Hi,
I have been googling tube ratios for my Cervelo P2 2012 which I am thinking of converting into a road race legal bike for draft legal ITU races but can’t seem to find the answer I need. Based on UCI and ITU regulations, I should be able to meet the saddle-chain wheel axle limitations by moving the saddle into the back seat clamp.
However, I am worried that the downtube/seat post does not meet the 3:1 UCI ratio. Can anyone help confirm this?
Thanks,
Wilson
the standard seat post definitely does not meet UCI rules.
You can get the conversion kit, but it is a bit of a hassle to live with. There is an insert/shim thing that the new seat post goes in to, and extra care has to be used to make sure nothing slips, and that you don’t drop the shim in the bike.
Thanks jackmott! 
Are you in the usa? If yes, you may want to check if uci compliance in the seatpost and frame even matters for the races you plan to enter.
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no, i race in Malaysia. Thanks for the advice but it is looking that I’ll have to buy a road bike. thought I could McGyver my way out of it!
TT frames have more allowance for “gusset” areas between the main tubes than road frames do.
There’s a guide to the frame envelope stuff at the link below, but it’s not always easy to measure things accurately, and potentially even different sizes of the same frame may change the strict legal status.
http://www.uci.ch/mm/Document/News/Rulesandregulation/16/51/61/Clarificationguideofrules2012-ENG_English.PDF
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