# Flex in my '09 R3 when Climbing or Sprinting



## CycloneRunner (Apr 22, 2005)

For those who don't want to read the whole post here's a synopsis of my problem....

So one or two things are happening: 1. The frame is so stiff that it is magnifying the flex somehwere else in the bike. Only two places I can think of are my shoes or the wheels (Easton Circuits). 2. The frame has a build defect causing it to flex.

I'm going to try riding with a different set of shoes and my stiffer Mavic wheels tomorrow and see if I notice a difference. If it still seems like its the frameset I don't know how I can show or prove that to my LBS. Thoughts?

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Here's the rest of the story...

So I picked up a Cervelo R3 Force this spring and after spending a couple weeks trying to dial in my fit to match my old roadie (swapped out the Palladio straight post for a set-back K-Force post and I was good) I was set.

I'm enjoying the ride, lightness, handling, etc... of the bike but I am getting some _very _noticeable flex and power loss when climbing or sprinting out of the saddle. 

At first I thought it was strictly the Force crankset, which is known to be not as stiff as Shimano or FSA's cranks. In fact, I was rubbing my chain through half my rear cogs and you could see the chainring visibly move back and forth under load while pushing large gears. Both me and the LBS tried many times to 

So I replaced the Force crankset with an FSA K-Force Light and the chain rub is gone. 

However, getting out of the saddle or sprinting I am still feeling a lot of flex/power loss somewhere in this bike. As a whole it is not performing nearly as well under high power output as my old Specialized E5 which I have set up with Ultegra and Reynolds Solitudes. 

So one or two things are happening: 1. The frame is so stiff that it is magnifying the flex somehwere else in the bike. Only two places I can think of are my shoes (Nike Lance III, 2 years old) or the wheels (Easton Circuits). 2. The frame has a build defect causing it to flex.

I'm going to try riding with a different set of shoes and my stiffer Mavic wheels tomorrow and see if I notice a difference. If it still seems like its the frameset I don't know how I can show or prove that to my LBS. Thoughts?


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## Getoutandride (Sep 1, 2008)

check for cracks in the frame, especially around the BB junction, while your at it check the spoke tension on the easton wheel-set and check the rim over for cracks 

I am very doubtful of shoes, the wheelset isnt the greatest out there that would be the first place i would try rule out


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## shaochieh (Apr 19, 2002)

I have a RS and sometimes it does that. When I am using the granny gears going up a very steep hill then I get up a put some power on it then I feel the flex. The flex probably coming from your chainstay and seatstay. I have three carbon bikes and all three did the samething on the same hills. I am not really worry about it.


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## CycloneRunner (Apr 22, 2005)

So... I checked the frame for cracks, checked my wheels for spoke tension, tried different wheels, etc... and I still couldn't figure out why I was feeling this "flex" out of the saddle. Then, when I was changing my wheels this weekend in preparation for a race I noticed a waggle up by the rear dropouts. Sure enough, my derailleur hanger was loose would pivot a few millimeters if I spun the crank. It was not bent so I tightened that sucker up and viola - the "flex" I was feeling is gone. So the problem seemingly solved but for the record the stock derailleur hanger looks like a cheapo piece of stamped aluminum. After reading some forum posts around the web (search derailleur hanger R3 on google) I think I might pick up one of these.. http://wheelsmfg.com/content/view/663/27/


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## purplecu22 (Sep 25, 2005)

get the wheelsmfg. hanger. Improves your shifting a great deal. The stock hanger is crap. I did this and my shifting went from ok to sharp and crisp.


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## bandito (Apr 23, 2009)

*brand new r3sl*

derailleur hanger not only not remotely close to being aligned, but had a strip hex bolt. I replaced with a wheels manuf. one but had a hard time getting the one stripped bolt out. Keep in mind it was brand spanking new, so must have been stripped by some factory goon. Always check the alignment of these things on new frames.


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