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I have a 04 crf250r I rebuilt and the timing is off by a tooth its broke in and all. It has a higher comp piston and it seemed to run hotter would it run hotter cause valves are off or just the compression cause it?

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I have a 04 crf250r I rebuilt and the timing is off by a tooth its broke in and all. It has a higher comp piston and it seemed to run hotter would it run hotter cause valves are off or just the compression cause it?

 

fix the timing. its really easy. okay. just fix it.

the cam gear is a 36 tooth gear, thats 10 degrees of advance or retard per tooth 360/36=10

the stock cam probably has 1-5 degrees of advance built in. so you could be at 11- 15 degrees advance or 5-9 degrees retarted.  it wont run well like this. and if its retarted, a valve can be bent more easily if valve float occurs.  It could run rich because the intake closes late and reversion is more likely.

if its advanced, you will be opening the exhaust early, way early, while chamber temps are still higher, and closing the intake earlier than optimal for intake ramming.

 

so just line up your timing marks and let er rip.  2 degrees makes a difference you can feel, 10 is too much man!

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OK I mean its still got the bottom end power but I never wound it out cause the new parts. It prob is shutting exhaust too soon that's why its a little hot. Thanks tho. I won't take the cam out to adjust this time I'll just slide a little screw driver between the teeth and chain

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OK I mean its still got the bottom end power but I never wound it out cause the new parts. It prob is shutting exhaust too soon that's why its a little hot. Thanks tho. I won't take the cam out to adjust this time I'll just slide a little screw driver between the teeth and chain

 

no closing the exhaust too soon would not be a reason for higher operating temps.

how would i know? I have a camshaft grinding machine, and i have worked on race every things.

Edited by englertracing

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Why would you even consider riding it like that????

WHEN you grenade the top end, please don't list it on craigslist as "fresh rebuild, just needs new motor".

you can run an engine when the timings off by a tooth

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you can run an engine when the timings off by a tooth

 

Ya, but they always run like the proverbial bag of s**t . You  sure it's out of time , overheating could be sometime else.

Edited by bucket list

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Well it runs but it idles high then slowed down and quits plus the flywheel measures its off. Its a little more simple with sohc dohc is a little harder to adjust

I'm guessing its intake opens too soon and the exhaust shuts early it also has higher comp piston which may cause more heat

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Dude these bikes are simplest motors to time stop typing on here and take the 45 minutes to time your bike use the hash mark to the right on the fly wheel and the hash marks on  the cam should be in line with the head easy stuff 

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I already did and I said it had one cam I meant its easier than my dohc bikes I know how to adjust. I was just asking if it'd hurt it didn't run as hot before rebuild I bought a yz 426 with off timing and fixed it myself I just didn't know of it would hurt my crf to have been broke in off by one tooth

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I rebuilt it in a few hours I do engine rebuild and suspension as a job but I never owned a Honda unicam. I owned one of their dohc bikes and it was very reliable

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Im sorry but if you do engine and suspension rebuilds as your job and ask if running the timing off from ehat its supposed to then maybe you need more schooling or to watch someone do it first. I know if i took a bike to some one that had to ask online about it that i wouldnt trust that one bit. Now i understand everyone starts somewhere but i wouldnt ask that question then state you do it for a living.

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I've been doing it it a year I never had schooling or anyone teach me any thing so I'm still new but I've never had an unsuccessful rebuild yet

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Everyone's gotta start somewhere. But atleast you asked the question rather than doing it and have something break and be back to square one.

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Yeah I've never had trouble with regular engines like xrs and ttrs I usually mark the can and chain to match up for assembly but I put a new crank in this one so it was a little difficult. I also learned the marking on the flywheel and can won't match up perfect but it runs good now

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Good yea those xrs and ttrs a blonde women could put together that's what I loved about them and they are tanks.

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