Deep Doo Doo

I just bought a brand new 05' YZ450F and love it. I broke it in and did my first oil change at 2.9 hours, ( just after break in.) Everything's going great, ( accept for a little jetting issues, but thats the least of my worries.) I'm putting along in first gear on a tight trail ride at Stonyford CA when my bike just dies !!!!! It felt like the ignition just cut off ? So I check the fuel....... no not that. And thats when I notice a bunch of oil on my chain and left case. Wholly @%$#&. My oil drain plug just fell out, and most, if not all of my oil is decorating the trails, ( AND I KNOW I TIGHTENED THAT DRAIN PLUG.)

So the cylinder was not extremely hot, and the oil cap didn't have that "burnt" smell so I don't think I killed the motor, ( but I'm afraid to find out.) The bike kicked over with ease after the event.

So heres the question .......... Does Yamaha have a kill switch that prevents the motor to run with low or no oil pressure, and has anybody else had this happen to them ????????????

I got a new drain plug on order, and I have yet to try to start it. Don't worry, I'll fill it with oil first :naughty:

Wow, never heard of that before...

Breaking a bike in on a tight trail isnt the best idea bud. The bike needs plenty of fresh air passing through the radiator while breaking in as the motor is very tight and heats up quicker and a "run in" motor.

Will be interesting to find out if there is some sort of switch or warning device...


If your lucky, when you add new oil to the engine, the compression will come back and the bike will run again. Hopefully you still had enough oil left in the engine to keep the major parts lubricated. Do you figure that you had any oil left in there? If I were you, I would take the valve cover off and have a peak at the cams and all that. If they look like they have starved for oil, I would think about tearing the engine down and going over it.

If your plug was all the way out, and almost all of the oil fell out, i think you might have a problem. I don't think the yammie has a weak pressure cut out switch. Never heard of that.

i too would pop the cam cover, just for a look-see.

best of luck

Wow, never heard of that before...

Breaking a bike in on a tight trail isnt the best idea bud. The bike needs plenty of fresh air passing through the radiator while breaking in as the motor is very tight and heats up quicker and a "run in" motor.


think he mentioned it was run in.

Doesn't sound good. The 426 models did not have a low oil pressure shut off switch, and I'll bet $5 the 450's don't either. When a 4-stroke stops running due to lack of oil it's never good. It may fire if you put some oil in it, but that doesn't mean all is OK. Personally I would pull the cams and the cylinder and have a look. The only good thing is that you were going slow. Next question; did you use a torque wrench on the oil drain plugs? Sure lots of people don't, but I'll bet that more people who don't have lost drain plugs than those who do. Best of luck and let us know how it turns out!

I have never heard of any dirt bike having a low pressure switch, in fact I cant even think of any road bikes that do.

I have a 5 hp Briggs on a leaf shredder that has a low oil shut off, but my 450 hasn't got one.

If you're lucky, the bike just stalled on you because it didn't like going that slow. They're cranky like that. If so, it may have died before it hurt itself.

But you have to face something here. Whichever drain plug fell out, it was because it was not tightened properly. :naughty:

Time for a complete re-build. What oil did you use? If you used the same as the factory take it back for the 30 day warrenty.

I don't think anyone is going to cover damage caused by a drain plug falling out under warranty when the owner did the oil change. It's for defects of workmanship and materials, but it's limited to their workmanship.

but how would they ever know?

fill it back up with oil... clean up all the oiley mess from the bike... and then call them and tell them it seized up if that is the case or something along those lines... i am not trying to sound like a scammer but otherwise their warranty is only good for the break in period?? after you change the oil it is void?

it would be very obvious once the engine was opened up. worth a shot anyway i guess

Since when is there a 30 day warranty on a YZF450? :naughty:

Maybe your dealer will be cool but what are you going to say?

"my motor siezed can you rebuild it"?

" I forgot to tighten the drain plug - or you (dealer) forgot to tighten the drain plug"

I would fill it up with oil refire it and see how it runs - if it starts so much for the " it siezed" route

if it doesn't you have the other options....... :naughty:

There is not way they will warranty a bike that ran out of oil. Even if the bike gets new oil, once they open it up, they will definatly know (unless they are brain dead) At our shop, we have had a few customers try that one. The first thing they say is "gee, I dont know what happened" or "I didn't hear a thing" But the fact is we can always tell the real story once we open it up.

You mean the perfectly clean oil in a trashed engine is a giveaway? Who'd have thunk it?

Can you say "fraud" boys and girls?

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