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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.
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  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.
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  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/
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  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 09:39 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 10:13 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
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    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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    I've read about it, but seeing is believing. I've never felt any kind of twisting or movement from my swingarm. I mean, I thought you'd have to be a really hard core rider to exert the types of loading that would cause this, but from the video the riding seems pretty benign.

    For what it's worth, older (or less sophisticated) motorcycle swingarm designs only have a single pivot and I would be mortified if I saw that much movement.

    It looks more like the swingarm is rocking laterally at the pivot point vice a twisting moment of the swingarm itself. In other words, it looks loose at the pivot point. I say this because if it was the actual swingarm twisting, you'd think you would not see the gaps on either side of the seat-tube opening and closing in unison. Twisting would cause one side to open, while the other gap gets tighter.

    In fact, I would think that a solid rear axle might make this problem worse by transmitting all the force through pivot point vice letting the rear of the swingarm absorb some of the energy by *slightly* twisting

    Whether it be the bearings being loose in the swingarm, the through-bolt being loose in the bore, or the through-bolt being loose inside the swingarm bearings would be hard to tell. Heck, it might be a combo of all three things. I would think if that giant "oh jesus" bolt that links the swingarm through the frame is even a little undersized, it would cause all kinds of lateral flexing. I suppose too that if the cartridge bearings were getting a little sloppy through wear, it would manifest itself in the same kind of "loose" behavior.

    Has anyone ever taken a "loose" swingarm and measured the fit of the bolt in the bore, or bolt and bearing fit? From a purely hypothetical standpoint, if a solid bronze bushing was used vice a cartridge bearing that had a press fit to swingarm and really tight tolerances with respect to the through-bolt, would you still see the same flexing at the pivot?

    I can say without doubt that my bike does not flex like this even when placing direct, deliberate, lateral forces to the swingarm as I tried it after reading this very thread earlier last week.

    It'll be interesting to see how this develops...

    R/
    K

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    Good to finally see in action what I always felt Peter. But damn, you can imagine that kind of movement isn't very healthy for the shock, with it bolted directly to the swingarm and actually acting as a brace.

    EDIT: Right, I'll end my flex crusade here.
    Last edited by Boozzz; 01-14-2008 at 02:43 AM.

  53. #53
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    Quote Originally Posted by Konish
    I can say without doubt that my bike does not flex like this even when placing direct, deliberate, lateral forces to the swingarm as I tried it after reading this very thread earlier last week.
    Try harder: wheel between your legs, place some massive side force on the saddle, or have someone else try and push the front of the bike to the side and you've got your movement. Because the leverage ratio from the wheel hub to the pivot point is so large, and because the two halves are completely separate except for at the wheel and pivot, there's lots of room for flexing. It's inherent to the design of this type of swingarm, and it most definitely flexes on each and every Prophet. Wether you notice it, that's a different story. Some people do, some don't. If you don't, just go out and ride and don't worry too much (but keep an eye out for worn out shock bushings).

  54. #54
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    Quote Originally Posted by ar1981
    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
    Yeah, tell me! The whole bike flexes against the seat and top tube. Since only few complained about the flex in years may be there is something wrong with my specific frame?

    Unfortunately I can't compare it to anything else. I don't remember seeing that with Kona Kikapu but it is possible that I did not pay any attention to it. The other FS frame I had was so bad that was even pulling bearing from the linkage as it was flexing, this was a design issue so again, I can't compare it with.

    May be I need to knock some biker down and steal his or her bike for testing?

    One more things, I do not put much force in the beginning of the second video, I am starting propping the bike down the hill and yet it flexes.

  55. #55
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    Quote Originally Posted by yogiprophet
    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.
    Yes, I too think that laterally it is pretty strong. In the video you do not see that the BB would rock left to right it only twists.

    Quote Originally Posted by yogiprophet
    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.
    Yes, going to a different design can still have the same flex but less noticeable. However BB flex should be noticeable regardless the frame design. Here BB flexes nicely.

  56. #56
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    Quote Originally Posted by ozvena
    Yeah, tell me! The whole bike flexes against the seat and top tube. Since only few complained about the flex in years may be there is something wrong with my specific frame?
    I don't think so. Mine flexes about the same amount. It will depend, of course, on how much you weigh and how much force you apply to the pedals. I am about 180 lbs. how about you?

    If I have the right tires and tire pressure, my Prophet rails very nicely. If the frame did not give at all, first of all it would be to damn heavy to climb with and secondly it would probably throw you around on the trail too much with every off angle obstacle.

  57. #57
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    Quote Originally Posted by Boozzz
    But damn, you can imagine that kind of movement isn't very healthy for the shock, with it bolted directly to the swingarm and actually acting as a brace.

    I never had a problem with my shock. The rear DU bushing needs to be changed every couple of months and the front one I change half as often.

    I have a DT Swiss platform shock on the way to give it a whirl. It has eyelets instead of bushings so that no side loads can be placed on it, and the platform is adjustable. Looking forward to the very cush setting

  58. #58
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    Yogiprophet, I am 195lb on XL frame.

  59. #59
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    Quote Originally Posted by ozvena
    Yogiprophet, I am 195lb on XL frame.
    OOOHHH I was think you would be about that. A man of your stature would flex any frame. You may not notice it because of what I mentioned earlier. If you had a 4bar it would flex more laterally which is much harder to pick up visually.

    BTW, I've got a blue XL too. Is yours a 2005 Prophet 600?

  60. #60
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    Quote Originally Posted by yogiprophet
    Is yours a 2005 Prophet 600?
    No, I have a black 07 frame 6.

    Quote Originally Posted by yogiprophet
    A man of your stature would flex any frame.
    While weight has certainly an increasing effect (takes harder to pedal to move the "heavy" body along), you can see the frame flexing pedaling down the hill (first few secs of the 2nd vid) where the effect of the wight is somewhat diminished by gravity. I could also do a test on the straight flat surface with no acceleration where weight has no ill effect. It would still show some flex. Try it an let me know.

    Friend of mine has Specialized FSRxc and he is even heavier. His vid (a different camera angle) shows the rear hub moving sideways in a similar tests.

    All this shows that it makes no sense spending hundreds on 10mm axle wheel upgrade and it will hopefully serve the purpose (educate).

    Do I feel the twist? Well... no, but I do not have a reference point. About a month before I got Prophet and was with no bike to ride and I demoed HiFi Pro Carbon. This super light thing felt so good like nothing else before. I was smashing down though rocky gardens like never before or after. Very stable bike it seemed that time. Was that the 'cool' effect? Possibly....I had my proud moments with a new Prophet too but never felt the same as on HiFi. Who knows why, there are many variables...
    Last edited by ozvena; 01-14-2008 at 05:17 PM.

  61. #61
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    Quote Originally Posted by yogiprophet
    I never had a problem with my shock. The rear DU bushing needs to be changed every couple of months and the front one I change half as often.

    I have a DT Swiss platform shock on the way to give it a whirl. It has eyelets instead of bushings so that no side loads can be placed on it, and the platform is adjustable. Looking forward to the very cush setting
    That's quite often I'd say. Yes, DT's spherical bushings should help prolong both shock and bushing life.

  62. #62
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    Well I went out and put the wheel between my legs and the applied a lateral force on the seat post at its highest setting for increased leverage. I did see a *tiny* bit of flex, but it was very near the point where the rim itself was touching the swingarm. Additionally, I went for a ride on a 2 adjacent soccer fields so I could look a the post/swingarm area while I rode and did similar experiments as the video portrays. If there was flexing, it was imperceptible to me as I rode (both felt and seen).

    So I agree that the Prophet has *some* flex at the pivot, but *my* Prophet had nowhere near the amount of slop as in the video. Could it simply be loose or broken hardware in the pivot itself? The manual does state to look for excessive play...i.e., it didn't say "zero" play. If excessive play is found, then it's time to check and/or replace components.

    I'm guessing that not much in terms of wheelset, hub or axle will make a huge difference in removing the lateral flexing at the pivot point itself, but *may* help in reducing any twisting in the swingarm that may or may not contribute to the movement presented in the video. I also think that if parts obtained were on the tighter end of the tolerance spectrum in the swingarm assembly, a really sloppy swingarm could be tamed quite a bit.

    R/
    K

  63. #63
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    My 2007 carbon Rush flexes about the same as my 2005 Prophet. Both swingarm bearings and pivot "bolts" are in great shape and are the original ones.
    The flex is definitely rider mass dependent.

    Again, what you are seeing in the video is NOT swingarm flex. It is mainly the main frame twisting under the torque of pedaling. The more you weigh, generally the more torque applied.

  64. #64
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    I saw the video, and while I didn't like seeing all that flex, it seems to me that some flex might be an ok thing. If it was totally stiff, it seems like the bike would just skip off of every bump in the corners and provide very lttle traction. The bottom line for me is, does this flex really negate the way the Prophet handles on the trail? I know it's a personal preference, but I'm considering a Prophet and I'd like to hear some more feedback. I can probably deal with the flex unless it's just horrible, as Boozz said

  65. #65
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    Swingarm flex or frame twist...whatever you want to call it, it's movement at the pivot point. I weigh 225 and barely noticed it. I agree to call it swingarm flex is a bit misleading as it's a pretty burly beast.

    I still think parts (bearings, pivot pin, spacers) that are on the tighter side of the tolerance will tighten things up more than say parts that are on the looser end of the spectrum.

    Again, I weigh more than the video poster and for sure my frame/pivot area does not display anywhere near that kind of movement. Maybe with a few more miles as parts begin to loosen up, I'll start seeing more movement.

    R/
    K

  66. #66
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    I don't believe this flex induced by pedaling has anything to do with a body weight. A trained 160lb guy can push harder than an untrained 200lb one.

    On a bike which flexes when pedaling so much this thing must flex on rocky gardens going DH whether you pedal or not (I don't have a cam which would survive such test). Here the speed and body weight would be a factor. Flex is never good! That is why you have 36mm forks and stiff lefty.

    On the other hand you do not want no flex as the material would break. Such bike with no flex doesn't exist. It would weight 100lb.

    I spent an hour searching on SC forum and was looking for the same issue on Heckler. Some did report some flex, folks over 200lb and some really heavy folks too. However no one would describe it as such as a big issue as here.

    The pedaling induced flex comes to play in efficiency when your energy is waisted flexing the frame tubing. On DH a flexible frame may cause instability.

    I am seriously considering Heckler as replacement. On the other hand I am not a pro and do not need win races...

  67. #67
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    Okay....I've done some testing here too....
    I can get my swingarm to flex like that too, but only if I:

    a). Adjust the shock with too much pressure where the suspension doesn't move period and doesn't have any sag (just like in the video BTW)

    b). Pedal hard with my RIGHT leg wile being on the granny gear in front and 32 in the back while applying forces on the opposite side with my rear brake dragging.

    Bottom line: If you want to make the swingarm flex like in the video just to proof a point you're not riding normal but only in a way to MAKE the swingarm flex.
    If you use the above mentioned method you can get even get a Hardtail to flex!

    TRY IT OUT FOLKS! AND PUT AN END TO THIS DISCUSSION THAT MAKES THE PROPHET SOUND LIKE IT'S MADE OUT OF JELLO!
    "Common sense isn't always that common!"
    Custom Prophet and Custom Delta V

  68. #68
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    or:

    c) Use shock lockout instead of a high pressure. And pedal normally or hard if you want to call it such on any gear combination (see the gear combination on the video). Is this not "riding normally"?
    d) Use normal pressure and pedal normally or hard if you want to call it such (not on the video.). Is this not "riding normally"?

    Propedal schock should not let you bounce too much anyway which is equal to lockout or a high pressure. Also low or normal shock pressure can't keep the frame/swingarm/pivot from twisting.

    Are you suggesting that there is something wrong with my frame? I am eager to get to the bottom of it and hate to spent $$$$ on a new frame which would behave the same.

  69. #69
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    Quote Originally Posted by go-pirates
    I saw the video, and while I didn't like seeing all that flex, it seems to me that some flex might be an ok thing. If it was totally stiff, it seems like the bike would just skip off of every bump in the corners and provide very lttle traction. The bottom line for me is, does this flex really negate the way the Prophet handles on the trail? I know it's a personal preference, but I'm considering a Prophet and I'd like to hear some more feedback. I can probably deal with the flex unless it's just horrible, as Boozz said
    If there were no flex between the wheel and the seat, then every little off camber trail variation would be felt at the saddle.

    On the other hand, as ozvena pointed out below, frame flex takes away from efficiency. But I won a race and had 2 second place finishes out of 4 expert level races on the Prophet. The Prophet is not a pig, so it's gonna flex a little. But it is a fast bike - no kidding.

  70. #70
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    Most pro reviews of the Rush's similar swingarm say its laterally stiff.
    However, for '08 a bridge was added to the Rush swingarm.

    In one of these flexy Prophet threads, a few posters mention receiving replacement Prophet swingarms due to a bad batch. That may have been in an unrelated (?) swingarm clicking sound.

    High bushing wear would be indicative, and no shop people Ive spoken to are aware of it.

    2008 is the last year for the Prophet. It seems like a short production?


  71. #71
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    I had a clicking noise from my swing arm which was only on a certain batch of swing arms as per this link:-

    http://www.cannondale.com/asset/iu_f...echnote_en.pdf

    This was possibly only a Europe thing? and thats why non of your shop people had heard of it! However it does not in anyway relate to the alleged "superflex" of the swing arm, it was merely an early construction F/up inside the 'Hotbox'

  72. #72
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    Ozvena,
    I personally don't think there is anything wrong with your frame per se, but I do believe if you really want to get to the bottom of it, you need to eliminate some variables.

    If it were me, I would not involve myself in guessing about what could be wrong....if anything. Even though the parts visually look okay, I would for sure get a micrometer out and measure the diameter and bores of all related components. I mean it does not take much to make machined parts go from a tight press fit to a really sloppy slip fit.

    I would then approach a Cannondale rep and ask what the acceptable tolerance range for each bore/diameter of the respective component(s). If they can't help with that, then you may have to do more research (i.e. contact a bearing manufacturer for their tolerances on the same size/type bearing, or they may have it on their website etc).

    If nothing else, lets say the pivot pin bore in your frame is significantly out of tolerance in comparison to the pivot pin fit, you may be able to get them to warranty your frame. Certainly I would think that would hold true for the swingarm as well.

    I have in certain circumstances contacted custom machine shops to make pieces out of different material or sizes for other applications in the past (mostly car parts). It's expensive though.

    While I'm *not* saying there is an inherent design flaw with the Prophet, I do believe that like any mass produced component (i.e. bearings, pins, spacers), there can be a range of what's acceptable from the manufacturer. Now, if you just happen to get a combo of parts that are all on the "sloppy" side, it will for sure make a difference in the way things are supposed to fit together.

    If you've ever built a car motor, you know what I mean. Consider shell bearings. Even the sizes on the box from the manufacturer can be out enough to make other clearances too tight or too loose which is why I check the fit in a mock-up install (or by measuring) to be 100% sure.

    Anyway, I have to say I think the movement in your pivot area is excessive in comparison to mine which *barely* moves under the same conditions. Did you consider sending the vid to Cannondale to see what they say?

    R/
    K

  73. #73
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    Konish,

    There is no play, that is what you are referring to when you suggest to use a micrometer.

    What is happening is that the frame twists under the pedaling forces. You can see that the big crank ring twists, that means that BB twists, that means that the pipes welded to BB shell twist and as well do the holes where pivots are mounted in relations to the top tube/shock.

    Every frame twists but with single pivot where swing arms are so close to the seat tube it may be especially noticeable. I did not realize that the whole frame flexes until I took the vid. I thought that only the real swing arm flexes. The rear swing arm may be the stiffest part of the frame. I have stiffened it by using 10mm axle but it did not do the trick which confirms??? that it is already stiff enough.

    Also this is a XL frame, the leverage of a long seat tube + seat post is high and bigger frame is easier to twist as well. This may explain why some do not experience the issue. So it is not my 195lb! It is my 6 foot 3.

    The seat tube must twist too but on vid it doesn't. The reasons is that the top is beefed up by a 410mm seat post inserted pretty deep in the frame. So it got to flex closer to the BB weld. This is something I did not have an explanation for until now. Now it all comes together.

    The bike was visually inspected by a dealer and no issues where found. The dealer saw the vids and was very surprised. He too suggested that that there is possibly some play, loose bearing or something. I don't think so.

    I have rode Rush from the dealer on the parking lot and it appeared to flex the same way.

    It would be interesting to see a similar test performed with comparable frames like 575, Heckler...we just do not know what to expect not seeing a comparable test.

    One thing I noticed even before I got Prophet was that Heckler uses a larger diameter seat tube which can translate to a heavier and stiffer frame. This was my concern back then but figured it can't be an issues given the good reviews but I think a larger diameter seat tube make sense here.

    If I learn more I will post here.
    Last edited by ozvena; 01-19-2008 at 11:31 PM.

  74. #74
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    Do you guys know if the 08 Prophet has the same re-enforcement bracket welded in the bb area like the 08 Rush?
    It seems like they beefed up the pivot area quite a bit by welding a plate on the downtube between the pivot and bb.
    Makes me wonder...
    "Common sense isn't always that common!"
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  75. #75
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    There are some contour lines around BB area of Rush:
    <img alt="http://video.cannondale.com/images/08/bikes/CUSA/large/8VM4_wht.jpg" src="http://video.cannondale.com/images/08/bikes/CUSA/large/8VM4_wht.jpg">

    I am assuming that this is what you mean. I can't find 08 Prophet frame pic.

    Here is 07 Prophet frame:

    <img alt="http://www.cannondale.com/bikes/07/CUSA/large/7VE2_slv.jpg" src="http://www.cannondale.com/bikes/07/CUSA/large/7VE2_slv.jpg">

  76. #76
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    I made few changes in the shock pressure and rebound setting and that appears to made my prophet riding better through rocky gardens as before. I really enjoyed the ride today.

    I just checked the rear tire the air pressure, 30 PSI which is 5 to 10 PSI less than I ride. That probably provided more sharp edge damping.
    Last edited by ozvena; 01-21-2008 at 08:30 PM.

  77. #77
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    Quote Originally Posted by ozvena
    Konish,

    There is no play, that is what you are referring to when you suggest to use a micrometer.

    What is happening is that the frame twists under the pedaling forces. You can see that the big crank ring twists, that means that BB twists, that means that the pipes welded to BB shell twist and as well do the holes where pivots are mounted in relations to the top tube/shock.

    Every frame twists but with single pivot where swing arms are so close to the seat tube it may be especially noticeable. I did not realize that the whole frame flexes until I took the vid. I thought that only the real swing arm flexes. The rear swing arm may be the stiffest part of the frame. I have stiffened it by using 10mm axle but it did not do the trick which confirms??? that it is already stiff enough.

    Also this is a XL frame, the leverage of a long seat tube + seat post is high and bigger frame is easier to twist as well. This may explain why some do not experience the issue. So it is not my 195lb! It is my 6 foot 3.

    The seat tube must twist too but on vid it doesn't. The reasons is that the top is beefed up by a 410mm seat post inserted pretty deep in the frame. So it got to flex closer to the BB weld. This is something I did not have an explanation for until now. Now it all comes together.

    The bike was visually inspected by a dealer and no issues where found. The dealer saw the vids and was very surprised. He too suggested that that there is possibly some play, loose bearing or something. I don't think so.
    Ozvena,
    No offense, but I don't believe that the frame (tubes, bb shell or pivot tube bungs) is twisting as shown in the video. If indeed the welded tubes (and components) themselves were twisting that much it would certainly lead to material failure in short order. I do acknowledge that frames will twist under load, but certainly nothing like we see in the video, nor do I think that pedaling the bike would generate enough torque to twist the welded tube at the bottom bracket.

    I watched your vid(s) many, many times on replay and the big ring's position to the bottom tube does not change as far as I can tell. While it may look as though the big ring is twisting in your "tough hill" video, it looks more like the result of the camera being solidly mounted while your pedaling is inducing a rocking movement.

    All the movement in either video is limited to the swingarm and shock. I firmly believe that all of the source of flex in this bike is the pivot point itself. The "flex" can be induced by placing the rear wheel between your legs and torquing the seat tube laterally. The only force being applied to the main triangle is from the seat tube while the head tube is free to move in the same direction! Twisting of the main frame would have to come from deflection of the seat tube and head tube in opposite directions.

    I really hope you get to the bottom of this...good luck

    R/
    Konish

  78. #78
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    i rarely ever notice any flex in my prophet and when i do it's because i landed sketchey or i'm really hammering away. i only weigh 165 lbs,a big man will notice more than i do. if i had to do it all over again i'd still pick a prophet over all the bikes i've ridden. it rocks that much!!

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    oh jes, those flexy prophets! it was written in so many tests, it must be true.
    SO HERE IS THE FACTS:
    I measured the folowing frames for rear arm side flex as well as the following wheelsets and tires under a force of 400N from the side:
    Prophet: 3mm
    Rush Alu: 3mm
    Perp: 2mm
    Ironhorse 7: 2mm
    stock Rush 600 rear wheel (Mavic XM 117): 17mm
    Mavic EX 729 on Hope Pro 2, DT comp: 2mm
    Maxxis Larsen TT 2.0 on EX 729: 11mm
    Schwalbe Nobby Nic 2.25 on Mavic 112: 15mm
    Michelin C24.1 on EX 229: 6mm

    all tires were tested at 45psi.
    So who will tell me he gets the difference from 1mm flex between a hardcore Freerider
    and a Prophet or Rush when the rest of the back components are flexing between 8mm and 32mm? on stiff downhill rear components its about 10% more flex between Freeride and CC. on light cc rear components its about 3% difference (Perp to Prophet). so who of the flexers can feel these 3 %? so it seems that rear stiffness is more about wheels and tires than anything else.
    just my 2ct.
    CW

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    What did you measure? How did you measure it? How big the frame was? You measured the swingarm flex but I thing the problem is somewhere else.

    I am not saying that I can feel it but I would rather the energy being directed to the chain instead of flexing the frame ( but I am not sure if such ideal bike exists (frame under 6.5 lb) with no such flex under pedaling).

  81. #81
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    Prophet was L and S
    Rush was S
    rest were M
    frame were mounted on a large "Kreuztisch" preloaded by 30N in the rear axle direction
    to eliminate bearing play and measured for deformation in axle direction on the axle. all frames were measured with a rear hub mounted.
    every frame flexes it is impossible to desing a frame that wont flex. in my opinion the energy wasted must be similar to zero (the chainforce cant get weakened and the mechanical work done by flexing the stays should be very low). otherwise the swingarm would heat up by the mechanical work transfered to heat.
    CW

  82. #82
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    I can't still see what you did and I am not familiar with "Kreuztisch", may be someone else is. May be a picture of the test setup would explain it. Can you post it?

    I think the swing arm is fine as I did not see any evidence that there is a flex on the swing arm itself. You have tested the swing arm so may be your test is not valid for this discussion?

    What makes you believe that the element which flexes, again I don't believe it is the swing arm, doesn't heat up?

    I appreciate for going through so much trouble!

  83. #83
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    Weird. I have been running Prophets since they came out, I have had six because i work at a shop and change up every year for a new one plus I build up MX's for slalom and dirt jumping. I ride really technical stuff-Auburn, Downieville, Rubicon etc. and I weigh 190lbs. I have four friends that are all the same size or larger on the same bike and none of us have had any of these issues. I ride extremely technical descents and climbs, stuff most others cannot climb on my Prophet. I have had the regular trail version and the mx and they are by far stiffer than a Jekyll and in my opinion one of the stiffest bikes I have ridden. I have spent lots of time on Nomads, Hecklers, Bullits, Intense, Specialized, Trek, Fisher, Turner, you name it. I see the commonality in changing out flexy wheels solving the problem, maybe that is the issue?

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    exactly what my test pointed out, Heath Sherratt. most rear end flex comes from tires and wheels, not the frame itself. i think the tests were quite correct. my gf is driving two Rushes (1. CC setup Crossmax SL disc, 2. Mavic EX 729). the crossmax one is flexing as hell (under my190lbs) but the other one is nearly as stiff as my freerider (nearly!). without testing its very difficult to say what part of the bike is flexing. many people are just repeating what they have heared or readen. all i wanted to say: this bike has no rear end that can be felt flexy. by the way a german freeride bike (Fusion Whipplash) which is always called very stiff, has more flex than a Rush. so if you have a flexy rear end just buy a good and stiff rear wheel and your problem is gone.
    CW

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    Yeah, I have seen this so often in bikes that I will always, without question or exception, take my wheels and re-tension/true them if I didn't build them myself. Interesting that this is a common enough occurrence, yet folks just don't pick up on it. Inform the people! Thanks for all the testing and info you're doing. It's nice to see facts and not e-spec. Prophets been a great bike, i can't wait to see the Rize and the Moto.

  86. #86
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    Quote Originally Posted by cwrender
    Prophet was L and S
    Rush was S
    rest were M
    frame were mounted on a large "Kreuztisch" preloaded by 30N in the rear axle direction
    to eliminate bearing play and measured for deformation in axle direction on the axle. all frames were measured with a rear hub mounted.
    every frame flexes it is impossible to desing a frame that wont flex. in my opinion the energy wasted must be similar to zero (the chainforce cant get weakened and the mechanical work done by flexing the stays should be very low). otherwise the swingarm would heat up by the mechanical work transfered to heat.
    CW
    Was zum Henker ist ein Keuztisch? Kannste' vielleicht mal ein Bild posten?
    "Common sense isn't always that common!"
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    Can you still get the MX version with bolt thru rear? Or alternatively use DT240 hubs with the RWS system?

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    You might be able to order a swingarm thru your LBS...
    I'm pretty sure that c'dale ditched the MX version for 2008.....
    "Common sense isn't always that common!"
    Custom Prophet and Custom Delta V

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    kreuztisch ist ein in 2 achsen verfahrbarer tisch für eine fräse odgl. hat nuten für spannblöcke un muss absolut eben und steiff sein:
    http://de.wikipedia.org/wiki/Kreuztisch
    in meinem fall nur 200cm*200cm gross. und nein, ich habe keine photos gemacht (war ja auch nichts spektakuläres zu knipsen).

  90. #90
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    Quote Originally Posted by wellmt
    Can you still get the MX version with bolt thru rear? Or alternatively use DT240 hubs with the RWS system?
    What for?

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    Quote Originally Posted by cwrender
    kreuztisch ist ein in 2 achsen verfahrbarer tisch für eine fräse odgl. hat nuten für spannblöcke un muss absolut eben und steiff sein:
    http://de.wikipedia.org/wiki/Kreuztisch
    in meinem fall nur 200cm*200cm gross. und nein, ich habe keine photos gemacht (war ja auch nichts spektakuläres zu knipsen).
    Ach so... ich dachte daß das so Tisch ist, wie man beim Rahmenbau verwendet... wäre aber interesant gewesen zu sehen, wie die Rahmen darauf befestigt werden...
    "Common sense isn't always that common!"
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    Quote Originally Posted by ozvena
    What did you measure? How did you measure it? How big the frame was? You measured the swingarm flex but I thing the problem is somewhere else.

    I am not saying that I can feel it but I would rather the energy being directed to the chain instead of flexing the frame ( but I am not sure if such ideal bike exists (frame under 6.5 lb) with no such flex under pedaling).
    Wait a minute... are you saying that you CAN'T FEEL the "flexing" frame???? Don't get me wrong.. I certainly don't feel any obvious flex in my Prophet and if it's there it doesn't affect my riding. So basically all this whoo-ha about "flexing" Prophet frames is just because of the video and not actual feel?
    Last edited by vitaccop; 01-23-2008 at 07:27 PM.

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    Say again?

    Going back a few years when C-dale used Weinmann rims, but those stock wheels were flexy, so maybe its just another case of a weak low level wheel.

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    Provide me with a reference point and I can say how it feels or speak to the folks who has it and can tell you how it feels or just read all the pages again.

    Look at vids again and you see no wheel. You are mistaken it for the seat tube. So I am not sure where this wheel theory is coming from. At least it is not my case. I can see that some upgraded from lighter wheels to some heavier with 10mm axle and felt an improvement.

    And no, I do not see or feel my wheel flexing but I see flexing of the frame when pedaling even with a slight effort. When I put some punches clipped in the images are quite surprising when I look down...is this normal? Hell how do I know, don't have a reference point.

    No need to highlight stuff in RED I can still see fine and know precisely what I wrote.

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    Quote Originally Posted by ozvena
    What for?
    Do you mean the RWS system?

    With the correct adapters it's a way of converting a QR wheel to a "bolt thru" style axle but which will fit in standard QR dropouts. The axle thickness (9mm Front or 10mm rear) combined with the extra clamping of the Ratchet system is supposed to increase stiffness. Therefore this should help prevent the rear twisting.

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    wellmt,

    If the goal is to deal with what I experience then let me repeat that what I experience is with 10mm rear Saint axle. It doesn't use "flimsy" RWS (in comparison with Saint). The torque for that 10mm axle is 45N/m or 392in/lb. This is more than you can do by bare hand and RWS would be twisted off with such torque:

    http://techdocs.shimano.com/media/te...9830606654.pdf

    If you are getting for a cool effect go for it...if you are getting a better rim with it, go for it...if you are expecting that the frame would be stiffen, you may be disappointed as I was. I my case it wasn't worth the extra expense, effort and may be even some extra weight penalty.

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    The original poster mentioned nothing about bolt thru axles. I was merely offering a suggested alternative to a bike fitted with standard QRs which may help (from your experience it seems that in fact it may not). The weight difference between RWS "bolt thru" and standard 5mm RWS QR is something like 8 grams.

    I don't have a flexing problem though.

  98. #98
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    great!
    What do I know, ask the "experts"!

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    The prophet rear swing arm problem was identified by myself and a local bike shop to be the QR skewer. The force needed to hold the rear wheel strait in high and overloads the Shimano QR. I went to a DT Swiss Or Mavic and cured the problem out right. This was about 98% of the bikes we saw with the Cannondale rear swing arm. The Larger the contact area for the QR the better and the use of higher pressures is also needed

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