Do you think my YZ is dead?

I would be such a shame as I have only had it for 6 months.

I went riding in the desert today and my YZ stopped. Lost power and stopped while climbing a dune.. :bonk:

Tried to restart it.. It popped once or twice but nothing. I thought it was the spark plug but when I loaded it on the truck, oil was coming out from underneath.. looked underneath and the oil drain plug was missing... aaaaggghhhh.. :cry: Must have worked its way loose but how.. :applause:

Friday is like a Sunday here so I can't even get a new drain plug.

Do you think there is even the slightest hope the bike still lives?

No steel to mention in the oil filter. Well at least not much more than usual..

But there is also no oil in the bike. Not in the engine, not in the frame..

Do you think I am up for a rebuild?

Going to replace the drain plug and fill with oil and try to start and run some more oil through it.. Or should I just take it in and have the mechanics here open it up. I am not really confident to open it up myself..

Oh man, I feel for ya. I experienced that Friday is Sunday thing for 2 months. Everything breaks on "the weekend". :applause:

I would guess you siezed the piston. At a minimum, you'll need a new piston and rings and maybe get by with a hone job on the cyl, but maybe a bore job would be required. I doubt fresh oil will help if it lost power and stopped like you say. Good news is that the bottom end and cams could be OK.

Anyway, read through this post, buy a small drill bit, and learn how to safety wire.

For the life of me I cannot figure out how running safety wire though the bolt head would keep the bolt in. Couldn't the bolt still work its way loose and just be dangling there by the safety wire with oil pouring out next to it?

Sorry to hear about the bike Berg.

Pincushion, look at the pic here:

its not a clear shot, just something i found w/google... but in the pic you can see how you wire it up from the drain bolt to the frame or another bolt or whatever. You are right, just putting safety wire on the drain bolt itself would be pointless.

Note how the wire is such that it will not allow the bolt to turn to the left - lefty loosey :applause:


I see..... the tension will not allow the bolt to turn. The key then is to keep the wire tight.

Thanks for the pic. Makes perfect sense now.

Thanks for the condolences and for the idea on the safety wire..

I am not sure about the siezed thing. The engine will turnover. I was trying to kickstart it and it felt the same as normal. Really I had nothing to indicate that it was out of oil until I saw that the bolt was missing..

Well I am going to get the drain bolt tomorrow.

Supposing the cylinder and piston are damaged. Do I risk damaging the top end and crank if I were to try to get it started? Coz if I have nothing to lose then I would try and do that in the hopes that it is not really seized..

Is it possible it could run for a few seconds without oil and not seize.. Sorry for the lamebrain questions they are the fading hopes of a Thumper lover...

Ooh yeah by the way thanks for the links to the big bore kits. Worst comes to worst I will definitely be looking at those that is if the OEM replacement is not dirt cheap...

It doesnt realy have to be super tight, just enough to keep the bolt from coming loose, but yeah thats it. Glad that helped :applause:


pull the head and jug and inspect it. I would not even consider starting the motor until I had thoroughly inpected the head, jug, piston & crank. If you run the bike again and seize the piston it will cause unnecessary stress on the rod and crank bearings, if they fail it is a guaranteed pain in the ass expensive job. An ounce of maintence is worth a pound of cure..........

So sorry to hear Berg, life is a bitch. :applause:

I was riding two years ago with my bud on a motocross track and his bike (my old 426) suddenly stopped on a straight and we noticed the same, drain plug was missing. It appeared he had forgotten to tighten it as he later recalled.

He ended up replacing all top end except the head with valves. Cams, piston, cylinder and oil pump gears. Just to be on safe side, he simultaneously also replaced crank bearings so he had the whole engine apart. It was like 2000 EUR only for parts.


Thanks guys..

Off to the mechanics tomorrow..

Oil plug just vibrated out..?? Man, that sounds hard to believe..Must have not been tight to begin with..Next oil change..Ill do the wire thang anyway, just to be sure..

Mechanics called me.

yeah it is dead.

No compression.

Head comes off on the 26th.

But he says dealer here has plenty of part and should be ready before next weekend..

Lets see.. I hope so...

i was thinking of getting a big bore kit but the only way to do that is to order from the States. That is major hassle for me here. Need US address or they won't take credit card etc. etc. would be waiting at least 2 weeks and maybe a month or more..

But I would still consider it if as well as giving more power it gave more reliability than the OEM..

488 Ice Cube is said it is stronger than OEM 450 OEM kit..

Any comments?

i will definitely be doing the safety wire mod..

Oil plug just vibrated out..?? Man, that sounds hard to believe..Must have not been tight to begin with..Next oil change..Ill do the wire thang anyway, just to be sure..

Yeah i couldn't beleive it either. Expecially as it was on its 5th hour of work since the last oil change. I mean why did it wait 4.5 hours to work it's way out?

I even thought it might be sabatage but how. I rode it stright with no one touching it for an hour before it fell off.

One of the mysteries of life. But I just will live and learn..

The safety mod is happening..

I am going to drill a new bolt before I even get the bike back..

Oh BTW.. did I say Merry Christmas guys. And thanks for the help.. :applause:

On my sons brand new 05yz450 the drain bolt in the frame fell out!!

I was very lucky and happened to see a cloud of smoke coming from the bike,I chased him down and started looking and found the bolt was gone! When the bolt fell out the oil poured out of the frame and on to his pipe,that was the smoke I saw!!I put another bolt in it added about a half qt. of oil and everything was ok! :applause: Needless to say I had a talk with the dealer the next day!

It is my understanding the head and valves are the first to suffer from lack of oil.

This was the case of my 99.

Valve journals were trashed.

There is a guy in California that refurbs heads, and does a GREAT JOB.

I am definitely going to start using safety wire on my bike to prevent that from happening. Good luck with your bike & hope you get it worked out.

So I just spoke to the mechanic.

Piston and Cylinder are screwed.

No obvious damage to head or crank.

Says replacement of parts is only a 1 day job but Yamaha doesn't have the parts in and it takes 45 days to get here agghghghgh. :applause:

That is like 6 weeks and no riding... And this is our good season .. It is a bit too hot in summer to ride except in the very early morning..

So I thought of a big bore kit but Probikes is closed for 10 days for Christmas and would cost more than double the cost of the OEM parts..

So I am screwed. Back to riding the old Husaberg for 6 weeks. Ride it, repair it, ride repair (it is an old one)... Just like an Italian girlfreind. You ride you buy it something...

Or if I wanted to get really crazy, buy a new YZ and get them sell this one as soon as it is repaired... Or get a WR so I could ride at night in the summer. But you can bet either way, I'll be doing the safety wire thing...

It is my understanding the head and valves are the first to suffer from lack of oil.

This was the case of my 99.

Valve journals were trashed.

There is a guy in California that refurbs heads, and does a GREAT JOB.

So how would I know if the valve journals are gone.. Sending the head to Ca is outta the question I think...

Nice to hear you managed it with "fairly" minor damages. As I said earlier, head with valves should be good, even though my buddy changed also the cams which I don't think would have been necessary for him either, but he said he does not want to tear it apart once again just because he possibly overlooked something.

Put it together and ride one year and buy the 2007 WR with aluframe if you need the lights.

Hey, did they also check the oil pump? It's been running dry...

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