'78 GS550 rebuild questions

[XL-erate]

Hi folks!

I have a '78 GS550, or part of one. I want to build a bike and the engine in this one may be the best of 3 choices I currently have. This is the engine I mentioned in other threads that has no carbs, unknown condition. The 550 displacement and power is just about perfect for my needs I think.

I'v never rebuilt a multi-cylinder M/C engine, just some little singles, but a lifelong mechanic. How difficult of a job to do the cams, valves and timing chain or other normal rebuild stuff? I mean the assembly process, and mainly cam timing. No manual yet, and looked under search but couldn't find anything.

Is it a hair-pulling nightmare to rebuild this particular engine, or would you have any tips? Any suggestions where to get more info? Thanks for any help. I'm down near Bakersfield CA for what it's worth.

[Nessism]

Rebuilding the top end of your engine is not difficult but it is expensive and time consuming. You don’t mention what you want to do to the engine but even limiting the freshening to new rings, gaskets, and seals will rack up about $250 for parts. Splitting the crankcase to gain access to the bottom end escalates the work involved by a factor of two (at least), and further adds cost.

My strong suggestion is to find a more complete bike where you can focus on the basics like rebuilding the carbs and brake system. Most newbies around here at GSR find these rudimentary tasks overwhelming by themselves thus this would be a good starting point for someone to learn.

Good luck.

[Jackrp]

Hi folks!

I have a '78 GS550, or part of one. I want to build a bike and the engine in this one may be the best of 3 choices I currently have. This is the engine I mentioned in other threads that has no carbs, unknown condition. The 550 displacement and power is just about perfect for my needs I think.

I'v never rebuilt a multi-cylinder M/C engine, just some little singles, but a lifelong mechanic. How difficult of a job to do the cams, valves and timing chain or other normal rebuild stuff? I mean the assembly process, and mainly cam timing. No manual yet, and looked under search but couldn't find anything.

Is it a hair-pulling nightmare to rebuild this particular engine, or would you have any tips? Any suggestions where to get more info? Thanks for any help. I'm down near Bakersfield CA for what it's worth.

As far as valve/cam timing/if you can do 1 cyl you can do 4 very easy.Like previous post.depending on how far you tear it down in the costs for gaskets and orings the tough part.

[XL-erate]

Thanks, guys, and good advice!

I've been a mechanic for over 40 years but never did that many bikes, and no 4 cylinders. Doesn't seem like I can afford even a basket case but maybe, and no doubt a whole lot cheaper and easier in the long run. Sure wouldn't want to split the cases or try the gearbox! That advice helps my decision making, thanks!

[Nessism]

Thanks, guys, and good advice!

I've been a mechanic for over 40 years but never did that many bikes, and no 4 cylinders. Doesn't seem like I can afford even a basket case but maybe, and no doubt a whole lot cheaper and easier in the long run. Sure wouldn't want to split the cases or try the gearbox! That advice helps my decision making, thanks!

Splitting the cases would be child's play for a mechanic with 40 years experience. I did my first full motorcycle engine rebuild when in high school with zero years experience.8-[

[catbed]

I did my first full motorcycle engine rebuild when in high school with zero years experience.8-[

same here, a certain 850.


its not really that hard, just get a manual and follow it. it was pretty easy for me. you should have no problems since you worked on engines before. i worked on lawnmower engines.

[XL-erate]

Hmmmm..... Well then that means I am faced squarely with a win-win situation!

If I choose not to rebuild it that's a good decision and saves me time and money, possibly better spent elsewhere. On the other hand if I choose instead to rebuild, it's not a screamin big deal to do and I can expect success. Not that often I hear several different folks tell me exactly what I want to hear! :-D

Thanks guys, I appreciate it.