Topic: When would you use this type exhaust gasket (not copper crush)? Not solved

[VTCBike750]

http://www.z1enterprises.com/Exhaust-Gasket-Honda-CB750-VT750-CB900-CBR929-1598.aspx

[crazypj]

They work fine for Yamaha 

[TerryK]

I've been using them for many years on my Z1 Kawasaki. Never had a problem.

[seanbarney41]

are they re-usable or something?...if so, use 'em   if not, what's wrong with copper?

[Bodi]

There are several types of exhaust header gasket, in my experience they all work OK. There are ancient ones that look like your picture that are filled with asbestos, and I throw them out: but I only see those nowadays in flea market old-stock aftermarket gasket sets. The new ones are filled with some non-carcinogenic asbestos alternative.

[VTCBike750]

are they re-usable or something?...if so, use 'em   if not, what's wrong with copper?

Nothings wrong with the copper ones.  Im having a PITA issue with a reoccurring exhaust leak #1 exhaust and saw these online. 

On a side note these don't crush, and was what I was using when some of my exhaust bolt holes got stripped

[KingCustomCycles.com]

I would avoid the copper ones for corrosion problems they create..............Joke from another thread, proceed......

[VTCBike750]

I would avoid the copper ones for corrosion problems they create..............Joke from another thread, proceed......

Haha, read that one.  I cant tell if my anti-sieze has copper or not, says nothing, Im doomed.

[crazypj]

They do compress, but not as much as the copper ones.
 You may find they work better than stock as you have a bit more thickness before clamps bottom out

[VTCBike750]

So may give them a shot since I keep getting exhaust leaks?

Are these steel gaskets or made from something else?

[crazypj]

The older design was steel/asbestos, don't know whats in the new ones (asbestos was banned in US around 1980 something)

[Jeff.Saunders]

With some of the 4-1 pipes on the market, the lip on the header pipes where it does into the head is too thin.  V&H are notorious about skimping on this.  The consequence is standard gaskets aren't always thick enough to fill the gap.  These fiber version are a little thicker than the copper version.

The flip side of this - if you are still using stock pipes, stay with copper - otherwise it makes it difficult to the the exhaust flange nut started on the stud.

[millerza]

The older design was steel/asbestos, don't know whats in the new ones (asbestos was banned in US around 1980 something)

Asbestos is still used in some industries. Oil and Gas particularly. I work in a natural gas power plant and we use asbestos almost exclusively, except some applications. It is a superior gasket, the fryability(ability to become airborne) is low so there is little risk(still some risk though). Off subject but FYI

[VTCBike750]

So these gaskets are better? Anyone know if a place I can find more info on these?

[Jeff.Saunders]

are they re-usable or something?...if so, use 'em   if not, what's wrong with copper?

Nothings wrong with the copper ones.  Im having a PITA issue with a reoccurring exhaust leak #1 exhaust and saw these online. 

On a side note these don't crush, and was what I was using when some of my exhaust bolt holes got stripped

What pipe(s) are you running?  A 4-1 or the original factory pipes?

Make sure you have removed the old gaskets from the exhaust ports...  you may not realize an old one is crusted in there.

When you tighten up the nuts on the studs, is there any clearance between the exhaust flange and the head - you should visibly see a gap.  If the flange is bottoming out on the head, then these thicker exhasut gaskets will help you.

Check the lip on the header pipes - if there's damage to these, you may have issues getting the copper crush gaskets to compensate.

[VTCBike750]

What pipe(s) are you running?  A 4-1 or the original factory pipes?

So Ive had this reoccuring leak on #1, 2 sets of gaskets in 250 miles.
Ive had this other topic going as well:
http://forums.sohc4.net/index.php?topic=94787.0

Im running a 72 750 but learned that it has a F model collector that bolts up differently than the early K models.


There is talk ok the heads being different and the 72 being too deep to use copper gaskets?

I am also in the process of switching over to studs now. Getting rid of the bolts.

When you tighten up the nuts on the studs, is there any clearance between the exhaust flange and the head - you should visibly see a gap.  If the flange is bottoming out on the head, then these thicker exhasut gaskets will help you.

Check the lip on the header pipes - if there's damage to these, you may have issues getting the copper crush gaskets to compensate.

So the flange is DEFINETELY bottoming out.  No clearance at all. Before I just put them on and bolted them up, always bottoming out while crushing the copper gaskets. Basically need thicker gaskets. I tossed 2 old ones in just to get it to a buddy's garage before the hurricane.

I know for a fact Im getting the old gaskets out, cleaned the ports with acetone after the last leak. No damage to the lip on the header pipe.

Im thinking, If I use this gasket problems may be solved??

[VTCBike750]

With some of the 4-1 pipes on the market, the lip on the header pipes where it does into the head is too thin.  V&H are notorious about skimping on this.  The consequence is standard gaskets aren't always thick enough to fill the gap.  These fiber version are a little thicker than the copper version.

The flip side of this - if you are still using stock pipes, stay with copper - otherwise it makes it difficult to the the exhaust flange nut started on the stud.

AWESOME!!!

[bollingball]

Looks like the bolts are your problem. They could be to long and bottoming out and not crushing the gasket good enough. How flat was the one you took out? I would change to the correct length stud and nut.

[goaarongo]

I definitely prefer the fiber exhaust gaskets, but have had a hard time sourcing them lately.  Some of the websites even have a picture of them for the 750s, but when I order I get the copper ones.  I have used two sets of the copper gaskets at the same time to fix a persistent leak and that worked OK, but if you can find the fiber gaskets they are a superior product in my opinion.   

[VTCBike750]

Looks like the bolts are your problem. They could be to long and bottoming out and not crushing the gasket good enough. How flat was the one you took out? I would change to the correct length stud and nut.

I wish it was that easy.  Flanges are bottoming out against the head

[VTCBike750]

I definitely prefer the fiber exhaust gaskets, but have had a hard time sourcing them lately.  Some of the websites even have a picture of them for the 750s, but when I order I get the copper ones.  I have used two sets of the copper gaskets at the same time to fix a persistent leak and that worked OK, but if you can find the fiber gaskets they are a superior product in my opinion.   

http://www.cb750supply.com/products/4/engine

http://www.vintagecb750.com/products/4/engine

http://www.z1enterprises.com/catalog.aspx?pid=CB750K2-1972-EX0

Ever had any bad luck with any of these guys?

[Jeff.Saunders]

I checked our stock, and we are now receiving the copper versions as well.