03banshee20 Posted March 13, 2011 Report Share Posted March 13, 2011 2003 banshee has fmf sst pipes and slencers. vf3 reeds. has low compression did a compression test today only had 115 in both cylinders. was just rebuilt with new yamaha pistons and has stock bore. motors only been apart twice. Quote Link to comment Share on other sites More sharing options...
06specialedition Posted March 13, 2011 Report Share Posted March 13, 2011 2003 banshee has fmf sst pipes and slencers. vf3 reeds. has low compression did a compression test today only had 115 in both cylinders. was just rebuilt with new yamaha pistons and has stock bore. motors only been apart twice. Whats your elevation? Stock head I assume? Quote Link to comment Share on other sites More sharing options...
03banshee20 Posted March 13, 2011 Author Report Share Posted March 13, 2011 Whats your elevation? Stock head I assume? yeah stock head and 480ft Quote Link to comment Share on other sites More sharing options...
jasons Posted March 13, 2011 Report Share Posted March 13, 2011 yeah stock head and 480ft sounds good to me run the piss out of it. Quote Link to comment Share on other sites More sharing options...
06specialedition Posted March 13, 2011 Report Share Posted March 13, 2011 sounds good to me run the piss out of it. Yeah you should be okay. With a stock head at sea level you should be running around 130ish. Look at the bottom of this page, it will kinda give you an idea of different compressions: http://www.nossmachine.com/banshee_heads.htm Quote Link to comment Share on other sites More sharing options...
muggzy Posted March 14, 2011 Report Share Posted March 14, 2011 2003 banshee has fmf sst pipes and slencers. vf3 reeds. has low compression did a compression test today only had 115 in both cylinders. was just rebuilt with new yamaha pistons and has stock bore. motors only been apart twice. Has your rebuild been broken in yet? Your compression will go up after a proper break-in. Quote Link to comment Share on other sites More sharing options...
Jereme6655 Posted March 14, 2011 Report Share Posted March 14, 2011 2003 banshee has fmf sst pipes and slencers. vf3 reeds. has low compression did a compression test today only had 115 in both cylinders. was just rebuilt with NEW YAMAHA PISTONS and has STOCK BORE. motors only been apart twice. So...did you have it honed out? Did you have it bored out? my questions is how did you do a full REBUILD if your running new STOCK sized pistons. if your running stock sized pistons then i doubt it got bored out....which means that even though you have new stock pistons in there...your cylinders are going to have a natural wear curve in the jugs. It happens to every single cylinder.....it winds up having a very very very slight egg shape to it....you can only tell by meausring it with a micrometer.....but boring it is what removes the shape and brings the jug back to correct shape...which in turns helps with compression by replacing the pistons with correct new bore sized pistons. Sounds to me like your a little low because your rebuilt with stock sized pistons. Either way if you have 115 id still run the shit outta it... Quote Link to comment Share on other sites More sharing options...
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