So to make a long story longer, I decided to ride my 1981 R80g/s to Port Angeles from Portland a couple days before christmas to join family. All was well until about 50 miles before my destination and my bike was surging and cutting out. It felt similar to the effect to running out of fuel. I pulled over and the bike died. It would not start. I did three things to try to diagnose the problem. I checked my plugs and they seemed ok. I took my tank off and and checked my wire connections to my coil. One was quite corroded, the right one. I pulled it and cleaned it up and reconnected. Put the tank on and boom it started up beautifully. Rode the last 50 miles without a stutter. I concluded that it was either a bad connection on the coil or there was a bit of dirt caught in the petcock valve and closing and reopening cleared it. Next day was so nice out and was headed back to Portland to spend time with other family. The bike started fine and for 55 miles was perfect until the problem reoccured. I checked the ignition coil again and noticed it was cracked. I did a quick google and found some useful information about THE grey ignition coils prone to cracking and malfunctioning. I had an extra plug and tested coil connections by disconnecting the plug wire cap and inserting the extra plug and looked for spark. The right actually sparked fine and the left was not sparking. I waited a while because I read that if left to cool the coil will begin working again. I waited and it began to spark again. I rode the bike again and the problem occurred again and then I had a back fire that was quite loud. I decided to find other ways to get the bike home. I got a uhaul and picked the bike up. it was dark at this time and since I did not have any help to get the bike up the ramp I decided to ride it up. I started the bike and the cutout started to happen right away. I look down to the left spark plug cap and it was glowing with every fire to that plug. Then it would stop and the bike would run fine. Back and forth. I crossed my fingers, revved it up, and rode it up the ramp. Now I was thinking I also had a bad spark plug wire as well, because it was glowing through a hairline crack. I got home and ordered a new Bosch ignition coil, new wd7c+ plugs gapped between .6 - .7 mm. and new plug wires rated at 1kohm resistance. It seemed to be running better but had more resistance in idle and acceleration and more vibration. I rode home tonight and I felt a bit of surge once or twice. I started reading snowbums sight on plugs and wires and I read there that coils from 1981 - on should have 5kohm resistant plug caps or you could damage the ignition. One other vital piece of information: The night before I left, the headlight was intermittently cutting out. I got home and was moving the handle bars back and forth with the power on. Well I heard a short engage when the light cut out. I turned of the power off and investigated the wiring coming from the headlight and the control switches. Almost all of them were damaged and just twisted together and taped up. I spent most of the night soldering and properly connecting the wires until I could get back to it and do a better more thorough job. Since everything has been working fine in that department but the shorting sound could have done something. I am a bit frustrated as I bought this bike and there was a lot of poor workmanship. I have fixed a lot of things already but this is a big one and I want to make things right. I have had the biked checked out when I bought it and compression was at 130, so no problems there. I changed all the fluids, when it came to the oil, whoever changed the oil prior to my purchase had the o-ring and the shim reversed. Prior to changing the oil the oil pressure light only came on a couple of times when hard breaking and was alleviated by topping off the oil. Since the oil change the oil pressure light has not come on. I have adjusted the valves, synced the carbs with a twinmax. The bike was running beautifully until I was the thick of some cold salty downpour on the hood canal and broke down. I know this is a lot of info but just need some sound advice.
Check the ground connection at the trans as well as your battery connections. Both are pretty common sources of the problem you described, but from the sound of it, you should probably go over your whole electrical system and remove any hack work.
+1 Clean and grease all connections, especially your grounds...brown wires on our bikes. Also, I would replace both plug wires and caps with the 5k ends. Electrical is frustrating, but it gets easier and before long, you'll know where every wire goes. Get a good color wire diagram and just go through everything. Doesn't have to be all at once. Sorry you got left on the side of the road at Christmas time.
Went through nearly identical hoops shortly after getting my '81. After delivery, even with the tank on i could see a ton of e-tape and dodgy connections. PO had evidently butchered the harness to add a headlight toggle to the side of the instrument/light pod-- think he also tried to add 4-way running lights since there were a lot of extra leads heading to the blinkers. I shook my head and just resigned to deal with it later and fix piecemeal whatever crapped out first. Well. Then the ignition circuit started dead-shorting while riding. In turns. On mountain curves. Ie, at the least opportune times. I attacked the butchered harness armed with soldering gun, shrink wrap, new wire, connectors etc. I was about 10 minutes into a front-to-back inspection of the harness when i knew it was a lost cause. The harness was badly butchered, but even the unmolested runs of orig wire were in bad shape: internal corrosion of the copper, and so much insulation cracking that complete replacement was demanded. I ordered a complete R80G/S harness from Bob's for a tick over $200 (this in 2002 dollars). It was special drop from Germany, duh, but got to the west coast in a week or so. It looked flat beautiful out of the bag, and i was pleased to be eliminating electrical gremlins once and for all by replacement. Only issue was that 2 of the new harness female relay bases (starter and flasher, IIRC) didn't agree w/ my '81's relay connections. I figure some of those connections must've changed over the '81-'86 run, so i just dismantled the female terminals and refit them using the wiring schematic to agree w/ my relays Keep with it, guy. Definitely worth it in the end
Ya, I think that is going to have to be done. Even though I did a quick fix with the solder gun, all it would take is a severe blast of salt water in really cold conditions to compromise the work I did. I was just being optimistic in a time crunch situation. Even though there was evidence of bad wiring done by the PO, when I actually got in there to view all the wires, most of the other wires had crack right where most of the flexing would be occurring when steering, some just hanging by one wire. So thats why my horn doesn't work!! I checked out wiring harnesses at MAX's BMW and there are going for $212, they also sell an engine wiring harness for $46 do you recommend getting both replaced? Since this is all happening at once, I decided do upgrades as well. Got an enduralast charging system, a new Odyssey PC680 Battery as well as some solid 420 copper thread battery terminals. Any other upgrade recommendations that are prone to failure in these old bikes? Ignition? Previous replies suggested to grease the battery terminals. Dieltric grease? And currently the the positive terminal is pretty loaded up, about five battery connections. I have the main terminals, heated grips, but I haven't chased down the others. Is there a cleaner way to set the battery connections up? Thanks
A few years ago I had intermittent cutting out on my G/S and eventually the ignition pick up failed after a couple of weeks, as you suspect it may be the messy wiring is causing the problem but be aware of the possibility it is the ignition on its way out, contrary to popular belief they don't always just die but can come and go before completely expiring.
s Yep, dielectric grease. You could put a fuse block in. I had a Centech for a while, but went old tech from O'reillys. works great: <a href="https://hardwaregrrl.smugmug.com/Other/misc/16038929_6qzPj6#!i=2298843628&k=X8Xmnjn&lb=1&s=A" title="Photo & Video Sharing by SmugMug"><img src="https://hardwaregrrl.smugmug.com/Other/misc/i-X8Xmnjn/0/L/350418-L.jpg" title="Photo & Video Sharing by SmugMug" alt="Photo & Video Sharing by SmugMug"></a> As far as other upgrades, do it as it needs. Your bean can will most certainly fail. Maybe tomorrow, could be in a few years. Wait till it does then replace it with this: <a href="https://hardwaregrrl.smugmug.com/Other/misc/16038929_6qzPj6#!i=2298845014&k=XfxTtCK&lb=1&s=A" title="Photo & Video Sharing by SmugMug"><img src="https://hardwaregrrl.smugmug.com/Other/misc/i-XfxTtCK/0/L/DSC00674-L.jpg" title="Photo & Video Sharing by SmugMug" alt="Photo & Video Sharing by SmugMug"></a> Much easier to repair when it shits the bed.
Probably more out there. Something like this would probably be better than hanging sh*t off the positive terminal. Anything would be better than stacking five additional connections!!!! http://www.easternbeaver.com/Main/Wiring_Kits/Fuseboxes/fuseboxes.html No affiliation, just the first name I could remember when exercising my Google-Fu! Also I like the idea of the accessories being switched. That way if you forget the grip heaters or seat massager on, it won't kill your battery! I feel your pain with the butchered harness. I've been returning a moderately molested wiring harness to stock over the last couple years. Things are getting better! Though if you have cracked wiring, it might just be time to bite the bullet and get a new harness. Although I have been considering taking some time and soldering/heat shrinking all the connectors I can get to. Will eliminate the pesky corrosion issues.
I'll vouch for EasternBeaver gear. No connection, but I've been a happy and picky customer for years. --Bill
If you have a badly butchered main wire harness,,don't even think of solder and tape..just order a new one. Take your time and you can replace the old with new in about 4 hours..plug and play. You may or may not have to swap relay bases on 2 of the three depending on your frame layout. Gives you a chance to clean up all the other @#%#$ too. Don't forget to add 4 spacers between the high fender and lower triple clamp so you don't pinch the wire harness. Over time, all the back and forth turning will cause the wires inside to rub against each other and eventually cause a hidden short...which will drive you crazy trying find it..unless the harness lets out too much smoke.
I have bitten the bullet and ordered and ALPHA ignition. Spoke to Rick at Motorrad Electrik for a while. Super nice, very knowledgable and forthcoming with info. Hats off to him! Got a new harness on the way as well. Gulp! Hope there is an end in site. After I sort the electrical issues out, it's Final Drive, bearings and seals! Might as well get started on research: Any good threads on Final Drive Rebuilds/Shimming for R80G/S? Should I even attempt? Thanks to everyone for all the info so far. Much appreciated.
Take lots of pix of the old harness as it lays on the frame to help fit the new one. You will need to bend/mold the new harness in ways that may not seem intuitive without ref pix The engine harness shouldn't need replacement unless it was butchered too. It's small, just voltage regulator/ignition module/coil to diode board and alternator, and its ends are well sealed in good clip-type terminals running in good solid conduit, unlike the Main harness There was a long-recommended extra ground wire deal from 1000 years ago by Kari Prager. Look that up. You essentially make a wee grounding harness that connects the diode board, front timing case, and a rear starter bolt to the block Last: Rick at MotoElectrik is a treasure to airhead folks and has been for near 30 years. Highest recommendation You're on the right track, bub
That's good advice. I often wish I had taken before pictures. As far as the diode board ground, I have read that article. I believe it involves beefing up the wiring as well. I don't think it will be necessary since I am installing the enduralast charging system. Did you do anything to add support or prevent wire rubbing in vulnerable areas? Rick recommended covering the harness with corrugated plastic cover. Beemer guru recommends spacers.
8jest - try a search on this forum, or Google for final drive rebuilding - there have been a few threads From memory most have not addressed replacement of the bronze spacer between the bevel and the either needle or taper roller bearing on the drive side. The spacer sets the mesh of the pinion and bevel gears, so it is nice to have it is close as possible. These bronze spacers are available in 0.1 mm (4 thou) increments from 2.5 to 3.5mm?, so if the dimension of the existing isnt an even 0.1mm a new spacer at least the next size up is required- mine was 0.127" thick so I replaced it with a 0.130" (3.3mm) one, which I think will be close. This of course means a couple of orders, first after strip down for a bearing, spacer, gasket and seal, then for the correct shims after you have measured clearance with the new spacer fitted - the big shims are $12- each so ordering a selection isnt really an option. I was quoted $280- for replacing the large bearing , spacer and seal , included resetting the pinion to the correct mesh and reshimming the bearing. If there is a next time I will let them do it - list on parts is more than half of that, and measuring the mesh and bearing preload for the taper bearing or clearance for the needle roller is hit or miss without the correct equipment. The drive I just pulled had 8 thou preload on the needle roller even with a spacer worn 3 thou so it was probably assembled with around 12 thou preload instead of zero, FWIW around the error you would expect if you measure the clearance by crushing a few strips of solder, as suggested some places. And also just about as bad as the factory built the Oilhead drives, but that is another , long, long, story.
Do mind me asking where that quote was from? That seems pretty reasonable. I was quoted more than twice that.
Here is a link to Jorg's R80GS page, about final drives: http://jhau.maliwi.de/mot/r80gs.html#finaldrive I agree with his assessment. Unless you want to change the gear ratio or do something custom, getting a replacement final drive is better and easier than rebuilding your current drive. Opinions vary, and someone may come up with the 'best final drive rebuild company'. But it is not a home repair job for someone unfamiliar with the process and the instruments and tooling may cost as much as a good rebuild or another good used final drive. YMMV. Good luck! Edit: here is a link from Snowbum's site on rear drive information: http://bmwmotorcycletech.info/rearwhlsplines.htm p.s. Australian dollars are more than US dollars and shipping is expensive to Australia.
The quote for $280- was from Motohansa in Sydney, Australia. I obtained it around 3 years ago when I bought my G/S , and noticed a fair bit of play at the wheel rim. The drive will fit into a USPS $50- flat rate box to Oz but it would probably cost more than twice that for return postage I decided to let my drive run, and 100,000 km on it isnt much worse, so I assume it was just set up wrong, not worn out. Three stud G/S final drives are hard to find and usually expensive, but I finally found a ''good used " spare on US Ebay for $200.00. I checked it out for play in the bearing, it felt good and it was put on the shelf to be used when the play in my existing drive started to increase. However, I read a post somewhere by someone asking how hard it should be to turn a good final drive, and when I checked this one to see if I could help found out mine was stiff too. Slackening off the 8? bolts on the bearing carrier slackened off the drive bearing too, and as this was a needle roller drive which should have zero preload I surmised the bearing had been shimmed wrong, and pulled it apart. It has the later 19 ball deep groove bearing so I assume it has been rebuilt at some time. The bearing feels slightly rough and will be replaced together with the bronze spacer on the other side which shows more wear than would be expected on a unloaded spacer. For a couple of years some oilhead final drives came new from the factory with between 8 and 12 thou to much preload, and most failed between 10,000 and 30,000 km, so it is possible that my drive has seen a few years light use since it was rebuilt. If the guy who parted out the bike checked the play with the wheel still on he probably wouldn't notice the stiffness, same as the factory and the dealers didnt notice the stiff oilhead drives, so I have accepted that he sold it in good faith and will replace the bearing and spacer at my cost. The bearings are half list from Motorworks in England, $50- or so and with another $20- for the shim and spacer it will still be a cheap drive as the only other one I saw, on German Ebay, went for over EU500- , which is more than $600-. The oilhead guys ended up measuring the bearing clearance by temporary refitting the carrier with tank repair epoxy strip in the shim space, and I will use this method as it seems to have worked for them, when checked against setting with the proper tool. Then I bumped into this guy who has replaced the large deep groove ball bearing with a taper roller and convinced me I should do the same ! http://www.youtube.com/watch?v=28mPGhqDW8I
So I got the new battery and upgraded to the enduralast 400 watt charging system. I am so so happy with this upgrade!! My bike is more responsive, accelerates better, holds at higher rpms. It's like a new bike. I did not expect the charging system to have such a grand effect. New wiring harness showed up today and the alpha ignition is a week out. But I cannot wait to see how that improves the bike. One thing I notice today though is a little bit of an exhaust leak at the connection of the exhaust collector to the exhaust silencer. I tightened it as it was fairly loose but still getting seepage. Any advice in how to make that connection better. I was going to pull my exhaust apart any way to clean it up and paint it with VHT flame proof paint. So any suggestions while I am in there would be great. Thanks!
