79 KZ650 engine smoking

So, i got my first bike, this KZ mid winter for a pretty good deal. ill upload a picture later though. its got 13,700kms on it. i was out riding with a few buddies last night and at first i noticed a bit of a drop in power, but thought little of it as i had a passanger with me. about an hour later i was coming up a pretty sizeable hill and noticed the smell of somehting burning, but it diddnt smell like oil. when i got to the top of the hill at a set of lights, i put my hand over the exhaust and revved it up. smelled my hand and it smelled like.. cluch almost, more than oil.

it had been rebuild last summer, thats why i bought it. so unless they did a shabby job of it, it shouldnt be in ill repair this early in the season. being as its my first im not all that in the know about what to look for other than fouled plugs . i was hoping the forum would have some suggestions? id apprecieate them lots. its gorgeous today and i have no bike to ride lol.

upon further inspection of the smoke its quite light in color, and smells more of gas than oil. perhaps its a simple adjustment? thanks for the help again all.

Would first check crankcase oil level, AND examine physical condition of the oil, AND sniff-test it for any evidence of fuel contamination.

Good Luck!

my oil level is a bit high, but it doesent shift as well when its right between the lines in the sight glass. the gas should be fine, the guys i was riding with all had it in their tanks. the oil is dark but seems to be in good condition aswell.

Id start by checking condition of plugs you can tell a lot about the engine by the plugs look for a medium brown color if there glossy wet looking it probubly is fuel see if there is any sign of oil if they if that does not narrow it for you run a compression test and check your air box for signs of oil possibly coming from vent its not very common but can happen and an extremly clogged air filter will cause a loss of power and a rich condition we really need more info to help narrow it down more i hope this helps

CTait wrote:

my oil level is a bit high, but it doesent shift as well when its right between the lines in the sight glass. the gas should be fine, the guys i was riding with all had it in their tanks. the oil is dark but seems to be in good condition aswell.

Not a matter of gas quality in the fuel tank.

It's to negate the possibility that any gas has invaded the crankcase due to faulty float valves or other carb defect.

If crankcase oil passes the sniff test, would next verify that service floatbowl fuel level is correct, as being too high may alone cause excessively rich mixture in an otherwise perfect carb.

Good Luck!

Any unusual engine noise?

Combustion in all four cylinders?


Good Luck!

you said loss in power do you mean that it feels as if the bike isn't moving as fast as the engine is reving or do you mean that the engine itself has a boggy running problem??????? that may help narrow it down

Patton wrote:

CTait wrote:

my oil level is a bit high, but it doesent shift as well when its right between the lines in the sight glass. the gas should be fine, the guys i was riding with all had it in their tanks. the oil is dark but seems to be in good condition aswell.

Not a matter of gas quality in the fuel tank.

It's to negate the possibility that any gas has invaded the crankcase due to faulty float valves or other carb defect.

If crankcase oil passes the sniff test, would next verify that service floatbowl fuel level is correct, as being too high may alone cause excessively rich mixture in an otherwise perfect carb.
the crank case oil smells fine, whats the float bowl? is it the clear-ish pod that has fuel pass from the tank to the carbs? it doesent seem overly full. heres a shot of my plug, i wouldnt think it to be THAT bad. but all the plugs are just like this one. the engine sounds fine, nothing unusual other than the loss of power in and around 5 grand. all cylenders are firing fine. the bike still runs great, its just the smoke coming from the exhaust i need to figure out. www3.telus.net/public/codym4/IMG_1378%5b1%5d.JPG

the air filter is fine aswell Buckinrut.

chevyhead, it just feels like its missing power in the higher rpms. like its starving for fuel would be my guess, because its obviously not being burnt haha
Good Luck!

have you checked the plug gap by chance??????? if not you should that plug looks to be pretty bad at least from the pic. i would check the gap my 78 kz 650 was doing just this minus the blackness on the plug but the same symtom and it was all cause my plugs were worn to an accesive amount to 40 thousands and the max for mine was only 32 thousands it ran ok but from about 6200 rpms to red it would'nt do it it ran great other wise.

CTait wrote:

... whats the float bowl? is it the clear-ish pod that has fuel pass from the tank to the carbs? it doesent seem overly full. heres a shot of my plug, i wouldnt think it to be THAT bad. but all the plugs are just like this one. the engine sounds fine, nothing unusual other than the loss of power in and around 5 grand. all cylenders are firing fine. the bike still runs great, its just the smoke coming from the exhaust i need to figure out...the air filter is fine... just feels like its missing power in the higher rpms. like its starving for fuel would be my guess, because its obviously not being burnt....

Sooty plugs may be result from:

Inadequate compression (often corrected with valve clearance adjustment);

Poor spark quality (several underlying possibilities);

Too high fuel level inside floatbowl;

Too rich internal jetting inside carbs (this doesn't magically change from good to bad absent some rare failure such as maybe a mainjet coming loose).

The clearish pod inside the fuel line between the petcock and carb is the always highly recommended accessory inline fuel filter that gas passes through on its way to the carb float bowls. It almost never looks totally full.

Would start by removing all sparkplugs and visually observe spark quality on brand new plugs while spinning the engine over in neutral with ignition ON, and holding base of both plugs from same coil against the engine head. Look for fat blue spark.

While plugs are out, perform compression test, remembering to hold throttle wide open during the test.

A good shop manual is an essential tool, and the official Kawasaki Service Manual (FSM) for the particular model is usually the best shop manual. Available on ebay. And there are some downloadable manuals here on KZR and from other websites. They cover the above procedures and infinitely more.

Good Luck!

What plugs are you using? If they're the wrong heat range they will soot/foul. Ed