Road Cycling - Bike fit

Any one got any advice on getting my bike to fit me.


i have a ridgeback genesis day 02 - size large. (xl is too big ie cant sraddle the top tube). The problem basically is not having enough room to stretch out ie i keep wanting to hang my arse over the back of the saddle to achieve the most effcient riding position(which feels quite uncomfortable after only about an hour of riding anyway). The saddle has allready been positioned as far back as it will go. Also i seem to have quite a lot of wieght on my hands. (get numb after a while). I guess its a combination of getting a longer saddle or a longer stem and may be raising the head set (is this possible on an ahead set) any one know of a brand of saddle that has plenty of rail length for adjustabillity ?

Thanks

Roop.

Check that your cranks are about the right size for you.
Place your saddle to give knee-over-pedals (this is just a good starting point). If you want your saddle back further, then a seatpost with more layback may help.
You then need a stem to place the bars where you want them to be. An adjustable stem is a useful item here.

Try and get to a shop with a fitting bike, to play around with the variables.
BTW what is the top tube length and stem length of your bike?

Cheers for the info.

Ok, the top tube is approx. 570mm (i measured it from the centre of the seat tube hollow to the centre of the sterring post/head set) and the stem is 105mm(measired from centre of bars to centre of head set).

You mentioned the cranks - are you thinking they are too long or too short? will longer or shorter ones give me more stretch (ie stop me from wanting hang over the back of the saddle)?

I've moved the one remaining spacer ring/washer from below the stem to above the stem this has improved things quite a bit (i'm now sitting more upright and ther is less pressure on my hands!) is it ok to place a fourth spacer under the stem (i reckon there's just about enogh of the fork/steerer available for this) ive noticed i get a slight clicking from the head set when braking since moving the third spacer- any thought?

Thanks alot

Roop.

I would guess that a bike of your size would normally come with a 12cm stem.
My setup is a 54cm TT and an 8cm stem, but I chose that in place of the normal 10cm stem to get a shorter higher position.

I think your stem is too short, but without looking, I couldnt say for sure.
Cranks which are proportional to leg size will help any rider. You should probably be riding 175mm rather than 170mm cranks.

The starting place for any position is the pedals, so 175 cranks will place your foot 5mm forward at the 3:00 position, and 5mm lower at the 6:00 than if you used 170mm cranks
They will also encourage a spining circle which fits your legs.


Have a look at

http://www.peterwhitecycles.com/fitting.htm
and
http://simon.trinhall.cam.ac.uk/bike/cranks.html

You might look into the possibility of a bent seat post, which will help get your rump rearward. There are several good quality ones, but they aren't cheap.

Lengthening the stem would probably be cheaper. Also many threadless stems can be used either up or down to get your bar higher or lower.