dajogejr Posted January 11, 2008 Report Posted January 11, 2008 Generally...when the compression is that low, it doesn't start first kick... Mine took a few when it was at 110 or 105... Do yourself a favor, try another compression gauge, just so you don't waste your time tearing it down... Cheapo tester gauges can be WAY off...I've seen as far as 10 to 35 PSI off... If it's a quality gauge, then it's time to freshen up. Quote
shee4speed Posted January 11, 2008 Report Posted January 11, 2008 ^^^^^^^^^ Thats good advice. I wonder what tester he is using. Quote
AJC Posted January 11, 2008 Author Report Posted January 11, 2008 Napa something Professional guage. i popped into my local automotive garage and got it done. so i guess its a good guage.. ill try another guage before tear down just to be on the safe side.. and yep. she sure does start on first kick.. even when shes cold. pull out the choke and first kick. Quote
dajogejr Posted January 11, 2008 Report Posted January 11, 2008 If you have the money, get a complete craftsman tester gauge... Warm the bike up, then check.. Remove both spark plugs, test one cylinder at a time, and KEEP KICKING until the gauge no longer rises. It can often take 20 to 30 kicks...some people stop after 10 kicks....and get an inaccurate reading. Quote
AJC Posted January 11, 2008 Author Report Posted January 11, 2008 (edited) test it when the motors hot? umm i didnt do that.. i done it when she was cold.. in minus 3 degree weather. does that have any affect on the reading?.. being cold? Edited January 11, 2008 by AJC Quote
dajogejr Posted January 11, 2008 Report Posted January 11, 2008 Usually you'll gain some PSI.... A hot motor is sealed better, expansion and all the fancy stuff. Normally...a worn motor will be a bit less cold than hot. A fresher motor, not as much of a difference. Quote
AJC Posted January 14, 2008 Author Report Posted January 14, 2008 done another test with a different tester and only came up to 70psi... so i went and ordered a wiseco piston kit.. but i need help with ordering the wrist pin bearing... i ordered the kit that i have marked in red. but on the left is what i need help with. the pin bearing. i dont know which one to order. any help? Quote
AJC Posted January 16, 2008 Author Report Posted January 16, 2008 got this figured out. would it be the best idea to break in the top end in minus 5 or so temps?.. or just install pistons. check compression and let it be till spring time? Quote
TJ10 Posted January 16, 2008 Report Posted January 16, 2008 I have the Noss head with 20cc domes and run 93 octane gas. When I put it on, I checked the comp. and it read 75psi in one cyclinder. I know that is not correct so I just said fuck it. Runs great with 93 with no predetonation. I'll probably get it checked this spring with a better tester just for my future reference. Quote
AJC Posted January 16, 2008 Author Report Posted January 16, 2008 ya, im going wait untill the summer sometime to get the nose head and stuff.. just wondering now if its a good idea to do a rebuild in this cold weather were having. Quote
DILUSI Posted February 23, 2008 Report Posted February 23, 2008 If you have the money, get a complete craftsman tester gauge...Warm the bike up, then check.. Remove both spark plugs, test one cylinder at a time, and KEEP KICKING until the gauge no longer rises. It can often take 20 to 30 kicks...some people stop after 10 kicks....and get an inaccurate reading. dont you have to also plug up the exhaust for the jug thats being tested and have the throttle wide open when doing a comp. test? Quote
shee4speed Posted February 23, 2008 Report Posted February 23, 2008 Just wide open throttle. No need to plug the exhaust. Quote
bunboy1 Posted February 23, 2008 Report Posted February 23, 2008 can you test the compression with the carbs off? right now my motor is on a mini pallet. i plan on tying it down to the pallet with a ratchet strap and kicking it over for the compression test. what do you all think? thanks Quote
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