riding an mx bike on trails...?

ok, so i just bought myself an 03 yz450f..ive done all my previous riding on 2 strokes though..none on these big thumpers..ive had the 125's and 250's out on the trail and thats all i rode..i hear though that these mx four strokers "over heat on the trails" "gotta wait 20 mins before starting it hot again"..this bike is all stock and will stay that way..these 450's have plenty of power out of the box..nothing needed for more speed or torque..so my question is..will this bike be a bear to ride on the trails from an "over heating" stand point?,..is this just some people's opinion?..any help is appreciated thanx-josh

No... Not that I've seen, but you'll want to stay on top of your coolant level and mixture.

Hot starting can be a bytch, but you'll find the formula after a while.

Most guys add a flywheel weight to help with stalling in corners and smooth the power a bit and drop to a 13 tooth front sprocket, so you can stay away from 1st gear a bit more. And that's about it except you might want to go ahead and order a few extra rear fenders:p

It all depends on you! If you're not a fast trail rider and you hit some real technical stuff for extended period (1st gear stuff) you will overheat! My bike overheats if I let it idle too long. Things that will help: slightly higher psi radiator cap, engine ice and if you are still having problems bigger radiators. Of course forcing yourself to ride faster in the technical stuff!

ok, so i just bought myself an 03 yz450f..ive done all my previous riding on 2 strokes though..none on these big thumpers..ive had the 125's and 250's out on the trail and thats all i rode..i hear though that these mx four strokers "over heat on the trails" "gotta wait 20 mins before starting it hot again"..this bike is all stock and will stay that way..these 450's have plenty of power out of the box..nothing needed for more speed or torque..so my question is..will this bike be a bear to ride on the trails from an "over heating" stand point?,..is this just some people's opinion?..any help is appreciated thanx-josh

thanx alot for the help guys! sounds like i should be ok with not over heating..i rarely ride slow..as you said, only in technical spots..most of the riding is fast so looks like i'll be good..and i cant really afford to dump any more money into the bike because the previous owner laid it down and i had to buy new radiators left and right because these were bent bad..but still functioned well..no leaks at all..coolant level was high..so what is that ice stuff you said? is it super coolant or something?..and the guy who owned the bike said he put a rear sprocket with 4 less teeth..not too sure if he knows what he was talking about though..he said he couldnt remeber..but it was to make the bike more "trail freindly"..which i heard about making the rear sprocket larger..for more torque..thanx again-josh

and the guy who owned the bike said he put a rear sprocket with 4 less teeth..not too sure if he knows what he was talking about though..he said he couldnt remeber..but it was to make the bike more "trail freindly"..which i heard about making the rear sprocket larger..for more torque..thanx again-josh

Yes... you want to add to the rear sprocket or remove from the front to lower the gearing. Removing 1 from the front is like adding 3 to the rear. Gearing down will (aside from lowereing the gearing) bring the gears closer together(giving better gear overlap), and help with the big gap between 1 and 2, and give the engine more mechanical advantage which will put more power to the dirt.

The benifit is being able to run a higher gear in the tight stuff, ride more in the torque than the HP and shift less. The trade-off is a lower top speed and more shifting in the really fast stuff.

awesome! i'll chek the sprockets and compare them to stock size and see how they differ...hopefully they are more trail ready..if not..i'll just deal with it..thanx again-josh

i have read that it is bad for your chain to use a 12 tooth sprocket. But that is the next size down on my bike. i find myself in first gear ALOT so i would like to change it up. it is the stock gearing 13/52. what do you recemend i go to. also it a 2001 cr 125!

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