Cylinder Head Gasket....leaks....Why.
 

Got to throw this out there. I got my "Bird of Prey" all ready to go for the track. I've been taking it on the street to check its performance. Came across and few issues that need to be cleared up. But the one problem that irritated me the most was the small oil leak on the front cylinder where the cam shaft and cam chain is located on the thin wall between the cylinder head and the cylinder.

The cylinder head gasket was leaking very slightly. So I put out a distress call to Roger Ditchfield -- the guru of VTRs. Very happy to have him reply and he said there has been a problem with the cylinder head gaskets in this area. It has happened to him twice now and he said that the cylinder head gaskets have been too long on the shelf.
This is his response to my email.

(ME) Just one more thing, I bolted the cylinder head gasket down to all the specifications, but the front cylinder leaks oil from the cam shaft chain side for some reason

(Roger) This is becoming an increasingly common issue. It has happened to me on two occasions. I believe that the head gaskets themselves are the issue as they are pretty old stock now coming out of Japan. Before re-fitting a new head gasket check with a straight edge that the head is nor warped.

Anyway I am not going to do the Head Gasket yet, I will put up with the leak, just in case there are any more adjustments that need to be done. Once I have it running correctly....I'll have to rip open the front cylinder again.:(

That sucks. I'm headed to the track w/ my Hawk either sunday or monday. Hoping monday as it's on Summit main.A larger more free flowing circuit.

https://cimg0.ibsrv.net/gimg/www.sup...ab5638c4a5.png

What track will you be riding on?

Sunday would be Jefferson.
https://cimg3.ibsrv.net/gimg/www.sup...e9ada6919d.png

Never, ever put add on coatings on Multi Layer coated steel gaskets

But I use copper coat gasket adhesive on every DRZ400 head gasket in the motor builds I do.....thats a few dozen a year since 2010.. Not one head gasket failure. There are big bore (90mm stock, 94 or larger now) high compression (13:1) stroker builds.

Different motor of course, different sealing issue we had to solve (ours was a compression leakage issue, not oil) But just saying, the manufactures recommendation in this case is being ignored and it works.

COMETIC had a gasket for our motor when I checked a few years ago....but I don't see it in the catalog now.. I have reached out to me Rep and asked if they still offer it... If so, Id use that over old stock OEM

Hey Wolverine
The track I have been riding on is Palmer, MA. I like the track....not that I have been on a lot...Just two.:) The other one was Cub Motorsports in NH by Fishtail.
I am in the Intermediate group...and I love it. I think the clubs have closed down for the season, which gives me more time to get my "Bird of Prey" ready...hopefully with an RC 51 swing arm.
Talk to you later.

Eagle why not Loudon?

Hey Joe73,
I haven't tried Loudon yet. It was originally an oval track. And they added the motorcycle track to it later. People have talked about the transition between the oval and the addition being a little hairy. The people who have have done Palmer have mentioned this to me. I'd rather go to Palmer because it is close enough and there's fewer concerns about the lay of the track. Maybe someday I'll get to Loudon. Let me know if you go!
--Geoff

Hey Marquez,
Do you have any more information on the head gasket by COMETIC?
I need to replace this -- and the clutch -- on my Bird of Prey.
And obviously I'm going to need the engine cover right-side gasket. Any information is appreciated.
Thanks,
Geoff (Eagle)

Never heard back from the email I sent so I just called Tech... They do not have at this time a product for us...... Though I have put a bug in thier ear about making the gasket.

The more folks that send a parts request, the more likely they are to produce it

Folks in the US sales@cometic.com write in and ask for the head gasket
Folks outside the US orders@cometic.com same thing

Thanks for your help Marquez
I will just have to do it again with the factory head gasket. The leak seems to be getting worse, but I am moving forward with this "Bird".
Later....