Purchased a 2004 YFZ 450

[Bobatvracer]

My son and I race hare scrambles in Northern New York. We recently purchased a Yamaha 04 YFZ 450. The quad appears to be stock except for the exhaust. Not sure where to start, I want to build a completive quad that won’t completely break my wallet. I have considered removing the engine and having it inspected and refreshed prior racing the quad this season. I have considered keeping the engine stock except for a performance cam any recommendations?? Are there any issues with the 04 YFZ that I should lookout for?? Both my son and I stand about 6ft 3inches, about 230lbs. Not sure if weight would be a huge consideration when determining engine modifications? Any advice you can provide would be great. I just want to brainstorm alittle..Thanks Bob

[elkin6]

keep the stock cam if you do some looking there is no real benifit to change it just do the cam mod also do the zip tie mod and the clutch mod i just did the clutch to mine and it is a nice diff only other things would be full exhaust, jets and open box with all the mods done man i almost forgot dose it have the oil mod if not that should be first

[yfzrider690]

Oil mod should be the first thing that you do, it puts a squirter in so it lubes the crank better and also uses a higher volume oil pump, the 07 and up yfz's come with it already done. Check out yfzcentral.com, there is a ton of info on there. The first mods I would do is the FCI intake and a good exhaust, you will pick up about 6-8hp just by doing those two things and rejetting.

[2001400exrida]

is there anyway to tell from the outsdie if the oil mod has been done?

[lkrislong]

no you cant tell unless you pull the case cover. i have a case cover with the oil mod if anyone wants it $150

[2001400exrida]

not for 150 nobody wants it haha, u can get them cheaper than that on ebay.

hotcams will give you a little performance, but not much over stock. what you can do is the "cam mod" which takes the stock exhaust cam and retards it 1 tooth. it makes it just like the yz dirtbike.

i have stage 2 hotcams and they are faster than stock i'll tell you that, but the stock ones are just fine especially with a port polish job.

[lkrislong]

so you have stage 2 hotcams out of the yz450f? ive looked all over ebay cant find them cheaper then 150 but its all good

[lkrislong]

or you can send your case to j&t pruducts they are pros they will mill it out for you put the squirter in and ship it back for $200 + shipping they do really good work but your bike is down til you get it back ill send you mine once you get it ship your old one back

[2001400exrida]

Originally posted by lkrislong
so you have stage 2 hotcams out of the yz450f? ive looked all over ebay cant find them cheaper then 150 but its all good

yeah, i wouldn't get the hotcams though, i've heard the cam mod is better.

i do pull on my buddies at high revs though.