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  1. #1
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    2007 Prophet 4 twisty rear end ?

    Ok since I've owned my Prophet "traded in my Jeykll which I loved" I've had nothing but problems from the rear end. It started with the rear brake always rubbing to it GHOST shifting constantly. Well today I'm riding at my favorite spot and in the parking lot is a Titus factory truck with demo bikes sponsored by Speedgoat bike shop. I show the guys at the truck how the rear wheel is not perfectly lined, it's twisted to the left like the right side of the swingarm is shorter than the left. One of the guys grabbed the rear wheel and twisted it side to side. I could not believe the amount of flex !!! I did this than grabbed a Moto Lite which had zero side flex. Now did I get a bad rear section or are all Prophets made this way and if so WHY !!!!!! I so want my Jeykll back, Anyone with info on this I encourage you to e-mail me at mcornell@iup.edu
    The bike goes back to the shop tomorrow and I imagine my LBS owner will feed me a line of crap.
    If it's supposed to be flexy I can handle that but the ghost shifting got to go.

  2. #2
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    Had the ghost shifting and rear end flex on my prophet also. Ran a full length shift cable housing to the rear and the ghost shifting was fixed. Prophets do have lateral flex in the rear. I never was a fan of it, but got used to it. Even the MX versions have similar lateral flex, even with a thru axle in the rear. Never did have a prob with the rear end twisting though. The bike was great for trail riding and doing some jumping and dropping, but the lateral flex was always apparent. Could definitely feel it on fast corners and off camber landings. Other than that, I really like the bike. Just had to move on to a bigger bike as I progressed.

  3. #3
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    Interesting. I can feel a bit of wiggle when I hit an off camber step-up at just the right angle. It sure feels like the back is moving around. I don't have any ghost shifting issues, but I can coast along and lean the bike from side to side and get the rear disc to drag on the pads. Kinda surprising really. Good thing the bike is so great to ride otherwise or I would be bummed.

    Wonder where all the flex is coming from? Seems like it would be pretty stout by looking at it.

  4. #4
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    The twist

    Considering that the rear upper swing arm is connected directly to the shok - which is un supported - I can see where the flex would be coming from. I just don't understand why with such a stout front triangle that the rear upper pivot was not beefed up ? Anyway anyone else notice if the rear wheel is off camber in the swingarm ?

  5. #5
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    Noodle

    My Prophet is flexi as hell ...I am 180lbs and the back end is the worst part of the bike a big disappointment TBH ....Try following your prophet and watch the back wheel then watch a Reign or Nomad or some other stout ended bike and you can really see the difference in the way the back end reacts

  6. #6
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    Interesting. I wonder why I don't hear this about the SC Hecklers? Seems like they would be the same.

    Maybe they are built heavier in the frame construction. They sure seem to build up a few pounds more than my Prophet.

    I remember following a guy in the club (Clydesdale) on his Prophet and his back wheel was definitely doing a bit of the mambo. Still, I don't feel a loss of steering precision or anything when I ride hard.

    Well, I guess no bike is perfect, but in the two weeks I have been riding, I sure have been impressed by the bike.

  7. #7
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    Good job! Wiggly rear

    I fixed my flexing rear end with a Chris King rear hub with the fun bolts kit and a much stiffer rim. The mavic crosslands that came with the bike are junk in my opinion. The change is dramatic. For heavier ridders this upgrade is well worth the $$$.

  8. #8
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    This is interesting, because I've heard a lot of people talk about flex on the rear end of prophets... That it's usually the main reason people don't buy it.

    In the time I've had mine, I haven't really done any hardcore riding, to notice it...

    PS. I've heard that they might build flex into it, to increase durability... As the stiffer it is the more likely it is to snap? Someone correct me if I'm wrong...

  9. #9
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    Quote Originally Posted by BMP808@comcast.net
    I fixed my flexing rear end with a Chris King rear hub with the fun bolts kit and a much stiffer rim. The mavic crosslands that came with the bike are junk in my opinion. The change is dramatic. For heavier ridders this upgrade is well worth the $$$.

    What is the fun bolts kit?

  10. #10
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    Best thing I ever did was upgrade my wheels to XM819 rims on hope Pro IIs, really stiffened that back end up.
    I think the Prophet is an incredibly well balanced bike, just flows nicely. Can't say I notice any flex as such, it feels like it's working just right to me.

  11. #11
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    I thought I'd best add that I'm 12.5 stone, so I'm not sure how it holds up with bigger guys.


  12. #12
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    It may sound stupid, but I feel it only when I'm running at too low air pressure (<30 psi) - indicative that it is not the bike but the large (2.35) tires (Spyders, High Rollers, Nevegals)that are flexing. When properly inflated, it just isn't a problem. I've got a Prophet 2000 with 819's and a somewhat burleu Hope Bulb rear hub. I watch the spokes too.

  13. #13
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    I've felt mine flex a little when slipping in and out of ruts but thats about it. I've never felt it deflect from rocks etc. I've also never had it ghost shift or flex so the brake drags and I'm 210#.

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    Have anyone trie taking off the rear wheel and compressing the chainstays? Or twisting one up and the other down at the same time? Maybe also secure the bike so that you can rotate the swingarm from one side to the other?
    My experience from forks is that the spaghetti ones are possible to flex by arm strength alone. I haven't tried with my prophet.
    Personally, my bike felt stiffer when I got a Hope II with x819 (32 spokes) wheel.

  15. #15
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    On with the show.

    Ok took bike to shop and explained problem. I showed how flexy the rear end was (not the wheel it was off) and I showed him how the drive sidfe of the swingarm is at least an eighth inch shorter than the brake side. This was measured from two points. From the center of the bb to the rear axle and from the center of the main swingarm pivot to center of rear axle. Hence the rear wheel sitting off centered in the swingarm ! He was on the phone with Cannodale and they gave him BS that the whole frame is set in a jig prior to being welded and that it could not be off from that. However the tech could not answer if it was made to be that way. That was Monday 6-2-07 Today 6-3-07 got a call to come pick up bike that the "ghost" shifting was cured by a fully jacketed shift cable. I asked about the rear end and was told (by the shop owner my friend) that he still needs to talk to Cannondale about the mis alignment. I told him to keep the bike untill it was fixed. I paid close to $2000. for a bike and I want it to work better than a wal-mart brand. I also have an old Schwinn Homegrown hardtail. Never a problem don't think I ever even had a flat on it.
    I'll ride it !!!!!!!!!!!!!!

  16. #16
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    When I bought my 05 Prophet 1000 one of the first things that I noticed Is that when I applied any lateral forces to my bike like hammering short climbs with some body english applied the rear tire would rub the swing arm. I attribute this to the Mavic Crossland wheels flexing under the forces. The cheep fix was to run a smaller 2.0 tire. The more time I spent on the bike the more I noticed the rear swing arm flexing on trails with angled 3 to 4 inch roots or going over logs that I hit at an angle. I weigh 220lbs. so lighter riders will probably not notice as much flex as I do. What I eventually did to cure my situation was not to go on a diet but I bought a Chris King rear hub. The hub has a Fun Bolts kit which substitutes bolts for the quick release. THIS MAKES A HUGH DIFFERENCE! With the Chris King hub you also get a 72 tooth ring gear engagement instead of a two pawl engagement which comes in all Mavic free hub bodys which I was replacing every 6 months at $50 bucks a pop. I spent $400 for the hub with the fun bolts spent $25 for spokes and nipples and $25 for a rhino rim and built the wheel myself. Now I have the firmest rear in town. This is the best money I've ever spent on a bike.

  17. #17
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    I fixed my Prophet

    Had similar problem with my Prophet 1000. Fixed it by buying a Turner 5-spot!!!

  18. #18
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    Quote Originally Posted by BMP808@comcast.net
    When I bought my 05 Prophet 1000 one of the first things that I noticed Is that when I applied any lateral forces to my bike like hammering short climbs with some body english applied the rear tire would rub the swing arm. I attribute this to the Mavic Crossland wheels flexing under the forces. The cheep fix was to run a smaller 2.0 tire. The more time I spent on the bike the more I noticed the rear swing arm flexing on trails with angled 3 to 4 inch roots or going over logs that I hit at an angle. I weigh 220lbs. so lighter riders will probably not notice as much flex as I do. What I eventually did to cure my situation was not to go on a diet but I bought a Chris King rear hub. The hub has a Fun Bolts kit which substitutes bolts for the quick release. THIS MAKES A HUGH DIFFERENCE! With the Chris King hub you also get a 72 tooth ring gear engagement instead of a two pawl engagement which comes in all Mavic free hub bodys which I was replacing every 6 months at $50 bucks a pop. I spent $400 for the hub with the fun bolts spent $25 for spokes and nipples and $25 for a rhino rim and built the wheel myself. Now I have the firmest rear in town. This is the best money I've ever spent on a bike.
    Interesting. I really cannot stand the noise a King hub makes...I don't care how good it is, but I know they are great hubs. They sound like a big Cicada.

    But besides that, the Crossland wheel sets...are those what is on an 800? I dont see that labeled anywhere. they are a Mavic rim, but besides that...not sure.

    I don't have anywhere near that kind of flex. Mercy.

  19. #19
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    Hows this happen ????

    Waiting for my bike to come back from bike shop. Was told today that he is waiting for a new swingarm from Cannondale and was also told that Cannondale "had to make one"!!!!
    How can this be. It's a multi produced bike shouldn't they have a stack of swingarms hanging around ????? Or am I being fed BS ????
    I'm still out a bike.

  20. #20
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    Yes!

    Quote Originally Posted by daktari
    Have anyone trie taking off the rear wheel and compressing the chainstays? Or twisting one up and the other down at the same time? Maybe also secure the bike so that you can rotate the swingarm from one side to the other?
    My experience from forks is that the spaghetti ones are possible to flex by arm strength alone. I haven't tried with my prophet.
    Personally, my bike felt stiffer when I got a Hope II with x819 (32 spokes) wheel.
    Yes i have a spare swinging Arm (due to warranty)and it will flex horizontally, but i can detect no vertical flex, however it takes little wear to produce a twisting motion in the pivots.
    Last edited by mzungo; 07-14-2007 at 11:05 AM.

  21. #21
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    Quote Originally Posted by mzungo
    Yes i have a spare swinging Arm (due to warranty)and it will flex horizontally but i can detect no vertical flex however it tkaes little wear to produce a twisting motion in the pivots.
    I just read a review from the first presentation of the Prophet from winter 05. It stated that Cedrig Gracia thought the bike was to stiff initially, and it would have better traction in curves when there was some flex in the rear. That is what they have done.
    Maybe someone with friends at Cannondales could confirm if this is true?.

  22. #22
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    Quote Originally Posted by mtroy
    What is the fun bolts kit?
    Fun Bolt kit is a kit that converts the QR to a bolt on axle. This is only for Chris King rear hubs.

    There are other hubs like the Shimano XT that can be ghetto converted that works really good.
    Last edited by racerzero; 07-14-2007 at 12:19 PM.

  23. #23
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    No need for ghetto.

    A standard threaded axle can be put in an XT hub. With a nice set of nuts/ washers, it can look really nice and clean.

  24. #24
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    ... and if we just ...

    Quote Originally Posted by 77BMX
    No need for ghetto.

    A standard threaded axle can be put in an XT hub. With a nice set of nuts/ washers, it can look really nice and clean.
    By Ghetto I mean:

    jury-rigged, improvised, or home-made (from Slang Dictionary)

    I also like to use the Ghetto BMX tubeless method. And yes it can look Ghetto if you're lazy. I prefer a clean look so you can't even tell that I'm running tubeless.

  25. #25
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    My Prophet flexed like hell until... I changed the rear wheel for an Atomlab GI hub / Sun Mtx. This hub comes with thru-bolt axle and industrial bearings (unlike the ghettoed Smano) that fixes the swingarm flex. The MTX S-Type rim is 35mm wide that fixes the tire squirm on big volume tires. The rim is much stiffer on itself as well. Cost me 120dollars at Chainreaction. Now my bike feels like running on rails.
    www.swotch.com - Tenerife Island Trail Web

  26. #26
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    Try this !

    Hold you bike upright standing by the seat and reach over to the opposite side, and with the bottom of you closed fist thump the side wall of your tire towards you ...Look at the flex in the rear ...now do the same with the front!...

    Now go and do the same to some of your friends bikes ..and note the results....i found it quite surprising.

    Just ordered a bolt through kit for my Hope Pro 11 hub hope it helps.

  27. #27
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    Prophet - Orange5 flex?

    I haven't noticed any problems while riding my Prophet 2 but you can sure see the flex by grabbing the wheel and pulling from side to side.

    I wonder if Orange5 riders have the same problems as the 2 bikes are very similar in design.

    I've just come back from a week in the French Alps and the bike performed very well. If the flexy rear end causes any problems I didn't notice. Well not until the main pivot bolt came loose but that is another story

  28. #28
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    Mcornell, what is the latest with your Prophet?
    What do I know, ask the "experts"!

  29. #29
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    u can just hold the bike at an angle and step on a petal. with some body weight u can make the rear end flex.
    i get the ghost shifting and rear brake rub on my prophet

  30. #30
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    Quote Originally Posted by Chris85xlt
    u can just hold the bike at an angle and step on a petal. with some body weight u can make the rear end flex.
    i get the ghost shifting and rear brake rub on my prophet
    I put in the Atomlab GI hub in, this is a thru-bolt hub. Much less flex.
    www.swotch.com - Tenerife Island Trail Web

  31. #31
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    Quote Originally Posted by lonbalz
    Even the MX versions have similar lateral flex, even with a thru axle in the rear.
    I haven't noticed any lateral flex on my MX. Never had any ghost shifting or brake rotor rub (and I run 8" rotors). The thru-12 axle setup is plenty stout if setup properly and used in combination with a strong wheel. No complaints here and I am still running the stock hub and rim (spokes have been replaced though). Soon I will be moving to a DT Swiss 340 rear hub for the better engagement mechanism.

  32. #32
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    Just a suggestion, I know you'd lose your adjustable geometry, but couldnt you get an '08 Rush swingarm that has the chainstay bridge or would this not really help with the flex?

  33. #33
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    Does the '08 Prophet have the chainstay bridge?

    -Steve in NJ

  34. #34
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    Im not 100% sure but i dont think it does have a chainstay bridge

  35. #35
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    I had a new swing arm approx a year and a half ago, it took 6 weeks to come!!! said it was being sprayed/ decals etc.

    Also had another new one ( a new re-designed swing arm ) about 3 months ago and that one came in just one week.

    Maybe its because of the colour scheme on your bike?, If its last years colours they may not have them lying around in that colour.

    http://www.27gears.com

  36. #36
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    Why did you need 2 new swing arms? a new re-designed swing arm? Do you know which model year introduced this new re-designed swing arm?
    What do I know, ask the "experts"!

  37. #37
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    The first one was a creaking/ clicking swing arm when under pedaling pressure, either seated or out of the saddle. this was before Cannondale knew about this 'Cannondale tech note'

    Read the note above and it will explain all (note the date, 2005)

    They sent me another Non fix swing arm which lasted approx 1 yearish then it to started to do the clicking noise again I checked the number printed on the swingarm and sure enough it was one of the non fix swing arms.

    So now I have one of the supposed Fixed swing arms? I'll update this in approx 11 months time when it is a year old

    Hope this helps?

    www.27gears.com/news.html

  38. #38
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    Prophet rear flex

    I bought a Prophet for a trip to the alps & the trail parks we have here in the UK. But the rear end flex was so bad, I've recently bought an Ibis Mojo to replace it. Ghost shifting up and down was the norm. Rocky climbs I can clean on my Rush Carbon, I failed on the Prophet, as the rear end just skips out. It had to go..............Why Cannondale don't use the chainstay brace, as on the Rush I just don't know............

    Having had 5 Cannondales this is a big deal for me. I still love my Rush Carbon. I've managed to mount my Lefty Max Carbon 140 on the Ibis, and am in the process of building it up - at least the bike is part Cannondale !

    Laurence

  39. #39
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    Would Saint hub with 10mm axle reduce the flex? A wheelset with this hub goes incredibly cheap at Jansen:

    http://www.jensonusa.com/store/produ...s+Wrr+Der.aspx

    Buy it through mtbr link to sponsor this site: http://www.mtbr.com/hotlinks/
    What do I know, ask the "experts"!

  40. #40
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    how do you like the ibis mojo compared to the carbon rush, that would be a nice shootout! post some pics of that mojo with that lefty please...

  41. #41
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    Quote Originally Posted by david8613
    how do you like the ibis mojo compared to the carbon rush, that would be a nice shootout! post some pics of that mojo with that lefty please...
    you can actually find a picture of it on ebay, just search for lefty adapter or something like that. Looks pretty nice.

    in regards to the main topic, maybe some of those awesome dt swiss ratcheting skewer/axles could do the trick? I think you have to use, Hope or DT-swiss hubs though.

  42. #42
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    How about welding 1lb of aluminum tubing?

    Seriously, Prophet medium frame is 5.25lb (+0.5lb for some shock = 5.75lb) with no shock and for a comparison 18" Kona Dawg with a shock is 8lb. Yeti 575 medium Aluminum-Carbon is at 6.20 lbs (with a shock?). Super flexible Haro Xeon with no shock is at 6.5lb.

    I did not realize that Prophet frame is so light until this moment. Well there is always something new.
    Last edited by ozvena; 12-07-2007 at 08:39 PM.
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    yeah I realized that yesterday while browsing the site...hopefully that upcoming prophet replacement will be built a bit more rigid and AM-friendly

  44. #44
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    Quote Originally Posted by ozvena
    How about welding 1lb of aluminum tubing?

    Seriously, Prophet medium frame is 5.25lb (+0.5lb for some shock = 5.75lb) with no shock and for a comparison 18" Kona Dawg with a shock is 8lb. Yeti 575 medium Aluminum-Carbon is at 6.20 lbs (with a shock?). Super flexible Haro Xeon with no shock is at 6.5lb.

    I did not realize that Prophet frame is so light until this moment. Well there is always something new.

    that surprises me!


    heh, i bet if it wasnt flexy every1 would be *****ing about how heavy it is.

  45. #45
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    Two pages thread and no one pointed it out? I did so much reading about Prophet and did not find that Prophet is a superlight on steroids (or as the author below pointed out: the lightest longest travel bike in its class).

    An interesting article here: The first two hours was spent listening to the Designers, Testers and Engineers waxing lyrical about the hydroformed tubing, balance of the bike being perfect, the 10 months of testing with Cedric Garcia to get the swingarm flex right. It is clear that they have put a huge amount of effort, research and passion into this bike to produce the lightest longest travel bike in its class.

    Sound like a good thing? I wish we could go there for that info too.

    Also this: MISS: Slightly flexy in hard cornering

    Seeing the frame weights now this all make sense. Well, we can use beefier rear hub with no weight penalty against heavier bikes or build it as super light XC, AM capable bike.

    I vote for this to be Cannondale's most kept secret.
    What do I know, ask the "experts"!

  46. #46
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    Mojo v Carbon Rush

    Quote Originally Posted by david8613
    how do you like the ibis mojo compared to the carbon rush, that would be a nice shootout! post some pics of that mojo with that lefty please...
    I should finish the cable-ing up of the Mojo today. I'll post something next week. Obviously travel-wise & wight-wise they are very different bikes. The Mojo is a work of art. I wish I'd applied " 'Copter tape" to the Rush when I first got it. Carbon bikes end up looking tatty too quickly............

    Laurence

  47. #47
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    Swing arm nut is at the spec torque. Rear wheel with Saint hub with 10mm axle was purchased to deal with the issues described in this thread however...

    I am climbing a small hill with brakes applied to simulate a very steep climb:
    http://s87224782.onlinehome.us//frame/tough-hill.wmv

    Here I was going down the hill, flat and slightly up on the big ring:
    http://s87224782.onlinehome.us//fram...lat-uphill.wmv

    The cam was mounted on the top tube.

    What is happening? Is the seat/top tube flexing or everything else including the bottom bracket (just point the cursor at the crank's big ring when playing the videos)? Is this specific to my frame, all Prophet frames or all AM frames?
    Last edited by ozvena; 01-13-2008 at 09:13 PM.

  48. #48
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    nice video

    Quote Originally Posted by ozvena
    Swing arm nut is at the spec torque. Rear hub is saint with 10mm axle to deal with the issues described in this thread however:

    http://s87224782.onlinehome.us//frame/tough-hill.wmv

    I am climbing a small hill with brakes applied the same I see when I just pedal on flat (but less rocking).

    May I ask for your opinion here? What is happening? What is needed if anything? Thanks!
    Bicycles without a seatstay/shock linkage will have a twisty rear end relatively. But, laterally, the Prophet should be stiffer than bikes with smaller chain stays because its swingarm is so massive.

    Seat stays do nothing to help lateral stiffness. They only reduce twisting between the wheel and seat tube. Like when you hold the wheel of an Ellsworth and the seat and twist, there will be very little flex. BUT, is it better to have less twist than lateral flex??

    What you are seeing in the video is the swingarm move side to side (twisting)under the torque of your pedal stroke while your butt holds the seat tube in place. If you where to ride the same hill out of the saddle, you would notice much less movement. There would still be a little movement because of the torque you would place with your upper body on the handlebars.

    BTW, because of the design of the Prophet, the flex is much more visually noticable - because the swingarm and the seat tube are in such close proximity.

  49. #49
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    Quote Originally Posted by ozvena
    Swing arm nut is at the spec torque. Rear wheel with Saint hub with 10mm axle was purchased to deal with the issues described in this thread however...

    I am climbing a small hill with brakes applied to simulate a very steep climb:
    http://s87224782.onlinehome.us//frame/tough-hill.wmv

    Here I was going down the hill, flat and slightly up on the big ring:
    http://s87224782.onlinehome.us//fram...lat-uphill.wmv

    The cam was mounted on the top tube.

    What is happening? Is the seat/top tube flexing or everything else including the bottom bracket (just point the cursor at the crank's big ring when playing the videos)? Is this specific to my frame, all Prophet frames or all AM frames?
    That's quite shocking to actually see in action.

    It almost looks as though the whole BB and down tube is flexing with it whilst the seat tube & top tubes stay still

  50. #50
    mtbr member
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    Jan 2007
    Posts
    1,579
    alot of bikes move more than that, though. I saw a video (i think youtube) of a trek ex(06 or 07) that was flexing alot laterally, even from a further-out POV on easy terrain

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