I have found play at the rod 78 GS550

[rgierer]

This 550 has had outrageous clatter since I have owned it. I went through all the easy fixes and finally decided I would pull the head and just go through the bike to find the problem. I have pulled the head and jugs and dissassembled and cleaned up the head and was doing a walk through with the pistons before I prepared for reassembly. I found the #2 piston to have some slap in it and it was the first time I found anything to explain the bikes noise. I hoped it was the wrist pin or piston, but after pulling the piston I found the play to continue in the rod.

When I look at the schematic in my clymers manual it does not appear the rod has any bolts holding it in place and that if I am going to repair this I will need to split the case and work from the ground up.

looking for insights.

[SPARKSS]

Your understanding is correct. The crank disassembly / reassembly is a precision pressed and degreed event........better left to the services of a bike engine shop (without knowing your own capability!).

[Nessism]

The rods are one piece with a roller element bearing on the big end. Suzuki built up the crank/rods by pressing them together under high pressure as a hold over from their two cycle days when all cranks were made that way.

Sounds like your best course is to source a used crank; the old crank can be serviced but it's going to cost a lot of money. Ebay is full of used cranks - many with low mileage. Splitting the cases is manditory of course.

Good luck.

[Dave8338]

What he said...

[rgierer]

Do you think the crtank from an 81 550L would work?

[rgierer]

a cursory review of bakie bandit leads me to believe I could put the 81 550L crank in the 78 5550. I just have to be content to spend the time. but then again I have other bikes, so I could take the time.

[first timer]

robin, you seen this right?

http://www.thegsresources.com/_forum/showthread.php?t=113917

back to topic, yeah i think you are going to need to pull the crank, i think all the 550 cranks are the same, i do rember seeing some thing when looking through the manual that made the 77-79 550 motor slightly different then the 80-82 550's ( besides the head) so you may want to dig through the manuel and see want you can find. i would focus more on trying to find a pre-80's crank to be on the safe side the model shouldn't matter, but maybe the years will.

[Nessism]

Pre 1980 engines have a kick starter and points but I don't think the crank is different...not sure though. I think you are on the right track by checking the part number interchangability.

[rgierer]

Thanks Ryan

BTW Bike bandit is pretty convincing that the early 80's L are god cranks with the late 70's. Of course I could always be surprised.

[Nessism]

Alpha Sport's parts listing shows the cranks are interchangeable between the years. There are a few different part numbers but when you click on them they all superceed to the same part numbers.