Generic Airhead questions

[ultracyclist]

Are the airheads easier to work on because they are carburated, have only 2 valves/cyl, and in general smaller displacement engines?

My current rad is an '02R1150R, but I love the looks and ergo's of the R100RT.

Where do the dedicated airhead owners find parts?

[20774]

I would say the motto "simple by design" more or less answers the question. But you're probably right, everything is right there, exposed so it is easier to work on and trouble shoot.

As for parts, there are plenty of sources, including even your dealer!! Other places like Bob's BMW, EuroTech, Motobins, Hucky's, etal. Vech at Benchmark Works tends to specialize in the /2 era, but he's expanding his line to /5 and beyond. Another outfit, Boxerworks, has been getting good reviews. There are specialty places like Rocky Point Cycle and Motorrad Electrik that can provide electrical parts. There's also several used part places if there's a need to go that route.

Just like anything newer, cars, trucks, etc., it gets harder and harder for the average mechanic to do much these days.

Kurt in S.A.

[Isamemon]

Ill go with Kurt
simple is better
Ive had plenty of bikes, asian, that I could not work on the carbs without a 2 hour headache
but, to their credit, when the do break, they are ofeten cheaper
I wish I could do a clutch as cheap and easy as a same year honda, not gonna happen
as far as comparing price to a newer BMW, no idea
but for me, I look, fuel infection, sencors to tell you that you have your sidestand down,computers
good luck on a back road, middle of nowhere, and the fuel injector brain decides to go to lunch
if I have points and a carb, Ill get home

so who did I piss off today ????

[jdiaz]

Are the airheads easier to work on because they are carburated, have only 2 valves/cyl, and in general smaller displacement engines?

My current rad is an '02R1150R, but I love the looks and ergo's of the R100RT.

I thought the Oilhead was the easiest bike to work on, period. The K isn't bad, but needing to change shims or buckets in the valvetrain is a pain.

The Airhead isn't easier to work on IMO. Its easy, but not easier than the Oilhead.

[The_Veg]

I've never owned an Oilhead, but I hear that there's a lot less to do with them.
With an Airhead be prepared for lots of valve adjustment, rebuilding carbs every few years and tuning them every few weeks or months, more spline-lubes (most Airheads do not have the hardened plines like later bikes), more ignition maintenance, brake adjustments (bikes with A.T.E. brakes only) etc. None of it is difficult to do, but it is more stuff to be done.
I should point out though that the later the bike, the less there is to do. I have a 1995 R100R and it has the hardened splines so less lubing there, and because it has a Paralever rear-end I don't have to worry about driveshaft oil. It also has electronic ignition so no points to worry about. Better yet, it has the best valve seats of the whole Airhead line and I've had to do only very minimal adjustment in the 26K miles I've owned the bike (which has 58K total). There is also only one hydraulic line on the whole bike (it feeds both front calipers and the rear is a cable-actuated drum), so that's fewer lines to worry about.
So how much do want to work on it?

[sgborgstrom]

I believe some people think the airheads are "easier" because just about everything on them is mechanical. The newer bikes have more of those mysterious black boxes with multi-colored wires leading in and out, effectively posting a big "NO user servicable parts inside" sign on the bike.

The old twins have charisma in abundance, a look and feel more modern bikes don't have. In exchange you get a lot more things to tinker with on a regular basis. Some of us think that's fun, others don't. In the modern era, for the average rider I think the airheads are great Sunday morning ride bikes, one good oil change and tune-up a year. But they don't have that appliance-like turn it on and go simplicity of ownership most current BMWs have that allows you to rack up 20K a year without thinking too much about it.

Steve

[jdiaz]

But they don't have that appliance-like turn it on and go simplicity of ownership most current BMWs have that allows you to rack up 20K a year without thinking too much about it.

Now that's an impressive sentence. :laugh

[kbasa]

I thought the Oilhead was the easiest bike to work on, period. The K isn't bad, but needing to change shims or buckets in the valvetrain is a pain.

The Airhead isn't easier to work on IMO. Its easy, but not easier than the Oilhead.

Same here.

[sgborgstrom]

Now that's an impressive sentence. :laugh

Yeah, BMWNA ought to pay me by the word.

Steve

[ridewv]

(most Airheads do not have the hardened plines like later bikes)

When did BMW start hardening the splines?

Thanks,
Rick
1991 K100RS
1993 R100R

[Isamemon]

I am one of those old farts where simple is best
but you guys are giving me the impression that the oilhead is an easier bike to work on
is that true for the old guy in the garage, or the guy way back on a back road , where cell phones dont work, and something craps out
if I have gas and spark, Im good to go
what would be better........a diesel
after you get them fired up, good to go, dont shut it off

and then I look at oil heads, and yes I would like better brakes, but people at that thread are asking, what an we do with ABS

and ABS brake problems, say what
ABS means avoid braking situations, so whats the prob
you got ito that on your own

but this old airhead, so simple to work on, so straight forward and accessible
pulling apart a couple of bings ( like old su's) i would rathr do then get the electrical tester out and try to figure out, if the fuel infection is working
Ive said this a bunch of times
this is my first BMW, and I love it, 78 r-80
not trying to offend, just trying to learn

and so since I am happy with the power, what woudl give me better brakes, less diving in corners, and easy side of the road tool bag maintainance
just asking, not trying to offend, opinions please .................

[Isamemon]

ok
rip me a new one folks
I am so used to it
so how come , when I go to the oil head forum pics
they look nice, but have etihr front fenders that look like harleys
or have some kind of big bird scoop under the headlight
ohhhhhh Im in trouble now
nothing new for me,
just ask my wife
...................
love my airhead
yes love my wife toooooooooo

[AntonLargiader]

and so since I am happy with the power, what woudl give me better brakes, less diving in corners, and easy side of the road tool bag maintainance
An Oilhead.

[robsryder]

Are the airheads easier to work on...?
Where do the dedicated airhead owners find parts?

I have a 94 R1100RS oilhead, purchased new. I also have a 93 GS/PD, purchased barely used. Both of these bikes are about equivalent to work on. In the case of these bikes, "work on" generally means performing routine maintenance activities. I tend to do this routine maintenance at a somewhat higher frequency than proscribed by BMW.

For my older airheads more work is involved.

The additional work is due to my having purchased the older bikes at nearly an order of magnitude lower cost than the oilhead. Plus I was specifically looking for "project" bikes.

My 1977 RS had nearly every fastener and part "touched" by me over the last few years. Since my "touching" I would regard this bike as being nearly as easy to work on as the newer bikes.

I guess that it depends on your starting point (i.e., having a new bike vs a project bike) and the degree to which early issues are identified and corrected (largely the point of routine maintenance and inspection).

Regarding parts sources - I am fortunate in living near Re-Psycle BMW (as well as two BMW dealerships). Re-Psycle always seems to have what I need in stock. Re-Psycle is not the least expensive source for parts.

I have also purchased used stuff from Airhead Cycle Salvage and a variety of items (new) from Bob's BMW. Parts availability has never been an issue.

I also have an old Honda (65 Superhawk) that I'm going thru. It is a much greater challenge to find needed parts (at reasonable prices) for the Honda.

[PeoriaMac]

"On the other hand, the old Airheads can carry a real load".

Alternative caption: "There were enough of the police spec bikes to go around..."

[tuber1]

rack up 20k a year....well, Jim Klas and 'Mac' Mchugh ,plus many others managed to rack up way more than 20k a year on airheads, and we never had cell phones, or gps, lol ,none of that fancy cool stuff...

[28796]

When did BMW start hardening the splines?

Thanks,
Rick
1991 K100RS
1993 R100R

The tranny/clutch splines are still failing on Oilheads through 2004 so it hadn't been fixed by then. No idea how the new 1200s are holding up. As far as maintenamce & reliability goes I don't think the Oilheads fare very well when compared to other modern bikes. There are way to many issues suchs as spline failure, ABS modules failing, rear main seals hosing all over the clutch, Paralever bearings, regular throttle body synchs, 6k valve adjustments, mediocre trannys & much more.

[jdiaz]

As far as maintenamce & reliability goes I don't think the Oilheads fare very well when compared to other modern bikes. There are way to many issues suchs as spline failure, ABS modules failing, rear main seals hosing all over the clutch, Paralever bearings, regular throttle body synchs, 6k valve adjustments, mediocre trannys & much more.
You forgot bad master cylinders, soft wheels, throttle body rattle, and leaky oil pressure sending units on the early RS models.

Rear main seals have never been an issue. 1996 and 1997 models had a problem with a scratched intput shaft gouging a seal which would allow gear oil to migrate to the clutch plate.

[28796]

Rear main seals have never been an issue. 1996 and 1997 models had a problem with a scratched intput shaft gouging a seal which would allow gear oil to migrate to the clutch plate.

Really! Tell that to the guys on the R11S list that have tossed oily clutch discs.

[James.A]

It is my considered opinion that BMW spent 9 years(1970 to 1979) building motorcycles that were simple, user friendly, and highly reliable. (early 5 speeds being a stain) To my mind, these are the bikes that made BMW's reputation and are the bikes against which all others should be judged. They have now spent the next 27 years drifting away from that ethic.

[ultracyclist]

Assuming that one did not ride an airhead ridiculously hard, what kind of fuel economy could the airheads get?

[manicmechanic]

My first Airhead ('84 R100RT) would routinely get 48+ mpg.
The '76 R90/6 with Hannigan fairing averages about 40ish. Push it past 75mph and that drops to the mid-30's.

[James.A]

My R75/5's get 41MPG, on average, regardless of how hard I ride 'em.

[James.A]

Assuming that one did not ride an airhead ridiculously hard, what kind of fuel economy could the airheads get?

A well tuned and properly serviced airhead can be ridden to the limits of its ability, relentlessly. They are the only motorcycles that are over-engineered to the point of being bullet-proof.

[cjack]

It is my considered opinion that BMW spent 9 years(1970 to 1979) building motorcycles that were simple, user friendly, and highly reliable. (early 5 speeds being a stain) To my mind, these are the bikes that made BMW's reputation and are the bikes against which all others should be judged. They have now spent the next 27 years drifting away from that ethic.

I'm trying to think back. We started to see transmission bearings go bad in the early '70s, clutch splines go out in about '74, rear engine seals leaking (and squawking), you mentioned the spring in the transmission or also the complete change of transmissions in the early '74 at the warehouse, the dreaded notched steering head bearing at early mileage, oil consumption in the late '70s (remember the three piece rings?), lots of broken spokes, cracked cast rims, thousands of leaky oil pressure senders (do they leak on cars?), broken rear sub frames (folks carried a piece of angle iron and a couple of hose clamps), and of course the rotor and the diode board. The thing about this is that most of these failures would not leave you by the side of the road. And the repairs didn't take 14 mechanic hours to gut the bike and rebuild it. That is something the new K12 bikes seem to be designed well against. They look easy to get to repair and maintain. I'm hoping...

[jdiaz]

Really! Tell that to the guys on the R11S list that have tossed oily clutch discs.
I apologise. There were 200? 500? bikes out of 500,000 Oilheads built that had a problem with main seals. :)

That failure rate is less than the number of dead K1200LT final drives, unfortunately. :cry

[Rod Sheridan]

My 1976 R90/6, unfaired, had a fuel usage of 4.63l/100Km on the 800 mile return trip to Vermont last month. (60.3MPG). This is average consumption, some inter-state type roads, a lot through the Adirondacks on secondary roads.

Regards, Rod.

[ultracyclist]

Here is the $64 question:

If you you could design the perfect airhead, what engine would you choose? tranny? simplicity?, parts availablility? et al?

Now, what production bike comes the closest to your parameters so crazies like me may consider it in starting a new hobby?

Btw, do the airheads surge like the oilheads?

[Braddog]

I dunno, I think a well-sorted R75/5 is about as good as it gets, in stock form, anyway. I had a good friend that had well over 200K with NO major issues other than regular maintenance.

Geared right, a 5 speed is enough. My RS has higher gearing than stock, which is nice.

Parts availability isn't an issue...at least not yet.

Airheads don't surge because they're carburetted. Surging is a fuel injection issue.

[James.A]

Yeah,Brad, I'd go with the R75/5 with the 4 speed but I would fit it with /6 rocker arm assemblies. And maybe I'd look into a dual disc front brake set up with a handlebar master cylinder and all the appropriate up-grades. I don't think the single disc is much of an improvement over a well maintained drum front. I have a set of /6 heads ready to go when one of my /5's becomes needful. I may have to scout around for parts to dual disc the front of my designated commuter bike. I could use a minor project for the winter.

[Isamemon]

some have mentioned the trany and gearing
one thing, that has taken me a while to get used to is the ratio difference ( or lack of ) between 4th and 5th
there is an obvious difference between 1&2, 2&3, 3&4, but it ends there
its , did I shift ?
I think, in the oldend days with the airheads, they could have easily put a bit larger ratio difference, and seen a good improvement in MPG
Im still getting used to riding a airhead, after years of rice rockets, and I keep looking for another gear
Id love to drop my r-80 a few hundred rpm at 70mph
oh thats right , yes dear, I only ride the speed limit

[James.A]

I put a 5 speed from a 1974 R90/6 in my cummuter bike. The other one is stock. (R75/5's) The difference at the top is that the 5 speed allows me to achieve 100MPH by the speedo where the 4 speed runs out of push at 90. Same final drive on both bikes. And, the commuter bike has higher mileage. 80K

[AntonLargiader]

The difference at the top is that the 5 speed allows me to achieve 100MPH by the speedo where the 4 speed runs out of push at 90.
Well, top gear in each is basically the same ratio, so you need to look elsewhere for the cause.

[James.A]

Maybe it's speedometer related. Fortunately, I have thus far avoided radar clocking at those speeds. Bottom line, in my situation, the bike with the 5 speed tops out higher according to the speedo. Having said that, I like the 4 speed better.

[28796]

Here is the $64 question:

If you you could design the perfect airhead, what engine would you choose? tranny? simplicity?, parts availablility? et al?

Now, what production bike comes the closest to your parameters so crazies like me may consider it in starting a new hobby?

Btw, do the airheads surge like the oilheads?

While I love my LWB R75/5 which is stock except for electrical upgrades & a pair of Mikunis my 87 R80/100 project is as close to Airhead perfection as I've gotten so far.

Start with a monoshock R80/R100(85-92), bump the compression/displacement(if R80), install slide carbs, taller gearing(if r80), upgrade the electrical/ignition system(all Airheads), stainless lines/modern brake pads & then modify the cosmetics to your tastes.

[plexiform]

I have an 88 R100/monoshock...planning to do just as John has stated. Just getting started right now. Biggest problem I'm finding is how to actually have the mechanical changes to the engine done. I'm somewhat mechanically inclined but not nearly enough to take the engine apart. I imagine it may take many labor hours to achieve the changes John talks about. I'll give you an estimate as to the cost of a STOCK to "PERFECT" conversion when I have a better idea of what is going to go into the bike with respect to labor. It appears that the parts for the conversion alone will be around $800 for the compression and cylinder upgrade, and another $200-400 for the carbs depending on where you get them. Another $400-800 to upgrade the exhaust to stainless depending on manufacturer. And labor costs will also only be an estimate since sometimes things work the first time, and the remaining 99% of the time things get done and redone to achieve 'perfection.'

[paulfinney2]

I've got an 86 R80RT which I am very happy with [also a 76 R75/6 that I am reviving]. I understand BMW started hardening the splines in '85. But I am pleased with the brakes, electrics, and on the recent trip to MOA Rally and Nova Scotia, got as good as 55 mpg, low 50's consistently.
Now I just have to straighten out my front forks, after meeting a Ford Taurus wagon who had better brakes than I did.