Bike fit leads to confusion.......HELP !!

[Schluff]

I went to the bike fit this morning before work, fitter told me that I have above average torso length dimensions and shorter than average legs for my 5 ft 9 inches height. He calculated that the optimal frame size for me was 522mm and top tube length 543mm.

He made adjustments to my 56cm trek 1000 to ascertain the 655mm reach that he said I should have and I absolutely hate it, he said there is no doubt the 56cm is too big for me. He said the 175mm cranks were totally unsuitable too and i should be riding 170mm types as my inside leg is 29 inches.

Im caught between a new frame of size 53cm and 54cm.

If I select the 53cm frame, , the frame height from bottom bracket to seat tube will be 530mm or 8mm above the recommendation and the top tube will be 529mm, or 14mm below recommendation.

if I select 54cm frame, the frame height will be 540mm or 18mm above recommendation and the top tube will be 543mm which is exactly what was recommended.

I could sort out the top tube length issue with the 53cm frame with a longer stem, but am not sure if I should just buy the 54cm type

I cant afford a custom frame...............damn my short legs

If you were me, is the 53cm with longer stem a wiser choice than the 54cm or vice versa,please look at the dimensions I gave.

 

[oldbobcat]

Yeah, I'd go with the smaller size and a longer stem. You might also search out frames that are somewhat longer in the top tube. Two that come to mind are Specialized (all men's road models) and the Felt F-series.

Also be wary of fitters who simply go by the numbers. Fitters need to listen to the client and observe the body's balance over the bike.

 

[swampy1970]

Schluff, What do you hate about your new position on the bike?

I'm going to take a guess based on past bike fits here in the US and say that you feel too cramped and it feels like your bars are way too close.


If it's so bad that you cannot stand riding it then tell the fitter that they need to fix it. If it means going back to your old position then so be it. Different doesn't always mean better. The fitter may think they're right but you're the client and if you can't stand it and it makes riding a chore then the fitter is wrong.

As oldbobcat said, be wary of fitter who use calculations for their final fit. That involves the very dangerous assumption that you're flexable, functionally sound and have no extreme asymetry issues or other "issues" but reality is far different.

A good bike fit will leave you sitting on the bike comfortably with a functionally stable position that doesn't illicit pain during the course of a ride. A simple goal that usually requires lots of little challenges to be overcome.

If you address the usual suspects of saddle height and setback as well as cleat angle you'll be part the way there. Likely your legs will be different lengths - you'll need to address that. Also fairly probably you feet will want to sit at a different angle on the pedal. Shims and wedges will address those - it's not rocket science to do. You'll also need to ensure that the foot is happy inside your shoe so a correctly fitting shoe with the correct arch support (each foot will be different - fun aye?) is key. Once you have that little laundry list nailed down you can start to think about where the bars need to go...

Take a look at Steve Hogg's bike fitting website. There's a massive amount of good stuff on bike fit. Some of it, when you sit and think about it, is common sense once you remove the notion that "bikefit=formula" and "formula=the truth." Some of the stuff on Steve's website is still a little bit hard to comprehend the exact why's and wherefore's but being one to give something a whirl I gave them a try with sucess. I never thought that my sunglasses affected my bikefit.

After using alot of the information on Steve's website I feel that "formula= recipe for disaster" unless it's used only as a quick guide on where to start from.

 

[oldbobcat]

Originally Posted by Schluff .


I cant afford a custom frame...............damn my short legs

If you were me, is the 53cm with longer stem a wiser choice than the 54cm or vice versa,please look at the dimensions I gave.

I want to add that I favor the smaller frame because you or the fitter would be less likely to move the saddle forward to reduce reach to cranks, to accommodate your short legs. You will probably need considerable saddle setback to offset the mass of your long torso.

And cranks no longer than 170.

 

[kdelong]

I agree with the smaller frame recommendation. As for fit, the numbers are meant as a starting point and then the "right fit" is dialed in from there, even if the end result is way off from the original numbers. Anyone can come up with the numbers. There are a lot of formulas for them. The great fitter is the one who can take the numbers and combine them with feedback from the rider to assemble a bike that the rider is comfortable on.