My Suzuki GS550 has a smaller version of the same model of Mikuni carburettor, VM22SS. It took me a while to get the fuelling balanced on all of them. With the same jetting, needle positions, air screw settings and fuel screw settings, I was still getting variation in plug colour between cylinders. I'd already stripped and cleaned them several times, so was confident all the passages were clear. I decided to leave the air screws at Suzuki's standard setting of 2 turns out and make adjustments just on the fuel screws. Initially, I used a Colortune kit to get a base setting, then fine-tuned them the old-school way, by road testing and checking plugs until I got all 4 the right colour. Runs beautifully now.
Right on Rick! Patience and perseverance are key when dialing in carburetion/tuning (and many other aspects of vintage restoration). It is awesome that your patience paid off!
Spark plug appearance is a good tool to indicate carburetor performance. A laser heat gage at headers for uniformities as well. Valve lash settings are correct and uniform compression amongst the cylinders. No obstructions in fuel delivery pathway. All carb jets and ports clean. A fuel filter is always a good idea. Float levels and fuel flow float tip and seat in good condition. Clean and oiled air filter if applicable. Ignition mapping correct regardless of system used . On air cooled all finning clean and no obstruction for air flow. Liquid cooling clean and proper glycol distilled water mix and radiator and all related passages clear. Kawasaki world renowned for dependable motorcycle engines. Iridium plugs are superior and well worth cost. A comfortable yet stylish seat well worth the efforts. Beautiful vintage Kawasaki.😊
Thanks, Bill! All great points. I am going to a stock carb setup with the stock airbox. The race carbs and pod filters are not really designed for the type of street riding that I'm looking to do. Cheers!
@@jonsmotorcyclerescueandrev3538 For sure friend and happy motoring. My new “ yellow ball “ is fuel injected and liquid cooled both firsts for my bike lineup. First bike 1976 KT 250 78 KD 100 79 KX 250 80 KX 250 80 GPZ 550 82 KX 250 82 KE 175 82 KLT 250 82 KZ 750 91 GSX 1100 G ( 160 mph capable) 92 Intruder 1400 ( gorgeous custom cruiser) 92 DR 350 ( 32,000 trail miles ) 14 KLX 140 24 Z900 rs se I do all my own maintenance and tire changes. 45 + years riding experience.
@@billbright1755 Very cool! You've had some nice machines over the years. I would love to review the Z900 RS at some point. They're beautiful machines!
Very cool! I have wanted one most of my adult life and it's sureal to finally have one in the garage. I was working on it again today. Hopefully I'll get some nice weather for a test ride tomorrow.
Someone else mentioned it below I believe, but your mixture screws should not necessarily be all turned out exactly the same. They should be tuned per carb. Each carb will be slightly different from each other. Even from the factory they were never set exactly the same. Also, have you checked your valves clearances on this bike? I don't remember if you have, but that could be causing problems. Also, if those are the original intake boots, they need to go. 40 year old rubber boots do not seal well. This has gotten me several times in the past, thinking they looked good, when in fact they weren't. I would definitely change those. Otherwise, the bike is coming along great and it sounds great too.
Thanks Rob! I was testing and tuning again yesterday. Boots are new with sealant used at the engine. Valve clearances were checked. The weather has turned cold here so that complicates tuning. It runs 90% now even in 45 degree weather so it is getting closer. I may need to go up on my needle jets since I haven't been able to completely dial out a lean spot at around 45-50 mph. I'll keep tuning and keep everyone posted on the progress.
Thanks for posting Jon. I`m working on the exact same project. I believe your bike has later model discs on it. Years ago I put my brothers Z1`s tank and flat seat on my 1979 KZ 1000 ltd, I believe I had to make a large loop with the fuel line because the petcock locations where differant. I would like to know what jets you ended up using. My project bike has K&N pods, non-pump VM26 carbs & a Mac 4>1 pipe. ND is at about 18000 feet above sea level. I believe for my first rip I`m going to run 119 Mains, 115. pilots, Zed air correctors & factory needles, and needle jets. I would be very greatful for your opinion. Again, Thankyou!
Hi Steven, I recently found out that my carbs are VM29 smooth-bores. Also, I'm much lower altitude wise. I'll let you know my final setup once I get it completely dialed in. Cheers!
It’s not a blocked fuel line issue because when he loads the motor with more throttle & rpm it takes np into higher rpm. Jon, if the carbs had 2 somewhat blocked idle passages it would not idle well at all and would run bad under at approx 1/4 throttle & lower throttle positions which it doesn’t sound like it’s doing. I was listening closely to throttle position in the video & what I heard was when you thought a cyl or 2 was cutting in & out here are 2 easy things to check & remedy it. But before going what rec below if your still running original 40-45yr old rubber intakes you think look & seal good 9 of 10x you would be wrong! Been there don’t that too many times in working on these bikes for 4+ decades finding no matter how good the 40-45 yr old rubber looks you can still have head to intake seal issues even with fuelproof sealer. And that’s not to mention the 40-45yr old rubber can have microscopic cracks you can see with backed eye or low power magnifying glass either causing vacuum signal/leak issues. So if you haven’t replaced the 40-55 yr old rubber intakes yet do so before going any further with carb tuning because it can send you chasing your tail by overichening the lower carb circuit on those 2 lean cyls. Next is you never stated if you checked to ensure needle clips were in proper 3rd slot from top on the carbs needles so chk & adj as needed. Too often people have needle clip in the 4th from top slot position which is too rich even when running a fairly tame 4into 1 with stock motor setup like we talked about prior on this bike along with the pilot & main jets I suggested you try too. Ok,now we can proceed. Fully warm up the motor by riding it for 10-15 mins & then return home. Now with motor hot at idle check /adjust the idle mixture screws 1st in till idle rpm drops then back out till you get highest smooth idle on each cyl. If you found 1-2 cyls that idle speed increased when you richened the idle screws go for a test ride to see if the problem is gone,if yes your good to go as long as all plugs look med to light tan & not still black or dark brown showing too rich. Note,the 1976 26mm carbs have pilot screws closer to air filter intake therefore controlling are at idle di in being less are is richer & out letting more are in is leaner. But if the 26mm carbs you have have idle mix screws under carbs thru float bowls (1977 26mm carbs) controlling the fuel Turing them in is leaner & out is richer. And don’t get too hung up on each pilot screw being approx same amount turns in or out. Important thing is that your able to obtain a steady smooth idle post adj. Now another thing that can seemingly cause a flight misfire or lazy cyl or at steady state low throttle position cruise that gos away as soon as you give it a hair more throttle is is if you don’t have carbs absolutely perfectly sync’d using a proper vacuum tube/gauge setup. You can get carb sync close to run pretty good just like yours is doing but it doesn’t always get it close enough like vacuum gauge setup does that eliminates an issue with 1-2 slides actuation a hair behind the other slides which can cause the exact issue your having sending you chasing your tail. Lastly,if you look at the pic I sent you of my 78 Ltd I installed the. Bit larger A model tank like you mentioned,looks a bit nicer scalp wise & gets you done addition fuel capacity/miles in between fillips too. Good luck! Scott a fellow 78 KZ1000 LTD & H1 Triple owner!
Hi Scott, I just found out that my carbs are VM29 smooth-bores. So, jetting, needle clip settings etc. are completely different than on stock carbs. Carb boots are new and installed with sealant. I am still dialing the carbs in and will share what my final settings are when I get there. Thanks for the insight. It gives me a good starting point when I get into my next KZ1000 project (a 1977 LTD with stock carbs).
Ah,29mm carbs likely off a Z1 900. But it the bike sounds like you have the bike/motor running pretty good at this point with only fine fine tuning left to do & like you said that’s the little PIA detail stuff that often takes the most effort & time to get corrected. Btw,even though you have 29mm’s on the bike everything I mentioned in my prior post here about the rubber intakes,carb sync being in little off & or idle mix being a bit off can all cause the little misfire /lean looking plugs issue you talked about all still hold true as things to chk out. Good luck! Scott
I recently rebuilt the carbs on a Kawi 750 air cooled engine (2001 zr7S). The carbs for the inner cylinders (2,3) were jetted richer (presumably because they run hotter) so it’s possible your jets got mixed? The needle jets on 2,3 had more holes than on 1,4. I had rebuilt the carbs on a 1000 engine but did them one at a time without mixing the parts so I didn’t notice if there was a difference on the inner carbs.
1# and 2# fuel line is same. Maybe there is some flowing problem, vacuum fuel tap wont deliver enough gasoline for that line ? Put clear thin pipe lifted from bowl lower hole alongside of carburettor frame will tell real fuel line. Do this when engine is running and get some revs for engine and look how fuel line react.
@rickdevarenne4479 Hi Rick, it's a 1978 KZ1000 LTD. I'm converting it to the KZ1000 A style by changing the font fender, tank, seat, and paintwork. It will still be an LTD, but it will look like the A. Cheers!
@@jonsmotorcyclerescueandrev3538 , thank you, do you have any videos of you setting the carbs? It’s been over 30 years since I have set valve lash and carbs tuned carbs.
@@russ3080 I will try to do a video on carb synching and valve checking in the future. I started a valve check video on the 1981 CSR1000 but had a power outage as I was finishing it up. I will check to see if it is usable as-is.
Aah the memories.... In the 80s and 90s I had a 1980 LTD 1000 and then a 1978 LTD 1000....
Sure wish I had them back now.
The prices are getting higher now. I'm glad that it finally makes sense financially to restore them. For many years, they weren't a good investment.
My Suzuki GS550 has a smaller version of the same model of Mikuni carburettor, VM22SS. It took me a while to get the fuelling balanced on all of them. With the same jetting, needle positions, air screw settings and fuel screw settings, I was still getting variation in plug colour between cylinders. I'd already stripped and cleaned them several times, so was confident all the passages were clear. I decided to leave the air screws at Suzuki's standard setting of 2 turns out and make adjustments just on the fuel screws. Initially, I used a Colortune kit to get a base setting, then fine-tuned them the old-school way, by road testing and checking plugs until I got all 4 the right colour. Runs beautifully now.
Right on Rick! Patience and perseverance are key when dialing in carburetion/tuning (and many other aspects of vintage restoration). It is awesome that your patience paid off!
Amongst my many bikes through the years 1980 GPZ 550, 1982 KZ 750 four, 2024 Z900 rs se.
Kawasaki lets the good times roll 🏁
Right on!
Spark plug appearance is a good tool to indicate carburetor performance.
A laser heat gage at headers for uniformities as well.
Valve lash settings are correct and uniform compression amongst the cylinders.
No obstructions in fuel delivery pathway. All carb jets and ports clean. A fuel filter is always a good idea. Float levels and fuel flow float tip and seat in good condition.
Clean and oiled air filter if applicable.
Ignition mapping correct regardless of system used . On air cooled all finning clean and no obstruction for air flow. Liquid cooling clean and proper glycol distilled water mix and radiator and all related passages clear.
Kawasaki world renowned for dependable motorcycle engines.
Iridium plugs are superior and well worth cost.
A comfortable yet stylish seat well worth the efforts.
Beautiful vintage Kawasaki.😊
Thanks, Bill! All great points. I am going to a stock carb setup with the stock airbox. The race carbs and pod filters are not really designed for the type of street riding that I'm looking to do. Cheers!
@@jonsmotorcyclerescueandrev3538 For sure friend and happy motoring.
My new “ yellow ball “ is fuel injected and liquid cooled both firsts for my bike lineup.
First bike 1976 KT 250
78 KD 100
79 KX 250
80 KX 250
80 GPZ 550
82 KX 250
82 KE 175
82 KLT 250
82 KZ 750
91 GSX 1100 G ( 160 mph capable)
92 Intruder 1400 ( gorgeous custom cruiser)
92 DR 350 ( 32,000 trail miles )
14 KLX 140
24 Z900 rs se
I do all my own maintenance and tire changes.
45 + years riding experience.
@@billbright1755 Very cool! You've had some nice machines over the years. I would love to review the Z900 RS at some point. They're beautiful machines!
I had pretty much the same bike, 1980 kz1000 with 4-1 vance hines pipes, wish I still had it.
Very cool! I have wanted one most of my adult life and it's sureal to finally have one in the garage. I was working on it again today. Hopefully I'll get some nice weather for a test ride tomorrow.
Someone else mentioned it below I believe, but your mixture screws should not necessarily be all turned out exactly the same. They should be tuned per carb. Each carb will be slightly different from each other. Even from the factory they were never set exactly the same. Also, have you checked your valves clearances on this bike? I don't remember if you have, but that could be causing problems. Also, if those are the original intake boots, they need to go. 40 year old rubber boots do not seal well. This has gotten me several times in the past, thinking they looked good, when in fact they weren't. I would definitely change those. Otherwise, the bike is coming along great and it sounds great too.
Thanks Rob! I was testing and tuning again yesterday. Boots are new with sealant used at the engine. Valve clearances were checked. The weather has turned cold here so that complicates tuning. It runs 90% now even in 45 degree weather so it is getting closer. I may need to go up on my needle jets since I haven't been able to completely dial out a lean spot at around 45-50 mph. I'll keep tuning and keep everyone posted on the progress.
I had the same issue with a 80's Kawasaki GT550, nearly drove me crazy.
Right on!
Thanks for posting Jon. I`m working on the exact same project. I believe your bike has later model discs on it. Years ago I put my brothers Z1`s tank and flat seat on my 1979 KZ 1000 ltd, I believe I had to make a large loop with the fuel line because the petcock locations where differant. I would like to know what jets you ended up using. My project bike has K&N pods, non-pump VM26 carbs & a Mac 4>1 pipe. ND is at about 18000 feet above sea level. I believe for my first rip I`m going to run 119 Mains, 115. pilots, Zed air correctors & factory needles, and needle jets. I would be very greatful for your opinion. Again, Thankyou!
Hi Steven, I recently found out that my carbs are VM29 smooth-bores. Also, I'm much lower altitude wise. I'll let you know my final setup once I get it completely dialed in. Cheers!
that is a small tank that green one is some nice
gd vid job. good old kaw.
Thanks David!
It’s not a blocked fuel line issue because when he loads the motor with more throttle & rpm it takes np into higher rpm.
Jon, if the carbs had 2 somewhat blocked idle passages it would not idle well at all and would run bad under at approx 1/4 throttle & lower throttle positions which it doesn’t sound like it’s doing.
I was listening closely to throttle position in the video & what I heard was when you thought a cyl or 2 was cutting in & out here are 2 easy things to check & remedy it.
But before going what rec below if your still running original 40-45yr old rubber intakes you think look & seal good 9 of 10x you would be wrong!
Been there don’t that too many times in working on these bikes for 4+ decades finding no matter how good the 40-45 yr old rubber looks you can still have head to intake seal issues even with fuelproof sealer.
And that’s not to mention the 40-45yr old rubber can have microscopic cracks you can see with backed eye or low power magnifying glass either causing vacuum signal/leak issues.
So if you haven’t replaced the 40-55 yr old rubber intakes yet do so before going any further with carb tuning because it can send you chasing your tail by overichening the lower carb circuit on those 2 lean cyls.
Next is you never stated if you checked to ensure needle clips were in proper 3rd slot from top on the carbs needles so chk & adj as needed.
Too often people have needle clip in the 4th from top slot position which is too rich even when running a fairly tame 4into 1 with stock motor setup like we talked about prior on this bike along with the pilot & main jets I suggested you try too.
Ok,now we can proceed.
Fully warm up the motor by riding it for 10-15 mins & then return home.
Now with motor hot at idle check /adjust the idle mixture screws 1st in till idle rpm drops then back out till you get highest smooth idle on each cyl.
If you found 1-2 cyls that idle speed increased when you richened the idle screws go for a test ride to see if the problem is gone,if yes your good to go as long as all plugs look med to light tan & not still black or dark brown showing too rich.
Note,the 1976 26mm carbs have pilot screws closer to air filter intake therefore controlling are at idle di in being less are is richer & out letting more are in is leaner.
But if the 26mm carbs you have have idle mix screws under carbs thru float bowls (1977 26mm carbs) controlling the fuel Turing them in is leaner & out is richer.
And don’t get too hung up on each pilot screw being approx same amount turns in or out.
Important thing is that your able to obtain a steady smooth idle post adj.
Now another thing that can seemingly cause a flight misfire or lazy cyl or at steady state low throttle position cruise that gos away as soon as you give it a hair more throttle is is if you don’t have carbs absolutely perfectly sync’d using a proper vacuum tube/gauge setup.
You can get carb sync close to run pretty good just like yours is doing but it doesn’t always get it close enough like vacuum gauge setup does that eliminates an issue with 1-2 slides actuation a hair behind the other slides which can cause the exact issue your having sending you chasing your tail.
Lastly,if you look at the pic I sent you of my 78 Ltd I installed the. Bit larger A model tank like you mentioned,looks a bit nicer scalp wise & gets you done addition fuel capacity/miles in between fillips too.
Good luck!
Scott a fellow 78 KZ1000 LTD & H1 Triple owner!
Hi Scott, I just found out that my carbs are VM29 smooth-bores. So, jetting, needle clip settings etc. are completely different than on stock carbs. Carb boots are new and installed with sealant. I am still dialing the carbs in and will share what my final settings are when I get there. Thanks for the insight. It gives me a good starting point when I get into my next KZ1000 project (a 1977 LTD with stock carbs).
Ah,29mm carbs likely off a Z1 900.
But it the bike sounds like you have the bike/motor running pretty good at this point with only fine fine tuning left to do & like you said that’s the little PIA detail stuff that often takes the most effort & time to get corrected.
Btw,even though you have 29mm’s on the bike everything I mentioned in my prior post here about the rubber intakes,carb sync being in little off
& or idle mix being a bit off can all cause the little misfire /lean looking plugs issue you talked about all still hold true as things to chk out.
Good luck!
Scott
@@scottwheaton9689 Right on! I appreciate the insight you bring.
I recently rebuilt the carbs on a Kawi 750 air cooled engine (2001 zr7S). The carbs for the inner cylinders (2,3) were jetted richer (presumably because they run hotter) so it’s possible your jets got mixed? The needle jets on 2,3 had more holes than on 1,4. I had rebuilt the carbs on a 1000 engine but did them one at a time without mixing the parts so I didn’t notice if there was a difference on the inner carbs.
Really nice KZ. 👍
No difference in parts. I will cover what I am doing to get things squared away in the next video.
@@blipco5 Thanks!
Nice update Jon, good luck with the last few details on this one it's looking great! How did you test your carb boots?
Thanks Doc! They're new boots with new vacuum plugs. I used sealant as well.
1# and 2# fuel line is same. Maybe there is some flowing problem, vacuum fuel tap wont deliver enough gasoline for that line ? Put clear thin pipe lifted from bowl lower hole alongside of carburettor frame will tell real fuel line. Do this when engine is running and get some revs for engine and look how fuel line react.
Thanks Jim. That's a great suggestion. I've continued to make progress and will continue to post updates.
That Bike is a 900 LTD John, have one Doessthave small tank
@rickdevarenne4479 Hi Rick, it's a 1978 KZ1000 LTD. I'm converting it to the KZ1000 A style by changing the font fender, tank, seat, and paintwork. It will still be an LTD, but it will look like the A. Cheers!
Great video! What tool do you use to sync the carbs?
Vacuum dial guages. I have used this set on many bikes with good success.
@@jonsmotorcyclerescueandrev3538 , thank you, do you have any videos of you setting the carbs? It’s been over 30 years since I have set valve lash and carbs tuned carbs.
@@russ3080 I will try to do a video on carb synching and valve checking in the future. I started a valve check video on the 1981 CSR1000 but had a power outage as I was finishing it up. I will check to see if it is usable as-is.
@@jonsmotorcyclerescueandrev3538 thank you, that would help me a bunch! Really appreciate it!👍
Didn't even work on the carbs!! Shifty video
Sorry about that. I wasn't trying to be shifty 😏