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yz250 Cylinder temp

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Hey all,

This may be a dumb question, but how hot should your cylinder be under operating temps? I recently touched my cylinder on accident with my finger and it burned the crap out of me. Is this normal?

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Hey all,

This may be a dumb question, but how hot should your cylinder be under operating temps? I recently touched my cylinder on accident with my finger and it burned the crap out of me. Is this normal?

Depends how hard you were riding right before you touched it, But i can usually touch my cylinder for a few seconds during normal riding without it burning .

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Depends how hard you were riding right before you touched it, But i can usually touch my cylinder for a few seconds during normal riding without it burning .

I warmed it up and took it around the neighborhood a few times.

 

This makes me worried - how would I got about checking my cooling system?

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Hot enough to burn your skin


I warmed it up and took it around the neighborhood a few times.

 

This makes me worried - how would I got about checking my cooling system?

 

I would first make sure that it is jetted rich enough

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I warmed it up and took it around the neighborhood a few times.

This makes me worried - how would I got about checking my cooling system?

take the radiator cap off and start it up you should see coolant flowing in the radiators. If that checks out check for air leaks that could be leaning it out.

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The general consensus is between 155-175F. Which makes it pretty toasty to the touch. If i remember, ill take the ol temp gauge out this weekend and give a typical temp.

 

Jetting, air leaks, low coolant, and a bad pump are common things that go haywire. Good info above. Also good info if you search on TT.

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Thanks for all the tips, I recently moved from a 32:1 to a 35:1 premix ratio but made no other changes. I'll move back to 32:1 and see if that does anything.

 

I'm going to be swapping out some parts and doing an oil change this weekend, Ill be sure to check the radiator fluid to make sure things are moving. Thanks for all the tips.

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I was takin it pretty easy today and my outside cylinder temp was hot to the touch but sat around 120deg. Just for the record i suppose.

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Buy some temp strips or a temp gun. Right now everything is just arbitrary with nothing to back it up. "Burned the crap out of me" doesn't tell if it's 140 degF or 5000 degF.  

 

General acceptance is that prolonged touching of a 110-112 degF object is where most people start to feel pain. Around 160-165 degF is where it's going to hurt with even a quick dab. Lots of variables, such as pressure, surface area in contact, etc. You can wet a finger and swipe a 600 deg cook surface without issue, just as an example of the great variation at play here. 

 

 

I'd check coolant and yes, make sure it's flowing. A change from 32:1 to 35:1 is nearly nothing to your engine, I wouldn't sweat it. 

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