Hi what should be the squish setting for a runner 172 with a kb billet racing head?? 0.8mm to 1.0mm?? Its got a bgm 52 crank. any answers would be much appreciated Thanks
personally i would stick to 1 to 1.4mm (obviously depending on how much i want to squeeze from the engine), there is a topic about 70 squish settings on here, it's the same principal just with a physically bigger engine.
the heads are higher compression (hope your not running the one for the 54/55 stroke) you need to set the squish verry loose on those on an unported head or you get lots of predetonation.. high comp heads are made to combat the compression lost to a higher exhaust port (ported barrel) with a stock barrel it makes around 12:1 mathmatical compression ratio wich is way too hgih for road fuel so drop the squish to around 1.8/2.2mm. it wont burn correctly at a higher compression.
Im using the correct one for the 52 stroke crank. http://scooter-center.com/catalog/produ ... 2_314_4319 This is the exact same one as i have.
