gs1100 base gasket

[rosco15]

I blew the paper base gasket out out on my bike. I want to use a copper gasket, but have always had trouble with them seeping oil. The paper didn't leak, but it also didn't stay in place. Then I had a big leak.

Does anyone know any tricks to get the copper base gasket to not leak. Or is anyone aware of a different gasket material that can be used instead of copper that is better than the stock paper?

Thanks,
Ryan

https://www.rccracing.com

[Dink]

I use loctite product #37559 it is non setting and allows some gaskets to be reused.
Dink

[Anonymous]

Was it the original paper base gasket or a replacement?

There should be very little pressure inside the cases to force the gastket out - at least with a motor that has minimal blow by and adequate venting. At least as I understand it. Any opinions?

[Anonymous]

There should be very little pressure inside the cases to force the gastket out - at least with a motor that has minimal blow by and adequate venting. At least as I understand it. Any opinions?

I have always seen that the reason for base gasket failure is movement between the upper case and cylinder block (like a fretting motion). It balls up the paper gaskets and destroys the seal. Supposedly. The copper gaskets do not fail from this motion, so they are used when performance is upped.


Mark

[Hap Call]

I've seen this also happen if the head/cylinder torque is not checked after an adequate break-in period.

Hap

[Anonymous]

Interesting - I'm using paper gaskets now on my rebuild. I guess I'll use them until I run into problems.

I do plan on retorquing the heads even though the directions for the head gaskets say you don't have to do that.

[Paul]

Interesting - I'm using paper gaskets now on my rebuild. I guess I'll use them until I run into problems.

I do plan on retorquing the heads even though the directions for the head gaskets say you don't have to do that.

That's exactly what I do.

I have never seen copper base gaskets, head gaskets yes, but not a base gasket. A copper gasket is used with higher compression because it is stronger, & so withstands the higher pressures. But a base gasket is only there to stop an oil leak - period.

[rosco15]

It pushed out on the outside on the right side. ignition side. I looked at the block and the cases and it seems there isn't very much meat between the oil galley in the block and the outside air. The paper gasket seems like it is pushed slightly up into the oil galley in the block. I did retorque it after racing it the first time. It was a cometic gasket. I think I will try copper and some gaskacinch. I think thats how you say it.

I wonder what they put in the newer bikes. I have an aluminum gasket with a foam over it for my valve cover gasket made by cometic. I guess they use it on the Harleys to fix the oil leaks. I'm not sure if soemthing like that would hold up to the movement mark described.

Ryan

[RacingJake]

Hi Ryan

When I pulled my 1075 block & pistons and installed the 1166 block & pistons I notice I was missng one dowel between the case and block that would allow you to move the block from side to side just alittle. I also removed some gasket material inside the oil passage way to prevent it from blocking the passage just in case. I now have about a 1/4 inch of gasket at the edge of the block around the oil passages. Will see if it leaks next month.

Jake

[rosco15]

Jake,

That caused me to go out to the garage. I'm thinking what is he talking about. Thinking of my KZ1000 I looked at the outside stud and didn't see any place to put a dowel. Then I looked at the rest of the studs.

well isnt that a *@%^$*@%^$*@%^$*@%^$er. I only have one dowel in mine as well. Looking at it I would say it deffinently should have 2. One on each side, second from the outside, on the front. Well if that didn't cause the oil leak i'm sure it didn't help. Hmm do I dare try paper again. Thanks,

[RacingJake]

I think i paid just a few bucks from the dealer to get one. When I installed the new one the block could'nt move anymore. I was thinking of using a copper gasket too or maybe a spacer one day to lower the compression. I'm keeping my finger's cross.

[Anonymous]

If you are blowing gaskets out you might want to check the hose coming from the cam cover to see if it is blocked off. If you have a breather on it already you might want to run the hose to the collector to try and create negative pressure in the crankcase.

[rosco15]

The hose run to a catch can now. When you say negative pressure do you mean like a vacume pump.

[Anonymous]

Yes, just like a vacume pump. It is used in auto racing a lot. I've even heard of vacume pumps being used.

[Anonymous]

Yes, just like a vacume pump. It is used in auto racing a lot. I've even heard of vacume pumps being used.

The current AMA ProStock bikes all run vacuum pumps to evacuate the cases. There was an article in Cycle World about 18 months ago on the bike that Angele Seeling took her first title on and the builder (I forget his name at the moment) used three pumps on the bike. He said they were running something like 20" of vacuum in the cases and picked up around 20hp doing it. That is on a 300+hp motor, so it was worth around 6% power increase to carry those pumps.

Mark