engine replacement for 1982 GS650GL

[tom203]

You deserve to have Lady Luck make a visit and get this project on track!

[William Groebe]

I received the rest of the bearings in the mail yesterday. I know what I'm doing this weekend!

[opelmanz]

hope the projects going okay I just saw the post today. if I may be so bold I don't suppose you have a 650 parts engine lying around with a good piston to spare

[William Groebe]

opelmaz, I'm going to wait to part with any spare parts until I am finished putting her all back together and she runs. But, hopefully that won't be too long.

I've had to work OT the last few weekends, but I had this last Sunday off, so I found enough time to put the bottom end together.

Before puttung enything together I measured out the oil clearance on the rods with the new bearings using plastigage.



they were all within spec, so I put all the rods on the shaft.


Then I had to put the bearings on for the crankshaft. First I laid out all the bearing boxes in order of where they will go on the shaft. Upper shaft bearings in the top row, lower bearings on the bottom row. And I labeled each bearing with a sharpie, just in case I forget which box each one came from.



I laid a piece of plastigage on each bearing, torqued the engine down and pulled it open again to read the oil clearance. They are all within spec!



I spent the rest of the day putting the lower end of the engine back together. Now I just need one more full day to put the top end in and put the engine back on the bike and I'll hopefully be on two wheels. I'll probably have to wait for Saturday.

[tom203]

You should make technical manuals! Thanks for updates with great pics.

[1948man]

You're a brave man. Hope everything works great for you.

[William Groebe]

I found bits and pieces of time over the last few days to get the bike back together by last night. I was going to test it out this morning, but realized I'd left the battery charging on my battery tender at 6v instead of 12v. Whoops. I hooked the battery back up to the charger at 12v and will try to start it up when I get off work tonight.

There were a few minor hiccups, which I'll detail below. The first of which is that I stripped one of the holes for the bolts for the signal generator assembly. They are 6mm bolts and with all the tearing down and putting back together I managed to lose all the thread in the engine hole for one of the bolts. I'll search the forum for the best way to fix this.


For now here's my usual pics of the process.

First off I had to install the pistons. When putting one of the circlips back in to hold the pin I lost control of it in my tweezers and it flew off into my garage never to be seen again. Luckily I had the parts bike to pilfer a circlip from. No time lost.


Dropping the cylinders onto the pistons is tricky without a special tool to clamp the piston rings, but I found that using a tape measure wrapped around the piston rings works well.




I had to change out a few of my shims. I can't have .15mm clearance!!
I don't have a valve puller tool, so I had to torque down the camshafts, check the clearance, remove the camshafts, replace the shims, then retorque down the camshafts.


Then I had to get the engine back on the bike. Same way I got it off. I found it easier getting the engine on and off the frame with the valve cover off. Gives you just a bit more clearance.
On a side note, see how the right turn signal which I'd carefully taped to the fender came loose and I didn't notice. Well the wire snapped off, so I need to rewire my turn signal. No big deal.





Time to put the valve cover on, and the exhaust I picked off the parts bike.


Looks like a motorcycle again, minus a few flaws: the stripped bolt hole for the signal generator cover, the rewiring of the turn signal, and no battery yet.
I'll hopefully fix everything but the stripped hole tonight and take her out for a spin around the neighborhood. Wish me luck.

[William Groebe]

I couldn't get her started tonight. The battery had charged up during the day, but I couldn't get the engine to start. The starter motor is going strong and there is spark in the spark plugs, though when I tested them out unplugged they sparked but the spark spark was pretty small. It was the first time I tested out spark plugs that way so I could be doing something wrong there. Or maybe the battery just needs to charge more to supply more spark.

I wore the battery down trying to start her up. Turned the tank to reserve. I even primed it for a minute before gas started leaking out of the carbureters. Probably a bad idea. I'll check my compression tomorrow and try to start her up again.

This same thing happened when I replaced the transmission. It took an hour or so before the engine actually came to life for the first time. I didn't have to do anything special, but just wait for the engine to wake up from a long slumber, and then it started up without fail every morning. But this time I tried for more than an hour. I'm a little disheartened, but I'll try again in the morning. I just don't want to drive my neighbors crazy with the starter motor. It's worse than screeching cats.

[tom203]

Amazing! Check to make sure " choke" is fully engaged at each carb end - when I first got my bike , it wouldn't start up from cold unless the choke plungers were fully pulled out- half way wasn't adequate.
Of course, the carbs shouldn't leak after a minute of prime, but that problem might cure itself.
No valve bucket depressor? Just use zip tie method - it's easier. No need to remove camshaft which will just distort your readings/guesses when it's bolted back down.

edit: try a 1/4 inch screw for signal generator, the extra .010 might grab enough

[60ratrod]

Will, the best way to fix that is to get a helicoil kit. Napa has them. I wouldn't hesitate to helicoil that. And i would also try some starting fluid to see if it fires up. Have you checked to see if you are getting spark? Weak spark/no spark will keep you from getting down the road. Looks great otherwise

[William Groebe]

Ok, so I fixed the turn signal wire by vulturing a good wire from the parts bike, so I can check that off my to-do list.

I'll be buying the helicoil kit to fix the stripped bolt hole in the signal generator cover. No biggie.

But the main problem is that the bike still won't turn over. I've got 13 volts on my battery, the headlight turns on, the signals work, and the starter works, but I can't get ignition. I filled the tank with new gas and set the petcock to reserve. I bought new spark plugs as the spark was really small when I pulled the plugs and tested them. But the spark on the new plugs are just as small as the original plugs. I just get a very small spark within the plug gap. Not sure how normal that is though as I never tested the spark plugs out before.

I haven't done anything to the carbs since I purchased the bike. I've been trying to handle one issue at a time and reduce the amount of variables as I proceed. I suppose pulling them apart for a good inspection and cleaning would be a good thing to check, but I wanted to get the bike running first. The carbs never had an obvious problem before so even though they may need a cleaning, I don't think they are the cause of my non start situation.

60ratrod, you suggested using starter fluid. I'll buy some today and try that out next before I move on to any carbureter work.

[yank]

Starter fluid!! And if it starts what are you going to do? Save yourself time and money pull the carbs, I would not use the starting fluid.

[William Groebe]

I tried starter fluid and she started up just fine, and then she keeps running. After using starter fluid a couple of times I tried without fluid and she starts up every time without fail. WAHOO! A bunch of crap blew out of the mufflers (new from the donor bike) so perhaps there was too much crap in there that kept the whole bike from running. I don't have time to do any work on her tonight. Actually my whole week is booked, so I won't be able to do any more work until after this weekend. But I am at least happy to hear her running again. She's idling high, but I probably need to adjust the idle screw as it got knocked around a bit during this whole process. Thanks for all the help and I'll keep you all up to speed once I get time to get back in there. Thanks for all the help so far.

[tom203]

The "choke" circuit is a seperate passage from other carb circuits. There is a small hole in each fuel bowl that feeds a passage up to carb throat- this system might be restricted/plugged on one or more of your carbs causing hard cold start . Starter fluid bypasses this , but use it sparingly.

[60ratrod]

Will, what color was the spark? It should be a nice purplish-blue spark. I would also consider doing a full strip and dip as per the tutorial if she doesn't cold start without the starting fluid. Glad to hear you got the ole franken-girl going. If she doesn't run right the i would definitely do a strip and dip after a test ride or two.