Sunday, 21 December 2014

The Praying Mantis TT Position - Is it back?

UCI time trial regulations are one of the most dynamic in the rule book. It seems every six months the UCI publish changes, updates, or clarifications. Things are progressing and becoming easier for commissaires to review bikes and equipment before a race, if they choose to. It is also a mandatory requirement of competitors to be up to date with the rules.... a tough ask when things keep changing!

I've had a lot of riders ask about pushing the limits when it comes to TT bars/lever height to get themselves into a very aero-aggressive TT position. Think Floyd Landis around 2006. That position worked very well for a number of riders. And like Floyd himself, it was also outlawed by the UCI....

The Praying Landis - A positively dope TT position.
The initial checks were to ensure the rider's forearms were horizontal when they were on their bike and in their TT position. This check was invalidated by the new bike check process introduced in 2014:   

....from 2014, only the bicycle will be checked. The bicycle can be presented by a person other than the rider. This will mean that riders are not disturbed in their preparations just before the start of the race. - UCI Update Info Bulletin N°4

To ensure riders were adhering to the rule without being present, a -+10cm rule for the TT bars/extensions was detailed:

"The height differences between, on the one hand, the point of support of the elbows and the highest point of the handlebar extension (including the gear levers) and, on the other hand, point of support of the elbows and the lowest point of the handlebar extensions (including the gear levers) shall each be less than 10 cm in order to guarantee that the forearms are horizontal." - UCI Update Info Bulletin N°4

It appears the most recent update/clarification has no reference to horizontal forearms as bike with a +10cm measurement means the riders forearms won't be horizontal (although they'll be far from being a Praying Landis):

The handlebar extensions plus any accessories (controls, levers, etc. and all their mounting accessories) must be within ±10 cm from the level defined by the elbow/forearm supports. Any moving parts have to be placed in the most vertical position that can remain unsupported through their range of movement. - The Clarification guide of the UCI Technical Regulation - August 2014

The UCI have included some excellent diagrams in their August 2014 Clarification Guide:

To check, rotate the levers to the highest point and allow to rest, and then take the measurement for the +10 cm position. If necessary, rotate the lever to the lowest point and take the measurement for the -10 cm position. The measurements of the upper and lower limits are taken in the front half of the handlebar extensions. - The Clarification guide of the UCI Technical Regulation - August 2014

Subtle but important detail there - Taking the measurement point from the highest point of the lever puts riders with most mechanical levers at a disadvantage if they're after maximal lever height. Chalk that up as a reason to investigate electronic shifting on a TT bike.

So is the praying mantis back? No. It'll be interesting to see if Cycling Australia have a jig that can measure this at the Nationals in a few weeks...

In the mean time, if you're "pushing the limits" pack some spacers or extra chunky arm pads to raise up the measurement point of the armrests.... or adjust your rear limit screw to stop your levers from reaching >10cm. You'll lose 1-2 gears on the rear, but you won't get a DSQ for the event.

"Factory" measurements with DuraAce levers. Hmm!

Sorted - Beanbag arm pads, UCI legal!

No comments: