leaky exhaust flange, best fix?

[Firecat400EX]

hey i just picked up a 86 250R with a 310 kit and it already has a billet exhaust flange (not sure on brand) with a new gasket and it leaks pretty bad. so i pulled it off and tried to seal it with 1200 degree gasket maker and that hasnt worked either

are there any other billet exhaust flanges that people have really good luck with? ive heard the ESR is one of the best?... or what else can i try?

[RichM1983]

Your always going to have leaks from your exhaust flange. I put a brand new pipe and flange and the seeling ring on the flange and mine still leaks. Its just something to get used to.

[Firecat400EX]

i know its common for it to leak a small amount, but mine spits oil out onto the case and on my leak. its not just a little leak. and i cant seem to fix it

[Firecat400EX]

oops i meant to say oil on my leg. not my leak haha

[bushwesl]

I used permatex high temp rtv silicone on mine and haven't really had any problems. Make sure you use a good amount and apply to both surfaces that you're mating together. You should let it cure for 24 hours before starting your engine too.

[250r4life]

i had good luck with the duncan dual o-ringed flange... and you can add a little silicone too if you wanted some added protection...

[Firecat400EX]

Originally posted by bushwesl
I used permatex high temp rtv silicone on mine and haven't really had any problems. Make sure you use a good amount and apply to both surfaces that you're mating together. You should let it cure for 24 hours before starting your engine too.

i tried exactly that (the copper colored stuff?) i beleive its the 1200 degree stuff, not sure. ill have to check that duncan flange o-ring.

anyone have good luck with certain other flanges?

[brokenmike]

I use permatex ultra black and that stuff works wonders. bI got no leaks on a stock flange!!!

[Live2Ride300]

I've always used the orange high temp RTV with great results.

[C-LEIGH RACING]

Reguardless of what you use, be it a new flange or any type of sealant on the market, over time it will start leaking again.

A 2 stroke pipe has to have some movement for it to function properly, thats why they are mounted together with springs.
The Permatex high temp sealant is as good as you can get for sealing it up.

The real problem all together, is the carb jetting its to rich for the type of riding your doing.
When a 2 stroke is jetted overly rich it trends not to burn or use all the fuel that is entering the engine.
A problem with in that, lets say you jet the carb down some, so it wont leak as much & ride as you normally do, but then somebody wants to ride it that will ride one real hard, just like racing, then the carb may not be rich enough for their riding style & end up locking your engine up because the jetting was so lean.

Its better to have the engine rich like it is & deal with the leak ever so often pulling the pipe & re-sealing it.

A little trick you might could try.
Get a small piece of the header exhaust wrap & one of those small narrow hose clamps. Take the header wrap & wrap it around the end of the pipe close as you can get it to the exhaust flange mount next to the bolts & then take the clamp & clamp it round the wrap & pipe to hold it in place.
After that, once the pipe leaks some the goo will collect behind the wrap, get kinda hard & after awhile seal the area on its own.
Neil