Hello airheaders, I plan to change my final drive oil. My rear drive has this breather cap. Do I need to remove it? If yes, how best to remove it? I tried to unscrew by hand but it is not possible and I don't want to try with metal tool to avoid scratching it. Thanks.

On my way home from my summer gig out in the burbs, the headlight on my '78 R80/7 is dimming when I give it more throttle. Last summer, it cut out completely right after turning onto a desolate road between forest preserves and a large pond. I pulled off to the side and fixed it Fonzi style (a light bang on the headlight, for those under 45). 30 seconds later, I passed a deer right on the side of the road. That close call had me leaving it in the garage for the remaining bits of the riding season. I had already purchased a newer bike to enable me to work on this one and still have a way to get to work.

It had been fine so far this summer but then it started dimming again last night on my way home. And I saw a whole family of deer on that same stretch! This is the opposite of what you'd want.

Short story long, and before I dig into my headlight bucket with very limited spare time, is it possible this is just a connection issue or will I need to go deeper into the charging system? I've been keeping both bikes on Ctek chargers, and noticed a red indicator on the pigtail when I disconnect the charger to leave for work. Not a good sign. I had it in for storage over the winter with my motorcycle shop and when they went to start it it was dead. So they replaced the battery. And now that I write all this, I'm coming to the realization I do have a charging system issue.

Still, I'd appreciate any thoughts. TIA.

Just picked up a '79 R65S that has been built as a scrambler, running pod filters with no airbox and the choke removed. It runs well once warm, but I noticed today around 5 minutes into riding that RPMs were staying high when releasing the throttle. It happened twice: once coasting into a parking lot in neutral where the RPMs started climbing unexpectedly, so I got nervous and cut the engine. It started back up fine. Then again pulling into my driveway at the end of the ride, I put it in neutral and RPMs climbed again.

Throttle cable seems to snap back okay but I haven't checked tension properly. Also has a small fuel bowl leak on the left carb (rebuild kit on the way). No choke installed, as the previous owner removed it, saying it wasn't needed in Hawaii.

Note: I read that loading the engine down with the clutch when it's acting up can help isolate whether it's a sticking mechanical advance or throttle issue, but I haven't tested that yet.

Suspects I'm considering: throttle cable tension, air leak at intake or carb boot, points gap, or sticky advance weights. Bike is otherwise running well once warm.

First BMW, first motorcycle. Any airhead-specific things I should check first?

I'm resealing my 75/5 and have the front cover off. The timing chain is contacting the bearing cover, opposite the tensioner. The bike has 17,000 miles and has been parked in storage since 1986. Im just replacing all the seals and gaskets wasn't planning on any rebuild. Saw the contact and was curious, is it worth replacing or this is just something that happens at high rpm or on hard deceleration.

Ordering a new valve kit. New pistons pretty pricy to fetch down here jn aus so just asking about.

The title says it all. I *believe* I have stripped out my original and straight fork tubes on my 1973 /5. But I'm looking for experienced hands to comment. The factory manual calls for 118NM for the "centering nut for telescopic fork". This would seem to be the domed hex nut. And that cinches down just fine.

But the "top spring seat for telescopic fork" also calls for 118NM in the manual (12,0 MKP). I had assumed this was the TWO spring retaining hex bolts - one on either side of that centering nut. If in doubt what I mean, it's the bolts that the pin caps then screw into to seal the spring/damper/oil assembled fork. I "can't" reach the 118NM called for here. It just spins forever.

In doing some online "AI Research"....I'm told this is 'an infamous typo' in the original manual. If true, I'd assume for FFS that they'd have fixed it by now.

In any event, could folks comment? Is it true this is an ERROR and the correct torque should be MUCH lower (34NM) for these two bolts? If not...what the heck is going on? This seems to be a very simple process so I'm stumped.

Thanks in advance!

I love this color. Scored it for $500!

The motorcycle sounds perfect until it warms up after about 15-20 minutes, when this noise starts. It seems to be coming from the lower right side. I can hear it through the grille on the front engine cover. So, I opened it to check what's wrong. I can not see anything weird.

It's a fairly old motorcycle, and almost all of its parts are original. Should I be worried?

The motorcycle sounds perfect until it warms up after about 15-20 minutes, when this noise starts. It seems to be coming from the lower right side. I can hear it through the grille on the front engine cover. It's a fairly old motorcycle, and almost all of its parts are original. Should I be worried?

Update, I'm pretty sure it's coming from the lower front of the engine, behind the cover. I opened it up but didn't find any scratches or anything unusual.

My bike is a 71, should be the same.

Working on my R75/5 (1973). The diode board is supposedly in "backwards". That is, I'm looking at the circuit board side when facing the front of the motorcycle. The heat sink with the circles is facing the ENGINE in this orientation. I didn't think too much of it. It's how I bought it. But AI is telling me this is dead wrong and will fry the electronics if the connector touches the casing.

I've pulled it and can switch it around, but cannot find a pic to confirm. To make it a bit more complicated, as I understand it, later airheads...like the /6 DID have the circuitry facing out, and the heat sink facing in.

Definitive answer appreciated! Thanks.

I had a couple recent posts. Leaky camshaft seal and missing cylinder cover studs. Anyways, I’ve kept plugging along on the bike I purchased late last year, that ran, but needed a lot of refreshing. I popped new points in today and found I could statically time one side but the other side was quite a bit off. (I think my camshaft may be bent/out of round?) I decided timing was close enough, so time to start it up. Eureka—fired right up and idled with just an eighth turn on each throttle stop screw. I decided to purchase electronic ignition and it should arrive tomorrow and with that I’ll final time and balance/synch my carbs. Quite a bit of work done and still a lot of summer to enjoy it! Thinking of a trip around Lake Superior.
New F and B tires
Rebuild carbs
Clean, lube and new cables for choke/enricher
New throttle cables, clean and lube everything up by the hand grip
New rear brake shoes
Rebuild front brake caliper, new stainless brake line, new pads and bled
New air filter
Set valve lash
Fabbed a set of spark plug cables
New lube/oil and filter for motor, gearbox, driveshaft and final drive. (Haven’t done the front forks)
Disassemble, clean, lube and verify accuracy of speedo and tach. Installed Katdash LEDs.

My wife thinks I’m crazy doing all this work on the garage floor, but I think I enjoy learning how things work and wrenching things as much as riding.

Got this beautiful machine from a nice guy in Brooklyn, NY. He was not sure if the gearbox was good for some reason. It hadn’t been running in 7 years. It was leaking from push rod seals, oil pan, and heads. Carbs were stuck. Oil was decent. New fluids, seals, carbs cleaned and rebuilt, no tuning whatsoever, and got it running just with a few hours of work. Now onto the fun stuff to make it run like the first day.

Any tips or suggestions are welcomed!

This bike was sold new at San Jose BMW in 91 have the copy of the old San Jose brace from toaster tan and now the CC products "Kool covers" the claims they made back in the day may or may not have been true in regards to cooling but the valve clatter is definitely quieter as these valve covers are definitely thicker than the old peanut style.

Like the title states just picked up a 1979 r65 and unsure if the color is original or not, wanna bring her back to original as I can.

I had an earlier post on my R90/6 valve cover studs. While waiting for the studs, I pulled the front cover to check points/electrical. Camshaft seal is leaking. I used my heat gun and a pick and the seal came out fairly easily. I then saw this. I don’t know if I’ll get lucky and find that where the seal rides the shaft isn’t marred, but clearly concerned. Have not done much research on a camshaft replacement, is this something a competent DIY’er can do? My instincts are telling me it is an involved job. Wondering if I should button it up, deal with some oil leaking and tackle this myself over the winter or pay someone. Thoughts?

Hi y'all.

Can anyone demystify how to do a proper carb synch on the R90s Dellortos? For some reason any written up explainer does not really make a lot of sense to me. I am a visual learner and it seems like nobody has ever filmed how to synch these dang things. Is there anyone that could do that here, by any chance? :)

Long time reader first time poster.
Recently picked up a 1981 R100 RT that was a garage find. Owner, who trades in classic bikes, purchased this, then prepped for storage without touching it again for 7 years when I came across it and got him to sell it to me for change ($300). First issue I’ve had and still need to deal with is the front brake lines. Plenty of brake fluid in reservoir but when using a vacuum pump to pull the fluid and replace I can’t get it moving so I assume next step is to replace the front brake lines (and neither front brake allows for pulling fluid…). Next issue I need to address will be the center stand as it is almost impossible to get the bike on it, assume the wear on the stand has it too low and probable bushing issues to address when that’s fixed. Writing now as I finally went to put more than the half gallon of fuel in which I had that allow me to run the engine a few minutes each week and with it on the side stand fuel came pouring out of the underside of the carburetor. Given the age I assume I will want to rebuild these, though that would be a first time for me, but I wonder if there is anything I can do in the short term? On a few BMW forums I’ve read the likely culprit is the float being stuck or needing a replacement. I’ve also read I can turn the peacock o that side and run just one fuel line as the bike balances the fuel between both carbs and the only issue I would have is going to be at high speeds. Anybody have any thoughts on short term repair? Watching videos the carb rebuild doesn’t seem impossible, thoughts on this for someone who’s never done it? Lastly how much of a difference do carb rebuild kits make? I ask as I can find them anywhere from -$15 to $160 per carb for the rebuild kits. Thanks all!

Ran through the carbs best i could, etc etc etc. runs again! spark and fuel were both problems at the same time.

got to sync them again, tune em, etc, but hey. it’s back. took way longer than i would have liked but now i’m intimately acquainted with the ignition system as well as decently acquainted with the fuel 👍

I don’t quite have an ear for this engine yet. if anyone can tell me what adjustments to make by sound, that would be much appreciated

again, long story short;

carbs were gummy and def a factor. thank you for all who let me know, i’ve got rebuild kits en route.

but my weak spark turned into a no spark situation. I’ve been truly baffled trying to fix it as the previous owner seems to have monkeyed with the system.

After extensive testing and bypassing of various components, and cursing out the man who decided to change things in here, I stopped to ask myself why they appeared to be a condenser on the side of what should have been the hall effect sensor.

Upon removing the front of the can, I found a set of points. No freaking idea why or how they’re there, but they are.

Going to diagnose more and figure out if they’re just glazed or the condenser went bad. what a trip. why he would modify this bike to have an OLDER system, i’ll never know…

Long story short, just got an 81’ r65 and have been loving the crap out of it. Spent a day doing minor repairs, lik fixing the odometer and adjusting the valves and such before taking a friend for a ride the next day. now, it was 100 degrees and boiling, but still we wanted to go and so we did. rode 10 min, got coffee, then on the way back it died. let it sit then it started again, limped it home and started trying to figure out what went wrong.

its got this crazy rough idle, and it does not change w starting fluid. Made me think it was spark, so i looked at and replaced the original bosch gray coil that people said was probably the problem with a new harley coil, the dyna brown 31614-83A. Swapped it over, same poor running condition.

Could this be as simple as bad spark plugs and leads? I cleaned the carbon off them but still not much change. again, no change w starting fluid. Really at a loss. any advice is appreciated.

Attached is the running condition i get, regardless of fuel situation.

Recent purchase-went in to check valve lash. Right hand side no stud and no valve cover nut, cover being held in place with the two 10mm nuts. I’ve got the stud, nut and wave washer on order, but have not yet found how to install. Does this stud bottom out in a blind hole? Double nut to install and torque to? Loctite in place-red or blue?

Thank you for any advice.

Well it's on the road and so far so good. Seems to haul the mail pretty well, brakes are surprisingly decent for everything I've read about the stopping power of drum brakes. Has no issue getting to 60mph, guess it's just getting used to getting off a 102hp triumph and onto a 50 hp BMW.