85 K100RS Found a sheared RIVET in my oil: 178,951 mi. Will post pics of the repair.

[075038]

Updated After Repair: Rode to the Billings WY rally and back to Phila. without incident, changed oil (hot) and found a sheared rivet in the pan. It was a great and problem less trip of 6,500 miles. I had been told that 1985 models have only 6 rivets in the "bull" "absorber" "output shaft" gear. Some fail by 120K mi.

I'm buying replacement and upgrade parts and will take off the intermediate housing again this year (starter sprag in the spring) and drop the bottom case section and output shaft. My list of "better do while you have it apart" includes rear main seal, both o=rings on each injector, Trans. input seal, clutch pivot brg. and boot, spline lubes, change the oil and filter, lower rad. hoses, thermostat, and it's growing.

I've been advised to finally get a lift and now have a big red H. Freight one from craigslist with a modified front tire "ramp." The center stand now misses the drop out rear wheel panel and the ft. tire sits right in the clamp when it rolls back onto the center stand.

 

[35634]

Might consider sending the injectors to http://www.mrinjectorparts.com/ to get rebuilt $17ea. And they put on new o-rings.

 

[98lee]

Might consider sending the injectors to http://www.mrinjectorparts.com/ to get rebuilt $17ea. And they put on new o-rings.

And turn around time is usually about one day.

 

[075038]

Original Poster (OP) : After working much of three days, a new 12 rivet Absorber (Bull) Gear is in my 85 K100RS motorcycle. The old gear was missing half a rivet that I had found in the waste engine oil. The third day included returning the clutch, trans, swing arm, water/oil pump, starter, alternator etc. By noon the middle day, I was glad to have about 150 (photo with screws in egg crates, the order precludes needing a notebook too)
30year old screws out without breaking or stripping one. My biggest trick is grinding high quality Allen wrenches and 3/8" socket drive Allens to be very blunt, not cheap, old and rounded and digging out the dirty recesses with a dental pick sometimes.

I reused the big absorber gear bearing and got it off by tapping a screwdriver in slightly, around and around. I had a hard time rotating the new thin gear against the spring to get the mating gear's pin to fall in. I used strong hands and twisting the blade of wide screwdriver. Later, the directions said to use a shim this time just under the big bearing, so I bought the four sizes. I needed one thinner than the thinnest, directions say to emery it down to be thinner. Well at least 15 minutes on 220 grit took it from .062" to about .060." I'm counting on the thin gear going a little concave because the shim should have been ground down to .055" to have the .003" of clearance they wanted. Besides the new shim design, the e-ring that takes the bull gear thrust load now has tabs around its perimeter. I used large vise grips to pinch these tabs so the e ring would go all the way into its groove.

Having replaced the sprag starter clutch last year and upgraded the water/oil pump 7 years ago, I'm now in familiar territory. This time I've also replaced the thermostat, the water hose that goes through the engine case, a magnetic oil drain plug, a rear brake lense, left turn signal thumb button, new rear main seal, fluids, oil filter and maybe a trans shaft seal or two. It would have been simple to do the oil level sight glass but I did that a few years ago by punching it out from inside the oil filter hole.

Preparation included paying a terrific dealer for an hour of their super K bike mechanic's time. I left with a good list of short cuts, parts, sealants and Loctites to buy. He also said buy a lift, so I found a Harbor Freight one on Craigslist and bought it. The bike with the motor still in it also hangs from two I-beam clamps with ratchet straps over the lift.

The third day included mounting a new Michelin Pilot Road III with a new K1100 three spoke rear wheel and a new tank bag and new rear lense and with new bulbs, filling the tires, oil and water and going on a 50 mile test drive. I took a photo of the tools I used.

It seems to run great and idle very well, haven't gone past 5K RPMs though. Update March 13th: Ridden about 150 miles, very happy with it. Couple things nagging at me: Wonder if too much sealer is near the shaft's needle bearing "cover groove." It might be part of an oil flow situation to a hole that feeds the needle bearing, but the flat surface right next to it on both sides needs sealing. Didn't want to overfill the oil so I put in 3+ quarts, saw some oil at the bottom of the glass and ran the first 50 miles, have since brought it up just over the center dot by adding 1/2 a quart or so. I've washed it, waxed it, Simple Greened the bare aluminum around the bottom, checked for weaps, shoe polished the black leather seat, put wood shims covered w black elec. tape between the saddle bag hook mounts and the saddle bags, fixed the spoiler mount, and put it back on. I did the job without stopping to order more parts and waiting for them, Ahh.

Future plans include putting on some parts I have: 8 injector O rings, 4 rubber pipes that connect the air box to the throttle bodies and tweak the 3mm hex adjustment to run a little richer, as the alcohol in the gas needs more fluid flow for the same amount of air. (During the ride to Billings and back, I noticed it ran better at a steady 75 mph when either I had filled it with 0% alcohol gas or I rolled on the throttle the slightest bit, but at dead steady throttle it was not as smooth, just a little too lean, I think).

 

[8ninety8]

So respect the way you dive into that engine. Nice work. Thanx for the heads up. Cheers.

 

[58058D]

Love your egg carton inventory system. Each spot numbered and, I assume, catalogued in your notebook as to what each item is. Great stuff!