Hi, all.

I just finished replacing my front head cover gasket after 'popping' out a couple of the tabs while in stop and go traffic. The bike was at normal operating temperature. When it happened, I heard a couple 'pffft' sounds, followed by a small cloud of smoke coming from the engine. After inspecting the bike, I noticed the problem with the front gasket, and replaced it (kind of a PITA, but oh well). Today I got the fairing back on, washed of the excess oil from the previous incident, and went for a 30 mile ride involving highway, stop and go, etc. I stopped a few times to check out the new gasket, and everything looked good, except I noticed a little bit of smoke coming from the engine again. Finally I noticed the rear head cover gasket looks to have 'popped' out like the front had. I think this probably happened during the first incident along with front. Also, the last 3 miles of the ride my speedo cut out. The odometer still displayed, but no longer accumulated miles. The tach still works fine. Hmmm...

Mostly what I am concerned about are the gaskets. Is it typical for both to go at once? Am I seeing the symptoms of a larger problem? Hopefully the rear gasket isn't as much of a pain as the front...

-Jason

 

better check you valve cover crankcase breather hoses and that the sub-air filters they feed the airbox thru are not plugged. excessive crankcase pressure not venting thru the breathers can "pop" the gaskets and/or associated rubber cam end plugs.

 

yup... there is some sort of blockage somewhere.

 

Sounds like you had fuel vapors in your crankcase.

Have you modded your air box?

 

Did you put sealant on the semi-circular cut-outs before you put the cylinder head covers on? I found out the hard way that the semi-circular sections of the cylinder head cover gaskets will pop out if you don't.

 

Looks like I need to search for a blockage. Unfortunately I'll be gone for a week before I can take a look. Searching around here before I fixed the front had me thinking there were fuel vapors in the crank case as well. Air box is not modified. I did put sealant on the semicircular cut outs when I replaced the front gasket. Haven't had a chance to look at the rear gasket, but it looks pretty clean. Maybe PO didn't put sealant on that one?

Thanks for the help, guys!

 

The rear is easier to get to than the front.

Also are you on the stock R/R still? If so, I'd test that for your speedo / odometer issue as it is one of the two known weak points of the bike. (the other being CCTs)

 

How do you go about testing the R/R? As far as I can tell it is the original. Bike has ~33k miles. I've put on the last 7k with minimal issues. I'm sure the CCT replacement is within the scope of my mechanical abilities, but does anyone have an idea of how much labor is involved for a shop? If it is really only a couple hours for a qualified mechanic, I'd just as soon save the headache.

Thanks,
Jason

 

Replaced rear head cover gasket. Disabled PAIR (flipped reed valves) while I was at it. I believe I found the culprit breather hose. The hose had a nice big kink close to where it attaches to the tank. Hopefully that solves the gasket popping issue.