The 97.5 AM Bike Thread (29" front, 27.5" rear wheels)- Mtbr.com
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  1. #1
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    Idea! The 97.5 AM Bike Thread (29" front, 27.5" rear wheels)

    Also known as "reverse mullet" (and a few other colorful names) a 97.5 is a bike build with mixed wheel sizes, more specifically, a 29" wheel at the front and 27.5 at the back.

    The first one I remember seeing on sale was the Foes Mixer, which had good reviews and was revolutionary for its time. Now that the UCI has greenlit mixed wheel sizes back in competition, expect to see more reverse mullet bikes on the media.

    This thread is to discuss possible builds, actual retail releases, and share experiences with building, riding, and racing 97.5 AM bikes.

  2. #2
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    I ride a 27.5 front and a 26 rear. With Maxxis 2.5s there is hardly a difference in diameter. I cant quite fit a 27.5 wheel in the back, otherwise Id try it. No downsides, so far.

  3. #3
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    Pennygnarthing.

    I rode a Tantrum mixer... The geo wasn't quite what I was looking for but I think there's huge potential in the combo. Why not take the best of both wheel sizes?

  4. #4
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    I always loved riding my B6er. I would definitely be down to try one, if you could keep the SA at 75.

  5. #5
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    Martin Maes is racing the EWS with a mixed wheel setup. Photo and quote from Pinkbike:





    Martin has been testing the 29'' wheels on his new Force frame over the winter and at the moment he's running a 29'' front wheel and a 27.5'' rear wheel combo. The cockpit sports a 50mm stem with 780mm bars.



    I'm guessing he's using a 50mm stem to match the 51mm offset on the fork. I hope he does well in Rotorua.

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  6. #6
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    Liteville has been doing this for years. Their larger bikes use 29F and 27.5R. Smaller sizes use 27.5F and 26R.

  7. #7
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    I've been on a Tantrum 29ee(140mm)/27.5(160mm) and it's an amazing bike coming off a Lenz 29er(100mm f&r). No regrets with a mixed up bike for me.

  8. #8
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    Finn Illes narrowly missed the top step (by 0.09 sec) at Crankworkz today. I know it's DH but it shows running a 97.5 setup can be a boost for some riders and riding styles.

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  9. #9
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    Martin Maes just won EVERY stage of the Rotorua EWS on his 97.5 Force.



  10. #10
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    IAUI switching a 27.5 wheel and fork to a corresponding 29" setup would raise the bike's front end by about 35-40mm which is quite a lot and probably throws the bike geometry pretty seriously out of whack. I wonder how much front travel Maes has in his rig?

  11. #11
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    Martin's probably using a 150mm 29 fork. The Force was designed with a 160mm 27.5 fork in mind, which has an axle to crown length of about 549mm (Fox 36). A 150mm 29 fork has an A2C of 557mm. Even at 160mm, we're only looking at an 18mm difference.

    The Sensor and Force have the same front triangle, too, so the geo won't necessarily get that screwed up by using a 29 front wheel. Offset bearings and anglesets are also available to mitigate changes with their setup.

  12. #12
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    Last Saturday a friend acquired a used Production Privee Shan 27.5" frame. The plan was to build it spending zero extra cash, using just spare/borrowed parts. He only managed to find a 29" 120mm fox 34 with a 29" wheel and 2.6 tyre for the front, which proved to be roughly equivalent in length to a 27.5 140-150mm fork (frame is rated for 140-160mm). The rear is a 27.5 Flow with a 2.25 tyre and the rest of the build came from components we had laying around.

    We proceeded to test it immediately on some nearby urban trails, and surprise surprise, it rode just fine. Nothing weird about the handling, climbing, descending or turning. Just some extra stability on the front end compared to my own 27.5 AM hardtail with similar geo. . Using our phones the head angle measured around 65.5 and the seat tube around 72 degrees. BB height came out around 315mm.

    None of us has tried the bike in full 27.5 configuration so we can't compare, but as a 97er it felt perfectly natural.

    The 97.5 AM Bike Thread (29" front, 27.5" rear wheels)-ppshan-97er.jpg

  13. #13
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    Bike: Kona Process 153 97.5
    Rider: 5'6" (168 cm), 29 inch inseam

    Getting the rear shock to track the same way as the fork took a bit of tuning and testing. After doing 5 runs, I was surprised to see that I beat a Strava PR in 1 segment by 9 seconds (1:53 to 1:44) on my 5th run. I wasn't even pushing as I focused on getting the suspension dialed.

    I'm definitely sticking with this build for the time being. There's a bit of understeer but all you have to do is lean the bike more. Otherwise, it's very maneuverable. It flies higher on jumps and that's probably due to the added speed you carry (and the really short chainstays of the Process).

    The hype is real.

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  14. #14
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    I'm a big fan of this concept. I purchased a Pivot 5.7c about four years ago, and while it is a 26" frame, Pivot had blessed it to run with 27.5 f/r. Tried that but didn't like the limited tire size in the back, the reduced rear travel and the higher BB. Put a big 26" tire in the back and it just worked. Read all the info on Liteville and Foes and the science is interesting. I've moved on to another bike, but the Pivot made its way to my son so I still get to ride it every now and then. Doesn't give up much to today's geo bikes really.

    The 97.5 AM Bike Thread (29" front, 27.5" rear wheels)-img_2648.jpg

  15. #15
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    Quote Originally Posted by LoneStar View Post
    I'm a big fan of this concept. I purchased a Pivot 5.7c about four years ago, and while it is a 26" frame, Pivot had blessed it to run with 27.5 f/r. Tried that but didn't like the limited tire size in the back, the reduced rear travel and the higher BB. Put a big 26" tire in the back and it just worked. Read all the info on Liteville and Foes and the science is interesting. I've moved on to another bike, but the Pivot made its way to my son so I still get to ride it every now and then. Doesn't give up much to today's geo bikes really.

    Click image for larger version. 

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    Good looking bike! Did you measure the change in BB height with the 1" smaller rear wheel? I'm assuming .5"?

  16. #16
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    Quote Originally Posted by slimat99 View Post
    Good looking bike! Did you measure the change in BB height with the 1" smaller rear wheel? I'm assuming .5"?
    I think it was closer to 0.4" if I recall. This also was using a 140mm fork rather than the 150 spec'd on the 5.7c. The BB height would be less if I had a less voluminous tire on the front. Those e*13 tires run pretty big on on 30mm rim. It was still high by today's standard, but pedal smacks didn't happen as often

  17. #17
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    Quote Originally Posted by Verbl Kint View Post
    Bike: Kona Process 153 97.5
    Rider: 5'6" (168 cm), 29 inch inseam

    Getting the rear shock to track the same way as the fork took a bit of tuning and testing. After doing 5 runs, I was surprised to see that I beat a Strava PR in 1 segment by 9 seconds (1:53 to 1:44) on my 5th run. I wasn't even pushing as I focused on getting the suspension dialed.

    I'm definitely sticking with this build for the time being. There's a bit of understeer but all you have to do is lean the bike more. Otherwise, it's very maneuverable. It flies higher on jumps and that's probably due to the added speed you carry (and the really short chainstays of the Process).

    The hype is real.

    Sent from my SM-G955F using Tapatalk
    Is that originally a 27.5" or a 29" Process? Looks really nice, almost like it was meant to be like that in the first place.

    I am strangely attracted to the 97.5" concept even though it probably doesn't make sense in the terrain I ride.

  18. #18
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    Since the 29 and 27.5 Process had the same rear triangle, I thought it would be better to use a 29 frame for the build.

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  19. #19
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    you'd probably want the highest offset fork you can get right? to keep the steering reasonably quick.

  20. #20
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    Yes, I'm sticking with a 51mm rake for the moment.

    * * *

    The first races of both the EWS and World Cup DH were both won on a 97.5 bike. With the latter getting a 1-2 for the mixed wheelsize, too.

    Choices are good.



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  21. #21
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    I think Danny Hart would have the same result regardless of wheel size. First (Bruni) and third (Brosnan) were on 27.5.

    IMO...wheel size makes very little difference in pro DH and Enduro race results. The rider that races the cleanest run wins...regardless of what wheel size they are on.

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    Quote Originally Posted by RS VR6 View Post
    I think Danny Hart would have the same result regardless of wheel size. First (Bruni) and third (Brosnan) were on 27.5.

    IMO...wheel size makes very little difference in pro DH and Enduro race results. The rider that races the cleanest run wins...regardless of what wheel size they are on.
    Bruni was on a mixer too.

  23. #23
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    Marco Osborne runs a mullet setup, bike and haircut! Just won the TDS on a Patrol.

  24. #24
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    I'm curious about converting my Scout 275 (27.5+) to a 29er front. Not sure it'll be as simple as just changing the front wheel & tyre though. Emailed Nukeproof to see what they suggest. Waiting to hear back

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    I should add, that I'm a shorter rider, about 5'6" and whilst I really like how my 29er rolls and climbs, I find myself a lot more maneuverable on my 275 when I hit switchbacks and tighter features downhill. I'm hoping for a best of both worlds with this.

  26. #26
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    Get out of the gutter and onto the mountain top.

  27. #27
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    They should've tested it on a 2+min track.



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    Quote Originally Posted by Verbl Kint View Post
    Martin's probably using a 150mm 29 fork. The Force was designed with a 160mm 27.5 fork in mind, which has an axle to crown length of about 549mm (Fox 36). A 150mm 29 fork has an A2C of 557mm. Even at 160mm, we're only looking at an 18mm difference.

    The Sensor and Force have the same front triangle, too, so the geo won't necessarily get that screwed up by using a 29 front wheel. Offset bearings and anglesets are also available to mitigate changes with their setup.
    The A-C isn't the only place where stack would grow though. You've also got the increased height from the ground to the axle due to the larger wheel. So that adds ~18mm to the stack in addition to whatever the A-C difference is when moving to a 29er fork.

  29. #29
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    I rode a lot of motocross in the 90s so Im attracted to the ride qualities of a mixed wheel size bike.

    I experimented with a 27.5 rear wheel on my 29er Trek Rumblefish a few years ago and enjoyed the cornering but had a lot of pedal strikes.

    One of my current bikes is a Tantrum with a 160mm 29er fork and the frame has modular rear drop outs designed for 27.5. Its amazing

  30. #30
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    My Liteville was like this years ago, I sold it and moved on.
    I like to fart when I'm in front of you on a climb:skep:

  31. #31
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    Done this concept three times.

    Mixed wheeled my Switchback Unveil 9. Mixed results. Was ok I guess. But I wasnt* that fast back then.

    Tried it on a 2016 Stumpjumper. This is amazing, reduced the rear travel to 140 and put a 140 29er fork on the 27.5 frame. Very fast, but only rode this 2x with this setup. Building it back out in this config when money allows.

    Current mullet bike is a Foes Analog. 140 29er fork, with WAO Agents, and WTB Vigilante 2.6s. This is my favorite bike so far. BB is a reasonable 12.5". Its way more stable hitting things hard, and when you corner, it has a way of carving harder than with the same wheels. Combined with the big WTB tires, it's a monster. Will take a photo tonight.

    Have a SWORKS Enduro on the way that going to get the same treatment.
    Last edited by FastBanana; 05-29-2019 at 10:19 AM. Reason: Typo

  32. #32
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    Been thinking to do the same on my bike. What would be better, reverse mullet a 29er frame or a 27.5?i have a 2016 yt capra.

  33. #33
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    From what I've read, 27.5 frame is what most are doing.

  34. #34
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    Quote Originally Posted by Loic Donny View Post
    Been thinking to do the same on my bike. What would be better, reverse mullet a 29er frame or a 27.5?i have a 2016 yt capra.
    You need to do some geo-checking.

    Try out https://bikegeo.muha.cc/ and plug in the numbers of what your likely theoretical setup will look like.

    I chose a 29" Kona Process 153 but used a 27.5 rear wheel. The reason is that, for the Process 153, the 29" and 27.5" models share the same rear triangle.



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  35. #35
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    I'd be all over this if my geo would not be wrecked on my current bike. Particularly STA but to a lesser extent BB height. Downhill sharp turns are my arch enemy and I feel a Mullet bike would assist with that.

    Good luck with ya'lls set ups!

  36. #36
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    Quote Originally Posted by Suns_PSD View Post
    I'd be all over this if my geo would not be wrecked on my current bike. Particularly STA but to a lesser extent BB height.
    I got into this because the geo works for my bike... okay and because I had an extra 29+ plus front wheel/tire laying around with nowhere else to run it.

    2017 Norco Torrent HT (designed for 27.5+)
    Had swapped forks with another bike so lost 20mm A/C (10mm travel)
    Front wheel is a WTB Scraper with a 29x3.0 Bomboloni
    Found a 27.5x3.0 Ground Control for cheap, to bring the rear end up a little.

    Front wheel/tire > rear by about 35mm.... so now I'm maybe 15mm taller in front than stock.

    I know this slackens HTA to about 66* (maybe less), and STA to less than 72*... I thought that the bike might climb poorly but two test rides in have disappeared those worries! I just took it out for a long, techy climb that I've done like 20 times and set a PR right out of the gates . I think I might have set a PR on any of my bikes that day, but still it reassures me this setup is fine for me going up.

    And going down is a no-brainer, of course. Love that big front tire, glad to get it back into action .
    Attached Thumbnails Attached Thumbnails The 97.5 AM Bike Thread (29" front, 27.5" rear wheels)-img_20190630_110448.jpg  

    Last edited by S​​usspect; 07-04-2019 at 01:15 PM. Reason: pictures no workie

  37. #37
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    Has anyone seen this done with an Ibis Mojo3?

    I've been looking at replacing the whole bike with a 29er, but might try out this idea first.

    It's a 2016 Mojo3 with a Large frame. Can someone help me figure out which 29er fork would be best and what the final geo numbers might look like?

    I also have a new 27.5+ Fox Factory 34 fork sitting in a box that allegedly fits up to 29x3, and I even have 120, 130, and 140mm cartridges for it. (525.5, 535.5, and 545.5 a2c measurements respectively). Do you think I could use this instead of a 29-specific fork?

    Thanks ahead of time for the help.

  38. #38
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    Quote Originally Posted by paleh0rse View Post
    Has anyone seen this done with an Ibis Mojo3?

    I've been looking at replacing the whole bike with a 29er, but might try out this idea first.

    It's a 2016 Mojo3 with a Large frame. Can someone help me figure out which 29er fork would be best and what the final geo numbers might look like?

    I also have a new 27.5+ Fox Factory 34 fork sitting in a box that allegedly fits up to 29x3, and I even have 120, 130, and 140mm cartridges for it. (525.5, 535.5, and 545.5 a2c measurements respectively). Do you think I could use this instead of a 29-specific fork?

    Thanks ahead of time for the help.
    It sure sounds like you could unbox that Fox 34 and run it, and it's a bonus to be able to change up the travel. You don't mention what the A/C is on your current fork, but reducing A/C with the new Fox fork will offset the 29er wheel height in the front, and minimize any changes to geometry you would otherwise get from different wheel heights front/back.

    There's another thread about this where a forum member has done some work with bikeCAD, and that's a good way to visualize what's going on with all the angles.

    Check it out here:

    https://forums.mtbr.com/general-disc...n-1106491.html

  39. #39
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    That was my thread, yeah the bikecad that a fellow forum member got me into really helps visualise the changes. Understanding how those changes will actually feel is a different story though.

  40. #40
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    Quote Originally Posted by S​​usspect View Post
    It sure sounds like you could unbox that Fox 34 and run it, and it's a bonus to be able to change up the travel. You don't mention what the A/C is on your current fork, but reducing A/C with the new Fox fork will offset the 29er wheel height in the front, and minimize any changes to geometry you would otherwise get from different wheel heights front/back.

    There's another thread about this where a forum member has done some work with bikeCAD, and that's a good way to visualize what's going on with all the angles.

    Check it out here:

    https://forums.mtbr.com/general-disc...n-1106491.html
    Great info and link, thank you!

    BikeCAD sounds like a good plan. I just need to dig up all the numbers.

  41. #41
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    Quote Originally Posted by S​​usspect View Post
    You don't mention what the A/C is on your current fork, but reducing A/C with the new Fox fork will offset the 29er wheel height in the front, and minimize any changes to geometry you would otherwise get from different wheel heights front/back.
    My current fork info:
    2016 RockShox Pike Solo Air RCT3 140mm, 27.5 boost, 42mm offset, 532mm A2C

    The specs for the Fox F34 fork I have in mind to run 29x2.6 tires:
    120mm = 51mm offset, 525.5mm a2c
    130mm = 51mm offset, 535.5mm a2c
    140mm = 51mm offset, 545.5mm a2c

    Stock Geometry:
    SIZE: LARGE
    C-to-T Size: 470mm
    EFF Top Tube: 617mm
    Head Tube Length (4mm stack of lower cup not included): 117mm
    Chain Stay: 425mm
    Seat Tube Angle: 73.7
    Head Tube Angle: 67.1
    Wheelbase: 1158mm
    BB Height (with Maxxis Minion DHF 27.5 x 2.6" tires): 337mm
    Stack: 602mm
    Reach: 441mm
    Standover: 724mm

    If I run the new fork at 130mm, the a2c only increases by 3mm. My biggest concern is probably the STA. Does anyone see anything else that could get thrown completely out of whack with the above numbers?

  42. #42
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    When you account for the larger wheel diameter (basically add about 19mm to a2c) in addition to the a2c length I think even the 120mm fork will slacken the bike somewhat. I'd be especially wary of that if you do a lot of techy climbing.

  43. #43
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    Mine slackened out about 1.5 according to bike cad. Tbh the biggest disadvantage I've found so far is that you don't really want to run a skinnier rear tyre, that will increase the geometry changes beyond what is already at the limit in my mind. You can adjust bar/stem height and riding position to balance the decrease sta to a point.

  44. #44
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    Quote Originally Posted by paleh0rse View Post
    [B]If I run the new fork at 130mm, the a2c only increases by 3mm. My biggest concern is probably the STA. Does anyone see anything else that could get thrown completely out of whack with the above numbers?
    Like these other guys have said, running this fork at any travel setting is going to slacken the bike to some degree, due to the 29er wheel/tire raising the front end more than you are able to eliminate with A/C change.

    I can't remember what the general rule of thumb is, but if 1/2" slackens your HTA by one degree (just for example, don't know if that's accurate) you might end up 1.5* slacker like crembz did. I'd say try it and see. You can reduce to 120, and/or run a taller rear tire to bring things closer to original if you find 130 too slack.

    STA can be mitigated to some extent by sliding your seat forward on the rails.

    At this point, you're kind of committed to this experiment, since you've told us all about it 😜.

  45. #45
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    Could someone please educate me on the advantages of running a 97.5. Im most likely getting a GG Smash and you can swap out the rear for a 155 27.5 instead of the 145 29 wheel or even 170/165(I feel this is too much bike for my normal riding ). Ive seen a couple of YouTube comparisons and race results tend to be mixed, I think the riders wouldve placed where they did on any wheel size. It just seems like a cool to try thing than any real, I wouldnt say advantage but maybe cornering, righty switchbacks, jumping, rock gardens/roots improvements. For the GG Smash, obviously adding more rear travel could be helpful but other than that Im not sure if its worth it. Thoughts?

  46. #46
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    This is pretty cool that GG is offering this option. Curious if the geometry remains the same between rear wheel size/travel... if geometry does stay the same, you *might* find the 27.5 rear feels a little more maneuverable/quicker in the rear end and it might change/improve cornering.

    Many of us on here are running the 97.5 because we started with a 27.5 bike and wanted the added rollover of a 29 up front. We've had to do some gymnastics to keep geometry within reason, because of changing the height of the front tire. Presumably GG and other bikes sold as mullets (like the Foes Mixer) have all those problems sorted.

    I would read a few reviews from GG owners, if you can. Honestly I wouldn't have thought of going mullet if I had a 29 rear wheel to run a 2.8 on.... I'd just be running my hardtail as a 29+. But as it is, I've been running a 27.5x3.0 on the rear, and while it'd be inaccurate for me to call the back of my bike "quick" with all that heavy rubber.... with all things considered, the 'plus mullet express' has been working just fine.
    Last edited by S​​usspect; 07-13-2019 at 09:40 AM. Reason: spell check

  47. #47
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    I'm curious whether anyone has done this to a 29er. As susspect said most have put a 29er front on a 27.5 frame. I'm thinking along the same lines, would it make a 29er more maneuverable.

  48. #48
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    Quote Originally Posted by crembz View Post
    I'm curious whether anyone has done this to a 29er. As susspect said most have put a 29er front on a 27.5 frame. I'm thinking along the same lines, would it make a 29er more maneuverable.
    Seen it done both ways, and have done it both ways.

    I have a hardtail with a high BB, 29er. 67 degree head angle stock with a 140mm fork.

    So I mixed it, with everything from a 140 to a 170 fork. 170 it ends up with a 63' head angle. Honestly, it *should* ride like shit like that. Its nasty, climbs a bit vague, but its manageable. I like how the 27.5 rear dropped the BB to 12" or so, as I like it low. (Hardtail of course, my preference for FS is 13.25 ish)



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  49. #49
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    I actually built my girlfriend's bike up with a 27.5/26 setup. Ride's pretty well especially if you're doing a fixed xc height seatpost as because you cant be centered with your mass, the additional grip and roll over in the front makes okay to stick the saddle in your chest and you mass over the rear wheel and still make some corners...

    Check it out!

  50. #50
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    Did this setup with my GT Zaskar about 3 years ago, just to try it out. Ran a 2.5 Bronson out back with good results. The BB ending up being too low for NE terrain, so switched it back to 9r out back with a 2.35 Ikon and the results were better. Better BB clearance, better traction, better rolling and just better all around. The mixer application might be better for AM or DH than the XC bike I have.
    Attached Thumbnails Attached Thumbnails The 97.5 AM Bike Thread (29" front, 27.5" rear wheels)-img_0975.jpg  

    The 97.5 AM Bike Thread (29" front, 27.5" rear wheels)-img_0622.jpg  

    The 97.5 AM Bike Thread (29" front, 27.5" rear wheels)-img_0303.jpg  

    17 Fuel EX 9.9 (in progress)
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    As of today at least one other manufacturer that I know of other than Foes now has a production 97.5 bike (see link below), I wonder if the new wave of interest in mixed wheel bikes will be just a fad like it has been in the past or if they might be here to stay now. Until big brands that capture the spotlight like Specialized, Santa Cruz, Ibis, Trek etc. make production 97.5 bikes though I am leaning towards a fad. The concept though has always sounded interesting to me and like its some of the best of 29 and 27.5 all in one so I wouldn 't mind if mixedf wheel bikes become a thing.

    Here is the production bike in question, a new alchemy: https://www.pinkbike.com/news/alchem...llet-bike.html

    It would be cool to try a 27.5 wheel on the back of the new Hightower V2, the bike has a high geo mode so it might work. The bike is designed for 27.5+ tires in that case though but 2.6 tires front and rear might be interesting if you don't mind pedal strikes. For now I am sold on 29er but I'll consider it as a possibility if I buy new wheels.

  52. #52
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    I think mullet bikes are the future for many applications and sized riders (I don't believe any specific wheel size is ideal for every single sized rider out there), but the mullet conversions just come with way too many compromises imo.
    Personally I won't own one for years because I adore my current bicycle, but if I was shopping for a new bike now, it would likely be a requirement and therefore would likely be a GG cause it seems like one of the few high end, proper geo mullet choices.

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  53. #53
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    Quote Originally Posted by agreenbike View Post
    As of today at least one other manufacturer that I know of other than Foes now has a production 97.5 bike (see link below), I wonder if the new wave of interest in mixed wheel bikes will be just a fad like it has been in the past or if they might be here to stay now. Until big brands that capture the spotlight like Specialized, Santa Cruz, Ibis, Trek etc. make production 97.5 bikes though I am leaning towards a fad. The concept though has always sounded interesting to me and like its some of the best of 29 and 27.5 all in one so I wouldn 't mind if mixedf wheel bikes become a thing.

    Here is the production bike in question, a new alchemy: https://www.pinkbike.com/news/alchem...llet-bike.html

    It would be cool to try a 27.5 wheel on the back of the new Hightower V2, the bike has a high geo mode so it might work. The bike is designed for 27.5+ tires in that case though but 2.6 tires front and rear might be interesting if you don't mind pedal strikes. For now I am sold on 29er but I'll consider it as a possibility if I buy new wheels.
    Personally, I wonder how the Alchemy rides. It looks like they just changed the linkage of the 29er to keep the geometry the same. Personally I'd have liked to have seen them shorten the rear end a little as well. Of course, they may have tried the shorter rear and decided against it, leaning towards stability. . . .
    . . . . . . . .

  54. #54
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    Saw this yesterday. I agree with their thoughts that its better to do this with a 27.5 frame versus a 29. Also made sense to choose a bike that has at least a 20mm travel difference between front and back so you could drop the 29 fork travel to get more in line with the original geometry. I like the concept. Time will tell if it catches on.

    https://www.youtube.com/watch?v=ve6gUSJgylwhttp://

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    I just did this to my 29er spec enduro. With the adjustable geometry set in high, the mixed wheel size has roughly the same angles as 29 f/r in low. I'm guessing this is also partially because the factory setup is a 2.3 rear and a 2.6 front tyre. I've decided to run the rear as 2.6 in the mixed setup to offset the smaller diameter.

    Just finished it this week, so can't comment on how it rides.

  56. #56
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    Quote Originally Posted by crembz View Post
    I just did this to my 29er spec enduro. With the adjustable geometry set in high, the mixed wheel size has roughly the same angles as 29 f/r in low. I'm guessing this is also partially because the factory setup is a 2.3 rear and a 2.6 front tyre. I've decided to run the rear as 2.6 in the mixed setup to offset the smaller diameter.

    Just finished it this week, so can't comment on how it rides.
    I just did virtually the same thing to my Fezzari La Sal Peak. It can run 27.5+ with the chip in high mode, or most commonly, 29 in low mode. Initial setup was 27.5+ F/R - high. I am now, as of this week, running 29 x 2.6 front X 27.5 x 2.8 rear, leaving the chip in high. As you mentioned, I'm guessing the geometries are now pretty close to the 29 F/R low mode. The 2.8's and 2.6 are virtually the same width, but the 27.5+ is taller.

    The bike very much came to life with this change. When I first jumped on it in the garage, I was amazed at the change in stability. I could essentially do a seated track stand with no input whatsoever. The first ride in mullet mode was amazing, both up, down, and surprisingly so much better pedaling the flat ground XC style. Climbing did not seem to be compromised at all, in fact I was in a more comfortable position - switchbacks actually seemed easier. The added pedal clearance was noticeable, as the the bb is pretty low in + high chip mode. But the descents, holy crap, were awesome. It was that big of a difference. Front end traction was significantly improved, and it was, for some reason, so much easier to transition the bike's angulation in one turn to angling the other way for the next. In + mode, there was a weird hitch/dead spot that made this transition cumbersome. Now it feels down right nimble, especially for a bike with this long of a wheelbase.

    I went faster, turned faster, used more travel, and it is so much fun. Five months into riding this bike, the first ride a la mullett was the first time the bike felt right.
    I would advise not taking my advice.

  57. #57
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    I modelled it up in bikecad, the difference on a 2.6 rear tyre was .1 slacker hta/sta and about 3mm lower BB height. I use 165mm cranks vs 170 factory so no higher risk of pedal strikes.

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    Quote Originally Posted by scatterbrained View Post
    Personally, I wonder how the Alchemy rides. It looks like they just changed the linkage of the 29er to keep the geometry the same. Personally I'd have liked to have seen them shorten the rear end a little as well. Of course, they may have tried the shorter rear and decided against it, leaning towards stability. . . .
    I didn't look at the geo but that's kinda lame if its basically the 29er with a 27.5 wheel. It seems to me like the one of the benefits to tap into if you are going to design the mullet bike is to throw some shorter chainstays on there or make the bike capable of running wider tires on the rear.

    Although reading the responses after yours the mullet concept still sounds good, its just seems that they are missing an obvious benefit (IF that's the case, but I am assuming they made all the changes they needed to to make the bike good).

  59. #59
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    Quote Originally Posted by agreenbike View Post
    I didn't look at the geo but that's kinda lame if its basically the 29er with a 27.5 wheel. It seems to me like the one of the benefits to tap into if you are going to design the mullet bike is to throw some shorter chainstays on there or make the bike capable of running wider tires on the rear.

    Although reading the responses after yours the mullet concept still sounds good, its just seems that they are missing an obvious benefit (IF that's the case, but I am assuming they made all the changes they needed to to make the bike good).
    From what I read they changed the linkage but the chainstays are the same. I just double checked though and both their 29er and 27.5 bikes run 438mm (17 1/4") chainstays, about one centimeter shorter than the stays on my 29er, but about 1.3cm longer than say, a Transition Scout. still, it's interesting.
    . . . . . . . .

  60. #60
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    Does anyone have a calculator tool to figure the resultant geo changes when making going mullet and any tips?


    Thanks!

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    Conversely, if someone loves doing this stuff, I'm particularly interested in the following:

    I have a '19 Mondraker Foxy 29 with a 42mm offset Yari up front. I run a -1 headset on the bike.

    I'd like to compare the geo on the set up I currently run directly to the same frame, running a 27.5" x 2.5" rear tire, reducing my fork to a 150mm, and both with, and without the -1 headset I currently run.

    Bueller?

  62. #62
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    Quote Originally Posted by Suns_PSD View Post
    Does anyone have a calculator tool to figure the resultant geo changes when making going mullet and any tips?


    Thanks!
    Bikecad

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    https://www.vitalmtb.com/community/t...18/setup,37461

    Downduro build. Nicely done.


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  64. #64
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    Quote Originally Posted by Verbl Kint View Post
    https://www.vitalmtb.com/community/t...18/setup,37461

    Downduro build. Nicely done.


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    I've heard of floating brake rotors, but a floating caliper?!?!!

  65. #65
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    Thinking a spare 27.5" burly rear wheel with a burly rear tire to slap on my 29" trail bike for the rare bike park day would be nothing but beneficial. All upside for that application.

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  66. #66
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    Mtbr.com is going to have to add a new subforum, Mullet Wheel Size!

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    Quote Originally Posted by Suns_PSD View Post
    Mtbr.com is going to have to add a new subforum, Mullet Wheel Size!
    Only if mullets progress beyond the fad stage and enough people ride them...

    I'm kind of excited to see the mullet concept take off though. I just got fully invested in 29er for awhile but have the ability to run a 27.5+ tire on the rear so a mullet might be an option for me.

    Quote Originally Posted by Suns_PSD View Post
    Thinking a spare 27.5" burly rear wheel with a burly rear tire to slap on my 29" trail bike for the rare bike park day would be nothing but beneficial. All upside for that application.

    Sent from my SM-G892A using Tapatalk
    I didn't think of that, that would be a good reason for going with a mullet setup.

  68. #68
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    Quote Originally Posted by agreenbike View Post
    Only if mullets progress beyond the fad stage and enough people ride them...
    I think for that to happen more companies are going to have to design them from the ground up to run the mullet setup. Most times when things are adapted or configured differently then the original design things just don't work quite as well.

    The Stumpjumper, or at least some of them, were designed to run either 27.5 or 29. I never seen anywhere that Specialized intended them to be run as a mullett. So if someone would set them up as a mullet I could see that the results may not be as good as something like a Foes Mixer.

    Speaking of the Stumpjumper vs the Foes Mixer. Last year I was in the market for a new bike. I had a pretty good demo of a Stumpy set up as a 29er. I also rode a Giant Stance 27.5. My old bike was a 2001 Raleigh M600 HT with a RS Judy XC, a 26er of course. I ended up buying a Foes Trail Mixer.

    The Foes outperforms the Stumpy and the Stance in every way. It climbs better, descends better, I can pick my way through a rock garden better, and handles tight corners as well as the 27.5 maybe a little better. I was really impressed with how responsive it is on acceleration when climbing. I really don't think it gives anything up to the HT on acceleration really and it's far better then the Stumpy. The HT might handle tight corners better but not really that much until it gets really tight like maneuvering between trees.

    When I look at how much better it handles then the Stumpy I can't see that I would have gotten the same performance simply by putting a 27.5 on the back of the Stumpy.

    Now it's true that some of the better performance might be due to a better speced bike. The Foes has a better fork and shock then the Stumpy and Stance did as well as wider tires.

    Just my 0.02.

  69. #69
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    Is there a formula or ratio for how the bb will drop if you take a 29er frame and change nothing but going to a rear 27.5 wheel in same width (29x25_>27.5x2.5)

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    I just started a new thread with the below, but it looks like here would have been the better place to ask my question. DL;DR: What is the shortest A2C 150mm travel 29er fork?

    ------------------------------------------------------

    I am looking to mullet out a trail bike and would like to use the fork that will have the least impact on the bike's geometry. Don't get me wrong, I'm fine with raking out the front end and bumping up the bottom bracket. I simply want to minimize those things to the degree that I can.

    The bike is a 150mm front, 140mm rear trail bike designed around 27.5 wheels. The head angle is 67 degrees and the bottom bracket is a 338mm. The frame has a flip-chip that will allow me to steepen the head angle to 67.4 degrees and raise the bottom bracket to 343mm. I would like to keep the front travel at 150mm.

    So two questions for the group:

    -Which non-boutique 150mm 29er boost fork has the lowest axle to crown distance? You would think that this is easy to determine, but I have seen conflicting data. As in, is it really true that A2C on a Fox 36 is significantly less than the A2C on a Fox 34 of the same travel?

    -Are there any 27.5 forks that can accommodate a 29x2.6 DHF? I'm thinking "no," but figured I would throw this out to the group.

  71. #71
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    fox is 5mm lower than equivalent rockshox. both 34 and 36. but probably has less static sag due to RS's stronger negative spring. IOW, close to a wash.

  72. #72
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    Quote Originally Posted by FactoryMatt View Post
    fox is 5mm lower than equivalent rockshox. both 34 and 36. but probably has less static sag due to RS's stronger negative spring. IOW, close to a wash.
    Thanks! It turns out that the internet is full of lies and misinformation because that is not what the interwebs told me. But this doesn't apply to you, FactoryMatt. You're my only hope! (please picture me in a Princess Leia outfit when you read this.)

  73. #73
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    Quote Originally Posted by yetipowdermaniac View Post
    Is there a formula or ratio for how the bb will drop if you take a 29er frame and change nothing but going to a rear 27.5 wheel in same width (29x25_>27.5x2.5)
    Putting a 650b wheel on the back of a 29er bike will lower the rear axle by 19mm, which will slacken the head and seat tube angles by about 0.8 deg and lower the BB by roughly 13mm depending on the rear center to front center ratio.

    Running a 29er fork and front wheel on a 650b bike will raise the front end by about 39mm. The axle to crown length of a 29er Fox fork is 18mm longer than the equivalent 650b fork. The larger wheel also raises the front axle by 19mm, which is equivalent to increasing the axle to crown length by about 21mm (here's the math for that). 18mm + 21mm = 39mm. This will slacken the head and seat angles by about 1.6 deg and raise the BB by roughly 14mm. One advantage to doing it this way is you can offset this effect by reducing the front travel. Every 10mm will steepen the angles by ~0.4 deg and lower the BB by ~3.5mm.

    Some of the best all-mountain bikes I've found for this conversion are the Firebird 29 in the high setting, Foxy 29, 2017 Enduro 29, 2018 Enduro 29 in the high setting, 2019 Megatrail or Shred Dogg with the zero stack lower headset cup, or Instinct/Pipeline in the steepest geometry setting.
    Last edited by dlxah; 08-07-2019 at 10:24 PM.

  74. #74
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    Why do you like the Foxy 29 for this conversion? I have that bike and was considering experimenting.
    Thx.

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    Quote Originally Posted by Suns_PSD View Post
    Why do you like the Foxy 29 for this conversion? I have that bike and was considering experimenting.
    Thx.
    Relatively high BB and steep angles. With 650b in the back, the BB would drop to around 339mm, HA would slacken to 65.2 deg, and SA would slacken to 74.7 deg. Those resulting numbers are still pretty comparable to a lot of other modern, mid-travel 29ers. Granted, that seat angle is a little slack by today's standards, but 74.7 deg really isn't that bad and you could mitigate that a bit by slamming your saddle forward. I don't know if this is possible on that frame, but you might also be able to add some offset shock hardware to extend the shock and raise the rear end back up a tiny bit (which is essentially the same thing most of the bikes with high / low flip chips are doing).

  76. #76
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    Just did this to a 2019 enduro 29 in high setting. From my calculations the geometry mullet in high is not that far off running 29 f&r in low.

    Rode it this past weekend on a more technical xcish trail (which isn't ideal for this bike) and all I can say is I'm sold.

  77. #77
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    Quote Originally Posted by crembz View Post
    Just did this to a 2019 enduro 29 in high setting. From my calculations the geometry mullet in high is not that far off running 29 f&r in low.

    Rode it this past weekend on a more technical xcish trail (which isn't ideal for this bike) and all I can say is I'm sold.
    I bet that bike rips! Got any pictures?

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    Does this thing count?

    The 97.5 AM Bike Thread (29" front, 27.5" rear wheels)-p5pb17300379.jpg

  79. #79
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    Quote Originally Posted by dlxah View Post
    Relatively high BB and steep angles. With 650b in the back, the BB would drop to around 339mm, HA would slacken to 65.2 deg, and SA would slacken to 74.7 deg. Those resulting numbers are still pretty comparable to a lot of other modern, mid-travel 29ers. Granted, that seat angle is a little slack by today's standards, but 74.7 deg really isn't that bad and you could mitigate that a bit by slamming your saddle forward. I don't know if this is possible on that frame, but you might also be able to add some offset shock hardware to extend the shock and raise the rear end back up a tiny bit (which is essentially the same thing most of the bikes with high / low flip chips are doing).
    Thanks for the info.
    One is able to remove the spacer from the 205 x 62.5 shock to get 65mm stroke. I had to add my spacer in because my shock came from a different bike.
    My Foxy runs a -1 headset and it measures 77.4 STA & 65.6 HTA, but that's with no sag I do run the seat all of the way forward but I measure referencing the center of the seat post.

    Sent from my SM-G892A using Tapatalk

  80. #80
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    So I'm planning to order custom geo steel hardtail, mainly for enduro type riding. I was thinking geo to be a mix of taival and moxie. I would like to run rear wheel 27.5" with 2.6" tire (max 2.8") and 29" front with maybe 2.6" tire. Is there anything to consider with the geometry to make it work?

    Taival and moxie have 60/64mm bb drop and I was thinking maybe 50-55mm to compensate the smaller rear wheel. Also seat and head angle will drop a little bit, probably under one degree.

    Is there anything else?

  81. #81
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    Quote Originally Posted by cokratex View Post
    So I'm planning to order custom geo steel hardtail, mainly for enduro type riding. I was thinking geo to be a mix of taival and moxie. I would like to run rear wheel 27.5" with 2.6" tire (max 2.8") and 29" front with maybe 2.6" tire. Is there anything to consider with the geometry to make it work?

    Taival and moxie have 60/64mm bb drop and I was thinking maybe 50-55mm to compensate the smaller rear wheel. Also seat and head angle will drop a little bit, probably under one degree.

    Is there anything else?
    I would try to think in terms of BB height rather than BB drop. BB drop gets pretty confusing when you have two different wheel sizes. Would it be the drop relative to the rear axle or the front axle? Or perhaps it's the drop relative to an imaginary line from the rear axle to the front axle, and if that's the case, then things start to get really messy.

    Other than that, the geometry should be the same as any other bike. A good frame builder can account for the mixed wheel sizes, so all you have to worry about is what geometry you want the bike to have with the mullet wheels.

    Edit: Since neither the Taival nor Moxie list a BB height, I'll add that most manufacturers use about 370-375mm as the height of a 29" wheel + tire. So a BB drop of 60mm would be about a BB height of 310-315mm, and a 64mm drop would be a height of 306-311mm.

  82. #82
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    Quote Originally Posted by crembz View Post
    Just did this to a 2019 enduro 29 in high setting. From my calculations the geometry mullet in high is not that far off running 29 f&r in low.

    Rode it this past weekend on a more technical xcish trail (which isn't ideal for this bike) and all I can say is I'm sold.
    Can you elaborate a bit on your thoughts about the mullet setup in techy XC? I'm intrigued by the concept but as 90% of my riding falls under the category you mentioned I thought there is nothing to gain there compared my current setup of 29x2.6 F+R. At least I know I don't want anything that hinders steep technical climbing.

    Then again as my Fuel EX started off as a 27.5+ and I have the plus wheelset collecting dust I'm toying with the idea of putting a burly 27.5x2.8 on the rear for the occasional bike park days.

  83. #83
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    Quote Originally Posted by TimoA View Post
    Can you elaborate a bit on your thoughts about the mullet setup in techy XC? I'm intrigued by the concept but as 90% of my riding falls under the category you mentioned I thought there is nothing to gain there compared my current setup of 29x2.6 F+R. At least I know I don't want anything that hinders steep technical climbing.

    Then again as my Fuel EX started off as a 27.5+ and I have the plus wheelset collecting dust I'm toying with the idea of putting a burly 27.5x2.8 on the rear for the occasional bike park days.
    Honestly I think it has more to do with the rider than the bike.

    I'm short (168cm), I find 29ers never fit me right. I like how they steamroll terrain, how they climb but I don't get the movement I want out of them downhill, over jumps and down drops, my arse is constantly hitting the rear and wishing I could get farther back. The Mullet gives me a 29er in a package that fits me better and that I can wrangle around easier.

    If I was taller I'd probably never have done a mullet and just settled with a 29er. IMO based on the bikes I've owned and ridden:

    29 = tall people
    mullet = short people
    27.5 = I don't see the benefit of this over a mullet other than lower cost, don't need to buy wheel/tyre/fork

    Just personal option I'm sure people will disagree.

  84. #84
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    Quote Originally Posted by dlxah View Post
    I bet that bike rips! Got any pictures?
    There she is, Enduro Comp 29 Mullet

    The 97.5 AM Bike Thread (29" front, 27.5" rear wheels)-img_20190809_104723.jpg

    And My Nukeproof Scout 275 Mullet

    The 97.5 AM Bike Thread (29" front, 27.5" rear wheels)-img_20190809_104734.jpg

  85. #85
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    Quote Originally Posted by dlxah View Post
    I would try to think in terms of BB height rather than BB drop. BB drop gets pretty confusing when you have two different wheel sizes. Would it be the drop relative to the rear axle or the front axle? Or perhaps it's the drop relative to an imaginary line from the rear axle to the front axle, and if that's the case, then things start to get really messy.

    Other than that, the geometry should be the same as any other bike. A good frame builder can account for the mixed wheel sizes, so all you have to worry about is what geometry you want the bike to have with the mullet wheels.

    Edit: Since neither the Taival nor Moxie list a BB height, I'll add that most manufacturers use about 370-375mm as the height of a 29" wheel + tire. So a BB drop of 60mm would be about a BB height of 310-315mm, and a 64mm drop would be a height of 306-311mm.
    Was thinking exactly this, i have been playing with bikecad and I can only enter bb drop, but in the final result I see the height.

  86. #86
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    It's the difference in drop the you feel on the trail. The height determines how much stack height you need and the ground clearance you have, but it's mostly the drop that influences how a bike handles. Also, drop is much easier to use in calculations, because it is calculated from the imaginary line connecting the axles. As long as the wheel sizes and tires have the same diameter, the drop remains constant. Posting bottom bracket height would be useless without knowing specific tire height, rim width, tire pressure, etc. None of that changes the drop, assuming front and rear is similar. Of course, changing to a mullet setup will make things more difficult, but again, it is easier to calculate drop than height.

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    Quote Originally Posted by cokratex View Post
    So I'm planning to order custom geo steel hardtail, mainly for enduro type riding. I was thinking geo to be a mix of taival and moxie. I would like to run rear wheel 27.5" with 2.6" tire (max 2.8") and 29" front with maybe 2.6" tire. Is there anything to consider with the geometry to make it work?

    Taival and moxie have 60/64mm bb drop and I was thinking maybe 50-55mm to compensate the smaller rear wheel. Also seat and head angle will drop a little bit, probably under one degree.

    Is there anything else?
    You might want to consider a bike designed explicitly for this set up...

    https://www.singletracks.com/blog/mt...et-honeymaker/

    Or, better yet, get the original Mike V full production mixed wheel bike, designed from the ground up for this set up...

    https://www.pinkbike.com/news/foes-m...view-2016.html

    https://mbaction.com/foes-mixer-enduro-test/

    It really is about more than the minutia of angles and millimeters being kicked around on this thread. Like any high end bike, it's the sum of the parts. You really have to ride one. Cheers,

    E

  88. #88
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    Quote Originally Posted by mountainbiker24 View Post
    It's the difference in drop the you feel on the trail. The height determines how much stack height you need and the ground clearance you have, but it's mostly the drop that influences how a bike handles. Also, drop is much easier to use in calculations, because it is calculated from the imaginary line connecting the axles. As long as the wheel sizes and tires have the same diameter, the drop remains constant. Posting bottom bracket height would be useless without knowing specific tire height, rim width, tire pressure, etc. None of that changes the drop, assuming front and rear is similar. Of course, changing to a mullet setup will make things more difficult, but again, it is easier to calculate drop than height.
    While I agree that BB drop does influence how a bike handles out on the trail, most bikes are actually designed around BB height. You generally want the lowest BB height you can run without the pedals or the chainring hitting things too often. If you look at some geometry tables, you'll notice that most bikes of the same intended purpose and similar amounts of travel have similar BB heights regardless of wheel size. The Hightower and Bronson are both about the same BB height despite the Hightower having ~19mm more drop. Same with the Endruo 29 and 650b versions, or the SB130 and SB140, or really the vast majority of bikes I've looked at.

    I'd also argue that BB height is a much better basis for comparison between bikes especially when the wheel sizes are different. BB height is a personal thing that depends a lot on your riding style, the trails you usually ride, and just personal preference, but BB drop is not personal. We all want the most BB drop we can have, but prefer different BB heights largely due to our tolerance for pedal strikes or smashing chainrings. Because of this, the BB height you prefer with one wheel size will probably be about the same BB height you would prefer on another wheel size (all else being equal) despite a significant difference in BB drop.

    And in this case where we're talking about having a custom frame made, who cares which one is harder to calculate? Just tell the frame builder what BB height you want and let them worry about that stuff (e.g. "I want the BB height to be the same as my current bike at sag" or 5mm lower or whatever). Easy.

  89. #89
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    Bottom bracket height is just not a practical measurement, because there are so many factors involved with the measurement. Drop takes most of those factors out of the equation, making it easier to compare bikes. I mean, yes, you can tell a builder that you want a certain bottom bracket height with a specific fork, wheel size, rim and tire, but It's the drop measurement that the builder is going to need.

  90. #90
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    It seems bikecad measure bb drop from horizontal line from rear axle when I put different front and rear wheel diameter.

    I agree bb drop is easier to use when talking numbers, but the bb height you end up with is what matters when you are riding. I guess it is a compromise, as low as possible but with reasonable crank clearence.

  91. #91
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    Just plain fun!

    No technical mumbo jumbo here.
    Stock is 27.5 front with 170mm travel. Was nice. Not a 27.5 fan. Swapped out my 160mm Fox 36 off my other bike and threw on a 29r front and Bam!
    The lower travel and bigger tire equals same geo but with better rollover.
    No hype or passing trend.......
    Just plain and simply more enjoyable.

    The 97.5 AM Bike Thread (29" front, 27.5" rear wheels)-b1dae00a-4412-4876-9f7a-7ac3cb2f8e58.jpg

  92. #92
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    I have done a couple of mullet set-ups, one on a scott genius and one on a specialized stumpy evo, put together a build video here with some detailed numbers and ride impressions - https://www.youtube.com/watch?v=B7DCGLUbJvw

  93. #93
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    Quote Originally Posted by Broads72 View Post
    No technical mumbo jumbo here.
    Stock is 27.5 front with 170mm travel. Was nice. Not a 27.5 fan. Swapped out my 160mm Fox 36 off my other bike and threw on a 29r front and Bam!
    The lower travel and bigger tire equals same geo but with better rollover.
    No hype or passing trend.......
    Just plain and simply more enjoyable.

    Click image for larger version. 

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    Nice one! I agree I've found it just more enjoyable. If you have the parts it's definately worth a try.

  94. #94
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    Now intense offers their trailbike in 29er, 27.5, and, you guessed it, "mullet" 97.5: https://www.pinkbike.com/news/intens...look-2020.html

    Now that major manufacturers are starting to get into the mullet craze, it will be interesting to see if they take off in the next few years or if they fizzle out like when 27.5+ bikes came onto the scene and were the future for 1-2 years then just kinda died off.

  95. #95
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    Unfortunately, that Primer S (mullet) appears to just be a Primer 29 frame with a 650b wheel in the back. It doesn't look they did anything to correct the geometry for the smaller rear wheel. It's got a 73.5-74.1 deg seat angle and a super low 327-334mm BB height. All of the bikes I mentioned in my previous post are better candidates for a mullet conversion than the new Primer 29, unless you like a relatively slack seat angle and low BB.

  96. #96
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    Not to mention that it is using a 27.5x2.8 rear tire. I'm waiting for someone to design a proper FS trail/enduro bike with regular 27.5 and 29 tires and a frame that was engineered from the ground up around the 97.5 concept. Oh, and I want it in carbon.
    . . . . . . . .

  97. #97
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    I recently borrowed a wheel and tried the mullet on my '17 Giant Trance, size large frame with a Rock Shox Super Deluxe RCT shock and a DVO Diamond 29 Boost fork, 140mm travel front and rear.

    The 27.5 setup:
    Front: 27.5x2.8 DHF on a 35mm-internal rim
    Rear: 27.5x2.6 Forekaster on a 35mm-internal rim
    Front Axle Height: 360mm
    BB height: 343mm


    The mullet setup:
    Front: 29x2.6 Forekaster on a 29mm-internal rim
    Rear: 27.5x2.6 Forekaster on a 35mm-internal rim
    Front Axle Height: 382mm (+22mm)
    BB height: 350mm (+7mm)


    The Results:
    I found that with the 29x2.6 front tyre the bike rolled well, a lot like my 29er, and the it mostly felt good. However, I found the steering was sometimes awkward. On low-speed switchbacks the steering would initially feel fine, but at some point mid-turn the steering would flop and turn more quickly than I intended. I suspect this may be related to the 51mm offset of the DVO fork. Other than that, I thought the bike felt a bit off (too tall?) with the shock in threshold/platform, but felt nice with the shock open. In the end, I've decided to keep the 27.5 front wheel.

    Ive been swapping between 2.4, 2.6, and 2.8 tyres on the 27.5 rims. The 2.8 DHF is a bit much, so Im sizing down to a 2.6 DHR2 on the front and keeping the 2.6 Forekaster on the back, for now.

    27.5:
    The 97.5 AM Bike Thread (29" front, 27.5" rear wheels)-275.jpg

    The 97.5 AM Bike Thread (29" front, 27.5" rear wheels)-275bb.jpg

    29:
    The 97.5 AM Bike Thread (29" front, 27.5" rear wheels)-29.jpg

    The 97.5 AM Bike Thread (29" front, 27.5" rear wheels)-29bb.jpg
    Dave

  98. #98
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    Anyone could fit a 27.5x3.0 in a alloy Genius (rear)?

  99. #99
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    an alloy

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    ... and if we just ...

    Here is an article of interest,

    https://www.notubes.com/news/staff-b...t-in-progress/

    I'm don't agree about 29ers not being as good a candidate for conversion, I've done 27,5's and 29ers. My latest is a 29er and it has turned out great.

    It all depends on the bike and what you get out of it.

  101. #101
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    I agree. I have a 29 specialized enduro, I could not get it to handle pace or steep terrain. And it cornered like a cow. I had trouble getting behind it and wieght off the front wheel. Which felt dangerous as. I Put a 27.5 on the rear and the bike came to life, it now handles the big hits and the pace confidently. The bb is as low as my old 26" which is low but it doesn't hit anywhere so I can deal with that.
    I didn't like the bike before the mod. The reverse reverse worked for me.

  102. #102
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    I recently had the opportunity to ride and do a quick review of the Mullet honeymaker. Unfortunately the geo wasnt quite what I was hoping for, but I applaud mullet for thinking outside the box. And they sure know how to make a great looking bike.


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