pmieras Posted June 25, 2011 Report Share Posted June 25, 2011 Let me introduce myself briefly.... New to the banshee world. Have been lurking for a bit and there is tons of great information on the site... I purchased a 1999 banshee a few months ago and am now experiencing some starting issues. Once I get the motor started and warmed up, it starts just fine, no issues. I just did a compression test. From cyclinder to cylinder cold the compression is just over 40psi, once I get it started it drops to about 35 with a warmed up engine, seems a little low. I was expecting somewhere around 90+ psi. So at this point I'm leaning towards a top end rebuild. Haven't done a leak down test yet. Have to build the gauge first but will probably to the leak down test prior to deciding on the topend rebuild, just to make sure. Mods on the quad are as follows: T5 pipes, Air box drilled and aftermarket filter (I believe UNI) . Previous owner told me it was jetted as well (I'm assuming it was one of the kits that you can get from Toomey). Checked spark plugs and everything appears to be good. Slight tan color to the electrodes of both spark plugs and good strong spark (bright blue). Doesn't appear to be rich or lean. Don't believe there is any porting. I run 91 octane gas and a 32:1 ration mix of redline. I think that's just about everything... Any other suggestoins would be greatly appreciated. I think I'm on the right track though. Quote Link to comment Share on other sites More sharing options...
coryv4 Posted June 25, 2011 Report Share Posted June 25, 2011 Let me introduce myself briefly.... New to the banshee world. Have been lurking for a bit and there is tons of great information on the site... I purchased a 1999 banshee a few months ago and am now experiencing some starting issues. Once I get the motor started and warmed up, it starts just fine, no issues. I just did a compression test. From cyclinder to cylinder cold the compression is just over 40psi, once I get it started it drops to about 35 with a warmed up engine, seems a little low. I was expecting somewhere around 90+ psi. So at this point I'm leaning towards a top end rebuild. Haven't done a leak down test yet. Have to build the gauge first but will probably to the leak down test prior to deciding on the topend rebuild, just to make sure. Mods on the quad are as follows: T5 pipes, Air box drilled and aftermarket filter (I believe UNI) . Previous owner told me it was jetted as well (I'm assuming it was one of the kits that you can get from Toomey). Checked spark plugs and everything appears to be good. Slight tan color to the electrodes of both spark plugs and good strong spark (bright blue). Doesn't appear to be rich or lean. Don't believe there is any porting. I run 91 octane gas and a 32:1 ration mix of redline. I think that's just about everything... Any other suggestoins would be greatly appreciated. I think I'm on the right track though. HOLY FUCK!!1!!!11!!!! 40psi???????????????? last i checked a stock banshee should be around 120- 130 you better find a diff compression tester cause that dont sound right Quote Link to comment Share on other sites More sharing options...
coryv4 Posted June 25, 2011 Report Share Posted June 25, 2011 i would start off with a diff tester just to make sure then if you still get the same numbers id rebuild the topend bore it .010 over if needed but id for sure get new pistons and rings.. Quote Link to comment Share on other sites More sharing options...
patsbansh Posted June 25, 2011 Report Share Posted June 25, 2011 I had no idea that they would run at such a low compression. If you have access to another compression tester try again. i re ringed my buddy's 06 when it got down to 95 PSI and the second time it got down that low i ran a ball hone through the cylinders lightly just to clean them up and went with a 64mm wiseco prolite kit, if the cylinders don't need to be bored why do it, prolong the life. I have an 03 with 64mm stock cylinders a cool head, timing advance V Force 3 reeds and some other slight mods and it still rips and i have put alot of hours on it since i put virgin cylinders on 3 years ago and i still have 134 PSI as of a month ago Quote Link to comment Share on other sites More sharing options...
banshee_R1 Posted June 25, 2011 Report Share Posted June 25, 2011 Dont even bother with a leakdown yet rebuild it!!!! Quote Link to comment Share on other sites More sharing options...
shakar Posted June 25, 2011 Report Share Posted June 25, 2011 def......get/try a new comp tester Quote Link to comment Share on other sites More sharing options...
Larry's Shee Posted June 25, 2011 Report Share Posted June 25, 2011 Fuel off, throttle wide open, kick until gauge stops moving (10-15 kicks). Screw in gauge with threads same length as plug. Quote Link to comment Share on other sites More sharing options...
pmieras Posted June 27, 2011 Author Report Share Posted June 27, 2011 So confirmed with a second gauge and compression a little better but still bad. Checked with fuel valve off first as suggested, then on. Not a whole lot of difference to my surprise. Anways, I'm expecting the worse and may have to bore out bigger. Would I have to rejet if I have to bore bigger? Quote Link to comment Share on other sites More sharing options...
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