want to do anything out of the ordinary and were using the 650b thing as an excuse.
    I forgot what Derby had to say about this and don't have the time at the moment, but I am sure he will come on here and give you something intelligent to think about.
    Cheers

  65. #65
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    here's something cheap and easy you could try:
    DW 5 Spot RP23 mod

    Basically adding a shim to the RP23 can allow you more ramp-up at the end of the shock stroke, thus helping to prevent bottom out.

    If you are you getting rub on when the shock bottoms (or close to bottom out), then this could be a good measure.

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    Limiting shock stroke

    I have been limiting coil shock travel by installing split nylon washer on the shock shaft - I run 2 1/8" washers on my Roco below the bottom out bumper. I have not tried this on an air shock but don't see why it woudn't work. Pull the air can to expose the shock's shaft it has an o-ring only now. I use nylon washers from my local hardware store . Buy them w/ an inner hole the same as the shock's shaft and with a diameter slightly smaller than the air shaft. You need to make a cut in the washer so it can be manipulated onto the shaft. Do not slot the washer or it would slide off . I place the washer flat on a peice of wood, place a razor blade on one side and whack it w/ a hammer (nylon is tough)- makes for a minimal cut. You have to twist the washer over the shock's shaft but now it is pretty much seamless.

  67. #67
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    Quote Originally Posted by sennaster
    here's something cheap and easy you could try:
    DW 5 Spot RP23 mod

    Basically adding a shim to the RP23 can allow you more ramp-up at the end of the shock stroke, thus helping to prevent bottom out.

    If you are you getting rub on when the shock bottoms (or close to bottom out), then this could be a good measure.
    If you look at post #49 and #88 in the link mentioned by sennaster DW 5 Spot RP23 mod, they show bottom bumpers PUSH can add for those bottoming too easily. This should be enough to prevent the seatpost rub landing jumps with 650b in the rear of a Mojo. Full disassemble would be required, so PUSH or their international contractors would have to do it.

    There may be a way to home make a bottom bumper out of a thick rubber o-ring installed by stretching the o-ring over the shock body to stay in the position the PUSH bumper is located. Or possibly by tying and knotting a strip of inner-tube or surgical tubing around the shaft in that location. This would take some experimenting. It could be tested by mounting the shock and sitting and bouncing on the bike with no air in the shock. And like all 26" bike and component conversions to 650b, it is experimental and no manufacturer or certified service company like PUSH would approve it for 650b use, for liability reasons.

    I run a PUSH'd Vanilla RC coil and it's easy to add plastic washer shims under the bottom bumper, which I have done, about 1/16" thick in total, stacking 3 self made shims cut with scissors from thin plastic such as milk carton plastic.

    I need to physically test the just released Mojo HD with my 650b wheel to know for sure if 650b will clear the seatpost better. There should be more chainstay tire clearance for sure. I hope to do that in the next few days or weeks, and report here in a new post.

    BTW, I've ridden the Mojo with Neo-motos a lot in mud now and have not had mud rub issues in the stays unless very sticky build up and catching gravel between the knobs. In 1.5 years of running Neo-Motos in the rear there has been some rub from the cornering knobs gouging the surface about 1/32". That area is over 1/4 inch thick everywhere so I'm not worried, if it cracks someday I'll buy a new swingarm.

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    I am starting to think I should not have mentioned the 650B thing too. The other thing I did not mention, is that although they would not do any travel limiting mods they still pushed the shock and sent it back without first telling me they would not reduce the travel. They should have rung me before doing anything I feel. So I am refusing to pay for it at this stage. I feel I may have some leverage and I will try to get them to put the Push BO Bumper in it that Derby directed me to. Failing that I will add the shim that sennaster mentioned. Thanks guys. I will let you know what happens.

  69. #69
    jrm
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    I tired the ghetto shim

    on a rp23 with the High Volume (larger diameter) canister to increase ramp up on a sultan i converted to 650B. I then went with the (LV) Low Volume canister. Night and day in regard to eliminating the wallow or bottoming of the rp23 with the HV canister. Theyre around $35 USD .

  70. #70
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    Mojo HD 650b fit confirmed

    I got a test ride on the Mojo HD today. And mounted my 650b wheel easily in the new HD swingarm. There's at least 8mm clearance all the way around the knobs of a new 2.3 Neo-moto at the chainstay yoke. And there's pleanty of 6.3 inch bottom travel clearance with the seat tube. The rear end is designed for the Maxel 12mm quick release.

    Overall the bike rode like a dream. I could never in my life grow into the potential of the Mojo HD's capabilities. But I could benefit form the even more forgiving travel and like the standard Mojo but even more so, the natural balance in feel. Plush gradually rising rate compression with a large can RP23. Small bump compliance is close enough to coil that I think this may be the first bike I'll happily ride with air suspension since 2002. The 6.3 inch travel frame with bigger shock is just 6.25 lbs, only 1/2 lb heavier than my standard 5.5 inch travel Mojo with the same type RP23 shock. And its very, very stiff laterally with that damped although minimal flex feel only carbon fiber brings.

    The 67 degree head angle doesn't feel as floppy as other bikes I've demoed with similar head angles. Some of that lack of steering flop is due to the fork on this bike tested was not over sprung for trail riding like most 160mm travel demo bike forks are, and had deeper sag closer to the 35% rear sag as I prefer for trail riding. This bike will feel comfortable and wth air suspension lighter than my coil sprung standard Mojo and do better climbing and epic XC trail bike when there's no big hit and drop off challenges. It can climb, and like the standard 5.5 inch travel Mojo the HD has no benefit using extra damping to pedal hard and efficient, even doing standing sprints has no appreciable squat or bob.

    Next test will be to get a Maxel 12mm rear hub set up for my 650b and test the HD with 650b front and rear. I could only center my wheel using my 10mm bolts in the 12 mm Maxel holes in the swingarm.

    I jumped back on my coil sprung 650b Mojo and suddenly the 5.5 inch travel seems short. I'm spoiled now for a lighter air sprung bike with almost an inch more travel!

  71. #71
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    Sounds like you are going to do your best to spur on the economy derby!

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    Derby,

    I am converting my Mojo SL to 650b. I will be running Stans 355's and my fork is the RLC 140mm. So I'm down to tire choice. Would you happen to know if there is enough clearance with this fork for a Nevagal 2.35? My old set up on the 26" wheels was Nevagal in the front and SB8 rear. I'm really having trouble finding a 650b tire comparable to SB8. Someone suggested Racing Ralph. Any experience with this? Trail is mostly hard pack.

  73. #73
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    I'll chime in. I'm on the 650b Racing Ralph and I like it. It doesn't have very big knobs but rolls real good. I've got a fork like you have but never tried putting my wheel in as I went to 20mm TA.
    A bicycle will take you to fantastic places....if you let it.


    Ibis fan since '08 now rolling on the big wheeled Ripley.

  74. #74
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    Quote Originally Posted by txnrider
    Derby,

    I am converting my Mojo SL to 650b. I will be running Stans 355's and my fork is the RLC 140mm. So I'm down to tire choice. Would you happen to know if there is enough clearance with this fork for a Nevagal 2.35? My old set up on the 26" wheels was Nevagal in the front and SB8 rear. I'm really having trouble finding a 650b tire comparable to SB8. Someone suggested Racing Ralph. Any experience with this? Trail is mostly hard pack.
    I bought some 650b Nevegal 2.35 on sale, but have not mounted them yet. I should do that as a rainy day stoke. And give them a test at least on the front on wet trail, as this is why I got them having the duel compound and softer rubber on the side knobs than the Neo-moto. I think someone else confirmed the 650b Nevegal 2.35 clear a Fox arch about the same as a Neo-Moto 2.3, and unless you have a modified Fox 32 fork they never bottom within 3/4 inch to potentially slightly rub the crown with 650b 2.3 sizes.

    For a back wheel I really like the Neo-moto more than the Nevegals I've ridden as 26 inch. The Neo-moto's roll as a back wheel easier. And Neo-moto side grip is better, although maybe that's more due to the advantage of 650b cornering grip in general. I must test my Nevegal 650b! And will do so very soon.

    I think others have recommended the 650b Racing Ralf as a great rolling tire. I tried larger volume SB8's in 26" a few years ago before going to 650b and did not like them for my interests, I hate skidding so easily, if I still had them I think I'd clip off many intermediate side knobs to gain side knob grip. Personally I liked the Mutanoraptor tires looser conditions handling grip and breakaway feel better and they roll hardpack at least as easily as SB8, but that's off topic except the Racing Ralf have a somewhat similar design in some ways with the Mutano and look better in my opinion over a wider variety of surface than the SB8 tread.

    The Quasi-moto is also very easy rolling and corner grip and braking is very good until they wear off the knob's sharper edges. Problem is they don't have much knob and wear beyond good grip in a short time. The Racing Ralf design should hold up longer with relatively good handling grip.

  75. #75
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    Thank you both for your answers. I guess I didn't really factor in the TA as being an issue with clearance. Mine is the 15mm TA. I may just try a Nevagal 2.3 in the front and Nevagal 2.1 rear as a starting point and experiment from there.

  76. #76
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    Quote Originally Posted by txnrider
    Thank you both for your answers. I guess I didn't really factor in the TA as being an issue with clearance. Mine is the 15mm TA. I may just try a Nevagal 2.3 in the front and Nevagal 2.1 rear as a starting point and experiment from there.
    Post up when you complete this Duane. I'm thinking of going to 650 as well.

  77. #77
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    Woody,

    Wheels are done. I just need to pick them up. You can check them out if you want. They are still up at Hammerhead. Take your bike up there and see if they will fit yours . I ended up going with the 2.3 in the front and 2.1 back.

    Duane

  78. #78
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    Quote Originally Posted by derby
    For a back wheel I really like the Neo-moto more than the Nevegals I've ridden as 26 inch. The Neo-moto's roll as a back wheel easier. And Neo-moto side grip is better, although maybe that's more due to the advantage of 650b cornering grip in general. I must test my Nevegal 650b! And will do so very soon.
    FWIW, the 2.1 Nevegal 650b as a back wheel on the Mojo is a no go. It's rubbing. I'll be cutting the tire tonight .

  79. #79
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    Bummer Duane, but those tires are pretty meaty, maybe a less knobby one would work better. On a Marin note, it looks like the shock never completely bottomed out like I though it would, so a 650 might fit after all. By the way, check your mojo pm.....

  80. #80
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    Quote Originally Posted by 4212darren
    I'll chime in. I'm on the 650b Racing Ralph and I like it. It doesn't have very big knobs but rolls real good. I've got a fork like you have but never tried putting my wheel in as I went to 20mm TA.
    Have you found the Racing Ralph to work without the need to shim the shock?

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    Never shimmed the shock, maybe I should.
    A bicycle will take you to fantastic places....if you let it.


    Ibis fan since '08 now rolling on the big wheeled Ripley.

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    I noted the discussion about swapouts with interest. I've been thinking with many frame makers going to swapouts there is a potential for 650b swapouts that optimize many 26" frames for 650B. I hope we see swapouts for 650b conversion as standard fare in a few years.

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    Hey DERBY..I'm very interest in this 650mojoHD Is this ideal for aggressive all mountain type of riding? Damn...m all excited with this new project!! Can I use my existing Lyrik 160 fork??? U also mentioned that ibis prohibits this type of convertion coz m worried about warranty issues!?!? What is the burliest avail. 650b wheel build? Thanks!!

  84. #84
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    I am seriously looking at getting a Mojo HD to replace my Cdale Moto and deffineltly going 650b on it. Hope I can retro fit my King hubs to fit the Maxle.

  85. #85
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    Quote Originally Posted by jaidylim
    Hey DERBY..I'm very interest in this 650mojoHD Is this ideal for aggressive all mountain type of riding? Damn...m all excited with this new project!! Can I use my existing Lyrik 160 fork??? U also mentioned that ibis prohibits this type of convertion coz m worried about warranty issues!?!? What is the burliest avail. 650b wheel build? Thanks!!
    I'm also looking forward to getting an HD to convert into 650b.

    I'll be swapping my Lyrik coil u-turn on my Mojo C over to the HD. And using a coil shock (TBD).

    I did fit my rear wheel with 2.3 Neo-motos into the rear of a prototype HD a year ago, there is more clearance than with the Mojo SL. Should be no problem with clearance, possibly the larger Kenda Nevegal 2.35 will clear also (which does not clear the SL).

    The toughest current 650b wheel build is using Velocity P35 rims and Pacenti Neo-motos or Kenda Nevegals, using your favorite hub, and 2.0 straight gauge spokes, or 20./1.8 DB spokes, 3x for durability.

    I don't think the relatively light weight single-sidewall 650b tires available now are up to the potential of the big air FR or DH race capabilities of the HD. I'm planning on building some 35mm wide rim 26" wheels with big heavy DH tires for using at ski resort bike parks. 650b for trail/AM riding.

    Ibis does not have a written warranty for 650b use, but they don't have any written or stated policy preventing 650b.

  86. #86
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    Quote Originally Posted by derby
    I'm also looking forward to getting an HD to convert into 650b.

    I'll be swapping my Lyrik coil u-turn on my Mojo C over to the HD.


    Ibis does not have a written warranty for 650b use, but they don't have any written or stated policy preventing 650b.

    I deffinetly like the Lyrik U-turn coil fork on my Moto.

    Don't ask don't tell.


  87. #87
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    Hi
    I have been riding 650b front wheel for one year and i find it perfect on the mojo. Much better than a 29 full.
    I woul buy the rear swingarm immediatly if possible.

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    I am planning an ultralight 650b build around the Mojo HD, with travel reduced to 140 (in order to offset the taller wheels) and keep the bb height within reason. Will use a Fox Float130 front fork for same reason. should be stiff and agile. By contrast, I have tried the 650b in the fornt only ) on my Mojo SL and found that the increase traction and tracking of the 650b wheel completely overwhelmed the Mojo Sl and amplified it's inherenet rear swingarm flex. The Mojo HD chassis will overcone the ghost riding rear end, is my hope.

  89. #89
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    Quote Originally Posted by buggymancan
    I am planning an ultralight 650b build around the Mojo HD, with travel reduced to 140 (in order to offset the taller wheels) and keep the bb height within reason. Will use a Fox Float130 front fork for same reason. should be stiff and agile. By contrast, I have tried the 650b in the fornt only ) on my Mojo SL and found that the increase traction and tracking of the 650b wheel completely overwhelmed the Mojo Sl and amplified it's inherenet rear swingarm flex. The Mojo HD chassis will overcone the ghost riding rear end, is my hope.
    I'm totally with you on the HD140/650b plan, but regarding SL flex.... I'm running 650b/26 on mine, and my new SL with the latest links is NOTICEABLY stiffer than my previous '07 std mojo. You might try a link update if you're not there yet on ordering up an HD.

  90. #90
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    Since I already have a Mojo SL running 650b's, a long-legged 650b HD could be a barrel of monkeys even if it doesn't turn out to be practical. It's partly built now, so hopefully it will be ready to roll no later than Memorial Day.

    Just for fun - Pic of my 650b SL with a couple of Scar's lights on Wednesday night.

    650b Mojo-090-1.jpg

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    Did you have to shim your shock in order to prevent seat tube rub on your Sl?

  92. #92
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    Quote Originally Posted by buggymancan
    Did you have to shim your shock in order to prevent seat tube rub on your Sl?
    I have been running my Mojo SL 650B front and rear for over a year now, 2.3 Neo front, 2.1 rear. I had rubbing issues with 2.3 in rear. Fox Talas RLC 150/130/110, almost always run at 150. Pushed RP23 that I shimmed myself. 650b shock bottom-out shim for seat tube clearance
    I have installed the newest lower link and it does make a significant difference. Simply put this bike and setup is just awesome! I can't ride it enough.

  93. #93
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    wrong thread (dump forum software)

    moved to main thread.

  94. #94
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    Mojo SL-R does NOT clear 650b .

    Just a head's up.. The new model Mojo SL-R, is a very nice improvement in lateral and torsional stiffness while being slightly lighter than the SL.

    However, the bigger chainstay yoke area, while adding to stiffness, takes up too much room now to clear a 650b wheel. Possibly the smallest 650b XC race tire might barely clear, but this exceptionally durable bike deserves more durable tires. A Quazi-Moto would not clear, maybe there are smaller XC racer tires.

    The earlier model SL is unchanged and easily clears 650b.

  95. #95
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    Quote Originally Posted by derby
    Just a head's up.. The new model Mojo SL-R, is a very nice improvement in lateral and torsional stiffness while being slightly lighter than the SL.

    However, the bigger chainstay yoke area, while adding to stiffness, takes up too much room now to clear a 650b wheel. Possibly the smallest 650b XC race tire might barely clear, but this exceptionally durable bike deserves more durable tires. A Quazi-Moto would not clear, maybe there are smaller XC racer tires.

    The earlier model SL is unchanged and easily clears 650b.
    Doh! Good to know. Much as the SL-R's improvements seem pretty nice, the 650b option on the SL outweighs them all in my book.

  96. #96
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    Quote Originally Posted by kestrel242
    Doh! Good to know. Much as the SL-R's improvements seem pretty nice, the 650b option on the SL outweighs them all in my book.
    The SL-R center frame geometry is the same as the C and SL, which can be bolted up to the older swingarms. About 85 to 90% of the stiffness improvement was done by the center frame changes (tapered head tube, bigger down tube, wider press fit BB housing, integrated front der hanger bringing more seat tube stiffness).

    The SL-R's 12mm Maxel is the big difference to the swingarm. A 10mm bolt-on through axle in the rear is just as stiffening compared to QR skewers. The SL-R's thicker yoke area of the chain stay is a minor improvement compared to the much bigger axle in the swingarm.

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    Fox Talas 140

    I have a Fox Talas 140. Do you think I'd have enough clearance to go with a 650b wheel or would I need the additional axel to crown length with a 150 fork?

  98. #98
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    Quote Originally Posted by bicyclemark
    I have a Fox Talas 140. Do you think I'd have enough clearance to go with a 650b wheel or would I need the additional axel to crown length with a 150 fork?
    Yes, your fork will clear. Longer travel and A-C don't make a difference in the amount of tire clearance at the arch. I ran a qr 140 Float (same lowers as your Talas) w 650b and it had the best clearance of the 3 forks I've tried.... Go for it!

  99. #99
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    Quote Originally Posted by lml427
    I have been running my Mojo SL 650B front and rear for over a year now, 2.3 Neo front, 2.1 rear. I had rubbing issues with 2.3 in rear. Fox Talas RLC 150/130/110, almost always run at 150. Pushed RP23 that I shimmed myself. 650b shock bottom-out shim for seat tube clearance
    I have installed the newest lower link and it does make a significant difference. Simply put this bike and setup is just awesome! I can't ride it enough.

    lml,
    So the 2.1 Neo Moto 650B works for the Mojo SL rear without any modifications then? What rim are you using? I want to match my rear rim with my front rim (Velocity Blunt), but I've been reading that the width of the Velocity rim (28mm) would increase the tire width once it's set. Would the 2.1 Neo Moto on the Blunt rim be an issue?

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    Red Bank Rider,
    I have the 28mm Blunts front and rear. The 2.1 does not rub on my rear triangle. Somewhere on this forum it was said that rear triangles can very in clearance slightly, so be aware of that. The only modification I did was to limit the shock travel with a shim as described in the link. The shimming shortens the travel so the tire will not rub the seat tube. You should always check your full suspension travel with the air out of the shock.
    Edit: I do have the newest lower link and Hadley hubs with 10mm thru bolt rear. The bike rides stiff under my 6' 4", 225lb.

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