Mikuni BS34 Air & Fuel Circuit Diagram

Can anyone please provide me a detailed diagram showing ALL the air and fuel circuits/paths for my BS34 carbs (1982 KZ1000P1)?

I want to clean them and make sure all passages are open; for example, there are three tiny holes by the butterfly which I'll try to stick some fishing line through, but it would be nice to know where it's suppose to come out.

I downloaded www.mikuni.com/pdf/vmmanual.pdf but don't know if it's my carb. And I have two service manuals but they seem to show generic/major paths only.

Thanks!

i used to have a side view of where all the little circuits go but i cant find it anywhere sorry.

May I suggest going ahead & doing the complete teardown so that the carb bodies can be soaked. Doing so should take care of any problem orifices that might be plugged.

Doing so isn't that bad. A lot of the same thing is done four times & most stuff only goes back together one way. I did a set of VM carbs for the first time several years ago, and it really seemed quite easy to me. Instead of bothering w going back-n-forth referencing the manual, I just used my eyeballs & common sense to get them apart. A clean work area is helpful & 4 small parts containers are goood for keeping things organized.

JMKZHI wrote:

May I suggest going ahead & doing the complete teardown so that the carb bodies can be soaked. Doing so should take care of any problem orifices that might be plugged.

Doing so isn't that bad. A lot of the same thing is done four times & most stuff only goes back together one way. I did a set of VM carbs for the first time several years ago, and it really seemed quite easy to me. Instead of bothering w going back-n-forth referencing the manual, I just used my eyeballs & common sense to get them apart. A clean work area is helpful & 4 small parts containers are good for keeping things organized.

The reason I'm taking the carbs off again (just had them off) is that I didn't put back the pilot jet plugs; but the bike started great and ran great...until the combination of over 1/2 throttle over 4,000 rpm; then it would start coughing and slow down; if I backed off the throttle it would be fine up to red-line. So I'm going to put the jet plugs back (when they arrive on Thursday), but I figured I would do are more thorough cleaning job; however, in that the bike ran pretty good aside from what I think is the plug issue, I'm not looking to max out on the tear down; mistake?

Without the pilot plugs it Will run rich....

Put the cabs back on; no more revs breaking up problem. So looks like without the pilot jet plugs this bike won't run right. But now that I put them back, it runs great and the spark plugs are light coco brown now.

I removed the plugs from my 34's back in July. The bike seems to run great. Another rider rode it yesterday and told me it was a lot smoother than his shaftie.

I'm getting 44.6 MPG. I've been checking it every time i fill up. About three times a week.

If jeff has some in stock i am going to order some pilot jet plugs tomorrow. :huh: Roy

I had to go to ronayers.com for my pilot plugs, but I think Z1 said they could have ordered them for me if I called. But why would you want to put them back in? Sounds like your bike runs great without them.

I have two more sets of 34's and i want to expeirment with the jetting.

Jeff only has the suzuki plugs and you have to trim them down as they are rubber. Roy

It does seem that my bike started better when cold without the plugs. My idle screws are still the stock 1 1/4 turns out; I wonder if adjusting them would effect cold starting. When the bike's warmed up, the idle is solid; I run it kind of low (around 950 RPM) as that lessens the clunk going into 1st from neutral.

There is a default setting that I'm not certain of. You can start at 1 1/2 turns out to begin tuning.

If the float heights are set properly and everything is clean, the # of turns should be very close.

With the bike good and hot, and carbs synced properly. Turn ALL THE PILOT SCREWS either in or out 1/2 turn and listen to the idle. The idle should noticably rise or fall. continue turning if the idle rises, turn the other way if it falls.

The idea is to find the spot at which the idle is highest.

Then, turn each one individually 1/4 turn either in or out and listen. Try to find the spot at which the idle is highest again. They should be very close, and if no audible change is detected at this point, your done!

Good luck!

This will assist cold starting some with the BS34s.