LCGB Forums

does anyone use these,,,,,and if so any particular way.....heated etc

Interested to know the answer to this.

have used solid copper exh gaskets since the 80s . i just heat them to cherry red and quench in water to anneal each time its removed ,refit with high temp exh sealant . biggest advantage in my opinion is they dont compress over time so your exh stays tight .still got the one i purchased from taffspeed in 85 with my stg 4.

paul213 wrote:have used solid copper exh gaskets since the 80s . i just heat them to cherry red and quench in water to anneal each time its removed ,refit with high temp exh sealant . biggest advantage in my opinion is they dont compress over time so your exh stays tight .still got the one i purchased from taffspeed in 85 with my stg 4.

Glad to hear that Paul reason i ask is that the regular big bore ones you buy now you cant file or cut them to make them larger because they are like soft sandwiched centre........and i need bigger so lucky i have two copper ones i never used before so they are ideal to file and shape.
thanks again.

Get the ones from Franspeed, thick n chunky and already annealed but both mating surfaces must be spot on

paul213 wrote:have used solid copper exh gaskets since the 80s . i just heat them to cherry red and quench in water to anneal each time its removed ,refit with high temp exh sealant . biggest advantage in my opinion is they dont compress over time so your exh stays tight .still got the one i purchased from taffspeed in 85 with my stg 4.

So you anneal it- cool it in water and then fit? do you need to warm it again when refitting? you have to excuse my ignorance with this I tried a couple of big bore copper gaskets in the past and just couldn't get them to seal very well so went back to the fibre based type. Paul

just heat to cherry red immediately quench in water (this leaves it in softened state) light rub on emery cloth or similar to remove any burn sealant apply new sealant and refit . As regards to a perfect seal is this possible on a lambretta ? i have never had an engine where the exhaust didn't weep slightly no matter how much time I spend flattening the stub though this has never proved a problem .

I only use solid copper gaskets. Here’s my method, which is successfully served me well (posted before, but worth repeating)

1 - good condition, high tensile exhaust studs
2 - studs loctite'd into the barrel
3 - solid copper annealed gasket - make sure all burrs are cleaned off the gasket before annealing and the gasket fits onto the studs without forcing it on. I've opened up the holes 0.5mm so the gasket slides into position without forcing it on.
4 - ensure the manifold on the exhaust is flat, and not bowed/distorted
5 - when ready to assemble, clean all faces with a degreaser to ensure good sealant bond
6 - use loctite copper sealant, allow to cure slightly for a short time (20 mins)
7 - assemble using new k-nuts
8 - Don't start the scooter until the next day allowing the sealant to completely cure

I use K-nuts instead of the usual lambretta brass nuts. Find them on eBay or Merlin Motorsport

very helpful, thanks for that.

Does anybody go gasketless?????is it possible to used a good enough exhaust paste?????

shamrockexpress wrote:Does anybody go gasketless?????is it possible to used a good enough exhaust paste?????

It be a brave man or woman to do that Damian

ULC Soulagent wrote:

shamrockexpress wrote:Does anybody go gasketless?????is it possible to used a good enough exhaust paste?????

It be a brave man or woman to do that Damian

Go ahead Shane stand up and be counted show us what youre made off!!!!!!!!!!!!!!!

I’ve a solid gasket that I never realised I had until yesterday. Found just in time to use on my current Gori build. I wasn’t aware of annealing the gasket.

I never used an exhaust gasket on my TS1 just Threebond. That was with a CST3 pipe. Passed the leak down test and never noticed any leaks after. I’ve not been able to do it since on any other set up.

shamrockexpress wrote:Does anybody go gasketless?????is it possible to used a good enough exhaust paste?????

If you do this you may find that the exhaust box doesn't line up nicely with the brackets fixing points because the manifold is now sitting about 3mm higher!

for what its worth - was toying with a solid gasket but pushed on a standard folded copper composite gasket on my recent build and could not seal it (without sealant) swapped to a fibre type (from AF) and sealed under mechanical means without sealant - I`m pleased with that and will just carry a spare

Mind time may tell.......

nsaints wrote:7 - assemble using new k-nuts

I use K-nuts instead of the usual lambretta brass nuts. Find them on eBay or Merlin Motorsport

1st time I have used K-nuts this time - didnt realise thats what they were called TBH.

I used solid copper ones which are from a BMW exhaust manifold - which are also M7. They are available on ebay.

Bit weird putting them on, as it feels like they are miss-threaded - but they are oval at the top - which is the locking action.

Fast n Furious wrote:

shamrockexpress wrote:Does anybody go gasketless?????is it possible to used a good enough exhaust paste?????

If you do this you may find that the exhaust box doesn't line up nicely with the brackets fixing points because the manifold is now sitting about 3mm higher!

I went with the solid copper gasket and three bond on the ex-box, will see how it holds out when the weather eases off

shamrockexpress wrote:

Fast n Furious wrote:

shamrockexpress wrote:Does anybody go gasketless?????is it possible to used a good enough exhaust paste?????

If you do this you may find that the exhaust box doesn't line up nicely with the brackets fixing points because the manifold is now sitting about 3mm higher!

I went with the solid copper gasket and three bond on the ex-box, will see how it holds out when the weather eases off

The gasket wear and studs coming loose is much less of an issue with the stub type exhausts. My Ex box is same solid gasket and hi temp silicone. Also I had to face the stub manifold in the lathe as it was quite a bit of being flat.

Had the BGM exhaust gaskets fail, they seem to blow through on one of the edges.