top end refresh and jetting question
Re: top end refresh and jetting question
Nice one buddy
Re: top end refresh and jetting question
Hi, sorry mate, but could you run another compression test on it now she's new? I think mines a bit down, I got about 82psi, I'm aware two strokes run lower compression than a four stroke anyway, but my TTR 265 is pushing out about 135-140PSI, and the revs are hanging a bit when I rev it up in neutral and let it settle, the plug says it's jetted fine but my heart says something's up.
I might just put a new piston in her anyway.
I might just put a new piston in her anyway.
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Re: top end refresh and jetting question
82psi is way low! Book for the AR says 177psi so you could be down 50% mine read 125psi before rebuild. not tested since but big difference in power.Fladdem wrote:Hi, sorry mate, but could you run another compression test on it now she's new? I think mines a bit down, I got about 82psi, I'm aware two strokes run lower compression than a four stroke anyway, but my TTR 265 is pushing out about 135-140PSI, and the revs are hanging a bit when I rev it up in neutral and let it settle, the plug says it's jetted fine but my heart says something's up.
I might just put a new piston in her anyway.
viewtopic.php?f=6&t=9848
- chris1971
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- Bike Owned: crm mk2,2
- Location: sunny fife , scotland
Re: top end refresh and jetting question
82 Psi is frightingly low mate . tested the compresion last night andTBH my old tester is not at its best . 4 different readings but all above 180 psi . seems high to me but the new piston size is far bigger now . kicking my mk2 crm is near enuf the same kind of compresion i get from my 89 cr 250 . not quite as strong but not far away . only way to tell with your bike is to nip the barrel off and get the bore wear measured mate . i got away with a quick hone and a new set of rings with mine after i first bought her . the rings that came out were worn so badly you could actually see a thick and thin part to them . good thing is if you have a mk2 the cylinder liner is cast and can usually outlast a set of rings for wearing downFladdem wrote:Hi, sorry mate, but could you run another compression test on it now she's new? I think mines a bit down, I got about 82psi, I'm aware two strokes run lower compression than a four stroke anyway, but my TTR 265 is pushing out about 135-140PSI, and the revs are hanging a bit when I rev it up in neutral and let it settle, the plug says it's jetted fine but my heart says something's up.
I might just put a new piston in her anyway.
- Bultacobob
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Re: top end refresh and jetting question
Hi Mk MK3 with 4000 miles was about 175 psi, Just been checking my dr350 and it was about 40 psi checked it again with a decent gauge and it read about 35 psi better. The first tester was from E bay enough said the, second a Gunson form Halfords. Your Bike should be about 160 -180 in great condition but would be OK in the 150 range.