R65 advice needed

[Fran Mach]

This weekend, 2/28, 2/29, I will be inspecting a 1979 R65 with about 40K miles, for purchase. The last time I owned a BMW was 45 years ago, a 53 R50. Can you give any advice as to what I should watch for in my inspection. A pic. of the bike is (hopefully) below. Thanks.

[schrader7032]

A few members have had R65s so they may have some specifics. But in general, I think you want to ask about maintenance records. Without riding it, I'd check the steering stem bearings to see that if you move the bars side to side across the center, do you feel any notchiness...that means bearings need replacing. If the bars can be moved very easily side to side, the bearings are too loose...if the bar movement is tough, then the bearings are too tight.

I see the carbs are what's called flat top Bings. They are OK carbs, but I've heard people have troubles getting them synched and tweaked...doable, but they were temperamental.

Look at the rubber boot that covers the end of the speedometer cable going into the transmission. If it is cracked or loose, then there's the possibility that water has going around the cable and into the transmission which could mean water in the oil. That eventually leads to trouble with the bearings. In the future, you would want to put a zip tie around the top of the boot...some actually fill the boot with heavy grease before installing.

Ask about gas mileage...should be something well in the 40s I would think. Also check the rubber bellows or fork gaiters in front. See if they're cracked. You might see if you can unclamp the bottom and use a small screwdriver (don't scratch the slider up) and see if any fork oil sneaks out...if so, then the fork seals will need replacing.

The bike looks to be OK from what I can see.

[Darryl.Richman]

People either like the R65 or hate it. It and its smaller R45 brother (which is identical except for only having 450cc displacement) were BMW's attempt to make an entry level boxer. Many parts do not cross over to the bigger bikes, even though it looks like they should. The bike is, however, lighter and shorter, so it has pretty nimble handling, and this can endear it to people.

(Compared to your R51 - the R50 didn't come out until 1956 - this bike should have almost double the power, way better brakes, way better handling and tons more cornering clearance. But it's also a lot taller at the seat. There's no kickstarter. It should get roughly the same 40mpg gas mileage.)

Still, they do not fetch a lot of money. I've seen very nicely turned out bikes go for $3-4k, but a bike like this with oxidized castings and some rust probably shouldn't sell for more than about $2k. Unless you're in it for the restoration work, you don't have a lot of "headroom" to fix things even if you get the bike cheaply.

I have an 81 R65 that I ride quite a bit. The 79 and 80 models have ATE brakes that don't have a lot of feel to them, although it looks like this bike has the upgrade to dual disks in front. They also still have points ignition, which is due for a service every 5k miles.

You should check the front forks carefully. While up on the centerstand and the handlebars straight, a small nudge should cause them to fall slowly to the side. If they clang, the steering head bearings are too loose, if they don't make it to the stop, they're too tight. Feel the bars turning slowly and carefully, any hint of a detent at the center point means the bearings are notched. Get on the bike and push forward while holding the front brake to compress the forks. They should compress and rebound smoothly and shouldn't stop at a different place than they started from. The brake fluid should be light amber; if it's nearly black, you're risking having to flush the whole system and there might be rust in the brake calipers. Also, look carefully in the tank and make sure that the red coating isn't flaking off and there's no rust apparent.

The bike should start easily; even if it has been sitting a while it should fire within about 3 seconds of pushing the button, with the throttle cracked only slightly and the "choke" on (it's a lever on the left side of the engine case). After the bike is warm and will run without the "choke", it should idle at about 1000-1100 rpm with the red generator light on, but this should go out at above about 1200rpm. If the oil light glows even dimly with the engine running, walk away at that point. The bike should idle evenly and sound the same on both sides. Don't whack the throttle open when it's cold and don't let it stand idling for more than a couple minutes, and if the current owner does this, look more carefully at each aspect of the bike.

If you can take it for a test ride, ride it at higher rpms in a lower gear to make sure the engine doesn't miss or run poorly above 4k rpms. (This is usually not expensive to fix: there's a rubber diaphragm in the carbs that can leak with age and limit how fast the engine runs, and if the points or condenser are bad, it can cause running problems at higher rpms.) If the bike rides well, take your hands just away from the bars and make sure that the bike has neutral handling, doesn't want to lean left or right. Try shifting into all 5 gears. BMWs are noted for their heavy, long throw and common clank, but shifting should be positive and it shouldn't pop out of gear.

If you buy the bike, never use the lock in the gas cap. It will fail eventually and leave you stuck. Also, put a zip-tie around each of the battery covers and the frame rail behind them so you don't lose them, which is a common experience with this model.

Good luck!

[Fran Mach]

Thanks for your advice gentlemen. Greatly appreciated.

[Mammagoose]

I can confirm that the gas cap lock will eventually fail. Left me stuck on empty for a couple of hours while trying to pry the thing open so I could fill up.

I also suggest zip ties around the carburetor float cups. The sliding metal clip can get caught on boot eyelets and get pulled away allowing for the cup to fall off. Already lost a couple of cups while traveling.

The rubber gasket at the base of speedometer and tachometer tends to harden and crack allowing water to seep in. Sometimes you can see humidity under the glass. It’s good to open them up. I found the PCB had oxidation on the components. I caught it on time and was able to clean it off. There should be a product to spray circuit boards to protect them from humidity. I small bag of silica beads helps too.

Water can enter into the gearbox from the tachometer cable. The rubber grommet gets old and lets water in. You’ll know it if changing gears gets stiff and when you drain the gearbox oil it comes out creamy. I fixed the stiffness by draining the gearbox oil then flushing with half liter of acetone and running through the gears with the motor running while on the center stand. Careful here. Don’t do this too long because you don’t want to give the acetone time to damage internal rubber seals. After 5 minutes max drain out the acetone and repeat with gasoline and oil mixture to rinse out residue acetone. Repeat a few times alway halving the amount of gasoline. Leave open for a couple of hours to let residual gasoline evaporate. Then fill up with the correct grade transmission oil. This worked for me and since resealing the tachometer grommet never had an issue again. There may be better ways to do this I’d be interested in knowing.

[cbclemmens]

I have to assume that you remove the rear wheel before running it through the gears on the center stand correct?

I think that isopropyl alcohol would be better than acetone. That will make water soluble in oil. And I would cleanup with penetrating oil rather than gasoline - much less flammable. Just a thought.

Craig

[srankin]

What is the price being asked? Pictures show a nice bike, for no more than $5000. The LS version would be a bit more valuable but not a lot.

R65 bikes have a bunch of devoted owners but, they don't fetch the bigger buck on resale as the bigger brothers. Forgive me if I insulted anyone with my $5000 price, but that is another argument for another forum.

As what to look for, most has been covered by others.

Is this an original paint bike? One big red flag for me is repainted bikes with low miles on the odometer. Yeah I get the previous owner may have wanted a custom paint job but, it also could mean the mileage is more than indicated.

At that mileage it SHOULD have the original tank lining intact. IF not, the lining is bad or relined, run away. St.

[spo123]

Unfortunately, the OP.....never returned.
This thread is also from 2015.

[srankin]

Well, I learned something today, look at the date, not just the fact the post popped up as new at the head of the line.

I feel silly answering now. No wonder there was no follow up. Not saying everyone follows up but this sure gives a good reason. St.