2007 YZ450; No oil on dipstick

Just took another look at her. After I run the bike, there's oil on the dipstick, I assume its from oil entering and moving around in the tank. But when I wipe it off and stick it back in, nothing.

So, It seems oil is moving in the tank while it runs, but once the bike is shut off the oil level is not holding in the tank. I think the next thing I'm going to look at is pulling the balancer cover and looking for the hole in the casting that gray was talking about. Shouldn't be too big a deal to pull the cover I don't think?

it may have simply been the quart you added wasnt full. I would just add more oil till the level was correct dont put the cap on the resevoir just put a rag on top of it. this way there wont be a pressure problem if you overfill. im betting you just had a short quart

I just wanted to update this, I hate when I come across these threads with no solution, so....

Evidently it was "operator error". I added about 8oz. of oil to it, and everything seems to be fine now. I have no idea where that 8oz. went, like I said, the oil level was perfect immediately after I changed it, 2 rides later and it's not even showing on the dipstick. I'm thinking maybe I laid it over strange once and caused it to blow some oil out of the breather or something?

Before I added oil, I did remove the flywheel/stator cover to look for the hole Gray mentioned and everything in there looked great.

I guess I'll just have to keep an eye on it. Maybe the overheating was a product of the way I was riding, or the weather that day, I don't know. Like I said, I guess I'll just keep an eye on it. I really don't see anything catastrophic happening inside the engine to cause it.

Thank you everyone for your input, sorry I was so stubborn about the ammount of oil in it. I still can't believe it was just 8oz. low. Hopefully she's got a lot more fun left in her!

I'm curious about this particular problem, and I'm gathering info about it whenever I hear of it or see it, so I will ask, what oil do you use?



The thing I find curious is that you are using what I consider to be one of the two best available oils on the market, and change it at realistic intervals, yet you have found binding links in your cam chain.  I use either MCF (or MCV in the really hot weather), or Mobil1 Racing 4T (V-Twin in the hot weather months), and have no such trouble.  I do replace the cam chain about every 18 months because it's just good maintenance, as you pointed out.  I was doing them annually, but I stopped when it became obvious it wasn't needed; none of the chains I was removing had worn appreciably, nor did any of them have any stiff links.  I had thought this was oil related because I found the same thing on both bikes, but kept running into kinked chains on other engines where the owner's maintenance regimen was suspect.


So...apparently not.



I wonder if any of it relates to the difference in how the engine is used between Vet A MX and old guys racing desert scrambles and such.  I'm not going to suggest that it's easier on the engine, exactly, because, well, you should take a nearly stock-geared YZ450 on a flat out run across 1/3 mile of lake bed once (with a running start).  You'll understand.  But still, there's a lot of the 2 hours I spend on the race course that's not like that, too.


I have been considering replacing my piston recently, and remembered something mentioned about it in this post. So I was reading back through this and saw where you guys brought up the timing chain issue. Shortly after I created this thread, maybe a couple months, I was out riding and the timing chain skipped a tooth or two. When I pulled the chain, it was very sticky and kinked almost all the way through. I ordered a new chain that felt 100x better and installed it. Bike was back to running like a champ. It's only ever had Mobil1 4t oil, and as I stated, I ride recreationally, and only a few times a year. Just thought I would add that since it was brought up here.

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