exhaust keeps loosening up

[Jon_P]

i have finally had a chance to ride, and i have ridden to work the last couple days, yesterday i noticed a little exhaust coming out the right exhaust ring. i tightened it up. today as i was getting ready to come home i see my left side is leaking by the ring?? i got home and checked it out. the right was pretty much off?? and the left was just about out also?? but why would this happen?? worn exhaust packing rings and need new exhaust rings??/

[Bob_Roller]

How tight are you tightening the exhaust nuts ? The recommended torque is somewhere around 100 ft/lbs, I don't tighten mine that tight but pretty snug. I don't think the exhaust nut will wear out too easily, if it can strip the threads off of the cylinder head, I think it's pretty tough.

[Justin B.]

They rip the threads off by "galling".  Jon, just use a bit more torque each time you tighten them and you'll find the correct value - eventually.  Funny, I just tighten mine a hair past the "doesn't leak" point and I've never had this problem...

[Jon_P]

i know i tighen it beyond the 100 ft. i work as a mechanic for a trade and have learned what i tighten things to. now my exhaust wrench isnt that big but i know when i put my 290 lb but behind it, its tight.

i will check in a couple days and see. maybe i was just dumb or something.

[Rob Valdez 79 R65]

I must say, Jon, you have one of the most "focused" collection of bikes that I have ever seen!
All 650's and within 2 years of each other!  It was in 1980 that I bought my 1979 R65, as a leftover.


About your exhaust, well, I've never had it happen.  These days I feel lucky if I can get them off!

As long as you are working in this area, have you seen the tip I put in the Tech Tip section on cleaning up the threads with grinding compound and oil?  (I have not had the pleasure, yet, myself...)
That may be something you might want to try, and then clean them up REAL well, (per the instructions) and no doubt you are using anti-seize compound on assembly.


** And don't tip your bike over tightening the nuts! **

No, I am happy to report this is NOT a AMHIK.  But I've scared myself!

[Justin B.]

Jon, that's strange.  I figure I have in the neighborhood of 45-55 lb/ft on all of mine and have never had one loosen up.  But, you might ride a bit more "spirited" than I do...

Rob, no need to get that fancy and I would only recommend it if there is some actual light thread damage (or you feel tight spots when hand threading the nut without the pipe installed) as you are removing material from BOTH the head and nut.  I suppose somebody could eventually wind up with extremely thin threads if they carried this to excess or got too carried away.  

I buggered one up pretty bad by going about 1/8 of a turn past the tighten back up spot and spent about 2 hours with a needle file cleaning up my "mistake"  I still was not able to spin the nut back on like I wanted so lapping compound to the rescue.  I just used an acid brush and painted it on the threads, progressively screwing the nut further and backing off - like tapping a hole.  I don't think oil is necessary as I used the Clover brand valve lapping compound which is a paste.  You need to make sure it is completely flushed off when done.

[Jon_P]

i started wondering about how i do ride it, i do like to ride with the trottle in the main jets, i thought about opening my exhaust again and drive the neirbors nuts and see if the exhaust pressure is indeed pushing my pipes. next thing i guess would be to put a small flange on the end of the tubes to help???


i would love to say it was a plan to collect 650cc bikes but it just worked out that way. funny cuz there are a couple more out there that i would like to get and they are also 650's