1983 KZ550F1 problems need advice thanks

Dear KZ fanatics ,

I have purchased a 1983 KZ550F1 (20K miles) in very good shape recently.

There's a few problems that i want to fix in order to have a smooth ride.

However finding specific informations for this model is scarce and i have the genuine shop manual from Kawasaki.

1. Poor acceleration/performance in the low-mid rpm range (less than 5000 rpm)

While riding until about 5000 rpm the acceleration is slow hard to explain how slow (feels like a 150cc motorcycle)
then when reach 5500-6000 rpm then suddenly the accel. its strong enough to make me slip on the seat the rpm needle raise very fast!

Maybe the causes are: bad carb synchronization, lean mixture and ... clogged pilot jet BUT the guy told me he rebuild and clean all the carbs including jets.

I've ordered Carbtune Pro and Colortune spark plug waiting for them to arrive.

2. Little oil leaking from the valve cover.

Maybe the valve cover gasket need to be changed.

3. Noise while the engine is cold (valve and chain noise)
then go away when the engine is hot...

Maybe valve clearance and with thermal expansion, clearance go away? i don't know seriously.

Btw, is there something else i need check/adjust for the poor performance at low rpm or a carb synchro and correct mixture will fix this problem.

Thank you very much for you time!

Best Regards,
Laurent

Sounds like a jetting issue poor fuel supply. Also check Ing. advancer may need lubed sticking.Just my thoughts..

definitly sounds like a carb problem to me what does it have for a pipe does it still have the stock airbox also just because the cat say's he cleaned the carb's don't mean shit if he didn't know what he was doing. or actually did it i have seen some peoples idea of cleaned carb's before spraying a can of carb cleaner on the body of the carb is not cleaning them. as far as the noises go try sdetting the cam chain tensioner to factory settings it shouldclean up a lot of your noises.

ELCouz wrote:

Dear KZ fanatics ,

I have purchased a 1983 KZ550F1 (20K miles) in very good shape recently.

There's a few problems that i want to fix in order to have a smooth ride.

However finding specific informations for this model is scarce and i have the genuine shop manual from Kawasaki.

1. Poor acceleration/performance in the low-mid rpm range (less than 5000 rpm)

While riding until about 5000 rpm the acceleration is slow hard to explain how slow (feels like a 150cc motorcycle)
then when reach 5500-6000 rpm then suddenly the accel. its strong enough to make me slip on the seat the rpm needle raise very fast!

Maybe the causes are: bad carb synchronization, lean mixture and ... clogged pilot jet BUT the guy told me he rebuild and clean all the carbs including jets.

I've ordered Carbtune Pro and Colortune spark plug waiting for them to arrive.

Do you have a manual?
Use this link for carb tuning:
www.factorypro.com/tech/carbtun.html

When someone else says they went through the carbs, and they didn't let you know what jetting is in there, and you're not the original owner of the bike, who really knows what's in there?

2. Little oil leaking from the valve cover.

Maybe the valve cover gasket need to be changed.

If it's leaking from the sides of the valve cover, then it's more than likely the cam end plug seals, and when the valve cover is removed for a valve clearance inspection, high temp black adhesive, like "Right Stuff" should be used to help them seal better.

3. Noise while the engine is cold (valve and chain noise)
then go away when the engine is hot...

Maybe valve clearance and with thermal expansion, clearance go away? i don't know seriously.

Sounds like almost normal cam chain noise. The tensioner on these bikes, seem to be more noisy when at idle either cold or warm. I'd let this one go, or replace the tensioner with an APE Manual Cam Chain tensioner, or upgrade to a Zephyr ZR550 Factory Tensioner, that has steps in it, instead of the ramps the stock unit has.

Btw, is there something else i need check/adjust for the poor performance at low rpm or a carb synchro and correct mixture will fix this problem.

Thank you very much for you time!

Best Regards,
Laurent

Start with checking valve clearances, and a tight valve can give running issues. You gotta know. 0.10mm - 0.20mm(.004" - .008") intake and 0.15mm - 0.25mm(.006" - .010") exhaust.

Good luck.

Sounds like a jetting issue poor fuel supply. Also check Ing. advancer may need lubed sticking.Just my thoughts..

I will take a look to the timing advancer today thanks!

definitly sounds like a carb problem to me what does it have for a pipe does it still have the stock airbox also just because the cat say's he cleaned the carb's don't mean shit if he didn't know what he was doing. or actually did it i have seen some peoples idea of cleaned carb's before spraying a can of carb cleaner on the body of the carb is not cleaning them. as far as the noises go try sdetting the cam chain tensioner to factory settings it shouldclean up a lot of your noises.

The guy which i bought the motorcycle is a coworker i trust him. (i told me today that he passed a wire inside the jets) but thanks i will disassemble all the carbs when the riding season is finished.

Do you have a manual?

Yes, the original old 1982 repair (service) manual from Kawa. I found there's a lot of informations missing such as wire routing, cable routing took me a while to catch where to pass the damn cable clutch !!!

If it's leaking from the sides of the valve cover, then it's more than likely the cam end plug seals, and when the valve cover is removed for a valve clearance inspection, high temp black adhesive, like "Right Stuff" should be used to help them seal better.

Wow! right guess its exactly leaking from the black half-round part thank you i will fix that in the winter.
thanks!

Sounds like almost normal cam chain noise. The tensioner on these bikes, seem to be more noisy when at idle either cold or warm. I'd let this one go, or replace the tensioner with an APE Manual Cam Chain tensioner, or upgrade to a Zephyr ZR550 Factory Tensioner, that has steps in it, instead of the ramps the stock unit has.

I will let my worries go on this one, the guy told me its normal, it always been like that he told me (noisier when cold , quieter when warm).

Start with checking valve clearances, and a tight valve can give running issues. You gotta know. 0.10mm - 0.20mm(.004" - .008") intake and 0.15mm - 0.25mm(.006" - .010") exhaust.

I will check this when fixing the oil leaking, but there's one thing I'm afraid shims for this motorcycle aren't available anymore I've looked for kz550 shims on ebay only 2 size showed up.

Oh btw, is the engine from the kz550 shared with any others kawa motorcycles ?


thank you guys for your advices

Best Regards,
Laurent

As timebomb33 asked: " ...what does it have for a pipe does it still have the stock airbox..."

Has this bike the curse of the pods?

As timebomb33 asked: " ...what does it have for a pipe does it still have the stock airbox..."

Has this bike the curse of the pods?

The air filter has been changed this year.

Btw, I've lubricated the timing advancer no improvements yet.

I remember the guy talking that he also played with the mixture adjustment screw, screw in then unscrew 2 and half turn but this method is not precise. Without proper analyzing tools its very hard to know if you're running lean, ok or rich.Counting the turns of the screw is not a good way of doing this (from my pov). Gas analyser is friggin' expensive so i will give a try to the colortune spark plug.

/me waiting impatiently for the carbtune and colortune kit to arrive

Regards,
Laurent

I will check this when fixing the oil leaking, but there's one thing I'm afraid shims for this motorcycle aren't available anymore I've looked for kz550 shims on ebay only 2 size showed up.

Oh btw, is the engine from the kz550 shared with any others kawa motorcycles ?

Shims are still available from Kawasaki. Z1 Enterprises that advertizes here, sells them as well.
www.z1enterprises.com/
Your's uses the 13mm diameter shims, but until you check the clearances, and measure the shim you have in there, you won't know wich one to order.

I remember the guy talking that he also played with the mixture adjustment screw, screw in then unscrew 2 and half turn but this method is not precise. Without proper analyzing tools its very hard to know if you're running lean, ok or rich.Counting the turns of the screw is not a good way of doing this (from my pov). Gas analyser is friggin' expensive so i will give a try to the colortune spark plug.

Seat the mixture screws, carefully, and turn them out about according to your manual. Not sure what carburetors you are running. Are they vaccum slide carbs, or mechanical carbs?

First things first, assume the guy didn't clean the carbs, I'd recommend you go through them yourself, and make sure everything is set, and write down the jetting numbers. Check with your manual to see if the jetting in there is stock. This is the only way you'll know. You should be able to reuse the float bowl gasket, as long as they don't tear when removing the bowls.

Shims are still available from Kawasaki. Z1 Enterprises that advertizes here, sells them as well.
www.z1enterprises.com/
Your's uses the 13mm diameter shims, but until you check the clearances, and measure the shim you have in there, you won't know wich one to order.

Yes i know i will check the clearance this winter when i will take off the valve cover.

Seat the mixture screws, carefully, and turn them out about according to your manual. Not sure what carburetors you are running. Are they vaccum slide carbs, or mechanical carbs?

Vacuum carbs, by the way i've received the colortune and the setting in the manual is not correct still way too lean... misfiring a lot and the flame is whitish blue.
Now I've make it more richer orangish blue (2 turns more) wow acceleration is very smooth no tendency to stall at the throttle being opened quickly.

First things first, assume the guy didn't clean the carbs, I'd recommend you go through them yourself, and make sure everything is set, and write down the jetting numbers. Check with your manual to see if the jetting in there is stock. This is the only way you'll know. You should be able to reuse the float bowl gasket, as long as they don't tear when removing the bowls.

Thanks for the infos i will disassemble them after the seasons finished.

Btw, all the carbs are perfectly synchronized at idle and this engine has never been checked for this before.
How this can be possible in the manual they says i need to check/adjust first 800km next 5000 km after that every 10000 km (6200 miles).

What can cause the carbs to be desynchronized ?

Also, when i will open the valve cover , i expect a lot of carbon deposit inside. Is it better to leave it there or clean everything with acetone ?

Thank you fellow KZ riders !

Best Regards,
Laurent

How do you know they are synch'd without connecting a gauge?

In my experience, they don't go out of synch, but carbs may need cleaning or "degumming" eventually, and everytime you open carbs, is better to check the synch. It is not a big deal if you had a gauge.

There should not be any carbon buildup under the valve cover. It should all be clean oil. You are not separating the valve head.

hi hugo,

How do you know they are synch'd without connecting a gauge?

I've finally received Carbtune Pro and Colortune spark plug that's why

There should not be any carbon buildup under the valve cover. It should all be clean oil. You are not separating the valve head.

Alright, but then if i see some carbon deposit this means the valve don't seal properly, leaking exhaust in the valve cover right ?

After nearly 33500 km (21k miles) i don't expect to see the top clean i don't know if this engine is prone to make «sludge» (without prestone of course )

thank you for your support!,

Regards,
Laurent

Before you vacuum sync the carbs, you'll need to know if your valve clearances are within spec. Even if you have a good color with that color tune you have, doesn't mean the carbs are in sync. Motion Pro makes a new tool, and I just bought one. Excellent is an understatement. Do one bike, and you'll want to do others, even if they aren't your own.

I believe you should have TK26 Carbs on that bike, right? Idle adjustment knob is between #2 and #3, no? These carbs have a cap covering one of the ports near the main jet, once the bowls have been removed. It's critical that you do not lose these. They are no longer available from Kawasaki, and the carbs will not run right without them being there. You should also make notes of what jets are in there, and compare that to what www.Kawasaki.com shows you have. No telling what the previus owner did.

So, you have the stock airbox and stock exhaust in place with just a new air filter?

You can tell about the servicing of the engine by what color the inside of the valve cover is, once you remove it to inspect valve clearances. Remember, it's and '83 and only 21,000 miles on it, so how many oil and filter changes do you think it's had in those miles? More sitting than riding I'd guess. I'd recommend only 20w-50 motorcycle specific engine oil, and non-synthetic, no matter what the outside temp is. These engines run hot, and even with an external oil cooler, I've run mine ine the 240-270 degrees F range, getting the temps from the oil pan on a 95 degree F day. 20w-50.

With the age of your engine, and the lack of oil changes, you main comcern is #3 Rod bearing spinning, that's the weakest link. I've seen this on one of my bikes I had been riding for 6,000 miles, after aquiring it at 38,000 miles, and even after changing the oil and filter 3 times within that mileage. Good clean oil and fliter is the key.

I agree, you shouldn't see any carbon under the valve cover, that would be in the combustion chamber.

Drop the oil pan, and you can see what's in there. There would be your sludge from lack of service. Look for any silver flakes, and that would be bearing surface material(Aluminum).

OK that should do for now.