Cranking Compression 09 RULES
Cranking Compression:Effective May 15, 2008, we are changing the maximum cranking compression on a 1200cc unsealed engine to 165 lbs - tested in accordance with the current INEX Rulebook. This cranking compression closely resembles the cranking compression of a stock Yamaha 1200cc engine. If your 1200cc engine pumps more than 165lbs, it is a quick and simple fix by adjusting the cam timing on your slotted cam gear or adjusting the valve shims. Illustrations of the slotted cam gear can be found at www.600racing.com. If you need additional assistance with this procedure, please contact 600 Racing.
Correct Cranking Compression Rule By Inex
BRIAN,here is the 09 rule on cranking compression right from 09 rulebook,8. 1200 CRANKING COMPRESSION:
The cranking
compression of an un-sealed engine must be at or below
165 p.s.i. at anytime (hot or cold) on at least three (3)
cylinders with the ignition off and the throttle wide open
with the carburetors on the engine, and all four spark
plugs out. Ten to twelve revolutions of the engine will
determine the total compression of a cylinder. Cam timing
may be adjusted accordingly to meet the requirements of this
rule by slotting the cam sprocket gear or substituting with an
aftermarket cam gear sprocket. INEX highly recommends that
you have your engine set at 155lb. cranking compression instead of
right on the line at 165 lb. to allow for slight variations between
gauges. There is no tolerance for engines over 165 lb. and the
gauge used by the tech inspector is the “official gauge".
This is the rule right out of the INEX RULEBOOK 09..If RIVERHEAD is an INEX santioned track ,THEY should use these rules...........KEVIN 53ny:wave: