My Airhead Needs Help - Airheads Beemer Club Forum https://www.airheads.org/community/my-airhead-needs-help/ Airheads Beemer Club Discussion Board en-US Mon, 31 Aug 2026 04:47:17 +0000 wpForo 60 Speedometer Went Whack For a Minute https://www.airheads.org/community/my-airhead-needs-help/speedometer-went-whack-for-a-minute/ Tue, 11 Aug 2026 00:15:40 +0000 I’m returning to riding after an approximately 15 year hiatus, and now retired. Picked up my new bike, an 84 R100RT in the Bay Area on Friday, and had a nice ride to our Son and family in the Santa Cruz Mtns. Leaving for out home in the Sierra Foothills Sunday morning, while going over Pacheco Pass at about 75-80 mph, I looked down and noticed the speedo pegged to the max. Once off the highway, and back to around 50mph., it stabilized and was about correct in my estimation, for the rest of the 1 1/2 hours to home.

I have the Factory Shop Manual on its’ way to me now, but want to have a look-see. I am guessing either the cable needs lubricated, or a gear is stripped. School me, please. And thank you in advance.

 

Steve

]]> My Airhead Needs Help Steven Johnson https://www.airheads.org/community/my-airhead-needs-help/speedometer-went-whack-for-a-minute/ Clutch slippage https://www.airheads.org/community/my-airhead-needs-help/clutch-slippage/ Wed, 22 Jul 2026 23:57:12 +0000 I went out today for the longest ride I've done on my R100 RS for about 400 km's. It was all highway running and on the way back at speed I noticed a little bit of clutch slippage. Just riding around low speed in town it's not noticeable as I'm not reving hard enough to make it slip. Clutch plates are a little steep so I'd rather not have to throw down right now.

 

Anyone have any thoughts?

]]> My Airhead Needs Help Mike Buhler https://www.airheads.org/community/my-airhead-needs-help/clutch-slippage/ Swing Arm Boot Oil https://www.airheads.org/community/my-airhead-needs-help/swing-arm-boot-oil/ Sat, 04 Jul 2026 20:40:30 +0000
I am slowly working my way through a 1976 R75 /6 "barn find". It is time to do the spline lube and see if the rear main seal is leaking. I took the clamps off the swing arm boot to get at the drive shaft bolts, and pulled back the top of the boot for a look and went to bed. This morning there was a good 1-2 oz of orange milky oil under the bike. I clean it up before taking a picture. I could still see some when I pulled the boot back (see photo).
 
1) Seems like quite a bit oil for something that should have none. I guess the output seal might be leaking?
2) It is orange because water got into the boot? The boot is still fairly pliable, so no major crack are apparent.
Any ideas what might have caused it and what to look for as I continue with removing the transmission?
 
Background: The previous owner bought it at auction and probably did not do anything but replace the transmission fluid.
 
]]> My Airhead Needs Help Rodney Spears https://www.airheads.org/community/my-airhead-needs-help/swing-arm-boot-oil/ R65 LS not charging https://www.airheads.org/community/my-airhead-needs-help/r65-ls-not-charging/ Wed, 17 Jun 2026 00:14:05 +0000 Since last season my '82 R65 LS hasn't been charging every time I go for a ride. Thankfully bump starting is a cinch. I checked the connections to the stator etc and all looks good. All new parts in there too. After similar issues on my Moto Guzzi that turned out to be a toasted battery I'm thinking this might the same issue with my R65. I know the same battery has been in the bike for many years so it wouldn't be any surprise. Now it's just a matter of looking up what the replacement is and try that. The Goose was solved with a new one. 

]]> My Airhead Needs Help Mike Buhler https://www.airheads.org/community/my-airhead-needs-help/r65-ls-not-charging/ 1981 R100RT Transmission repair service https://www.airheads.org/community/my-airhead-needs-help/1981-r100rt-transmission-repair-service/ Sat, 23 May 2026 18:48:05 +0000 I live near Detroit and I'm seeking a Trans rebuild service that does good work that might be near. I've got about 80K on the bike and at present have a broken shifter pawl spring. Makes since to do what's needed while it's open. Considering shipping it to Barrington motor works but wondering if there could be some other nearer options as well.

]]> My Airhead Needs Help Lee Nyboer https://www.airheads.org/community/my-airhead-needs-help/1981-r100rt-transmission-repair-service/ Hard Starting https://www.airheads.org/community/my-airhead-needs-help/hard-starting/ Sun, 10 May 2026 14:38:34 +0000 I am haveing a hell of time getting my 1985 R80RT started after having the carbs rebuilt and engine desmogged. Hopebully this video works and you can hear what is going on.  I have checked the valves and float bowls for debris.  I'm at a loss as to why it will eventually start, but starts so rough and hard.  Right now I really don't trust it for a longer ride.

 

https://drive.google.com/file/d/1RDN-RUHCeS_ln62M0uRFGCMtyQacfvjN/view?usp=sharing

]]> My Airhead Needs Help Curtis Nugent https://www.airheads.org/community/my-airhead-needs-help/hard-starting/ Centrifugal governor removal https://www.airheads.org/community/my-airhead-needs-help/centrifugal-governor-removal/ Thu, 07 May 2026 18:01:09 +0000 I wanted a project bike so I obtained my first airhead. 1977 R75/R. That's what all the documentation says and all the serial numbers agree. The front cover looks like it might have a 1975 or 76 ignition sensor, it has the centrifugal governor. Doesn't show that on the 1977 fiche I have been looking at. The cover has 3 holes instead of 2 also as stated on the fiche. Did BMW mix/match? Attached is a picture. Anyway, how do you remove it?

]]> My Airhead Needs Help Tim Cubbedge https://www.airheads.org/community/my-airhead-needs-help/centrifugal-governor-removal/ '74 r90s Idle Problem https://www.airheads.org/community/my-airhead-needs-help/74-r90s-idle-problem/ Wed, 29 Apr 2026 13:10:48 +0000 Looking for some guidance on my BMW R90S. I’ve been chasing an idle issue that seems to be getting more inconsistent, and I’m starting to wonder if I’ve got more than just a tuning problem.

Background:

Originally (before any clutch work), the bike was idling a bit low. I tried adjusting it, but had a hard time getting it to hold around ~1,000 RPM consistently. Once fully warmed up, I could sometimes get it close, but it would dip and stumble, and I’d see the generator light flicker like it wanted to stall. I often had to give it a little throttle to keep it alive.

Clutch repair:

I recently replaced the clutch cable. That’s now working great, no issues there.

After that, I thought I had the idle somewhat sorted around ~1,000 RPM.

New behavior:

On a recent ride, I noticed the idle climbing higher than expected, about 2000rpms. When I got back and put it on the center stand (still running), I tried to dial the idle back down, but:

  • The idle screws felt extremely touchy
  • Small adjustments made big changes
  • I couldn’t get it to settle consistently
  • I’m not confident I properly “reset” the idle screws from a true baseline

At this point, I’m not sure I’m correctly identifying when the idle screw is actually making contact internally vs just free play, so I may be chasing my tail there.

Current issue:

Right now, unless I keep the idle set relatively high, the bike wants to stall when I try to bring it down near ~1,000 RPM.

Additional observation (possibly related):

Yesterday, after running the bike and shutting it down, I put it on the center stand and realized I had left both petcocks on.

About 10 minutes later:

  • Left side looked normal
  • On the right side, I could see what looked like continuous fuel bubbling in the small glass area above the carb

I shut the petcocks off immediately.

Appreciate any guidance. I’m trying to be methodical here and not make things worse by guessing.

Keeping it real, if there were a spectrum of folks who are experienced and knowledgeable airhead mechanics, if it's not obvious, I'm pretty low on that spectrum. I have the original service manual as well as a copy of both a Clymer's and Hayne's manual. AI is a great resource for finding what I'm looking for as well. I came here, because on my clutch repair, some kind fellas helped me dial right into what needed to happen.

***Additional observation.....when I turn the throttle it does not snap back....it usually makes it's way back eventually, but not immediately and consistently. Sometimes I have to turn it back myself***

]]> My Airhead Needs Help Lance Mark https://www.airheads.org/community/my-airhead-needs-help/74-r90s-idle-problem/ Red charging light https://www.airheads.org/community/my-airhead-needs-help/red-charging-light/ Mon, 27 Apr 2026 13:01:53 +0000 1978 R100/7 : all components within the charging system are new and functioning correctly, strong battery, brushes/springs in good order, clean rotor surfaces, no loose wires up in the Speedo/tach housing, etc. etc.

The problem: the red charging light will go on, albeit a slight flicker on again/off again with the bike running at 3000 plus RPM. Not at lower RPM, just the mid-upper end of the tachometer range.

The light goes on when the key is turned on, goes out once the bike is started, as it should.

Problem existed before and after installing a Katdash for the bike.

Any thoughts?

]]> My Airhead Needs Help Anthony Fodero https://www.airheads.org/community/my-airhead-needs-help/red-charging-light/ Compression question https://www.airheads.org/community/my-airhead-needs-help/compression-question/ Sun, 12 Apr 2026 17:47:33 +0000 Hello, 

Ive been having trouble syncing my carbs. The left cylinder pulls way more vacuum than the other, so the manometer won’t level at all. The carbs were just rebuilt by Bing. I did a compression test and it was strange. I saw online to remove the carbs first before testing, so I did both:

with carbs on, no filter: L=65 R=120

without carbs on: L=130 R=125

what on earth is going on??

thanks!

]]> My Airhead Needs Help Blake Wester https://www.airheads.org/community/my-airhead-needs-help/compression-question/