07 Yz 450

Alright so I just broke down and sold my 250 for a 450 - fourstroke! I really havn't had a chance to really get to know the bike all that well just yet but I broke it down and I'm getting all the mods done now...

I'm getting some suspension work through PR2 and my pops bought me a Ti4-GP exhaust system. Any ideas on the jetting?

I just did the exact same thing. This is my first four stroke (07 450) after racing 2 strokes forever and I love it. I just got my suspension back from pr2 today and will be racing it at budds creek this weekend. also put a 50t sprocket in the back, boyesen quickshot and gytr fuel screw. Cant wait to see how the suspension is.

Leave the Jetting alone. It will be near spot on pending conditions.

Hold on!! The thing is awesome! Suepension/motor/chassis is great.

wow - thanks a million! that was exactly the info I needed - I hope I get to roost all of you soon - and of course I never mind when the favor is returned!

RE: Jetting: I don't think you can really use the '06 specs. Different specs for the '07 motor. Stock jets are bigger in the pilot and smaller main compared to 2006.

My 2007 tends to stall easily in tight corners and is hard to start. I'm going to try going from 45 to 48 pilot first. I'll see about the main jet after (1 step at a time I remind myself!).

Or, I'll see what James Dean has. His kit worked wonders on my crf450.

BTW, I'm at sea level to 4,000 ft in SoCal.

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