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I have a crf450r and it runs hot when I get on it. I can ride it maybe 10 minutes and starts running hot. It is also really hard to crank, but once its been cranked it easy to crank back up. When cold I have to kick it maybe 30 time before it starts. It also pops for the first minute after being cranked. Is there anything I can check to fix these problems? The carb. Has be re jetted and cleanded well.it leaks anti freeze out over flow hose. When it runs hot[/img]

first, the starting issue could be the carb and/or tight valve clearances. check the clearances first. if they are good then you'll need to look into the carb (pilot jets, fuel screw, AP, and floating valve seal are typical culprits.)

as for the over heating it could be a lean condition with your jetting, type of coolant you are using, head gasket, water pump or other issues. check your engine oil make sure it is clear and at the correct level. are you loosing coolant before it overheats?

ken

Yes it starts leaking out the over flow hose before it runs hot. I honestly don't know if its even running hot I just know it leaks out the hose after riding for a few minutes

First, check all the hoses and make sure none are kinked or pinched off. If not, I'd drain the coolant and then pull the radiators and hoses and check for any obstructions in the hoses and radiators. If all is good then you should pull the water pump cover and inspect.

Ken

Ok great I will try all of this and get back to you.. thanks for the help

Start with the simple and try a new radiator cap. They are supposed to lose a little otherwise there would be no need for a drain hose. As for your starting, have you tried different methods of starting? I know on mine if you don't follow it's own particular drill it can be a beast to start, if you do what it likes it will start 1st or 2nd kick every time.

What do you do to yours to make it crank easy? After its warm it cranks 1st kick... I will try cap first though thanks

On mine the drill is to choke, give one twist on the throttle (two or three if it's cold out), and kick the snot out of it. I've had two of these bikes and they both had to be started completely differently. On the other one sometimes I had to drain the bowl a little to get it to light if it had set for a few days or more.

I will try that. My choke when I pull it though it goes right back in. Shouldn't it stay out? Maybe I need a new choke on it

kenny304304 wrote:I will try that. My choke when I pull it though it goes right back in. Shouldn't it stay out? Maybe I need a new choke on it

That's most likely your problem then, try working it in and out a few times maybe your detention that holds it open is gunky. I'm not sure if there is a seal in there or not that holds it out but you should feel a solid "snap" when you pull it out.

Awesome thanks for the help