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How hard is it to do an engine/transmission swap?
Story is (and yes I was a complete sucker.), bought a non running bike 82 virago from a guy. Wasn't running and all he told me is that it had been sitting for at least a year. He didn't say much else was wrong with it. Ok So I rebuilt the carbs but knew I couldn't rebuild the fork seals and check some other stuff since I have never owned a bike before. Well, this year I finally decided to see about the other repairs and took it to a shop to check it over and a few other things.
Well The shop guy didn't check it out like he should have. the rear brake light does work with the front brake lever but not with the rear brake level. Simple check but obvious he didn't even look. The other thing he didn't check was to see if it moves.
Right, The guy that sold it to me never told me that he beat the snot out of the bike and really damaged the transmission. And the repair shop guy never checked. So now I have put about a grand into it this year for a nicely running paperweight.
I have a line on another motor/transmission to do a swap. That place told me that the cylinders have good compression and it shifts fine. But not knowing if it will transfer power properly under load, make me wary. I also have no idea on how to rebuild a motorcycle transmission and I know it is quite involved.
long story I know, and all I had wanted was a entry level bike i can ride without breaking the bank and the repairs are heading in that direction. If I scrap it I will be out about 1K that will hurt at this time. seeing that I had bought a house in Jan and have been doing some updating. things are a on the tight side at the moment.
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If the virago is like most japanese bikes, the motor and trans share the case. You have to split the case to do trans work and while its apart you may as well put new pistons, rings, bearings, etc. Bikes like most HD's and some other models (ducati superbikes) you can do the trans without touching the motor.
Now swapping motors really isnt rocket science, it can be a pita with where things are mounted. SOmetimes the bike will need special sockets, but some of those can be improvised. You will need a way to support the bike upright (a table lift is great). Some motors come out rather easy, some come out from the side, some you just unbolt the lower cradle of the frame and drop it down with a scissor jack, but remember they are around 75-140lbs so two to three people is a good idea. Also having more people adds more eyes to see the hidden wire, bolt, hose no one undid before trying to pull the motor.
Generally motors from the same generation of bike are interchangable. They dont change electrics much until the next generation model. Even then the electric parts from the old bike will bolt and work ont he new motor. Ie SV650's. 1st gen (99-02) are carbed, 2nd gen (03-09) are FI. Different electrics, but the motors are interchangeable and you just have to switch the electrics and fuel system on the motor.
Fork seals are simple. With how old it is a fork refresh is a good idea. New seals (use OEM, forget trying LeakProof), slide bearings and new oil. Just need to find the correct oil level (usually in the service manual). Being its a standard style fork its not hard, cartridge forks on the other hand require special tools. Again to do them you need a way to support the bike with the front end off (fork usually will slide out of the triples when you loosen the pinch bolts). Since you redid the forks, may as well pick up a new shock(s) (denniskirk.com probably will have some that fit it). New brake pads/shoes, new brake fluid and tires if they need replacing (again dennis kirk for them). Bike then should ride like new. You really do need the factory manual for the bike to do the forks though. CLymer and Haynes ones usually are wrong about some things and suspension isnt a place to screw up.