Looking at buying a 03 YZ450f... Pics and Video. Plz Comment

7 replies to this topic
  • osmondmark

Posted January 25, 2007 - 12:46 PM


Im looking at buying a 2003 Yz450f. I was just wondering if you could have a look at the following video and see what you think. Any comments or feedback please let me know. Thanks for the help.

Also is it normal for a very small amount of coolant to come out of the overflow hose?

Thanks again.

The video is

And the pics...
Posted Image

Posted Image

  • qkenuf4u

Posted January 25, 2007 - 03:57 PM


could be a bad cap or maybe head gasket is going (allowing compression into the water jacket/rads)

dont like that little flame i saw either. get in there and check those valve clearances, might be tight.

i just paid 3k for mine in motard trim and LOVE IT !!!

  • flintlock28

Posted January 25, 2007 - 04:07 PM


It is normal for the Yzf's to spit a little coolant, if the bike idles for more than 2 or 3 minutes or longer, since there's very little air moving through the radiator's. Also, if ridden on tight, slow trails, she can also begin to overheat. I use "Engine Ice", which is an aftermarket coolant replacement, to get rid of the boil-over.

Pro's: The 03' had the nastiest "hit" of all the YZf's...which some people love, and other's find too tiring on a MX track. The powerband was slightly detuned for 04', and some people claim the 05' model was toned down too much. The yzf's are also very reliable, with probably the most reliable valvetrain of the big 5 manufacturers.

The bike because of it's very light flywheel, and hard "hit" is more difficult to ride on tight trails (it will want to stall easy)...unless you add additional flywheel weight. The pre-06' models are top heavy, and like to stand up in the turns...this can be helped somewhat with changing the linkage out to a Stormlink aftermarket linkage. The 03' has the smallest diameter fork tubes of the 03'-07' models. Every year the forks got better.

Hope this helps.

It's still an awesome bike, and I love my 04' but If I could do it, I'd trade up to an 06' or 07' model..they handle much better.

  • osmondmark

Posted January 25, 2007 - 05:45 PM


I plan on checking the valves and adjusting them as required.

As for the coolant I have been told that its normal for a little bit. It comes out of the overflow. I was thinking that when it gets warm the coolant expands and some comes out.

As for the spark. What do you think it could be? Could it be that its cold here and the bike could be running lean? Or what else could it be?

Any more ideas or comments?

Thanks for the help.

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  • flintlock28

Posted January 25, 2007 - 08:14 PM


I noticed a couple of times that when it was getting near Sunset, and I whacked the throttle, I got a little spark outta my stock exhaust....I can't say that this is a problem, or normal, since these bikes don't come with spark arrestors.

Also, the Fuel screw has a big impact on being rich/lean from off idle to 1/3 of throttle or so...and with the cold weather, it's alot easier to run lean. Do a search on setting the fuel screw.

  • osmondmark

Posted January 26, 2007 - 07:58 AM


I plan on checking it over completely and adjusting what has to be. So I'm not worried as much about the little stuff. More so the big stuff. Ie. the engine. (crank bearing, etc.)

Also it is probley just me but does the front look to be sitting a little low? I'm not used to dirt bikes as much so please excuse me for the stupid questions.

  • 642MX

Posted January 26, 2007 - 09:37 AM


Looks good and sounds good to me. Spitting coolant and flames are normal. The 03 model was very fast, but I didn't like the 4 speed tranny.

  • osmondmark

Posted January 26, 2007 - 10:58 AM


Thats what I wanted to hear. Thanks a lot for the help!

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