BLOG – Page 14 – Airheads Beemer Club

Centerstand Repairs

Owners of early BMW twins are divided into two sorts; those whose centre stand bolts have failed and those whose bolts are going to fail soon. The root of the problem is that on the pre-square air filter models the stand pivots on bushes retained by a pair of bolts which screw directly into the frame. The continued heaving on and off the stand eventually loosens the bolts and the threads in the frame will start to fret. Retapping the frame to the standard thread (M10x1.25) and replacing the bolts delays the evil day, but when I found a bolt lying under the bike only days after doing this, I knew it was time to look for a better solution.

The remainder of this article is only available for Airheads Beemer Club members. Please login or purchase a membership here to join the Airheads Beemer Club, after which you will enjoy access this article and all members only content of the ABC web site.

Wheel Bearings

These procedures may seem complicated at first, but in reality it takes only minutes, once you have done it previously. MUCH of the information will not, perhaps, apply to YOUR motorcycle, but it all does need to be read, and understood.

BMW Airhead motorcycles are relatively tolerant to abuse and poor maintenance. Our human bodies are not tolerant to being dumped on the road at speed from a motorcycle. Of all the items that are safety related, the mechanically most important are the condition of the wheels, tires (tubes if any), brakes, wheel bearings. For non-mechanical, well, of sorts, one could add the importance of the rider’s clothing, and, in particular, the rider’s condition and competence/skill.

Discussion of ‘Tank Slappers’–Part 1

Discussion of Tank Slappers–Part 1 (Snowbum) Since the original publishing of the discussion about tank slappers”, I finished writing an extensive article on that and allied subjects. This was after accumulating a very large number of tests on a large number of BMW Airheads, mine, and customer’s bikes. The article is on my website. Here […]

Type V Fork Rebuild Tips

When I did research on rebuilding the forks on my 88 R100 RT, I found very little information regarding the “Type V” forks on the monoshock RT and RS’s. And, what little I found turned out to have a significant amount of incorrect information. I’m writing this to be used in companion with other information. Clymer indicates the wrong damper rod assembly for the Type V forks. In addition, the exploded views of the forks by both BMW and in the Clymer book are missing an O ring on the damper rod assembly. The BMW fiche indicates only one O ring located on the damper rod; however, there is an O ring on the valve, which is not shown. This O ring on the valve is the same O ring that is on the damper rod, so just double the order. Since I had a hard time trying to figure out what parts to order, I have included a parts list at the end of this article.

Throwout Bearing Maintenance

Sure… The reason I suggest doing this, is due to the nature of the layout of the rollers in the bearing. Before the ’74’s (/5 and earlier), BMW used a ball bearing throw-out assembly. They went back to this after 1984. If you referrence a price list, you will see that the ’74 to’84 roller set up is a LOT cheaper. The rollors are laid out radially in a circle.This insure that as the rollers attempt to roll, one end will go faster than the other and will scrape on the two “thrust pieces” on each side.

Flywheel Removal Warning

seal..etc., it is CRITICAL that the crankshaft be BLOCKED from moving forward. If you do NOT block the crankshaft, you run the risk of the crankshaft moving forward a small amount. This can result in a HIDDEN thrust washer moving downwards and off its two locating pegs. If that happens, the washer will not align back on those two pegs as you tighten the 5 flywheel (or clutch carrier) bolts, and you run the risk of MAJOR DAMAGE to the thrust washer….and even MAJOR damage to the engine casting. The crankshaft will begin to freeze up as you tighten those 5 bolts. There is another similar thrust washer located rearward of the engine casting, and it can also come off its pegs. I install it oiled, which acts like mild glue when installing the flywheel (clutch carrier) You REALLY do NOT want any of these problems happening. If you forgot or did not know about blocking the crankshaft, and you want to know IF the crankshaft has moved, there is a link near the end of this article, which will give you the information. The dimensions need to be as shown, in order to know that the crankshaft has not moved. The only way to see and get the hidden thrust washer back in place, if it has moved off the pegs,

Fuel system. Tank cleaning & protection. Premium vs. Regular. Fuel additives. Fitting other tanks/seats. Rusted/frozen seat hinge screws. Throttle & choke cables. Fuel hoses. Tank sealants/liners.

Tank cleaning & protection methods. Premium vs. regular. Fuel additives.
Fitting other tanks…seats & fitment with various tanks. Pesky
rusted/frozen screws on seat hinges. Throttle & choke cables.
FUEL HOSES. Tank sealants & liners.

No Spark on a /7

I have a ’78 R100/7. It’s my first BMW. It broke down a few weeks ago and I never got it started again. The problem is I have no spark. The local shop is no help unless you bring the bike in and I don’t trust them. I don’t think it would be a coil because there’s no spark on either side.

Double Row Timing Chains for Dummies

YOU CAN DO IT. You will want to replace everything. Don’t do a rinky dink job that will need to be redone sooner rather than later. Replace the chain $35, crankshaft nose bearing $10 and sprocket $65. Also replace the tensioner $10 and spring $2, and all gaskets and seals $17. These are 2003 prices. I got everything from Motobins and Eurotech. I found that the most worn piece was the crankshaft sprocket. The chain and bearing actually do not wear that much, but that sprocket is half the size of the cam sprocket and made of some soft stuff. The teeth get narrow and pointy. The gap between the teeth gets really wide as the sprocket wears. That’s where most of the slop in the old chain comes from.

Cylinders, case stud threads, heads, top-end, intake spigots, break-in procedures

If you are installing a camshaft and/or followers, READ http://bmwmotorcycletech.info/cams.htm regarding assembly pre-lubrication.

You may think that pulling off a jug is major surgery & frightening to contemplate. Once you do it, perhaps at a TechDay; or, from the information in this article, you should no longer have much apprehension about doing it yourself.

CAUTION-1: Every year comes questions about removing a head, perhaps for a simple de-coking (and not pushrod tube seals), & whether it is possible or not….to keep the cylinder sealed at the bottom. In order to do this, you would have to very securely wrap bungees …or via some other means, …around the cylinder fins, across the motor, & all-around the motor. Or some such. You would have to keep the cylinders from moving off the base area in the slightest. This method has been done when I only needed to work on the heads & was being done ‘in the field’, such as at a Rally, or a TechDay, & no O-rings and no piston ring compressor were on hand, etc. But, in order to do it, the bungees must be super-tight & evenly surrounding the cylinder, fore & aft. I recommend you not try it. Chances are high that you will not be fully successful & your cylinders will leak oil.

CAUTION-2: Never reuse a head gasket unless it is a real emergency. While it is possible to leave the two head-to-barrel nuts in place (the ones located at 12:00 and 6:00), & to reuse the gasket by never separating the head from the barrel, this is a poor idea. It MIGHT result in distortion of the assembly. I have not seen that distortion, if the assembly is done fairly quickly, within minutes. Pure speculation anyway. These 2 head nuts (located at 12:00 & 6:00) are supposed to be the first to be loosened, the last to be tightened (in the usual cross-staging).

The remainder of this article is only available for Airheads Beemer Club members. Please <a href=”https://www.airheads.org/my-account/?wcm_redirect_to=post&wcm_redirect_id=462″>login</a> or <a href=”https://www.airheads.org/product-category/memberships/”>purchase a membership here</a> to join the Airheads Beemer Club, after which you will enjoy access this article and all members only content of the ABC web site.

1 2 3 … 11 12 13 14 15

Posts navigation