hotcam exhaust cam mod

[cr 250]

hi i have a 01 yz 250f with manual decompression, easy to start cold, a pain when hot

I've heard of this hot cam thing, could someone explain it

will putting in a say oem 03 exhaust cam be better

what will happen to the decompression shaft on my engine where the decom cable links up to the exhaust cam, will their be a big hole in the front of my engine

[dustin63933]

After you put the hotcams in it I would just remove the lever and the wire completely. It'll be useless anyway.

How this camshaft works is where the camshaft sprocket is there's a piece that connects to a ball shipped pin that's centerd right where the exhaust valve is. At low RPMS this pin hits the valves and opens it just enough so it's way easier to start. (I can start mine by hand very easily)

As the revs pick up, a piece near the sprockets withdraws the pin from hitting the valves with centrifugal force. You don't have to worry about setting anything with the camshaft. It's a bolt on aftermarket.

[zuch95701]

Also i would like tp point out, if your bike starts great when its cold but no so well when it is hot you could have A) a jetting issue or ? piston, ring or cylinder wear. When the bike gets hot you start to loose compression, thus hard starting.

[cr 250]

well heres the thing

it doesnt like start to start hot after being stalled, if you just press the kill switch it will start pretty easily

but the bike is not jetted properly and lately its been unussauly hot, and i think the valves are out, so i'am doing that this weekend

so with the 03 OEM cam or hotcam, all i have to do is take out the cam and put the other cam back in its place, i dont need to touch the cam sprockets do i

[zuch95701]

the hot cam will come with a new sproket. You will want to change your timing chain if you open up the valve train.

[cr 250]

yeah i probably will, so i need a fly puller

are they expensive

[zuch95701]

No you can get a motion pro flywheel puller for around 25 bucks. I would buy one to have one because they fit many bikes and are a great tool to have.