BanditRE's GS850

[BanditRE]

Some not so good news........ran a compression test with the engine cold as it doesn't run right now. Air box off, carbs still on. #1 was at 120, #2 was at 90, #3 was at 65 and #4 was at 110psi. Squirted some oil down #2 and #3 and the values didn't change. I think that means its most likely valves, but I need to do some homework. Bummer

 

[ShadowFocus603]

Adjust your valves for sure and get it running then do the test with a warm engine and throttle wide open. Don't panic right now about the low numbers. They'll most likely come up to spec after the engine has been running awhile again.

 

[BanditRE]

Yeah, I forgot about the valves. I went back to the thread I read a few days ago and saw the "adjust valves before the test" which I didn't do. I'll finish up with the carb cleaning I started, get those put back together and then set about checking the valves. Thanks

 

[BanditRE]

Well I got the carbs off.





Two weeks later and huffing too much solvent cleaner, they're looking a whole lot better. I'm still waiting on some parts to be able to re-install them, and I have yet to get to the valves....



Many thanks for the VM Carb Cleaning tutorial on Cliffbass' website by Paul Musser. That was very useful.

 

[BanditRE]

With the carbs freshly cleaned, I was ready to get to the valve adjustment. Things were going well, until I got to one valve cover bolt. The head of the bolt sheared right off with minimal effort. I've tried what I can think of to get the cover to budge, but it will not move. There must enough corrosion between what's left of the bolt and the valve cover to hold it firmly together. I've used as much force as I dare to without risking damage to the head or cover. Any suggestions would be appreciated. I'm about to search the site now......

Picture is from the left side. Broken bolt is immediately below the rear of the breather cover. You can see a chip on the valve cover already. I'm not sure if I did that or not. Either way, that bolt ain't moving...

 

[BanditRE]

Sheesh. Almost 6 weeks since the last post. The frozen bolt in my last post, took much time and effort to remove. It is now removed, although the original threaded hole for the bolt in the cylinder was damaged during the process. A slightly larger hole was drilled and tapped and an oversize bolt installed. All new allen head bolts used now and ALL installed using anti-seize. All that work, just to get access to check the valve clearances! So a few weeks ago, I got to check the valve clearances, #1 and #4 cylinders were within tolerance, #2 and #3 cylinders were tight on inlet and exhaust.............and those were the two with low compression when tested a few weeks ago. Of the four valves that needed new shims, three of them took the next size thinner to come within spec. The remaining valve that needed adjusting, the exhaust valve on cylinder #3, needed 3 sizes thinner, it went from a 2.60x to a 2.45. It is now gapped at 0.003", at the outside of the specified range. The tight valves on the inner cylinders had obviously contributed to the initial low compression results, but that last valve was so far off, I assume the valve has been partially open for some time. That could well cause a problem down the road.

With the new shims in place and all gaps adjusted to within the spec, the compression results were much better.

#1 cylinder = 120 psi (unchanged from previously)
#2 cylinder = 110 psi (up from 90)
#3 cylinder = 105 psi (up from 65)
#4 cylinder = 110 psi (unchanged from previously)

These readings are on a cold engine with no airbox and no carbs, as the bike is still disassembled. I'm pretty happy with that, and I'll check them again once its up and running and has a few miles under its belt.

In other news, with my work being less frantic and that rusty bolt in the valve cover finally taken of, I was able to clean up the airbox, install the new filter, seal it up and get it ready for re-installation.

 

[eil]

Yay, progress! I have a boogered up bolt on my breather cover too. PO dropped the bolt on top of the cylinder in between the fins and instead of bothering to fish it out, he drove in a non-metric bolt instead, which naturally snapped when I tried to remove it. I'll get to it some day, but for now the breather cover is not leaking.

Just noticed you're pretty close by. I hail from the Ypsi/Arbor region, if you ever need a hand taking out an engine or something, let me know. I'm thinking there needs to be a regional GSR meetup soon.

 

[BanditRE]

Fasteners.........sheesh. I've had my fair share of hassles from stuck fasteners so far on this project, but the valve cover bolt was the only one that caused extended delay. I have to say it felt good to get that damn thing out, the valves adjusted and the compression back towards spec. Progress is good. Thanks for the offer of help, that's much appreciated. The engine may have to come out at some point depending on much wear the exhaust valve on #3 has seen. That old shim was likely holding the valve partially open and that could have caused some valve and seat problems. Time will tell. If I ever need help, I'll reach out to you, I'm only up M-14 and I-96 about 20-30 minutes max from Ann Arbor/Ypsi. There's always cold beer in the fridge

 

[BanditRE]

More progress on the bike. Moved on to front brakes, forks and wheel. Here are some of the front brake pictures........

Nice looking brake fluid, huh?


Frozen capiler......


Caliper apart, ready for cleaning...


Master Cylinder piston. Very nasty, a pig to disassemble, will need a complete replacement.


More lovely fluid behind the caliper piston...


Cleaned, painted and ready for the new pads, seals and lines I've ordered.....

 

[BanditRE]

After the brakes, I worked on the wheels and getting the disks cleaned up. They're not bad but I'm considering getting them resurfaced and cross-drilled by TrueDisk.



Taped up disks and painted.....


Finished product. Ready for resurfacing or re-use.

 

[BanditRE]

And after the wheel, I started on the forks. The rust cleaned up well, and all parts were ok except the fork seals. So I'll replace those and likely splurge on some new progessive springs. Used the various brake and fork tutorials available on this site for doing all this work. Many thanks to all those who created them. There was some mention in those write ups about how tricky it is to get the bolt out of the bottom of the fork, special tools required etc. I soaked it in penetrating oil for about 24 hours and then put a 8mm hex bolt in my air impact wrench. A quick blast on the impact wrench loosened the bolt without having to hold the inner fork parts in place. Worked fine.



Forks apart, oil looked pretty good. All parts looked pretty good too. The seal came out fairly easily using a seal remover I bought some years ago for $10-15




Cleaned up and ready for new seals and springs........still waiting on those in the mail.

 

[BanditRE]

Parts arrived, so its back re-assembly of the forks, brakes and master cylinder. I installed new fork seals and new progressive springs, topped off with 10w fork oil, new spacers and now two almost brand new forks.





Fork oil level tool. Purchased many moons ago when I thought I needed it. You don't. I used it again, and I think adding the specified amount and or using a soap dispenser nozzle or even a taper measure is easier and cheaper.



Then on to the master cylinder. I had ordered a new piston set for the front MC as the old one was shot. Everything went back in easily enough and according to the shop manual. I am left with two questions though. Does the final rubber dust boot looked correctly installed? Also I have a leftover plaster washer and metal clip (shown in the picture) that obviously came out of the master cylinder but as it was so covered in grunge and grime during disassembly, I'm unsure of exactly where its supposed to go or even if I need it. There's no mention of this piece in the manual at all. During removal it came out before the circlip and steel washer. But it won't fit in the recess with the new steel washer and circlip. Any advice is appreciated....

New parts......


Reassembled master cylinder.....


New rubber dust boot. Installed correctly?


Mystery plastic clip and metal piece. Any ideas?


Caliper reassembly and/or MC repeat next.

 

[Steve]

Hopefully you don't get confused by these later, but they appear to be labeled incorrectly. :-k

The left side of the bike is under your clutch hand, the right side of the bike is under your throttle hand.

.

 

[BanditRE]

Nice spot! I noticed that right after I took the picture! Its corrected now, but thanks.

 

[eil]

The plastic washer and clip are from the old dust boot, which you probably ripped apart when removing. The new one has them inside already, so the old ones can be tossed.

Hurry up, it's starting to smell like fall!

 

[BanditRE]

Ah hah! Awesome news. Thanks for that. I can smell fall coming to, but I've still got the rear end to do yet! Work heated up and I got picked for jury duty! I'll get there eventually!

 

[BanditRE]

Finally got some spare time again to work on the bike. Reassembled the calipers with a new K&L kit with new seals. I know some have criticized them but I had no problems with the kit at all. Everything went together fairly easily. I also sent the front disks out to get resurfaced and cross-drilled. I got those back on Friday and they look great. So with all that, the forks are reinstalled with the wheel on and the new disks and calipers ready. On to brake lines and controls next..........

Shiney "new" rotors. I sent them out to Tom Tokarz with Truedisk LLC. www.truedisk.net. He did a great job as you can see and had them back to me in a few days. All shipped in those USPS standard rate boxes. Cost was $70 a disk to resurface and cross-drill.





Forks installed, rotors on, wheel on and new calipers ready to go.

 

[81GS850]

Looking good, I have a small bitch to make though....


WHY did you oversize drill that hole in the head and put a bigger bolt in? They make these things called helicoils... If you ever sell this bike the next owner will be cusing you as the PO who did that rigged fix. I had an m8 exhaust bolt that was stripped and the PO decided to wallow out the hole in the head, and the flange to "fix" it. I was able to take an m12 tap and tap that hole without even drilling it bigger cause it was so wallowed out... Then I used an m12 bolt and drilled an m8 hole and tapped the bolt. They even sell an m8 insert that goes into an m12 hole... It just seems like such a "rigged" fix when you could have put a helicoil in it and stuck with the stock sized bolt.

 

[BanditRE]

Really? Ok, well if you got to know. I screwed up the cover and the cylinder head badly getting what was left of the old bolt out of the head. To make matters worse a bolt remover that I tried to use to extract the sheared bolt broke off as well. Drilling out the remnants of both the bolt and the extractor made a big mess and a large off-round hole in the head. I should have asked for help sooner than I did, but once a friend of mine came over to help we decided to get something quick and ugly to work so I could get to checking and setting the valve clearances to verify whether or not I had bad compression in the #2 and #3 cylinders. I didn't want to spend a whole lot of time trying to fix a bolt hole in a cylinder head that could have more serious problems. After checking all the valves, the #2 and 3 exhaust valves were way too tight. If it has run that way for long I'd guess the valves could well be burned. The only way to know for sure would be to take the head off and check. I reset the valves and they have decent compression, enough that the bike should run. Knowing that I'll likely have to remove the head in a year or two anyway to replace the valves and guides, I elected to leave the crappy bolt as it is. Also, I was advised against using helicoils all along in bolts that get removed and re-tightened frequently as helicoils can often fail in such applications. I'm no expert, just listening to people I know who have made the same mistakes and offered me advice. The proper way to fix it I'm told, is to remove the head, set it on a drill press to ensure the hole is straight, drill out an oversize plug and install a sleeve so I can use the same size bolt again. Not such a big deal if I already have to remove the head to replace the valves and guides. A giant pain in the ass to do now especially if I don't even know how well this bike is going to perform. So the crappy bolt remains, the rest of the bike will get fixed up, we'll see how it runs, and if its as good as people say it is, I'll fix it properly when its time to do the valves.

 

[81GS850]

Really? Ok, well if you got to know. I screwed up the cover and the cylinder head badly getting what was left of the old bolt out of the head. To make matters worse a bolt remover that I tried to use to extract the sheared bolt broke off as well. Drilling out the remnants of both the bolt and the extractor made a big mess and a large off-round hole in the head. I should have asked for help sooner than I did, but once a friend of mine came over to help we decided to get something quick and ugly to work so I could get to checking and setting the valve clearances to verify whether or not I had bad compression in the #2 and #3 cylinders. I didn't want to spend a whole lot of time trying to fix a bolt hole in a cylinder head that could have more serious problems. After checking all the valves, the #2 and 3 exhaust valves were way too tight. If it has run that way for long I'd guess the valves could well be burned. The only way to know for sure would be to take the head off and check. I reset the valves and they have decent compression, enough that the bike should run. Knowing that I'll likely have to remove the head in a year or two anyway to replace the valves and guides, I elected to leave the crappy bolt as it is. Also, I was advised against using helicoils all along in bolts that get removed and re-tightened frequently as helicoils can often fail in such applications. I'm no expert, just listening to people I know who have made the same mistakes and offered me advice. The proper way to fix it I'm told, is to remove the head, set it on a drill press to ensure the hole is straight, drill out an oversize plug and install a sleeve so I can use the same size bolt again. Not such a big deal if I already have to remove the head to replace the valves and guides. A giant pain in the ass to do now especially if I don't even know how well this bike is going to perform. So the crappy bolt remains, the rest of the bike will get fixed up, we'll see how it runs, and if its as good as people say it is, I'll fix it properly when its time to do the valves.

Hey no problem. I understand **** happens. I made one of the sleeves you mentioned. I just didn't know if the actual answer was, "because it's what I had". Don't get so upset. These bikes are fun btw.