'81? Kawasaki KE175 running problem

[CRXSi90]

The bike has sit for most of the time I've had it because it never really ran quite right. The bottom end has always been dead as a rock...I have to rev it up to about 3-4k and/or very slowly let out the clutch for it to even go without dying. Once it gets going, however, watch out! I can pull wheelies on this thing easily, at least in first gear (never attempted any more). I just adjusted the float and raised the fuel level, and it seems like it didn't help the bottem end problem (I thought the fuel might not have been getting to the pilot jet which is set a little higher than the main), and it actually hurt the high rpms where it seems like it has a rev-limiter or something.

I haven't changed the spark plug, but it looks okay, and the gas in the tank is about 3-4 months old, but it was always in a good location (basement...consistant temperature). I drained the gas before, and it didn't help then either.

Thanks to any help!
Kevin

P.S. the carbs seem to be as clean as a whistle! I've cleaned them a couple times, and the fuel seems to go wherever it should (I don't reallly know how much should flow through, however...I suppose some might be restricted, even though they seem fine.)

[CRXSi90]

Okay, I was wrong about the part of killing the top end part, it'll still rev up just fine, without and with load.

The bottom end is still deader than a door nail.

I tried turning the petcock to "off" and riding it...it seems like there is no level that will satisfy it, low rpms were horrible the whole time.

If I slowly turn the throttle open, while in neutral, it will stay at idle or just above idle, and then just take off through the roof! There is no in-between with this thing! Weird.

It doesn't seem like the choke helps the problem much.

What are the chances that this problem is electrical related?

[Geezer]

I haven't worked on any 2 strokers in a while but I'll give you a few things to check.

When any bike isn't running right, do a compression check. It never hurts to know... Next clean the exhaust baffel. I've always doen this outside with a propane torch. Also you may need to clean the carb, there's a good chance the pilot jet is plugged.

Geezer

[CRXSi90]

Hey, thanks for replying! I was worried I wouldn't get a bit of help!

The compression test isn't a bad idea, too bad I don't have the tool! I found a few online from JC Whitney and Checker. I could also visit Bumper to Bumper, but they don't have a site. Any recommendations in what to look for in a tester?
$29.99
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$82.99

Exhaust baffel? Would that be something inside the muffler? The muffler doesn't separate from the exhaust pipe, so would cleaning it from the back side be sufficient?

I took the pilot jet out yesterday, and it appeared clean, as did the main jet. I sprayed some wd-40 through the pressed in jet, and it came out where the screw in jet goes, and out a little hole in the venturi area (I think).

How much would a jet that is the wrong size affect the performance? If there is a K&L or whatever carb. rebuild kit for this, and they frequently use the wrong jets, it would figure that it was done.

This is a bike with a magneto, not pickup coils like XS's. What problems do those give.

Also, being a 2-stroke, it has reeds for the intake, I guess. Is there a good way to check them?

Thanks for overwhealming yourself by my side!

[CRXSi90]

I figured out how to clean the muffler...there are a few bolts and clamps, and the inside of the muffler slides out. I shot the propane torch through it a bit until it didn't smoke so horribly, and it had what seems like decent flow.

While it was cooling, I took the bike for a ride without the muffler in, and it still exhibited the same problems.

I don't get it, when I took the carb apart this spring, there seemed to be something in the pilot jet...cleared that, and its still like this!

What are the chances that bad gasoline would cause this problem? I would think there would be a greater negative effect in the high-rpm range, but what do I know...

Just fyi, its oil injected, so no premixing of the gas...

[CRXSi90]

Small update...

The choke seems to help it run a little better, not perfect though. It doesn't die as bad with the choke on, but sometimes it does anyway.

Sometimes it dies with the choke off and won't start until I turn the choke on.
Sometimes it dies with the choke on and won't start until I turn the choke off.

Weird.

[Geezer]

Ask around to see if any of your friends have a compression tester but it's sure sounding like carb problem. You may have to get some one more experienced to check out the carb.

Geezer

[CRXSi90]

ugh, okay, thanks. I'll probably be back when I make some progress. One thing I haven't done is blown out the carb passages. I suppose that would be worth a shot. Hopefully I can bring it to school wed. and use their stuff to do that. I'll ask around while I'm there, too.

Thanks again,
Kevin

[cruiser]

try this

Kevin,
Once you are sure ALL the passages in the carb are clean and it's adjusted properly and compression is good, check these items.
I've had a number of kaw 2 strokes and these are common problems I've run in to.

1. Check to make sure the throttle valve isn't binding at all when you open the throttle. This can cause the "idle to wide open" syndrome you talked about. To do this pull off the rubber from airbox to carb and without it running twist the throttle slowly and watch the valve from the rear of the carb.

2. Check for vacumm leak at the carb to head, rubber boot and the reed valve gasket by idleing and spraying carb cleaner or starting fluid around that area to check for RPM change.

3. Check exhaust ports at the head for carbon buildup by removing the head or exhaust pipe to see the ports.

Hope this helps.
Cruiser

[CRXSi90]

That will keep me busy for a while. Thanks! A couple questions before I begin, though.

Properly Adjusted:
There appears to be no "air screw" on this carburetor. In the service manual, it has a picture pointing to the "air screw" and nothing is there! (LOL) I've heard of there being a plate that covers the screw from the factory, but this looks like it was never drilled in. Don't worry, I'll get a picture of what the book shows, and what is actually there.

Also, the idle thumb-screw has some issues too. The slide is kinda gouged where it contacts the idle screw. It seems like I can crank it in all the way, and there is no change in idle to speak of. Sometimes, however, with the idle screw in pretty far, it will just decide to REV IT UP! I wonder if it only catches some of the time, or something, and thats when the "full throttle syndrome" kicks in. If I recall correctly, someone said that on XS11 CV or whatever carbs with the vacuum slide, you could rev it up, and the slide would immediately fall even iif you held the revs.

To check the level in the float bowl, I have to have a special plug to put in the bottom of the float bowl that has a hole in it. Do you have any suggestion about how to make one, or should I just go buy the real thing? It seems like if you got the right size bolt, and drilled through the middle, possibly a little larger on the end inside the carburetor to make room for the main jet.

Thanks for the help!

[CRXSi90]

If the needle is even adjustable, what would happen if I raised it?

[cruiser]

carb tips

After looking at parts fiche it appears there is no air adjusting screw. See link for parts breakdown.
http://www.buykawasaki.com/site/VIVe...&SHOWVEHTABS=1


The throttle valve is all mechanical. As it slides down it hits and sits on top the idle adjusting screw which is tapered. Turning the screw in should raise the throttle valve for faster idle. The throttle valve must move up and down freely. Perhaps being gouged is causeing it to "hang up" intermittantly.

For float level I went to hardware store and purchased a plastic plug with a nipple on it about the same size as the drain plug at bottom of bowl along with short piece of clear vinyl hose to attach to the nipple and route up the side of the carb. Then turn on fuel to fill bowl and measure level in hose to side of carb.
The plastic plug is not the same thread but was able to thread into bowl and make new threads on plastic plug.
Adjusting sucks as you have to drain and take apart to adjust float and assemble and try again.

Some jet needles on these carbs which go inside the throttle valve have 4 or 5 adjustment rings which you can change to adjust mixture on main jet. By reading the numbers on the main jet it will tell which ring on the jet needle the circlip should go.

Are you totally confused now

[cruiser]

Air Screw

If you have an air screw that is covered it should be on the right side of carb covered by soft plug. This screw adjusts the air mixture to the pilot jet only for 0 to 1/8 throttle.
I don't believe you have one though and all the more reason to make sure ALL ports inside carb are clean.
I recommend using carb cleaner with plastic nozzle instead of WD-40 and spray in pilot jet again along with any other openings.
Also spray through any small ports in the venturi area, there should be a couple of tiny openings.

[CRXSi90]

I think I overlooked a partially plugged pilot jet the past 2 or 3 times I cleaned the carb. This time, I think I got it! I dunno what was in there, but it looked like fiberous material, so that some gas could pass, and so could most of the light.

At least I know a little more about the bike now than before!

Out to go for a test ride, wish me luck!

[CRXSi90]

Oh do I feel stupid! After cleaning it a few times, I finally got it. I had wondered how any gas can actually get through that little hole...I guess it is because it isn't all open. Before, I used a toothpick which wouldn't fit in the jet down to the hole. This time, I used a fine piece of copper wire, and ran it around the outside of the hole a few times.

Guess what, it runs like a dream!

Thanks for the help, sorry you had to educate me about stuff I didn't need to be educated about to fix the problem. At least I'm a little more educated now, though!

Kevin