2010 Problem (cam cover leak)

Just wanted to bring this back up.Has anyone had their replacement valve cover gasket leak?So far so good on mine(knock on wood).

I have had the same problem now twice. The first time was after just about 15 hours. I had taken the bike in and had a power commander added so I thought maybe when then were testing and tuning that they might have caught the spark plug cap on the gasket. However, now I have had this happen again after just another 20 hours on the new gasket. I have ordered the part again from Yamaha who claims this not a common problem, but I can see from this forum it is.

Pardon the moderator while he himself hijacks the thread, but what made you decide to install a Power Commander on a '10 when it has a system for tuning the unit built in?

Mine just went, 8 hours on the bike. Split in the same spot as the others have mentioned.

Pardon the moderator while he himself hijacks the thread, but what made you decide to install a Power Commander on a '10 when it has a system for tuning the unit built in?
It was offered to him for free if he allowed them the use of his bike for a couple of days for testing. He only had to provide the FMF silencer and everything else was free. They actually put his bike on a Dyno and tuned for maximum horsepower!

Hope I didn't steal your thunder Rob!

Mine hasn´t split yet, but mine has barely been ridden. Wonder if I should pull it apart and have a look to see what it might be. Just an uneducated guess. but.... it couldnt be heat from the spark plug could it??? wrong gasket material??? from the pictures looks like it may have started distorting from the spark plug hole side. In my experiences squashed rubber gaskets leak almost strait away. Not after hours and hours of use. In the pictures, it is only distorted on the thin sides of the gasket. How hot have you guys been running these bikes?? Is it torn or melted??

Edited by Skotten

My guess it would be melted. I have only have about 2 hours and 20 mins on mine but am watching for oil to come through the hole.

ive got 2.06 hours on mine according to the tuner. and no leaking yet. anyone find a solution?

I've seen this sort of problem before. Trust me, it's not heat.

So far the only solution is buy a new one and make sure you torque it correctly.

As I stated earlier, torque won't affect it unless something is made wrong. Try this: leave the gasket out, and bolt the cover down, torquing it to spec. Now, notice that the cover is loose on the head, that there is a gap under it? That's the space supposed to be occupied by the compressed gasket. Whatever the reason, the space is too small.

I called Yamaha customer service Japan, and the lady on the phone know nothing about it. will let my dealer know what's going on later.

I don't really care to make it a big deal though. if my new gasket solves the problem, I'm ok. I just wanna fix it and go ride again. Parts recall on dirtbike always happens in US first, and then comes back to Japan, like a Y-pipe recall on 06? CRF250.

meantime, here is what my gasket looks like.


a rip around plug hole







New gasket


Looks the same as what I have on my bike. so I might have the same problem again....:banana:


Back side.

Is it possible that where the breather tube hose spigot is positioned in the valve cover doesn't allow the pressure to escape suffeciently due to the bridge seperating the two sides? A reliable mechanic told me that this was the cause and that the bridge that doesn't have the gasket over it needs to be hogged out to allow the pressure to escape.

That bridge is the baffling that the '98-'09 models never had. Without seeing how crankcase air is supposed to work through from the cam box to the outlet, I can't say for sure if it's unduly restrictive. If you feel a good strong pulse from the draft tube at idle, I'd say he was off the mark.

Also, note that the gasket is squeezed from the plug hole toward the cam box in the set of pictures shown. If excess pressure in the cam box were the culprit, you'd think it would go the other way.

Just curious, could we have;

1. State or country, of purchase of the problem bikes?

2. Air temps?

3. Type of use e.g. hard, intermediate, trail, desert ect?

4. Engine map?

5. Fuel type?

6. New oil type?

7. Hours of engine running time?

Just curious

Any more info on the cam cover gasket.

What do you want to know?Basically some of them leak.For whatever reason some of them start leaking.So far there is no reports of replaced ones leaking.

So far I have 4 hours logged on mine and I have been watching for a leak but havnt seen one yet (knock on wood)

I got 3 something, no leak yet.. I did break off the oil filter bolt though....

What do you want to know?Basically some of them leak.For whatever reason some of them start leaking.So far there is no reports of replaced ones leaking.

Just wondered if more bikes leaked, or if it was just a few.. Good that fixed ones still dont leak.

Ive got another 25 hours or so on mine after I fixed it and its not leaking still so I am not sure if they changed the part or what.

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