BanditRE's GS850

[BanditRE]

Well, progress lapsed on the project. I went out tonight to mount the carbs, hook up the new cables and install the airbox, but I only got as far as mounting the carbs and connecting the cables when it became painfully obvious that something is not right with my nicely rebuilt and cleaned carbs. No matter what I did with the cables, the carbs are hanging up when opened and won't close properly unless you whack the throttle closed. So I took them off once again and tried opening and closing them while they were on the bench. Same thing, you open them, the slides go up but then get hung up and won't return unless you push them down. I assume at this point I have a sticky slide(s). Back to carb surgery again when time allows. Kicking myself for not checking this more when I had them opened up for rebuilding a few months ago. Rookie mistake I guess.

[Big T]

start by removing the return spring and see what happens then when you move the slides

Next step is to remove the throttle shaft position lock between 1&2

[azr]

Did you do a proper bench synch when you put them together? spray the slides with a bit of carb cleaner and see if that helps as well.

[BanditRE]

Thanks guys. Yes, I did a bench synch to ensure they opened and closed together and the gap at the base of the slide was the same for all four. I seem to remember some minor stickiness back then but nothing like this

I took the return spring off, the slides were still tight. Took the shaft lock tab off, still tight. So I took out the shaft and tried opening each slide individually without the shaft in place. #3 and #4 were fine, #1 was tighter than it should be, but #2 was waaaaaaaaaay too tight. I had to pull quite hard to get it out of the carb body. It definitely wasn't like that when I put these back together a month or two ago. Its colder now which could account for something but this ain't right. I've had them wrapped up tight and bagged to keep any dust out of them.

Can you swap slides between carb bodies? I assume they're all the same. When I reassembled them, everything went back together the way it came apart assuming it was right when I took it apart.

Can I sand or polish the slides until they fit better?

I played around with different slides in different carbs and all slides move well in #3 and #4 and they're all tight in #1 and #2. Which tells me I should be polishing the carb body and not the slide, I guess. But that means I got to take these !@#$% things apart again.

[Big T]

Don't use any abrasive on the slides, the coating is critical

Disassemble the carbs and scrub the bores of 1&2 with an SOS pad and a bit of water, then rinse in hot water and blow dry. That should remove whatever residue is in the carb body. Again, no sanding in there

[wymple]

I have polished slides with very fine steel wool without any negative results. It would take an awful lot of work to remove enough of anything to measure.

[BanditRE]

Thanks for the help. I'll get back into 1 and 2 and see what I can do.

Looks like i managed to scratch the #2 slide lengthwise when I removed it. Any advise on whether I should leave it or try to polish them out?

I'll give the bores a good cleaning but I'm confused why their tight after being cleaned when they must have worked fine for years and years. I'm also confused why their tight now and weren't a few months ago. The end result is the same, but if anyone has an answer to why this happened, I'd be interested. It must have been something I've done, but what I can't figure out.

I've really enjoyed working on this bike and fixing it up. It was sure to be taken to the junk yard if I hadn't bought it and its good to know I've saved it from that fate. I'll get it running and looking good, but this is the first 4 cylinder bike I've really had to work on. I've had other 4 cylinders in the past but I'd only maintained them. I think when I decide to do this kind of restoration type of thing again, I may be looking for a twin! Four cylinders, 8 valves, 4 carbs, 8 boots, man its a lot of extra hassle! Alright, stop whining, and get on with it already.

[Big T]

Pay particular attention to the small boss inside the carb bore that locates the slot in the slide, its your most likely culprit

[BanditRE]

Thanks T. Spent the afternoon taking them apart and looking for the problem. I cleaned up the slides with soap and water and used a little toothpaste to 'polish' them as best I could without stripping the finish. Seemed to work well. That was about the mildest polish I could think of. No scratches and very smooth to the touch.

The bores just seemed too tight in general. The little boss didn't seem to be causing a problem. It was just too tight to move smoothly through the bore.
The #1 bore took about 2 or 3 rounds of polishing and cleaning until the slide moved with just a little resistance from the bore.
The #2 bore took a fair amount more. About 2 hours of polishing, cleaning, checking.......rinse and repeat, until it felt right.
Cleaned everything, reassembled and they moved far better than they had. Hooked up the throttle shaft, return spring etc. and they now close with a very satisfying thwack.
Success! I can only assume I had some type of oxidation form on the pot metal that gummed things up. If they work when installed on the bike, I was thinking of spraying some fogging oil down the top of the slides to keep it from happening again when it sits over the winter.

Thanks for your help, guys, much appreciated.

I have to reinstall them on the bike and hook up the cables but that should go a lot more smoothly than last time.

[BanditRE]

A sense of accomplishment today. Carbs are mounted, airbox is on, cables are connected, adjusted and working. All the hoses are on and its starting to look like an engine again!









I probably won't have time to get in running yet this winter. The next few weekends are busy, the leaves are falling and the old bikes tank is full of crud and needs major cleaning. Still, its starting to come together, and that feels pretty darn good.

[Vmass]

You're doing a great job! I think it's great seeing a bike that has been sitting for years come back to life.

I'm looking forward to watching your project progress.

I had pretty good result with Aircraft stripper recently, on a set of forks in similar condition as your clutch cover. A couple of coats of the stripper, followed by a quick scrub with a scotch brite pad and then hand polish. This resulted in a fairly original look.

[BanditRE]

Thank you. Its been a fun process. I wasn't sure how much I'd enjoy it when I decided to give it a whirl. I've maintained bikes for years and done the odd repair here and there as needed, but there's a lot of firsts for me on this project. I was concerned after a few months I may get bored or too busy with other things and then it would lay around gathering dust. But I haven't had any issues like that, I've thoroughly enjoyed it. Except for the !@#$% stuck bolt in the cylinder head cover that cost me several weeks, things have gone pretty well overall. I still have the rear wheel and brakes to rebuild and clean up, the gas tank to clean and then likely a fair amount of tweaking and noodling around to get it to run right. I should be able to do all that in the spring, get some new tires and get this bike moving again. I was looking into an electronic ignition system also. I've never enjoyed points.

There are some cosmetic things I can do over the winter in the basement, but I don't think the wife will be too happy if I start spraying aircraft stripper down there! I guess that'll have to wait until spring as well, when the garage reopens.

Anyway, its been fun, I've learned a lot and this site and the folks here have been a massive help.

[Chris]

You're doing a great job. It's always good to see an old Suzy getting some love.

It was a lucky day for that old bike when you brought it home.

[BanditRE]

Its been a few weeks. Works been crazy and all the leaves have been falling making for some not-so-fun weekends. Its getting colder too, so last weekend before I put the bikes up for the season, I dismantled the rear end of the Suzook so I have a few minor winter projects to do.

Cowl, lights, shocks and the rear brakes came off.....



See now.......compared to the fancy "new" rotors on the front, this just ain't gonna cut it.



Taking the rear wheel off, I couldn't believe how much it weighed! I guess un-sprung weight wasn't high on the priorities back then!

So, I got two wheels to clean up and get new rubber for. I have to rebuild the rear brakes, replace the shocks, see if can make the rear turn signals to polish up a little. Maybe some cosmetic repairs to the cowl too as it got gouged out from the old sissy bar that was installed for years before I bought it. We'll see what the winter brings! Thanks for all your help throughout this project so far. Hopefully this old girl should be back on the road for late spring, early summer. I'm looking forward to that day.

[eil]

Coming along nicely, can't wait to see the result! I'm thinking there needs to be a SE Michigan meetup in the spring.