Hey all, I have a 450 foreman es that will not rev up. I have put a new carburetor, reset the valves and made sure the exhaust isn't clogged but it still acts like it is hitting a rev limiter, it just won't rev up. What could be my problem?

 

Dirty air filter? Sucking air somewhere?

 

Thanks for the relpy Bowtie_Life! A new air filter is also what I put in it. No I don't think it is sucking air, everything seems tight.

 

Hmm I womder if you need differ jetting or the fuel air screw isn't correct. Or the choke cable is stuck pulling it to choke the motor?

 

I live at about 600 ft above sea level, so I wouldn't think so. I messed with the air screw with the old carb and with the new one and it don't make any difference. That is something else I replaced was the choke cable. I really appreciate you taking the time to help me!

 

Yea not a problem the last thing I could think of is crank seals leaking sucking in air and lowering compression causing low revs

 

I f atv been sitting for an short time sometime dirtdopper or rat builds nest inside air snorkel...Try to run atv without air box lid to see if runs better if so look inside air snorkel for restrictions.... then get back with us here Thanks..

 

Thanks for the reply papa hogg scoot, it runs the same even with the whole air box off.

Bowtie_life, how would I check to see if it is the crank seals? When it is running it seems to be sucking or pushing out air down by the motor but it might just be my ears.
Thanks again.

 

There are a couple ways to test one do a leak down test where you can put pressure in the motor and see if it holds. Or you can remove recoil and what not so you can run the motor still but see the crank seals then with the motor running spray carb cleaner on the seals and see if it revs

 

Ok plz give us more information on atv....Did you trade or buy atv running like this? did you ride and atv then started doing this? Ran fine when parked and then started running like this when restarted up? Has someone else been working on atv before you got atv?