Transmission leak from stud

Transmission, clutch, chains and belts
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Joined: Wed May 04, 2005 4:17 pm

Transmission leak from stud


Post by 03Roadking » Wed Dec 28, 2005 11:29 am

Description: I found that the leak is one of the studs on the bottom of the trans

Post by 03Roadking on Aug 5, 2005, 8:08pm

I checked back 400 days and 200 threads Maybe someone remembers or knows this
I replaced the main seal behind the sprocket three times but this last time I didn't put it all back together I let it set for two days with all the sheet metal off I found that the leak is one of the studs on the bottom of the trans Someone once posted about the paper trick or tape trick I assume they were referring to plumbers tape on the threads of the stud but I want to be sure, if anyone knows or remembers please reply
I know the proper way is to weld and re-tap but I sure would like to ride the rest of summer before tearing it down

Post by RussW on Aug 5, 2005, 9:45pm

Another option, they make those mount studs in a couple of oversizes should the stud be too loose a fit to be sealed with tape. Stock is 3/8-16x3/8-24, you can get 7/16-14x3/8-24, and 1/2-13x3/8-24. Should save you from a tear-down and reweld, at least for a while. I saw them in the J&P catalogue, but should be available from others.

Post by Red55FL on Aug 6, 2005, 1:36am

If it were my bike & the stud is not loose in the threads, I would---
Drain the oil out of the trans.
Remove the stud.
Clean the stud and the threads in the case with CRC contact cleaner or a good brake cleaner.
Reinstall the stud with Lock Tight (red or blue).
Let it set over night, then reassemble everything and refill the trans.
Ride it and check for leaks.
If the threads are worn to the point you can feel slop in them, use three or four wraps of Teflon tape on the studs after cleaning the threads.
If that doesn't work, then you may need to do as RussW said.


Post by 03Roadking on Aug 6, 2005, 5:36am

Thanks Russ and Red
I am going to pull the trans tomorrow I had it out about three weeks ago and the threads felt good and tight on all of them I hope I didn't pull the thread went I put it back in I will let you know Sunday what happens

Post by 03Roadking on Aug 11, 2005, 5:26pm

I pulled the trans last Saturday the threads felt really good but they were not tight at all when I went to pull the studs they came out very easy I cleaned the hole and the threads with brake shoe cleaner I put a drop of lock tight and a wrap of tape (I know over kill) and put them back in It have been sitting for two days without any leaks I am going to take it out tonight for a little run but I think it is taken care of
Thanks for the suggestions

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Re: Transmission leak


Post by spinner » Tue Apr 21, 2009 8:16 am

Hi RK,
I know this was posted some time ago, but how did you go with the thread seal on your gearbox studs? I have the same. Both front studs leaking, and feel loose in the thread when I removed them.
I was considering going oversize, but wanted to know how your tape and Loctite deal went off? Any info really appreciated. Many thanks and kind regards, Spinner.

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Re: Transmission leak


Post by hjans » Tue Apr 21, 2009 4:01 pm

had the same
put in teflon tape ( plumbers tape ??)
problem solved.
most easy way-most effective way-lowest cost way-safest way


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