KX Riders

Maintenance & Technical => KX500 Original => Topic started by: 91kawifive00 on October 11, 2011, 06:45:04 AM

Title: exhaust leak
Post by: 91kawifive00 on October 11, 2011, 06:45:04 AM
whats going on guys. i cant seem to stop the leak i have where the pipe meets the cylinder. its really noticable on a cold start. it seems to stop as the bike gets hot due to the metal swelling. i put new o-rings in and also tried chamber seal still no luck.. and help would be greatly appriciated. thanks
Title: Re: exhaust leak
Post by: Purpletj on October 11, 2011, 03:31:57 PM
I use black RTV sealant. Apply a genorous amount and let it dry over night. Has solved my problems. If this dont work then you may need to contact Larry.

http://www.kxriders.com/forums/index.php/topic,6254.0.html
Title: Re: exhaust leak
Post by: Polar-Bus on October 12, 2011, 12:52:04 AM
whats going on guys. i cant seem to stop the leak i have where the pipe meets the cylinder. its really noticable on a cold start. it seems to stop as the bike gets hot due to the metal swelling. i put new o-rings in and also tried chamber seal still no luck.. and help would be greatly appriciated. thanks

Thats a area that is prone to leakage. Excessive vibration hammers the piss out of the sealing o-rings and crush gasket. get a set of fresh o-rings, use TWO crush gaskets, and smear some high temp RTV around the od of the pipe. No more spooge leakage.
Title: Re: exhaust leak
Post by: 91kawifive00 on October 12, 2011, 01:13:13 AM
awesome :-) i think i got some high temp rtv in the tool box. once again thanks guys
Title: Re: exhaust leak
Post by: Motorrad on October 12, 2011, 01:40:44 AM
Doubble crush washer. And COPPER high temp RTV.  It holds better in my experience..   (antique bike tested)
Title: Re: exhaust leak
Post by: kxpegger on October 12, 2011, 01:46:09 AM
I used to get about 5 or 6 rides out of mine until I stopped using the POS FMF O-rings. The OEM O-rings have been in for about a year now with some help from high temp RTV they still aren't leaking. FMF O-rings suck!
Title: Re: exhaust leak
Post by: Foxx4Beaver on October 12, 2011, 04:33:36 AM
another thing to look at is how sloppy is your pipe to cylinder connection...after time the cylinder opening for the pipe gets wider because of wear and time.This happened to my 95 KX5,and I had to send out the cylinder to have the exhaust port welded to O.E.M specs...now it's tight as can be,and I only use stock o-rings without RTV and it never leaks.
Title: Re: exhaust leak
Post by: 91kawifive00 on October 12, 2011, 06:25:47 AM
I used to get about 5 or 6 rides out of mine until I stopped using the POS FMF O-rings. The OEM O-rings have been in for about a year now with some help from high temp RTV they still aren't leaking. FMF O-rings suck!

yea thats what im running in there right now the fmf o-rings. they worked for about 5-6 rides as you allready stated. im gonna give all these suggestions a try and see what works. the cylinder doesn't look badly worn to where i would have to send it out.
Title: Re: exhaust leak
Post by: 91kawifive00 on October 12, 2011, 06:27:19 AM
Doubble crush washer. And COPPER high temp RTV.  It holds better in my experience..   (antique bike tested)

hmmm... this is interesting. would you have anything i could look at to get a visual?
Title: Re: exhaust leak
Post by: Foxx4Beaver on October 12, 2011, 07:41:18 AM
just clean everything up real good,put two new o-rings on,slide the pipe into the cylinder and bolt it up and put the springs on.....once it's all secured how it's supposed to be,grab on to the pipe where it comes out of the cylinder and try to move the pipe around...if you have an 1/8 of play or more..(mine was almost 1/4"),then you might want to send it out to have it closed up a bit.Mine's almost too tight....but it's way better than having the front of your motor and frame looking like Exxon Valdez!!!

Foxx