creamsickle Posted May 19, 2006 Report Share Posted May 19, 2006 so my sisters shee is stock except for like reeds pipes and a filter. we ride at sea level. I took the compression and its like at 105 for each cylinder. Ihave no idea what stock compresion is. never owned a stock shee haha. Quote Link to comment Share on other sites More sharing options...
gregbowler Posted May 19, 2006 Report Share Posted May 19, 2006 Should be around 135 Quote Link to comment Share on other sites More sharing options...
Nighty Posted May 19, 2006 Report Share Posted May 19, 2006 Make sure you use the right fitting for your compression tester. If the fitting is shorter then you spark plug the volume in you cilinder will be bigger. thus your compression will turn out lower then it actually is. also. when testing the engine should be heated up and full trothle must be applied. Leave the ignition off i say compresion should be 125 psi. Quote Link to comment Share on other sites More sharing options...
hittintrees srh Posted May 19, 2006 Report Share Posted May 19, 2006 Make sure you use the right fitting for your compression tester. If the fitting is shorter then you spark plug the volume in you cilinder will be bigger. thus your compression will turn out lower then it actually is. also. when testing the engine should be heated up and full trothle must be applied. Leave the ignition off i say compresion should be 125 psi. 517958[/snapback] r u sure you want it heated first? i thought do it cold so your rings havent expanded yet correct me if im wrong-if i am ill retest my comp. Quote Link to comment Share on other sites More sharing options...
ssanddemon Posted May 20, 2006 Report Share Posted May 20, 2006 Yep, do it hot. Throttle wide open, ign switch off and kick it till it maxes out. Quote Link to comment Share on other sites More sharing options...
creamsickle Posted May 20, 2006 Author Report Share Posted May 20, 2006 well doing it hot wont do me any good right now cause the right side isnt firing haha. but I guess I can warm up the left sylinder haha. so you say throttle open even when its off? like when you are kicking it over with the ignition off? Quote Link to comment Share on other sites More sharing options...
ssanddemon Posted May 20, 2006 Report Share Posted May 20, 2006 well doing it hot wont do me any good right now cause the right side isnt firing haha. but I guess I can warm up the left sylinder haha. so you say throttle open even when its off? like when you are kicking it over with the ignition off? 518285[/snapback] Well if you are doing a comp test because of a dead hole, don't bother warming the bike up- if you don't get at least 100 psi, the cyl won't even fire. Anything less than 110 is on the train to wornoutsville. Warm cylinders typically read 5-10 psi more, and are more accurate- hot is the natural state of the engine and you want to measure the engine as it is when being run. By the same token, You want the throttles open to get max air into the cylinders. A proceedure is only good if it follows certain rules, and throttle open is a given on any comp test- otherwise you are testing compression relative to your idle stop settings, which are gonna be different on any bike. Quote Link to comment Share on other sites More sharing options...
scotts96fast Posted May 20, 2006 Report Share Posted May 20, 2006 Hmmm I was always told to check it cold....I have check it warm before and only got a pound or 2 higher. Quote Link to comment Share on other sites More sharing options...
RIPPEN Posted May 20, 2006 Report Share Posted May 20, 2006 I checked mine cold... I was told to do that from my engine builder RIPPEN Quote Link to comment Share on other sites More sharing options...
awesomeame Posted July 9, 2006 Report Share Posted July 9, 2006 i checked mine today. cold, throttle closed. only 90psi, but both cylinders were the same so i guess that's good. it runs just fine, but i'll be doing a top end this coming winter. once i get the quad back together i'll test it again hot with the throttle open and see what it says. my compression tester fitting is only about 1/3 the length of the spark plug, so that'll lower the psi a bit too, usure how much though....not like i'm racing or anything though, it runs well and that's what i want. --matt Quote Link to comment Share on other sites More sharing options...
Recommended Posts
Join the conversation
You can post now and register later. If you have an account, sign in now to post with your account.