What would you do?

[markjs]

OK, assuming I fix my XS400J-K motors to make one tight motor with a good gearbox. Would you pull the top off the '82 engine and install it to the solid '83 bottom end, or, alternatively leave the perfectly good top intact and split the bottom of the '82 engine's case and swap out the tranny parts. Right now I am thinking the experience with the tranny is enticing and may actually end up an easier job in the long run. Anyone got an opinion?

 

[Scorpio1963]

If I understand the question compltely I think the answer is obvious.You need cheap and reliable transportation it would probaly be easier and faster to make the swap according to the info that 83 bottom end is solid.If theres any doubt then exploring the gear box would be an option.Theres plenty of online diagrams that show how these are assembled and break down on schematics of what parts go where.My 02 cents anyways.

 

[crashcourse]

I think it would be much easier to swap the good top onto the solid bottom. You can still play with the other tranny without risking getting in over your head.

 

[markjs]

Well the reason I really want to go the other way is because I have a complete gasket set for the engine, aside from the head and base gaskets, so it probably would not cost anything. How hard can a tranny be to swap out some shafts?

 

[markjs]

I may not have a lower case gasket, but even so, I guarantee that will be cheaper than a cylinder head and base gasket set.

 

[Scorpio1963]

Well the reason I really want to go the other way is because I have a complete gasket set for the engine, aside from the head and base gaskets, so it probably would not cost anything. How hard can a tranny be to swap out some shafts?

So this was trick question
Im with crashcourse and my original opinion all day.Get you bike put back together with what you have that will work.
Save the bad gear box for a rainy day

 

[markjs]

Well if it keeps running like it is, maybe it's fine. I am not confident, but it runs for now, so I will just be easy on it till I get my 700, then I can start getting serious about repairing the XS400K.