Just bought a really nice, professionally rebuilt '76 BMW. Don't know much about them, never ridden one. Anybody with BMW motorcycle experience? 
BMW R75/6 Airhead
- Thread starter Passport1
- Start date
I read AV gas works best in the old ones.
I own two airheads, an '84 R100RT, and a '91 R100. I've previously had similar vintage ('75 and '76 /6 Series) R90S and R90/6 bikes. Been riding BMWs since '82, but not a mechanical wizard; I'm a reasonably well-informed owner.
Your bike has a couple of visible mods (aftermarket seat, /5 mufflers, and the later handlebar-mounted brake master cylinder), which aren't problematic, and the 750cc engines were the smoothest running engines among the several models, so, from what I can see in one photo, it looks like a reasonably nice example of a desirable "keeper" model. What are your questions?
Your bike has a couple of visible mods (aftermarket seat, /5 mufflers, and the later handlebar-mounted brake master cylinder), which aren't problematic, and the 750cc engines were the smoothest running engines among the several models, so, from what I can see in one photo, it looks like a reasonably nice example of a desirable "keeper" model. What are your questions?
Last edited:
Owned “Air Heads” from 1959! to 1981.
Most important thing I can advise you is to keep the output splines between the clutch and transmission lubricated. Not easy to do. You have to pull transmission back a bit and brush on grease. Some guys just removed transmission to do the job. These splines are a wear item.
Use Premium fuel, otherwise the bike will “Ping”. If it continues to ping, install thicker base gaskets, or two regular base gaskets under each cylinder.
Bing carburetors are easy to clean. You don’t even have to remove them. When it starts to run ratty, remove float bowl, get on your back and squirt carb cleaner into the two jets. You can also remove the tops of carbs and move jet needle up (richer) or down (leaner), by twisting needle and moving to the next groove.
The beauty of the /6 (or /5 or /7) was that you could fix or correct almost anything while on a trip.
Sold my last one (R65) in 1981 but still love those Beemer Airheads.
BTW. Beautiful Bike.
Most important thing I can advise you is to keep the output splines between the clutch and transmission lubricated. Not easy to do. You have to pull transmission back a bit and brush on grease. Some guys just removed transmission to do the job. These splines are a wear item.
Use Premium fuel, otherwise the bike will “Ping”. If it continues to ping, install thicker base gaskets, or two regular base gaskets under each cylinder.
Bing carburetors are easy to clean. You don’t even have to remove them. When it starts to run ratty, remove float bowl, get on your back and squirt carb cleaner into the two jets. You can also remove the tops of carbs and move jet needle up (richer) or down (leaner), by twisting needle and moving to the next groove.
The beauty of the /6 (or /5 or /7) was that you could fix or correct almost anything while on a trip.
Sold my last one (R65) in 1981 but still love those Beemer Airheads.
BTW. Beautiful Bike.
Señor khittner, very keen observations. Just a few general questions. I need to add some luggage capacity. The entire mounting frame and hard BMW cases are prohibitively expensive. Do universal soft travel bags fit well onto an old BMW? I've located a luggage rack on Ebay that would hold a top box but I don't know if it can mount to the bike independent of the entire luggage frame.
I was told that these models are reliable and require little maintenance. Is that your experience? I'm an old rider, not a bold rider so speed is not an issue.
tks
I was told that these models are reliable and require little maintenance. Is that your experience? I'm an old rider, not a bold rider so speed is not an issue.
tks
I see another one in background. Looking at the forks, it looks like an “S”.
Who does the restoration? Looks like he knows what he is doing
Who does the restoration? Looks like he knows what he is doing
A small shop in Wilmington, NC. Bombar's Beemers. Older guy, very BMW savvy.
This site is a wealth of information on every aspect of older AIRHEADS https://bmwmotorcycletech.info/technical-articles-list.htm
This is good also https://www.bmwmoa.org/default.aspx
This is good also https://www.bmwmoa.org/default.aspx
I didn't think I'd have an Airhead to see out my last years of riding, but I've had my '87 R65 for 12 years now, and doubt I will ever move away from it. When I first rode it I thought No Way, this is horrible, I just couldn't ride this thing. But I could see some potential, and bent it more towards my style of riding, and it's been perfect for me. There are certain things you have to do, but no more than any other bike of the same age....and the Airhead Gurus will make it sound complicated, and you will have to do this, and only use this and...and...and - and it's not as bad as they make it sound. Read Snowbum with a grain of salt, some real good info there, but he is more OCD than the worse OCD BITOG member. I've found the Airhead section of ADVrider the best place for Airheads - ADVrider did start off as a BMW site.
The difference between car drivers and bike riders can be different , but also the same. Car drivers will buy their choice of vehicle and either love and baby it, or ride it hard and hang it out wet .Just a vehicle to serve them. Bike riders can fall into the category's. The people that only ride less then 2k miles a year and like to keep it polished, to those who's only mode of transportation is their motorcycle. Those who put heavy miles per year on their bike ,want to know which tires last the longest, which oil tends to hold up the best in their model. Which brakes give the best service life and so on. Service intervals also play into the choice of ride. Nowadays most bikes have hydraulic lifters instead of adjustable ones, which saves time and $$$ if a shop works on your bike. Preventive maintenance is the key if you plan on doing 2-5k miles trips. Then you have the "I'll fix it when it breaks" kind of guys. I can tell you from experience nothing sucks more then having something fail or fall off on a trip, because you didn't take the time to put a wrench on most of the nuts or bolts when it was in your garage.,,,
Very true. I've been in both categories. Rode a 350 Honda to work almost everyday in Chicago even through the winter. Didn't have a car. Did two cross country trips just for the adventure. Now I ride a couple of times a month just to keep the bike limbered up. Doubt I'll ever go on another long trip.
I’ve never used soft bags on my bikes, so I'm not an expert in which of these works best for particular purposes, but your bike is short a couple of accessible anchor points for "throw-over" soft bags, because the aftermarket "king/queen" seat lacks the OEM passenger grab handle. But it may be a non-issue; there are probably soft bag attachment methods that can overcome this.
I’ve had a set of the OEM “touring cases” that I’ve transferred between several bikes for the last 25+ years. Secure, reasonably watertight storage big enough for a helmet, jacket, rainsuit, etc., that you can walk away from without much worry, and quickly detach/reattach for overnight stops, is pretty hard to beat. New sets of racks and cases are pricey, but decent used ones (and some clapped-out junk) can be found on Ebay, FB Marketplace, and the BMWMOA and Airheads BMW Club classifieds. There are several hard bag and mounting rack options, both OEM and aftermarket, and, if you decide to go this route, there are nuances about what hardware fits on which generation of bike that you need to be aware of before plunking down your cash.
As to "reliable and require little maintenance", your new-to-you bike is 45 years old---reliability can be had, but I wouldn't assume that most examples, including "professionally restored" ones, will have it. None of mine have ever left me stranded on the roadside, but I do have, and occasionally use, my old pickup truck to move them for service work when they "have issues" that are beyond my modest capabilities. A truck, or ready access to a trailer and a vehicle with a tow hitch, really is part of the airhead ridership deal. I don't think you should buy into the "common wisdom" claptrap that "those old Beemers are so simple--they're just like anvils, and you can fix anything that goes wrong right on the roadside!" The dealerships can still get a lot of the parts that you'll need, but most don't have techs that know their way around a pre-CANBUS machine, and they can do damage to airheads without intending to, and so many/most won't touch your bike. And you only need to briefly sample a couple of Bob "Snowbum" Fleischer's various and invaluable treatises on airhead maintenance and repair, to figure out that there are details to be aware of. You can learn to do some stuff yourself, and you're lucky to have some airhead service resources in your general neck of the woods---Bombar may be one of them (I know he's been around for quite awhile, but I have no personal experience with him); William Plam, in Hendersonville, is certainly another. Find the local/regional Airheads BMW Club for more resources and reviews.
And welcome to the airhead subculture! The motorcycles remain quite useful machines, and you have an example that'll need less work than many to keep nice.
Mercy I've read that stuff too but our knowledge about gasolines have
increased... the primary use of tetraethyl lead was knock or
detonation control but modern engines such as the BMW are engineer to
meet and exceed mileage expectations on lead free fuels... running
leaded AV fuel will not only drain your wallet needlessly but also add
yellowish lead deposits to your spark plugs and combustion chamber...
besides being a health risk lead is a high maintenance additive...
Thank you sir. I am a vintage rider with a vintage motorcycle and a vintage knowledge base. I appreciate your input.
All yes but…the R50/5 was far smoother than the 600 and 750cc BMWs. I put over 100,000 miles on examples of all three and the R 50 was like an electric engine. With so little reciprocating mass it had to run smooth. The R50/5 was not to common in the performance slanted USA but was a “third world” popular bike. It ran on regular gas and shared all parts with the bigger bikes that were not in the cylinder or head. I bought one in Houston with a HEALTHY discount as the dealer said he could only sell the big 750. $1200 out the door.
Oh, and oil of course. For 90% of riding conditions everyone uses 20-50...whatever floats your boat, but 20-50 is what is needed. Of course you can do other things - I am currently running Penrite 20-60...and have previously used mono grade SAE30, also a recommended oil for most riding temps.
I owned and wrenched a lot on a '72 R75/5 (swb) from '03 to '14. Lot's of info and parts sources out there on the web, but some is now gone. The "snowbum" Fleischer website and Duane Ausherman's site are very helpful. The Micapeak airhead mailing list used to very active, don't know about it now. BMW carries quite a bit for these old bikes, but not all. Motobins in UK is also a good parts source, but I can imagine that cross Atlantic shipping is crazy these days. The Airheads Beemer club (ABC) is worth joining and has tech days and rallies in some areas. After going through about everything on the bike, I regrettably sold it in '14. Also sold many parts afterwards. Took it from about 50k mi. to 94k mi. Did some touring with it.
Many, many fine points to need to know for working on these bikes, although they seem simple. Very few dealers won't mess it up.
20w50 for certain. Straight dino or blend if you must. At one time, the 20w50 oil that BMW sold was the excellent Spectro. That changed some years ago. Somewhat different filter set ups over the years. That must be gotten right or catastrophic failure. High octane for sure. Before they dropped the compression for emissions in the early 80's, they were made for 97 pump octane. The worst model for pinging was the R60/5-6. It had a bit more compression , but the milder camshaft didn't lower the dynamic compression as much as the R75-90-100 models with 308 cam did. Many of them got converted to dual plugs with an additional small peanut plug in each head.
Many, many fine points to need to know for working on these bikes, although they seem simple. Very few dealers won't mess it up.
20w50 for certain. Straight dino or blend if you must. At one time, the 20w50 oil that BMW sold was the excellent Spectro. That changed some years ago. Somewhat different filter set ups over the years. That must be gotten right or catastrophic failure. High octane for sure. Before they dropped the compression for emissions in the early 80's, they were made for 97 pump octane. The worst model for pinging was the R60/5-6. It had a bit more compression , but the milder camshaft didn't lower the dynamic compression as much as the R75-90-100 models with 308 cam did. Many of them got converted to dual plugs with an additional small peanut plug in each head.
Have had 2 BMW 750's. One was a /5 and second was a /7. Both very nice rides. Only problem was the fact that motor went completely quiet over 80mph. Cops just don't want to have you drive that speed. Keep up with rear swing arm grease. Loved mine but wife preferred my 1500 Gold Wing.
Similar threads
