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dekindy
03-08-2008, 02:20 PM
My new Legend has a 74.5 degree seat tube angle versus a 73 degree angle on my old Fierte. Assuming they transferred all my measurements over to the new Legend exactly, what would that mean if anything regarding stresses on my legs?

The reason that I am asking is that I am getting some tightness right behind my knees and my hamstrings are getting worked more. Less stress on my quadriceps to spread the work among more muscles and should make me a stronger rider. Lactic acid would build up less also since it would be concentrated in less muscles and have more ways to be removed. Would anyone else agree with any of this?

Or did my position just not get transferred exactly and I need to do some adjusting to get back to where I was? I was very comfortable before.

Or do I just need to work on a smoother pedal stroke?

Louis
03-08-2008, 02:25 PM
Your saddle should in in the same position relative to the BB regardless of the STA, so if the fit is transfered properly STA will have no effect other than whether or not you need a a seatpost with setback and the saddle fore-aft position in the clamps.

dekindy
03-08-2008, 02:33 PM
Your saddle should in in the same position relative to the BB regardless of the STA, so if the fit is transfered properly STA will have no effect other than whether or not you need a a seatpost with setback and the saddle fore-aft position in the clamps.

That is what I thought. My fitter had Serotta put my dimensions in their software to confirm the frame would fit and I would have enough setback.

So is the primary effect of the steeper STA, everything else being equal, it that it allows for shorter chain stays so the frame will have better climbing characteristics? When we held the Legend frame up to the Fierte they were almost identical except for the STA.

Any difference in front to back weight distribution?

Louis
03-08-2008, 02:51 PM
I'll let the folks who actually know what they are talking about handle those other questions...

If you like you can investigate and compare weight distribution by putting a few books under one wheel and a bathroom scale under the other, then swapping things (and if you are anal about it, double check by standing on the scale while holding the bike to see if it all adds up). Dave Kirk posted a question about weight distribution a while back. You might want to search for that for some reference info on what other folks have.

Smiley
03-08-2008, 03:39 PM
My new Legend has a 74.5 degree seat tube angle versus a 73 degree angle on my old Fierte. Assuming they transferred all my measurements over to the new Legend exactly, what would that mean if anything regarding stresses on my legs?

The reason that I am asking is that I am getting some tightness right behind my knees and my hamstrings are getting worked more. Less stress on my quadriceps to spread the work among more muscles and should make me a stronger rider. Lactic acid would build up less also since it would be concentrated in less muscles and have more ways to be removed. Would anyone else agree with any of this?

Or did my position just not get transferred exactly and I need to do some adjusting to get back to where I was? I was very comfortable before.

Or do I just need to work on a smoother pedal stroke?
Let me put it this way. Your new Legend is about 1.5 cm forward with the saddle, IF you were using with your Fierte with a non off set seat post and your saddle was dead center on the rails and your Legend has an off set post and the saddle is way back your KOPS is not in the same spot, Now ofcourse this 1.5 cm I told you about is for an average 56-58 cm frame and gets longer or shorter based on the length of the seat tube and post extension. I don't even want to guess as to how the TT lengths compare. I will be more then happy to discuss this off line and not here.

But if you want to see for your selfjust set up your Fierte with the same saddle and drop a plumb from the nose of the saddle and see where this plumb is relative your BB and do the same with your Legend and if they are not the same off set distance they are not set up identically which explains why the pain. Set them up identically and you'll be OK on the KOPs and maybe not the reach.