92 k75rt rehabbing list

[lefthander]

Hello, I have purchased a non running 1992 K75rt that has not run in approximately 5 years. Bike has about 25,000 miles on it. Prior owner stated it just needs some mechanical tlc. I have a good battery that I'll use to check electronics. I am hoping someone can post a checklist on order of importance or of convenience to go thru the bike prior to startup. I will do a complete fluid renewal and spline lube for the final drive and driveshaft. I'm certain I'll be taking the tank inside parts out and see what's needed to be renewed along with a tank flush. I see where others have posted their similar experiences bringing a k back to life. I'm just looking for a step by step renewal order that may make more sense from experienced members. Thank you, John aka lefthander

[The Mighty Gryphon]

This is pretty much my routine when I get a "new" bike.  I'm sure there are others here who have a different approach, but this is what works for me.

Step  1: Get a bottle of S100 Motorcycle cleaner.  Most Harley dealers have it as well as a lot of other bike shops.  Remove the tank and the knee panels and do a good clean of the bike, wheels wiring and inside the fairing.  This will make all the rest of your work a lot cleaner.  It's also a LOT more pleasant working on a clean bike.

Step 2: Check all the rubber bits, especially the Z-tube Crankcase breather hose and the rubber caps that go on the throttle bodies.  Look inside the coolant filler for signs of mineral deposits.  Check the radiator fan for free spinning.  Check the brake pads for wear and order new ones if necessary.  Check the air filter and the air box for rodent condos.

Step 3: Service the fuel tank internals.  Clean out any old fuel deposits and the vibration damper goo if there is any.  Replace the fuel filter(NAPA Gold 3032) and the old internal fuel lines with SAE J30 R10.  Check that the fuel pump runs when power is applied to it.

Step 4: Get a can of Deoxit D5 and methodically go through every electrical connection with a light shot and working the connector on and off a couple times.  Don't forget the big plugs on the Jetronic box, the ignition control(ICU), and the ABS if you bike has it or the multi-switches on the handlebars.

Step 5: Fluid change.  Forks, brakes, engine, transmission, and final drive.

Step 6: Install the battery and check the electrical system; lights, horn, instrument cluster idiot lights.  Does the starter work?   

Step 7: With engine cold, check the valve clearances.  Adjust if necessary.  Install the fuel tank and start the engine.  Balance the throttle bodies when the engine is warmed up.

Step 8: Once you have the engine running you can drain the coolant and if needed do a system flush with distilled water and cooling system flush.  Refill with a 60:40 distilled water/coolant mix.  Any long life coolant will work. Run the engine for 5-10 minutes until the cooling fan comes on.  If it doesn't, it will need to be serviced.

Step 9: Adjust the clutch.  Service the brake pads if necessary.  Go through the bike checking all fasteners for proper torque.  Do final detailing on paintwork. 

Step 10: Ride.

[Rcgreaves]

Howdy Gryph,

Makes a guy wanna run out and find a project.  Well done. 

Sir, congrats on your find. 

[frankenduck]

http://www.kbikeparts.com/classickbikes.com/ckb.tech/0.ckb.tech.files/k75pa.rehab/k75parehab.htm

[beemuker]

http://www.kbikeparts.com/classickbikes.com/ckb.tech/0.ckb.tech.files/k75pa.rehab/k75parehab.htm

thanks for this. It may be useful as I get my "new" brick rehabbed. Still waiting for my injectors to be delivered to Mr Injector, so far 10 days but should get there today. It is across the country, but come on UPS.

[lefthander]

S-100 worked well cleaning under the tank, wheels, and inside the fairing. Getting ready to go through the electric connectors applying Deoxit and dielectric grease. I need to clean out the gas tank and not sure the best procedure with an aluminum tank. Is vinegar the best method? Is there a link I can get to do this correctly? Thanks for all the previous direction. Also I underestimated the length of time the bike was idol. Closer to 15-20 years.

[The Mighty Gryphon]

I have only had to clean one tank, and this is what I did. 

Remove the tank from the bike.  Remove the filler cap.

Remove the fuel pump, fuel pump mounting , filter and hoses. 

Put two gallons of white vinegar in the tank and let it soak over night.  Then dump out most of it and scrub the interior with a red Scotchbrite pad.  Wear nitrile gloves, the vinegar will marinade your hands.  Be very careful around the fuel level sender.  Rinse the interior well with clean water.

Soak up the water with paper towels and leave to finish air drying in the sun.

Put everything back together, replacing any damaged parts.  Get a new NAPA 3032 fuel filter and a foot of SAE J30 R10 fuel line to hook everything up.  DO NOT use the hose that came with the fuel filter.  It is not designed for use in the tank.

[lefthander]

Approximately 3 gallons of vinegar, three days of shaking, shifting and emptying and refilling. Final cleaning with scot h guard pads the thick brown  coating is gone. Very satisfied with the results. Thanks for the help Mighty G.

[lefthander]

Also, forgot to ask about seeing mineral deposits? in the cooling system. Mighty G., You have mentioned this earlier on another post regarding mineral particles. Would you not consider even starting the bike until system is flushed and new coolant added? Also saw you mention burping the fill hose neck and I remember doing this and it allowed more coolant into the system. This is in regards to my 92 k75rt that has sat for 7-10 years. I saw some floaters when I took of the filler cap. Can't say any were in the coolant reserve tank though.
Thanks

[The Mighty Gryphon]

No problem running the engine with minerals in the cooling system.  It just means that you don't have full cooling capacity. 

Fill the system with distilled water and cooling system flush and run the engine until it warms up an the fan runs.  Shut the engine down and drain the water and flushing compound,  Refill with distilled water only and run again until the fan runs.  Your system should now be flushed and you can refill it with a 60:40 water:coolant mix.

Now you're ready to go.

[lefthander]

While waiting for the fuel level sender item from  China I am going to lube the rear driveshaft and final drive splines. I am going to use loctite moly paste. Splines look good and I've cleaned them up well. While in the final drive spline cavity I came across a bit of brown oily substance. Not sure what it is. Hopefully the final drive gear oil isn't migrating in. Maybe moisture from the boot that goes on the swingarm to tranny. With the bike sitting as long as it has Im guessing anything is possible.

[Laitch]

I came across a bit of brown oily substance. Not sure what it is. Im guessing anything is possible.

It is residue created by oxidation in the presence of lubricant and water vapor—not uncommon in neglected Bricks. Just mop it up. Widespread use as a condiment wouldn't seem possible.

[lefthander]

That's a bit of a relief. Again, thanks Laitch.
So as I am getting closer to the day when I can push the starter, I am curious about all the internal fluids other than brake and fork oil.
 The engine oil thru the site glass looks pretty clean. The oil in the final drive as well looks fine. Is it acceptable to try starting the bike with these oils left inside? Not trying to be too prudent, but putting in all new tranny and engine oil along with a new filter without confirming that the bike will in fact start? I could use some insight on moving forward as I get closer to starting. What is the best approach at this point?

[lefthander]

Also just wanted to say the bike has sat idle for seven plus years. Thanks

[Laitch]

So as I am getting closer to the day when I can push the starter, . . .

All old oil develops compounds that lessen its lubricity. The oil should be replaced, the transmission fluid should be replaced, the rear drive fluid should be replaced. Take time to let all fluids drain completely because you can't warm up the engine yet to hasten the process. Be certain that all the filler plugs can be loosened before you remove drain plugs.

You should be completing all the steps that Mighty Gryphon has listed in Reply #1, including Step #8. Doing all that will keep the fuel injectors from being clogged by debris, and will significantly increase the chances of the engine's starting and running. You also will be less likely to return here with repeated questions about why it won't run right.

Be patient and thorough. Step #9 can wait.

[frankenduck]

I've brought many Ks that have sat for years back to life. For the first start I just make sure that the oil is topped off.

The only "precaution" I take is pulling the spark plugs and spraying some fogging oil into the cylinders so that they don't start out completely dry. Does that even matter? I don't know but it can't hurt.

Also, once you do put new oil in a K it will "go dark" in relatively few miles.

If you're just doing its first start and not riding it then there's no need to change the trans and FD oils.

[lefthander]

Thanks Duck,
 Ordered fogging oil as that sounds like a great idea.
 So I went ahead and lubed the rear splines along with the driveshaft splines. The main challenge there was retourqiing the final drive onto the swing arm. I have 3 different torque wrenches along with the wobbly fittings to fit the hex head bolts, but getting the hex head socket to sit into the bolt properly was a challenge.
 After that I ran into a challenge getting new brake pads installed.
 I tried pushing the caliper pistons out without any movement. With a pry bar placed between them finally got a little movement out of one side. Kept at it and after some time started moving more, however when I pushed out  one side the other side moved the same distance inwards. Looked for suggestions on this and couldn't find the fix.
 So, what I did was loosen the bleed bolts on the caliper with no change. I then loosened the bleed bolt on the abs fixture and Shazam, was able to push both pistons out with both bleed nipples loosened. There was a bit of fluid loss at both bleed nipples.
Finally able to reassemble caliper onto the rotor and reassemble the rear brake assembly. Maybe this will help someone else if they run into a similar situation.
 

[Laitch]

Did you remove the brake reservoir cap before you started that pad/piston-pushing odyssey, leftie? That seems to work for me. I also use speed bleeders; they just make the bleeding process less tedious and encourage me to replace fluid more often.

[lefthander]

 Its been a while since I've reported any updates on the 1992 k75rt I acquired awhile back. Ive added a new speedometer as the tripmeter wouldn't cooperate after opening it up and checking all the gears and so on. I came across one on ebay that actually reflected the true mileage within aprx. 200 miles. It was off a 92 k75rt as well. I purchased a new fuel level sender from EME and installed it. Works properly. So happy about that hurdle getting jumped. Also purchased the choke light pigtail and installed it. I like having the choke light because I can forget sometimes. Found a very nice Corbin seat at a great price that's in excellent condition. I've been trying to get the ABS to operate properly with resetting and cleaning all electrical connections, however the reset works for about 2 miles then the ABS lights start flashing again. I have purchased a new Odyssey battery and an led test light to see what code comes up. I have a battery in the bike now that, although fairly new is small that I had on my airhead. It starts the bike, but with the new Odyssey battery that should eliminate any doubt about enough power getting to the ABS system. I am liking this bike more and more. Once I get the ABS sorted it will be my long distance bike.
 I also found a real nice BMW oem tank bag with matching case liners as well as a liner for the rear trunk. Sorry for the long ramble, but I'm excited about this bikes potential and where it can take me. Thanks for reading,  Lefthander
 

[frankenduck]

If you have not done so already then check the routing of the wires from the ABS sensors. if not routed properly then those can rub against a tire and wear through the insulation.

[Past-my-Prime]

Also: I now have (or will soon have) a complete ABS replacement set: so if you have a bad sensor, or bad pump, or even bad brain, let me know.

I bought it as a backup for my (now properly functioning) ABS on my bike. I am aware that opinions differ on the utility of ABS and many riders will assert that they're better at stopping their bike than the ABS which may well be true in their cases but isn't in mine. I have experienced two occasions (one on loose gravel, another on wet leaves) where I braked hard to avoid a crash and probably would have crashed but for the ABS.

[frankenduck]

Also: I now have (or will soon have) a complete ABS replacement set: so if you have a bad sensor, or bad pump, or even bad brain, let me know.

I bought it as a backup for my (now properly functioning) ABS on my bike. I am aware that opinions differ on the utility of ABS and many riders will assert that they're better at stopping their bike than the ABS which may well be true in their cases but isn't in mine. I have experienced two occasions (one on loose gravel, another on wet leaves) where I braked hard to avoid a crash and probably would have crashed but for the ABS.

It's saved me a fairing or two. It also reduces insurance premiums.

[lefthander]

  Hey Past my Prime,
 I sent an message to you regarding your offer  for abs parts. Not sure it was sent your way, but I'm interested in your offer. My 92 k75rt has aprx. 25,000 miles on it. I purchased this bike about 6 months ago, got it running and like it a lot. The only issue I am having is with the ABS. I have done several resets. The abs reset works for around 1 mile then the blinking abs light starts up. I have used a led test light attached to the middle reset hole with the positive lead and the neg. to ground. It comes up as code? #7 which is a weak battery or the abs brain. I installed a new Odyssey battery to illiminate that as the issue. If I could test the brain by switching it out with a known good one to confirm its the brain that would be huge. I do want to retain the abs system.
 Another point is the abs relay. I have cleaned and used deoxit on the plug and relay itself. The abs switch does work as I was able to confirm that.
 If you happen to have an abs relay I could try along with the abs brain that would also be very helpful.
   Please let me know what you need from me. I'm in Savannah, GA. We can discuss shipping costs and what you would like to get for your ABS parts. 
  Thank you, Lefthander 

[Past-my-Prime]

I have yet to retrieve my “replacement bits” which I bought off of another denizen of this message board. I need to make a run to the border where the shipment is currently awaiting my attention. I suspect that the relay is not part of my list of goodies. But it may be! I’m being a bit proactive in buying items that may eventually croak, as my ABS is now working just fine.
I also have an old ABS brain that I couldn’t get myself to toss in the trash, possibly I could get it repaired by the gentleman in Japan who does these things?
Anyway, keep an eye out for the parts you want: there are enough people trashing old K75s and K100s in order to turn them into unique works of art, and who will sell the, to them, non-essential parts.
Best of luck!