What breaks on '08 / '09 YZ450f's?

I've been riding Honda's for years now, but now is the time to try a Yamaha....

I'm NOT going for the 2010 model, so I'm getting a new leftover '08 or '09.

-What should I be aware of on these models?

-Anything that usually breaks/needs attention in particular?

-What's different from 08 to 09 models? (rear hub+swingarm I know, but what about transmission and engine?)

-What handlebar bend comes stock?

-Anything else to be aware of? (clutch fade, engine oil choice etc... ?)

Thanks :busted:

I rode my 08 for one year and I did not even need a valve adjust, still good. The Boysen quickshot 3 for the carb helped smooth out the carb burps..

Change the front tire, swap the exhaust.... oh wait, what breaks depends on how hard/often you ride/crash really. Keep up on oil changes and keep a clean air filter. Should be good for a while most likely. They do have a much better valve train reputation than Honda.

Nothing breaks. Get used to the fact that these bikes are reliable. Regular and proper maintenance and you won't have any problems. The front tire and stock chain are junk. Replace them, jet it and ride. If you want more power a pipe will wake the bike up significantly.

The only real difference is the swingarm and rear hub as you mentioned. Pretty much all other parts are interchangeable between the 08 and 09 (most are interchangeable between 06-09). The two things that are a problem are the stock chain and the stock silencer. The chain is junk and stretches like a rubber band, which in turn wipes out the sprockets. If you put a good chain on right away then the stock sprockets will last a lot longer. The stock silencer doesn't break or anything, but it is very restrictive (though it is pretty quiet). If noise isn't an issue and you are looking for more power, pretty much any slip on will give you pretty substantial power gains. Other than that these bikes are pretty much ready to go right out of the box.

Just to clarify on the power thing, there is no problem with the top end, peak power output of the '08/'09. The trouble is a soft mid range. But KJ is otherwise right about the exhaust, and nearly anything will bump the output by from 4-7 HP at around 5000-6000 rpm. Probably the most bang for the buck you'll get out of changing the exhaust on a dirt bike.

Ditch the stock chain immediately. Replace the exhaust (or at least the silencer) if you want more low/mid power. That's about it really.

Stay on top of the steering head bearings maintenance-wise. Yamaha improved the upper seal but water still tends to get in there fairly easily. Just regrease them regularly and its fine.

One other thing...coming from a Honda you need to realize that the YZ tranny and engine share the same oil so make sure to keep it fresh.

Thanks guys!, nice feedback. I'm a experienced rider so I'm used to all the regular stuff about chain, tires etc.

But how well do transmissions and clutches hold up on these bikes?

Seems like clutchpull is nice and easy on yzf's, but think I'll buy a asv lever/perch (sorry if my language fails a bit now and then), I've been happy with these on Honda's since the leverage ratio is less and there's a ball bearing on the pivot = easier pull.

My experience with yamaha's so far is limited, but I definetly feel they're more calm, balanced and confidenceinspiring than most other dirt bikes I've ridden. Hope that translates into speed :busted:

If you shift cleanly, the trans will hold up very well. If you tend to slop things up a little and clash gears, or force shifts without the clutch under heavy loads, you'll eventually round off the locking lugs on the gears, and the bike will begin "skipping" in gear. Takes a long time to develop.

The clutch will work fine as long as you ride it like a four-stroke. If you'd rather use the clutch as a substitute for shifting to the right gear, you can beat them up in under a season.

If you want to toughen the clutch up a little, you can convert it back to the 9 plate stack the '06 had in it. That requires changing a few parts besides the plates, and the pull is a little harder, but it's not too hard, nor is it very expensive.

Ditch the stock chain immediately.

... slightly resurrected thread from last month...

I thought Yamaha put a high quality DID chain on the 08/09s. Anyone have more info? Do I remember bad info?


It is said to be a better chain than in the past, but reports indicate it doesn't hold up particularly well, even so.

I just picked up an 09 yesterday and was pretty impressed coming from an 07. Forks worked good but I need to calm the shock a little. Yes the chain stretched a huge amount. I felt it had good enough low end little soft mid and the track I was on did'nt allow me to really rev it out to far.

It seemed to be jetted much cleaner than the previous yams I have owned.

I was really wanting the 10 but not for the price, I paid 5499 for the 09 so that saved about 3k.

O/A I'm really happy so far

I bought a new white 08 on Friday ($4280 otd) and from what little time i have on it the chain is the only thing im gonna change for now!! I wanted blue but they said i could get an 09 they had for 1k more,

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