As mentioned in another thread I've picked up an '86 K100, (think std). It's got a small (belly fairing?) headlight windscreen. And I'm trying to restore it. The bike has sat for the last 10 years in an apartment bldg garage in Berkeley, Ca.  As it literally had not been run for 10 years, the battery was not only dead it was petrified. And not wanting to spend more good money on it until I could convince myself it was worth the effort I picked up a used battery last night for USD $15.  An Odyssey PC680 if you're familiar with the brand. Anyway I charged the battery and today I changed all the fluids other than brake and fork oil. That comes tomorrow. I had already taken the tank apart and inspected the fuel pump and replaced the fuel filter this last week. There was a bit of crud in the tank which took some effort to remove. I seriously need to make a compressed air vacuum to clean out such things as tanks. Anyway holding my breath I started cranking the motor. I acknowledge as above I did take some cheap short cuts. I used a high grade synthetic oil which is 5-30 wt but cost only $24 for 10 quarts and a Thai made oil filter. But after a few minutes cranking it started up, a bit rough but idling at 1K rpm. The amount of smoke out the tail pipe was concerning but after idling for 20 minutes with a few throttle bumps, the smoke dissipated. I let it run for 30 minutes to check the various parts out. The oil pressure light is out, as is the gear indicator and the triangle light doesn't come on all the time as it should waiting for testing the brakes. The tach works but the speedometer is intermittent at best. After I shut it down, I removed the heat shield which was vibrating like all get out. Seems one of the screws attaching it to the exhaust had broken loose, leaving two small holes in the exhaust. Being a neat freak, after the bike had cooled, I got some gunk engine cleaner and sprayed everything I could get close to and then used a high pressure wash to remove as much of the filth as I could. Don't think the previous owner had cleaned it often when he was using it as a daily transportation. The amount of oil soaked dirt was the most I've every had to clean. The bike odometer shows 28K miles but the previous owner allows that it most likely has 50-65K miles. The speedo and odometer were out and he wasn't motivated to fix them.


Questions and request for comments, what would you suggest as a way to clean the aluminium bits. The gunk engine cleaner and pressure wash got rid of the top layer of dirt but the aluminium is still rather grubby looking. Any comments on whether to restore it to its original configuration or to try for something a little different. Like add a fairing. Would that make it more desirable? I've got 3 or 4 of the R100RT fairlings like in my photo that I could put on the bike as well as maybe a K100 fairing. Ten year old tires, any comments? They have plenty of rubber but are quite hard.

I'll continue to post as the project proceeds. Helpful comments are  always appreciated. Not sure if I intend to keep the bike or flip it. My pal that got me into this thought I needed another project to fend off the COVID blues. But I've had a K100 before and prefer the K75's as a bit more nimble. Anyway figure I should intend to break even or maybe make a couple of hundred if I do flip it.  The friend suggested that a price of USD $2,000. would be reasonable if the bike were restored to operating condition and the ugly bits fixed up.

Pressure washers are brutal on K bikes!  They blow shit and water into connectors and other places where it shouldn't be while blowing the sealant out of the places where it was used.  I like a good cleaner with lots of surfactants and a gentle rinse to clean things.  My favorite is S100 which you can get from a Hardly Dangerous motorcycle dealer.  Been using it for nearly 20 years.  I figure if Hardly guys use it, it has to be gentle and do a good job, and it does.  A quart spray bottle of S100 and a handful of bottle washing sponges on sticks from the dollar store will go a long way to cleaning the crap off your bike.

Pull the tank and seat off and use the S100 on all the wiring, loosening the dirt with an old 2" or bigger paint brush.  When I do my maintenance, I will take off as many parts as I can and give them a quick wash with the S100 before I start working on them.  The difference the S100 quickly makes in the way a part looks is amazing and is a great motivator for using it.

After I clean the black parts, before I put them back on the bike, I'll give them a bit of a rub and buff with Mother's Back to Black restorer.  It cleans up fading and sun damaged black plastic, rubber and powder coated parts quite nicely without too much work.  The really bad stuff might need another shot to really get them nice.

Last, Zymol cleaner/wax from Walmart is very good on painted parts to protect and bring out the color.  Very easy to apply and it holds up pretty well.

A can of Deoxit D5 spray is good for cleaning connectors and handlebar switches and will head off the strange electrical problems an idle bike can have.

Point-Seven-five wrote:Pressure washers are brutal on K bikes!  They blow shit and water into connectors and other places where it shouldn't be while blowing the sealant out of the places where it was used.

Whooo! after reading that I ran outside and restarted the bike. It did crank a bit longer than I like but started up though a bit rough. In changing the anti-freeze I had rocked it and probably got a bit of oil into the cylinders. The first K bikes had a problem with oil seeping past the rings when on the side stand.  I'll look at your other suggestions though I've never really been a fan of S100. Seemed to me to be an overpriced detergent doing the same work as simple green.

At this point though it is raining locally. The Democrats haven't yet gotten the weather properly under control here in Calif. And so I won't be able to get into the brakes and fork lubes for a bit. My thought is to get the bike runnable - still waiting for DMV to issue tags - and then start the restoration proper. The frame is a mess with surface rust and various parts also rusty. Think I'll start with the instrument pod replacing bad bulbs and making electrical connections tight.

If you have been vigorous using a pressure washer expect problems as a result. Clutch pivot boot, ingestion through the gearbox vent, possible issues on the gear position indicator switch behind the swing arm.

throw those tyres away , rubber ages with time and becomes like plastic , and an old tyre on a cold morning is literally like riding with plastic tyres , i know this from experience, i learnt the hard way , lol   . tyres all have a date code on them for this reason , even though they can look good its the age that is critical to grip . for cars they actually age the tyre to make it harder and then it lasts longer , for motorcycles we want them fresh soft and sticky

Here's my slacker's tip for keeping a clean bike: once it's clean just spray it all over with Armorall protectant - paintwork, plastics, metalwork, 'lectrics, brake calipers...the lot. Okay not the tyres, and do wipe the discs with brake cleaner afterwards. Let it dry by itself, and you can polish the shiny bits later if you're feeling a bit of bike love. This stuff seems to stop the dirt sticking so much, so the bike is really easy to clean, which means (for me anyway) that I don't put off cleaning it so much. Keeps corrosion at bay for years even during our salty UK winters.