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Discussion Starter · #1 ·
I just picked up my new Cervelo RS (56 cm) this weekend and on my first ride, I noticed that my knees slightly hit my handlebars on climbs - I assume this isn't common. My old bike was 1996 Lemond Zurich (57cm) which has a different geometry (longer top tube). I did have a bike fit and I am sure my lbs will be able to help, but looking for some additional ideas.

If I increase stem length, wont this change my back angle and stretch me out more? Are there other options?

Thanks,
Mike
 

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You might want a longer stem. That will stretch you out more on the bike.

Or you may be leaning too far forward when you stand on climbs. If you don't want a longer stem, try conciously moving back a bit when you stand.
 

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info...

No mention of stem length?

FWIW, if I use a 100mm stem instead of a 110mm, my knees may occasionally graze the bars.

If you increase the stem length, of course it will stretch you out more. It won't change your back angle much. That's better done with more drop.

Since I have a very short torso, I use short reach bars (Easton EC90 SLX3). This allows me to use a 110mm stem with saddle set relatively far back for climbing.

One thing that many people don't know is that Shimano brake hoods have the longest reach of any brand and the new 7900 are even longer. IMO, that's a step in the wrong direction, since in requires a shorter stem to get decent reach to the hoods. Another reason I ride Campy.
 

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I had the same thing until I put the 120 stem that came with the bike back on. Feels a whole lot better better. I like standing especially going up hill. Feels so much better and natural without having to consciously remember to not lean in so much so I'm not hitting the bars with my knees.

I think a lot of us for some reason think our cockpits are to long so we shorten up our stems. I'm much more comfortable with the longer stem/cockpit now.

I'm not saying this would be true for everybody but I was told I have the short torso thing going on too. If your top tube's to long it's to long, but if your knees are hitting the bars, well, I'd say your top tube's not to long. Open up your cockpit with the longer stem.
 

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A 90mm stem on a 56cm bike seems a bit short if it came that way stock. Until I started having back problems (not bike related), I was using AT LEAST a 120mm on frames 56cm and larger. I'm using 100-110 now, depending on the TT, but 90 seems pretty short, especially if it has a lot of rise to it - you didn't mention what that was either.
 

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As C-40 mentions, getting some of your reach from your stem instead of your bars might be an option. But there may be a more foundational problem.

If you ride in the drops and bend your elbows to get properly low, how do your elbows and knees interact? If you are positioned well on the bike (that is, pivot forward from the hips rather than bending the spine) and fitted appropriately to it, there's seldom any reason for them to do any more than brush. That may not be a position you'd choose to use very often, but it's a decent indicator of fit nonetheless. (That does assume you are looking for aggressive positioning over a comfortable 'just riding around' sort of fit, of course.)

How much overall stack (vertical distance between cranks and bars) can matter, too, as it changes how you balance your weight between hands and cranks when standing. That's less about something that needs to be changed on the bike, than something that you may simply need a few rides to become accustomed to. If you are brushing your knees, there's a strong possibility that you have your weight too far forward, which can result in a lot of losses from front-wheel scrubbing on the pavement with each stroke. If you hear the shoosh-shoosh of the front wheel with each stroke, it's more about technique (as adapted to this particular bike) than necessarily about fit.
 

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Discussion Starter · #8 ·
My stem currently has a -6 degree rise. My Cranks are 175mm, if that matters. I also have SRAM Force (not Shimano). As a point of reference, I am 5'10" and have a 35" inseam with cleats on. I don't have any other measurements on hand.

Here are a few pictures, if it helps.

My normal riding position with hands on the hoods and seated feels ok, but I will experiment with your suggestions and see what it looks like and add more feedback.
 

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not -6...

Your stem is flipped up to +6, so the true horizontal length of that 90mm stem is only 83mm. No wonder your knees are hitting the bars.

The true horizontal length of a stem is often overlooked. People flip them to raise the bars and don't realize how much shorter it makes the stem.

I've got a similar spacer setup, but I use a 73 (-17) degree x 110mm stem that would drop the bars about 4cm lower.
 

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mjengstrom said:
I just picked up my new Cervelo RS (56 cm) this weekend and on my first ride, I noticed that my knees slightly hit my handlebars on climbs - I assume this isn't common. My old bike was 1996 Lemond Zurich (57cm) which has a different geometry (longer top tube). I did have a bike fit and I am sure my lbs will be able to help, but looking for some additional ideas.

If I increase stem length, wont this change my back angle and stretch me out more? Are there other options?

Thanks,
Mike
Try shorter knees....
 
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