Sportive vs racing geometry

jonomc4

So I have been riding a De Rosa R838 bike (self build) for about 8 months) I cycle up to 100 mile rides. All is fine and I find it very comfortable.

For Wet weather I have just finished building up a Roubaix spesh frame - and my god am I finding it hard to get the set up comfortable! I have played around with the stem length and angle and tilt of handlebars - but as of yet I have yet to get to the point where I can ride more than 6 miles without get pins and needles in my hands. The De Rosa has Zipp Service Course SL handlebars with thick gel inserts and Lizard skin bar tape - whilst the Roubaix has Fizik bar tape with their gel insert (not as thick in both cases) on Ritchey handlebars - could it be down to this?

What is really weird that despite the more relaxed Geometry I think I am getting a lot more weight going on my shoulders when I ride.

kamil1891

You could post the photos of both bikes and how they are set up. You could also measure bar-saddle drop, bar drops-saddle drop and saddle tip- centre of the stem to see actually how your bikes differ from each other in terms of fit. With these measurements I think we could help you more I doubt that is the bar tape that makes such a difference but it happens if you move from proper thick/gel bartape to something really thin and firm.

And for me something like "sportive geometry" is kind of a myth. You can make roubiax more aggressive than the allez (or the racey equivalent) just by adjusting number of spacers, stem degree etc.

jonomc4

thanks I will check that out - both bikes have only a thin spacer under the stem. I changed the angle from +7 degrees to flat on the Roubaix and that helped lessen the forward weight issues (I know that sounds counter intuitive but I learnt that when I took the first bike for a bike fit - it's all about centre of gravity apparently) but I still feel more weight on my shoulders!

I will check the drop - obviously saddle height is the same on both bikes and last time I checked the distance from saddle tip to stem end was the same.

meesterbond

I doubt the bar tape would have that much of an affect in just 6 miles. Have you taken measurements from the De Rosa (saddle height, distance from tip of saddle to BB perpendicular, tip of saddle to bars etc etc).
The fore/aft position of the saddle in particular makes a massive difference - if the saddle is too far forward then your centre of gravity is also too far forward meaning you put more pressure on the arms and hands. Moving it back may flatten the back slightly but also has the affect of evening out the pressure on butt and hands.

Saddle to stem tip is fine, but if your saddle isn't in the right place to begin with it's pointless...

I'd agree with the whole racing vs Sportif geometry... all it means to me is that I can run my R5 with the stem slammed 8)

jonomc4

I have based the fore / aft position of the saddle based on the below knee to centre of pedal crank - I always do this second after initial saddle height (which I then adjust through trial an error on the bike) as my knees are my most vulnerable part of my body to injury.

giropaul

No matter what the frame geometry is it's vital to have the same critical position measurements on every bike (I understand that Bordman kept an unridden "reference" bike just to make sure that he always went back to the same template). Teams have jigs, and keep riders' measurements to set their bikes to.

You've checked saddle height from bracket and setback (using an accurate method). I'm assuming the crank lengths are the same, and saddles are the same (and not sagging or worn).

Next is bar height relative to the saddle height. Check that the brake levers are in the same position on the bars as well. Then check reach - saddle tip to bars (but also, as you're using different bars, to the brake hoods and into the drops).

If everything is identical between bikes then there can't be any reason for them to feel any different, except in terms of maybe handing and ride firmness.

jonomc4

I think I cracked it last night.

The previous night I had moves the shifter up a bit. Yesterday I shortened the stem - the winter bike is slightly longer top tube. Saddle tip to stem is different on both bikes - but I have measured saddle for aft solely on knees over pedals position. The saddle height to bar height is different because the head tubes on both bikes are very different.

But at least I killed off the numbness as of yesterday (well at least on a 10 mile ride). Can't say I am enjoying the bike as much as the DeRosa which is fun to ride this is very dull I feel, but the bumps in the road are a lot smoother!