carb tune help/procedure

650ed wrote:

blink543 wrote:

650ed wrote:
? :blink: ? If you have a manual go back and re-read through the section on synchronizing the carbs. You do NOT fiddle with the air screws to synchronize the carbs. The air screws have nothing whatsoever to do with carb synchronization. Ed

They do. In the manual it says it's supposed to mess with the air to fuel mix. Then what does it do

What manual are you using?? If it say to sync the carbs you are "supposed to mess with the air to fuel mix" throw the manual away and buy Kawasaki Service Manual. You do NOT fiddle with the air/fuel mixture to synchronize the carbs. You DO adjust the individual throttle adjusting screws to synchronize the carbs. However, if you have gotten the air screws out of adjustment by fiddling with them you will first need to undo whatever it is you did to them. Ed

They are mikuni air screw type carbs. It's a clymer manual why would it lie? I'm not throwing it out.

blink543 wrote: I've been wondering why when I accelerate its kinda laggy and kinda sounds boggy when I open it all the way up.I was told it's probably the carbs. I've tuned them before but I probably did more bad than good. The gauges I used were in inches hg not cm hg like noted in the manual. I went online and converted the cm needed to inches and it said a little over 8 inches hg. So I did that but it's hard to keep it from revving and dealing with the idle screw too. What's the procedure in trying to balance them? Do I go in order carb 1-4?

boggy when I open it all the way up -- bogging at wot is likely not related to carb sync and not related to pilot air screw adjustments.

If not already done, would perform clear tube test.

Good Fortune!

blink543 wrote:
They are mikuni air screw type carbs. It's a clymer manual why would it lie? I'm not throwing it out.

Clymer manuals are known to have mistakes, but it's difficult for me to believe it says to adjust the air screws to sync the carbs since that is totally wrong. Can you do us a favor and post a picture of the text? No offense intended, but I suspect you are mis-reading something. Ed

Clymer,etc. are a one size fits all. The one I have covers multi years. There were a lot of changes from 73-80 mainly carbs. The first section is "Mechanical Synchronization. It tells about using the solid wire (drill bit) to bench sync the carbs. It then tells about the "clear tube test" then idle adjustment screw. What bothers me is it jumps to taking all the carbs apart. NOT ROUTINE. Normally just a clean up of the float bowls is needed. Too easy to get into trouble following this thing. I know what I'm looking at but a noob wouldn't.
Steve

Are you adjusting the screw under the carb top that has 3 screws (holding it down)and loosening the locking nut before turning it ? If so your doing it right......... my Clymer calls them throttle adjusting screws............ and consider getting a factory manual "too" I always read up from both before doing anything I have a question about.

swest wrote: Clymer,etc. are a one size fits all. The one I have covers multi years. There were a lot of changes from 73-80 mainly carbs. The first section is "Mechanical Synchronization. It tells about using the solid wire (drill bit) to bench sync the carbs. It then tells about the "clear tube test" then idle adjustment screw. What bothers me is it jumps to taking all the carbs apart. NOT ROUTINE. Normally just a clean up of the float bowls is needed. Too easy to get into trouble following this thing. I know what I'm looking at but a noob wouldn't.
Steve

Yes that is kinda what I'm talking about. I wanna sync them back to factory since I was fine tuning them with the vacuum gauges. Obviously I probably should have taken the carbs out and mechanically synced them first but I really didn't wanna do that the boots were a pain to get back in. I'm ordering new boots so they will be easier to get back in since they will be new because I wanna get these carbs back into the best possible tune.

This all reminds me of a line from Cool Hand Luke...What we have here is a failure to communicate. You may be using the wrong names and doing it right, or using the right names and doing it wrong.
The air/fuel screw is a straight slot screw on the side of the carb. You do adjust it from the top using a long screw driver. It is also the first step in running adjustments of your carbs. However, it is not used for carb synchronization. That comes later. Each air/fuel screw is adjusted individually. Turn each one clockwise until it stops. Count the number of turns and write that down as a fallback reference. Now turn them out counter-clock wise 2-2.5 turns (check the manual for your bike). Start the bike and adjust the air/fuel screw of each carb individually for maximum rpms. Turn 1/4 turn and listen. If the rpms increase, do another 1/4 turn in the same direction. If they decrease, go back the opposite direction. Work down to 1/8 turns. Do this for all 4 carbs.
With the air/fuel screws properly adjusted, you are ready to sync the carbs. This is a mechanical adjustment of the slide position so each carb has equal draw and the cylinders share the load evenly. Connect your gauges and compare readings. You are not after a predetermined number. You just want all 4 to be close to the same number. Adjustment is under the top cover of the carb. Loosen the locking nut and turn the slotted adjuster. Some bikes have 1 non-adjustable carb (master) that you adjust the other 3 to. I believe the 650 does not, so it's your pick. If you have 2 carbs close, adjust the others.
The Clymer manual is not as good as the factory, but it does have some value. If it's all you've got, it's better than nothing. Just pay close attention to the terms. Cam shaft and Crank shaft sound similar, be we all know there's a big difference. Same thing with carb screws. They may sound similar, but have completely different functions.

MDZ1rider wrote: This all reminds me of a line from Cool Hand Luke...What we have here is a failure to communicate. You may be using the wrong names and doing it right, or using the right names and doing it wrong.
The air/fuel screw is a straight slot screw on the side of the carb. You do adjust it from the top using a long screw driver. It is also the first step in running adjustments of your carbs. However, it is not used for carb synchronization. That comes later. Each air/fuel screw is adjusted individually. Turn each one clockwise until it stops. Count the number of turns and write that down as a fallback reference. Now turn them out counter-clock wise 2-2.5 turns (check the manual for your bike). Start the bike and adjust the air/fuel screw of each carb individually for maximum rpms. Turn 1/4 turn and listen. If the rpms increase, do another 1/4 turn in the same direction. If they decrease, go back the opposite direction. Work down to 1/8 turns. Do this for all 4 carbs.
With the air/fuel screws properly adjusted, you are ready to sync the carbs. This is a mechanical adjustment of the slide position so each carb has equal draw and the cylinders share the load evenly. Connect your gauges and compare readings. You are not after a predetermined number. You just want all 4 to be close to the same number. Adjustment is under the top cover of the carb. Loosen the locking nut and turn the slotted adjuster. Some bikes have 1 non-adjustable carb (master) that you adjust the other 3 to. I believe the 650 does not, so it's your pick. If you have 2 carbs close, adjust the others.
The Clymer manual is not as good as the factory, but it does have some value. If it's all you've got, it's better than nothing. Just pay close attention to the terms. Cam shaft and Crank shaft sound similar, be we all know there's a big difference. Same thing with carb screws. They may sound similar, but have completely different functions.

Well on these carbs I don't see any adjustment screws on the sides. I'm not sure. The manual says nothing about that. Just the top air screws on the carbs

MDZ1rider wrote: This all reminds me of a line from Cool Hand Luke...What we have here is a failure to communicate. You may be using the wrong names and doing it right, or using the right names and doing it wrong.
The air/fuel screw is a straight slot screw on the side of the carb. You do adjust it from the top using a long screw driver. It is also the first step in running adjustments of your carbs. However, it is not used for carb synchronization. That comes later. Each air/fuel screw is adjusted individually. Turn each one clockwise until it stops. Count the number of turns and write that down as a fallback reference. Now turn them out counter-clock wise 2-2.5 turns (check the manual for your bike). Start the bike and adjust the air/fuel screw of each carb individually for maximum rpms. Turn 1/4 turn and listen. If the rpms increase, do another 1/4 turn in the same direction. If they decrease, go back the opposite direction. Work down to 1/8 turns. Do this for all 4 carbs.
With the air/fuel screws properly adjusted, you are ready to sync the carbs. This is a mechanical adjustment of the slide position so each carb has equal draw and the cylinders share the load evenly. Connect your gauges and compare readings. You are not after a predetermined number. You just want all 4 to be close to the same number. Adjustment is under the top cover of the carb. Loosen the locking nut and turn the slotted adjuster. Some bikes have 1 non-adjustable carb (master) that you adjust the other 3 to. I believe the 650 does not, so it's your pick. If you have 2 carbs close, adjust the others.
The Clymer manual is not as good as the factory, but it does have some value. If it's all you've got, it's better than nothing. Just pay close attention to the terms. Cam shaft and Crank shaft sound similar, be we all know there's a big difference. Same thing with carb screws. They may sound similar, but have completely different functions.

Ok so looking closer underneath the carbs there's an adjustable screw there's no screws on the sides just the bottoms and inside of the tops. Not sure what model these are from but on my frame it says kz650b

About your carbs. You stated "They are mikuni air screw type carbs." Do your carbs look like the ones pictured below, and are the air screws indicated by the arrows the screws you have been adjusting trying to synchronize your carbs? If those are the screws you are fiddling with you have been wasting your time becausue those are NOT what you adjust to synchronize your carbs. If those are not the screws you have been adjusting PLEASE post a photo of your carbs and the screws you have been adjusting. Ed

Pics, need pics. Who know what the PO put on there.
Steve

650ed wrote: About your carbs. You stated "They are mikuni air screw type carbs." Do your carbs look like the ones pictured below, and are the air screws indicated by the arrows the screws you have been adjusting trying to synchronize your carbs? If those are the screws you are fiddling with you have been wasting your time becausue those are NOT what you adjust to synchronize your carbs. If those are not the screws you have been adjusting PLEASE post a photo of your carbs and the screws you have been adjusting. Ed

The screws I've been adjusting are on the inside on the top there's three screws to take off the top and there's a screw with a locking nut I've tried putting up pics before and it doesn't work