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Hey,
I have a 2008 CRF230F, brand new, got it in december as an upgrade from my 150. It has about 12 hours on it and it is still running really hot. The tranny case is about 210 degrees after a half an hour of riding and not screaming but higher rpms. The head is extrememly hot. Anyone else having the same heat problems??

from the factory they run very hot.
there are some videos on youtube where they turn out the lights and the header is red hot

this is caused most in part by the bike being jetting very lean from the factory.

a re-jet should be the first thing to do on the bike before anything else.

do a search on it.

what elevation are you at?

im at sea level up to about 3K ft.
and i run:
120main jet

45pilot jet

stock needle 4th clip down ('04 needle has more adjustment than yours, for you it would be the lowest clip or you can source an '03-'05 needle offline and get more adjustability)

fuel screw 1.5-2 turns out from fully seated

air-box snorkel removed

aftermarket exhaust(but removing the baffle on the stock exhaust/drilling a hole in the stock exhaust baffle for reduced noise has the same effect)


let me know if you have any questions about this procedure.

I have rejetted the bike and if anything it is running just alittle rich. I have uncorked the air and exhaust. I have a 110/112, i don't remember what, and I color tuned it. I was just wondering if it is normal to run hot even the it is jetted correctly.

110/112 seems abit lean compare to what others have learned, though depending on elevation, you may be okay. What elevation are you at?

I run a 120 main/stock needle in 4th position/48 pilot with a lot of fiddling using an adjustable idle fuel screw (kouba) here at sea level with airbox and exhaust uncorked.

they do run hot

but they run even hotter when jetted lean

The 112 Main Jet is what is listed as the richer main in the Honda Part Catalogue.

If you have removed the snorkel from the top of the airbox and removed the baffle put at least the 120 main in and move the clip to the richer position and see how that goes.

What does the plug look like?

It is aircooled and they do run hot once warmed up.
I never actually measured the head temp but since your measurement is the transmission case I have to ask is the oil level correct and does it smell burnt or normal?

I am at 7100 feet. i sometimes ride up to about 8000 feet.