This is a discussion on 1983 GS650L Cafe Racer Build. No seriously. within the Project Builds forums, part of the Caferacer.net Forums category; Just picked up this beat down gs650 for a cafe racer build. The shafty isn't the best candidate for a racer but it's what I ...
Just picked up this beat down gs650 for a cafe racer build. The shafty isn't the best candidate for a racer but it's what I have. Much of this especially carburetor tuning will be a learning process.
Going to post progress from start to finish. Compared to those on this forum I'm a novice, and I hope to leech some experience from the community.
Last edited by flipmotorcycles; 12-07-2015 at 04:42 PM.
Good luck. My advice is that you get it running before you dismantle it. Start with cleaning the carburetors and then put it back together at least to the point that it will run and idle. Then consider what needs to be done to make the rest of it a complete and running motorcycle. If you tear down the engine to pieces and start changing out parts and leaving things off right from the start, the bike might never run properly again. Good luck.
oops I said that twice didn't I … well good luck again anyway
Hey Thanks TrialsRider! I'm going to leave the performance tweaking to the end so I can see if I can notice any differences between them and stock.
Previous owner stated someone cut all the wiring when the bike was parked on the street. He couldn't figure it out and gave up. I went through all the grounds and the hot wire and turns out it was a combination of improper grounds and the clutch safety switch wired improperly. Took me 8 hours of fiddling, but now I can make my own wiring harnesses. Sprayed some starter fluid and she fired away. Did a compression test and she fired on all cylinders.
I have a two week window to invest a lot of time into this project. I've been working on it for the past few days...
stripped the entire bike, primer/paint/clear frame, threw all the rusty / oxidized pieces into a vinegar bath to soak after taking out some rubber gaskets just in case.
Got the wheels painted. Came out nicer then I expected and should be okay for awhile.
The carbs are in one piece but the diaphragms are dry. Not quite crusty but bone dry... (no tears or holes) Is this something I should be worried about?
I'm going to run open headers with exhaust tips and k&n filters eliminating the airbox. It's my first time jetting and I'm not sure if I should get the dynojet kit or if I'm suppose to just buy a bunch jets and do trial and error? Drilling holes into my carbs seems off for some reason...
Last edited by flipmotorcycles; 10-04-2015 at 01:45 PM.
The part you should worry about is CV carbs in general, they are a [email protected]#$% to work with once you start changing other things. It's hard enough just to get CV carbs to run good when everything is bone stock and new. Constant velocity carbs are the epitome of carburetor design complexity and the only reason manufacturers went to CV's was so the the bike could pass emission standards of the time. They basically use as little fuel as possible and make the motor run as lean as possible. Everything you change on the intake and exhaust sides to open things up is contrary to that design criteria.
The only reason you are needing to drill out anything, is because the manufacturer sealed those jets up to prevent you from defaulting the pollution control measurers.
Last edited by flipmotorcycles; 12-07-2015 at 03:52 PM.
Did your carbs look this bad, or have you got in there yet?
… everything you need to be concerned with for the first cleaning is right here in the bottom half of the carburetors:
Carburetor cleaner didn't even touch this stuff, I had to carefully remove all the jets and put them into an ultrasonic cleaner for better then an hour.
The ultrasonic cleaning leaves the brass tarnished and black so more cleaning is still needed on those parts. I'm trying to do this rebuild on near to no money so all the original carb parts are going back in for the first attempt.
The green stain is the result of copper leaching out of all the brass parts, after sitting in old fuel that has constantly been evaporating out of the float bowls. This is one of the reasons carburetors suck compared to Fuel Injection (FI) systems, in FI system the only due evaporation occurs from inside the fuel tank.
Carbs have been cleaned recently, or it's been in a bubble somewhere
Got the tank painted. Now I know why paint jobs cost thousands.
First time using bondo to smooth out the emblem bracket was not fun.
Going to replace valve cover gasket and all exterior gaskets, since they seem to have deteriorated over time.
and the plugs came off looking like this
Last edited by flipmotorcycles; 12-07-2015 at 03:56 PM.
Did you read anything on this site before tearing stuff off?
You are doing it wrong
You may have figured out (at least I hope it became obvious) that you were supposed to take the chrome caps off the ends of the valve cover BEFORE you removed the cover. Also, why are you looking to replace rings and gaskets on the engine? Do you know if it runs? Have you done any compression or leak down checks? Is there ANY indication that the engine needs to be rebuilt? Those motors are pretty bulletproof, and I doubt that there is ANY reason whatsoever to do a full rebuild on it.....specially when you have exhibited a pretty profound lake of experience with these things. That isn't an insult. Everyone has to start somewhere, but that is pretty much going straight to the deep end before even testing the water in the shallow end!