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85 k100 what did I do?

pjjj3386

New member
Took my brick for a quick ride today. 4 miles in stopped for gas and added about 6-7 ounces Seafoam, second time this year. About 8 miles into the ride wound the engine to about 6000 or 6500 rpm 2 or 3 time entering the highway. I've never reved it that high before. usually cruise between 3500-5000. Got to my destination, about 13-14 miles, parked bike on sidestand, and went into the store for a quick errand. ( lobsters $4.00/lb ). Got back to the bike and saw that something had dripped onto the rear tire, right side. Then noticed something dripping from the rear of the engine area. Said "Oh #$**". Figured it would be a good idea to get home. Rode home, tried to keep it between 3000-4000 rpm. Ran great! except alternator light started coming on. Just a slight glow, then it woud go out, the come on, etc. But ran fine. Got home, NO leaking. All fluid levels look good. Maybe a sign of something on the air filter cover, left side rear.

Sorry to be so long winded. Any thoughts?
 
I'm by no means an expert, but some of the questions they might ask would include:

1) Got any pictures of the leakage?
2) Is it oily, watery or something else?
3) What color, smell, etc can you associate with it?
4) Are all the normal fluid levels correct (engine, trans, final drive, brake fluid, coolant)

I'm sure there are many more that will come up, but those should help narrow down the source.

Monte
 
FYI - The slight glow of the alternator is probably due to a bad connection. My 85K100RT did it for a long time until I cleaned the central ground under the gas tank.

Also - Ignore #4 - missed the statement that all fluid levels look good.
 
Coolant from overflow bottle or hose,

Oil from rear of transmission.

Oil from rear shock.

Brake fluid from rear reservoir.

Milkshake from inside your tank bag.


Leaks flow down and to the rear. What is at the front top of the wet spot?



:dance:dance:dance
 
I think I know what the problem is. Follow the overflow hose back up to the tank. I will bet it is cracked where it attaches or disconnected altogether. When this happens, and it does, even to my well maintained machine, any overflow spills out on the air box and down the right side of the bike. Once you burn some gas down it stops over flowing.
 
I did not think it was gas, but I did fill a little more than I usually do.

And that will cause on over filled tank to vent fuel. Ask anyone who has removed the splash guard from the filler neck to get a few more ounces capacity. You will see the fuel coming out as they leave the station, especially under heavy throttle.
 
I think the answer has been found

And that will cause on over filled tank to vent fuel. Ask anyone who has removed the splash guard from the filler neck to get a few more ounces capacity. You will see the fuel coming out as they leave the station, especially under heavy throttle.

I have had the same thing happen. Ride it and keep an eye out for more fluid.
 
The fact that there is no sign of leakage now sort of points to something like gasoline, which will evaporate with very little sign that it was ever there..
 
The fact that there is no sign of leakage now sort of points to something like gasoline, which will evaporate with very little sign that it was ever there..

...well, maybe except for a slight yellow stain.

you put gas in. you found fluid leaking directly afterwards. you ran bike, using gas. no more leak.
yeah, you over filled it. no big deal. however, next time you have the tank off, check the condition of your fule lines and vent hoses. if origianl, i'm sure they need to be replaced.

now- what about that failure to use your engine issue? these bikes really like to run at high rpms. you are working at loading your piston crowns with carbon by never letting the bike "have its head". if you insist at always running at relatively low rpms, have fun down there, but at least give your bike a regular runup by bringing it into the 7k range.
when you need some fast power, that is the place you will find it.
 
Btw, please don't forget to check the overflow hose and it's connection to the fuel tank, underneath on the right side just above the air box. I will bet the hose is either disconnected or cracked. It's normal. When I put new hoses on the vent and the overflow, I use excess hose so when the hose gets hard and splits, I can cut off the split and slide a clean end onto the spout.

Yes, the K bike likes to be revved. This loads the engine, particularly the rings, cylinder walls and bearings the least, and thus the engine lives longer when you spin it. This isn't an old Stovebolt Six you could lug the living crap out of!
 
Update. Took it for a quick ride today, 10 - 15 miles. Tried to stay @ 4000-5000 rpm. Ran great. No leaks or glowing alt. light. Life is good.

Thanks to all!
 
Gas overfill: The gas expands in your tank if . . .

The gasoline expands in your tank if the bike is running or warm or hot.

The gas in the tank in the ground at the gas station is around 55 deg. F.

The tank on my 85 K100RS sometimes gets uncomfortably hot to touch which means its around 160 deg F. The fuel expands as its temperature increases, beware.

Added 9/20/12
Wiki Answers Goes like this: "Because gasoline expands and contracts based on temperature, the industry uses a standard temperature -- 60 degrees Fahrenheit -- as part of its definition of a gallon. To the industry, a gallon of gasoline is the amount of fuel that occupies 231 cubic inches at 60 degrees.
But at 75 degrees, the same amount of fuel occupies 233.4 cubic inches. At 90 degrees, the gas expands to 235.8 cubic inches.
Read more: http://wiki.answers.com/Q/How_much_does_gasoline_expand_with_temperature#ixzz270NZ2l"

So from 55 deg F in ground to 155 in hot tank, 5 gallons grows almost 75 cubic inches, over 1 liter (quart).
 
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I'm with Bikerfish

I am fully on the same page as Bikerfish1100......your bike needs to stretch it legs! Lets get some revs in the more often. It loves it once in a while, if not more often....:wow
 
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