THE HIT !?!?!

leak circuit? you mean the leak jet for the AP?

I'm going to wait on the cdi results before I mess with cam timing. But I am curious to see if they messed with the exhaust cams timing or not that for sure.

Right the leak jet. You could go smaller on that now. The older models didnt have that.

I'm curious about the cdi change. i've been thinking about getting an '03 cdi for my '04. if the '03 was the most potent of the 450's then each year becoming more mellow, sounds like the '03 cdi box would be the one to get if you wanted the most punch.

I can't feel any hit at all on my '04... The power delivery seems very linear and smooth from the bottom all the way to the top.

That's exactly what I thought the first time I rode one, too. I think the problem for a lot of people is that half throttle at 3500 does too much for them, and they haven't or can't learn how to manage the throttle. A long time two stroke rider, used to having 10 horsepower at that speed might have problem with having 30 instead. I think that the lower the power comes in, the more usable it is, even in large quantities, but a lot of guys can't deal with it, I guess.

Either way, it is one of the objections I hear a lot, and it was a concern that even I had before actually trying one out. So I can see it putting a dent in sales, and sales are where it's at for The Company.

I like the '05, I like how light it feels. The hit is still there you just have to ride it different than the previous 450's. I like it better.

ahhh sooo. The 250's always had it, so I assumed incorrectly it was always on the 450's too. interesting to know that it's new for them.

You should try advancing your cams ...

If you advance the cams by puttting them in one tooth advanced from spec, be very careful to check your valve to piston clearance before you start it up. Each tooth is worth 22.5 crankshaft degrees, and between the compression ratio and the agressive grind of the cam, I doubt you have that much room. Three intake valves will be over $210.

Besides, that's a very long way to move a camshaft. Typically, such adjustments would be made in amounts of less than 10 degrees (crank) by means of offset keys, etc. But, since Yamaha cam gears are pressed in place, this option isn't available.

hey yz250frider i just thought of a idea. i dont no if you thought of this but what if you get a lighter flywheel. i mean i hear people putting a heavier FW to mellow it out but why no just get a little lighter one to give it snap.

just a thought.

good thought thumperkid. It is on the list of options. The big trade off with it is the tendency to stall at low speeds.

you gotta be careful with that one though. It could easily turn into a rideabilty issue rather than just a performance one. Because of that it will probably be on the end of the list, but it's on there. :cry:

My sentiments exactly. Imagine my dismay after throwing down 7 big ones on a bike that no longer lives up to it's legend. Even after putting a 13T gear on the front, I still dont have to grab the bike with my knees. And I have yet to see it even come close to looping me. And popping my arms out of their sockets? LOL I have to pop the clutch on it coming out of the corners.

What I suggest you do is to work out your gearing properly for the track you ride...

The longest straight should see it just coming onto the rev limiter in top gear... you ain't going to go any faster than that point anywhere else on the trsck, so gear for that maximum point, and then the other ratios will follow suit... it will rev up quicker, accelerate quicker, and generally feel more like you wish with the gearing adjusted to suit the track...

Let us know how you go...


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