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2003 Honda cr250 compression question.

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So checking my compression on my 03 cr250. Gauge goes to about 175psi and settles to around 152psi. I'm in Colorado so elevation is higher here, but what do you guys think? Is compression ok for now? Just got done with an iron man 12hr race and going through everything. What's everyone's thoughts?? Good or bad? Or fine for a few months till snow kicks in and I don't have to miss any riding?

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Is it a good gauge that's accurate ?  Did you hold the throttle open ?   That seems low to me & not worth the risk of having a failure especially if your running a cast piston. Once you get certain hrs. on a cast piston due to the heat cycles it starts to show stress cracks & the skirts normally let go.  I've seen some carnage through the years & always suggest going to a forged piston to riders.   Do you know aprox. how many hrs. the topend has ?   

Edited by H4L

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Yes it's a snap on gauge I trust it. Yes held throttle wide open. Couldn't not tell you on how many hours the motor has on it before I got it. But I have put 30 solid Hours on it. I'm a strong B rider. So it's not like it's best to shit. Just wanted some opinions. Just sucks I'm going to have to do it now. Most likely I'll have to send cylinder off. I'm hoping not but we will see.

Thank you for your input though!!

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Another good indicator for me has always been how the comp. feels when I'm kicking it over.  After many yrs. you get an idea of how the comp. feels with a fresh topend & at about the 50 hr. mark you can feel the difference.  I've also been running an hr. meter on my 2t's since 05 after using one on a crf450r I thought it was a good way of keeping hrs. for service intervals.     

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Another good indicator for me has always been how the comp. feels when I'm kicking it over.  After many yrs. you get an idea of how the comp. feels with a fresh topend & at about the 50 hr. mark you can feel the difference.  I've also been running an hr. meter on my 2t's since 05 after using one on a crf450r I thought it was a good way of keeping hrs. for service intervals.     

Ya I put one on when I got the bike to keep track of everything I did to the bike. Everything has been replaced except for motor components. So I guess I will dive into the motor now. Yes compression is hard for me coming from a 4 stroke so 2 strokes kick to me like nothing haha

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17 hours ago, Zumpy31 said:

 

 I'm in Colorado so elevation is higher here, but what do you guys think? Is compression ok for now?

 

Always look over the engine and piston for condition but at what elevation are you riding? To my understanding an engine with 200 psi compression at seal level would lose something like 20+psi at 5000 feet and even more as you go up. A stock 03 with a fresh rebuild is very close to 200 psi compression if not more, it's what I've seen with forged pistons at least.

 

My last top end was done at a compression loss of 18 psi from around 210 psi and I live around 320 feet above seal level.

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Always look over the engine and piston for condition but at what elevation are you riding? To my understanding an engine with 200 psi compression at seal level would lose something like 20+psi at 5000 feet and even more as you go up. A stock 03 with a fresh rebuild is very close to 200 psi compression if not more, it's what I've seen with forged pistons at least.
 
My last top end was done at a compression loss of 18 psi from around 210 psi and I live around 320 feet above seal level.

I ride anywhere from 6000 + feet I'm in Colorado Springs. So mountains are higher.

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1 minute ago, Zumpy31 said:


I ride anywhere from 6000 + feet I'm in Colorado Springs. So mountains are higher.

Well take into account the elevation, I'd say your losing 25 psi at elevation from a fresh top end that could be anywhere from 200 to 210 psi. So this leads me to question, did check your rebuild compression when you started and what was it putting out? 

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I didn't rebuild the motor. That's why I'm asking how the compression seems the way it sits. I have put 30 hours on it but I don't know how many hours it had prior to me getting it.

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