Trying to bring a R90/6 back to life.

[bluecycle3]

Just picked up a 76 R90/6, dont think it has been running since about 88. The po had put a battery in it about 2 years ago but i dont think its any good. My question is when i put the battery tender on it , there was a buzzing noise coming from the headlight bucket, this is with the key off which really threw me. any ideas as to what this could be?

I have a new gel battery coming, just so i know that isnt the problem. i got into the headlight bucket a little and the board in there has a few melted posts. is it a good idea to replace the whole board?


Should i rebuild the carbs before i start it or just see what happens? im thinking that as long as it has been idle that the gaskets and jets could be toast. what about the petcocks? rebuild or just wait for the usual leaks?



Any advice appreciated. thanks greg

 

[barryg]

The headlight bucket of a /6 is full of electrical components. Yes if the board is toast by all means replace it. I'ts a 30 year old bike, so it's bound to have some problems and glitches. I'm a component fixing kinda of shadetree mechanic. U address one problem, then move downstream to the next likely problem area, take care of those problems, then move on to the next downstream problem. It's a slow tedious process, but it works for me. I'm in the process of doing a total renovation on a '74 R90. The price of a lot of the BMW oem parts have gone thru the roof in the last few years. It really makes it hard on the guy who doesn't have deep pockets. In my case, my R90 has carrried me probably 200,000 miles as a rough old rat bike. Now it's in the process of becoming the show bike it deserves to be. Good luck with your project.

 

[ducatipaso]

I would most certainly agree with the post above... it's a slow process, but eventually you'll get 'er on the road. The R80 I'm riding these days came from a similar situation. Change all the fluids, buy a new battery, don't mess with someone else's junk. If you're getting a relay buzzing, swap out the relay with a new one. Arrest yourself to the fact that this bike will be ready for NEXT riding season and you'll be much happier with the end result. Good luck.

edit: yes, rebuild the carbs

 

[bluecycle3]

bringing an R90 back

thanks for the advise guys. I thought that was a relay buzz myself, glad to see i might have been on the right track. also good advise about looking forward to next season, i just dont know if i have the patience . thanks again

 

[TGHSMITH]

it all depends if the bike was sitting or stored, rebuilding the is carbs cheap insurance to isolate other problems, (butterfly shaft shouldnt need it but most of the old o-rings are most likely trash or soon will be when they get wet again, same for the floats and needles) one by one pull , clean and reinstall each electrical conection. same for the grounding areas of the diode board. remove , clean, lube and reinstall advance unit.set valves, change oils. remove clean and lube thrust bearing on clutch rod(many sitting bikes this has dried out and will eat itself to death on the first startup or the first time you pull in the clutch)
if you get it running and all sounds good then start cleaning and lubing wheel bearings and everything else, best of luck