New owner of a brand new 08 yz 450f!

not as quite as it is constrivctive to the motor.but yes quiet enough

wont a magnetic drain bolt be as usefull as the hole mod?

wont a magnetic drain bolt be as usefull as the hole mod?
No. A magnetic drain plug has no effect on the oil filter well.
No. A magnetic drain plug has no effect on the oil filter well.

but does it help at all?

It helps in general, yes, as it traps a certain amount of steel shed from the trans before it gets into the rest of the oiling system. But it doesn't have a noticeable effect on keeping the threads clean on the lower filter cover bolt. Remember that steel is not the only contaminant your oil will send to the filter, and magnets can only catch steel and iron.

I just bought it from a guy in Kentucky, he put a Yoshimura RS2 slip on exhaust on it and a 50T rear sprocket. I am at 500ft above sea level in Indiana. The bike is has 8 hours on it and runs great. It does have a slight bog when you twist the throttle really fast. It has stock jetting, do I need to rejet this bike? I ran a 165 main in it today and started it and it bogged bad off response, and also popped quite a bit. I rode it when I bought it on the street, and it picked up good. Only reason Im asking about the jetting is everywhere Im reading you have to rejet for the aftermarket exhaust.

I have it torn down to regrease all the linkage and swingarm pivots. They were dry and it was squeaking when I sat on it. The previous owner pressure washed it a few times, maybe blowing out what little grease was it in from the factory. Any help is appreciated!

It helps in general, yes, as it traps a certain amount of steel shed from the trans before it gets into the rest of the oiling system. But it doesn't have a noticeable effect on keeping the threads clean on the lower filter cover bolt. Remember that steel is not the only contaminant your oil will send to the filter, and magnets can only catch steel and iron.

thnks alot.

hey derek...dont have mine yet but ive read it pretty much has to be spot on jetting....im sure grey can answer that one....and im sure ill have my turn at jetting the 450:(

Yeah, I just want to be sure its okay. This is my first 4stroke, I just want it to run like my other bikes always have. Thanks in advance!

I also have a 08 yamaha 450 and live in sacramento. I went to a 48 pilot and then raised the clip one position and got rid of the bog!! I have tried the ac wire trick and run it without. Try this and you might like it! I run a stock main!!

I think if you were to use any of the 450 mx bikes for woods riding, the YZ is probably the best choice.

I dont ride woods, but i installed a Rekluse Pro clutch on mine before i had 5 hours on the bike. Once i learned how to ride with this clutch setup, it greatly reduced its tendency to stall in low speed throttle off corners

I put an aftermarket exhaust on mine, but if i was riding woods, i would likely leave the stocker on because its so quiet.

The chain is a must do within the first few hours as well, have fun with your new bike! hope the snow clears off soon

Greyracer what is your opinion on my jetting quest? The yosh slip on is the only mod on this bike.

If you ride offroad through creeks or anything I would re route your breather tube higher up so that if it stalls in the water it doesn't suck water up the tube while you are trying to start it.

So you have to jet these bikes specific to temperature? I thought that there was a baseline setting that would be recommended. Thanks for the link, even at same altitudes people were posting all sorts of changes. I think I will have to wait until the weather warms up here and see what the bike does and buy a jetting kit. I am thinking though, and these are my thoughts, that the slip on muffler on the bike should only require minor adjustment to the fuel screw and not jetting changes. Am I wrong here?

Thanks about the breather tube idea also, I was wondering what to do with that one!

So you have to jet these bikes specific to temperature? I thought that there was a baseline setting that would be recommended. Thanks for the link, even at same altitudes people were posting all sorts of changes. I think I will have to wait until the weather warms up here and see what the bike does and buy a jetting kit. I am thinking though, and these are my thoughts, that the slip on muffler on the bike should only require minor adjustment to the fuel screw and not jetting changes. Am I wrong here?
You are right about the muffler. But even though your bike should be able to run well with the same jetting across a pretty wide range of conditions, very cold weather does cause them to act lean.

Thanks for all the advise, I regreased all the linkage and swingarm, rear axle and steering head. I found little or no grease on any of these parts! The steering head bearings were wet from water being blasted on them and were starting to corrode. I cleaned everything up and it works much smoother now!

The stock chain forms a half moon when you bend it lying on the ground, its junk. I ordered a Renthal R1 Works chain and sprockets for it. Ive heard good things about them, I am going to an indoor track asap when the bike is all tight.

I just purchased a '08 450 also. Does anyone know the maximum amount that the forks can be raised (measuring from the top of the top triple clamp) on the '08 YZ450F before the bike becomes ill handling (or the tire rubs when bottoming). This is assuming the sag on the rear is set properly.

I don't mean to thread jack, but I am picking up my 08 soon and was wondering exactly where I should grease evrything before I ride. Anyone have a link? (please don't tell me to search, if I would have found something, I would not have posted! :-))

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