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Yamabond sealed motorcycle cases
- Thread starter mofosheee
- Start date
- Joined
- Nov 29, 2017
- Messages
- 533
I ride an FJR and while I haven't had to split the cases I have pulled the cam cover and side covers to do valve clearance checks. The cam cover is sealed with Yamabond. I. didn't have any trouble getting the covers to release....just a few taps with a plastic mallet and it popped loose. Are you having difficulties? 
- Joined
- Nov 13, 2013
- Messages
- 104
Hi Guys
Thanks for responding.
This sheet is stupid strong and yes, I am having difficulties. British motorcycle case this time. I avoid the application of brute force method on cast aluminum. With that I'm leaning towards a multi prong approach where the forces required for separation are distributed over an area as follows;
Some heat, case puller, a machinist jack in the case and love taps using a rubber mallet. Possibly apply acetone to seams.
Cant think of anything else.
Thanks for responding.
This sheet is stupid strong and yes, I am having difficulties. British motorcycle case this time. I avoid the application of brute force method on cast aluminum. With that I'm leaning towards a multi prong approach where the forces required for separation are distributed over an area as follows;
Some heat, case puller, a machinist jack in the case and love taps using a rubber mallet. Possibly apply acetone to seams.
Cant think of anything else.
- Joined
- Aug 29, 2016
- Messages
- 838
Modern transaxles and such are gasketless with sealer. Normally there is a spot cast into each case half that is meant to be used for separating the two. Use two angled prybar/screwdrivers back to back inserted in the the gap between these lugs, then squeeze the handles together.
- Joined
- Mar 10, 2015
- Messages
- 248
Some cases have dowel pins for alignment, this makes splitting them somewhat of a challenge. I have had luck with plastic wedges to start them moving apart in a straight line.
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- Joined
- Jan 20, 2015
- Messages
- 359
Agree with navy chief, yamabond itself doesnt cause problems. Its usually the dowel(mainly hollow dowls on the bike I have worked on) that cause issues. I use UHMW wedges made from scraps and I high powered heat gun (to heat the case)
- Joined
- Apr 9, 2022
- Messages
- 2
Can you update me on any specifics that helped separate the cases? I have read the above posts after running into the same problem today. The right side gearbox cover on a 1970 Triumph is glued down shut. It is a beautifully restored bike, and there are no lugs or projects on the cover to tap on. The joke is that just this morning I told a man 'you can take apart anything with heat, vibration, and patience.' Look what the hubris brought me!
Rick