Wsbk rules change..

[MIGHTY MAX]

WSBK 2011 Rule Changes Include An End To Aprilia's Gear-Driven Cams

Submitted by David Emmett on Sat, 2010-07-31 21:33.

 

As is common at world championship motorcycle racing events, the Superbike

commission - the World Superbike series' rule-making body - gathered to

discuss rules to be introduced for the 2011 series. After the meeting, a press

release was issued detailing the changes to be made for next season, and

they make interesting reading.

 

The biggest change was the scrapping of the loophole which has allowed

Aprilia to drive the camshafts on their RSV4 World Superbike machines using

gears instead of the chains fitted on the production bikes. The rule had

originally read "The method of cam drive (chain, belt or gears) must remain as

on the homologated motorcycle unless a complete kit is available through

normal commercial channels" but the last part of the sentence - "unless a

complete kit is available through normal commercial channels" - has been

dropped.

 

Aprilia's use of gear-driven cams has been controversial from the start. The

original cylinders are supplied with the machining required to fit the gear drive

as standard, but use a chain drive to keep production costs down. The

Aprilia's V4 configuration makes this even more costly, requiring two sets of

gears for each bank of cylinders, and so fitting gear-driven cams to the road

bike would add considerably to the basic price. Fitted as an aftermarket race

kit, the gear-driven cams allow the RSV to attain higher revs and allow for

more precise cam timing. The RSV4 has been fast from the

start of the season, but since the Alitalia Aprilia started using the gear drive,

the disparity with the other bikes has grown.

 

To put an end to the arguments, the Superbike Commission has prohibited

fitting aftermarket kits, and all World Superbike machines must use the cam

drive fitted as standard. Of course, this does not prevent Aprilia from using

gear-driven camshafts completely, but it does require that the RSV4 be sold

with the gear drive as standard, something which Aprilia may be less keen to do.

 

(Titanium Rods and two sets of cam gears are some of the reasons why the

RC45 cost so much...)