Mikuni RS34 carbs

Beautiful bike there baldy110. Must be like an awesome dream to be able to work on and ride those fine machines.

Please elaborate on the carburetor accelerator pump system, and the effects it has on jetting?

Thanks guys.
I have the AP come in right around 1/4 throttle any sooner and the gas is shot onto the slide which does no good.
The pump only comes on when you twist the throttle as long as you are aware of this it doesn't effect the jetting. I tune each circuit individually starting with the idle circuit then mid hrottle then full throttle. And since these circuits don't require the throttle to be moving to tune then the AP doesnt effect the tuning process. I've read to disable the AP but I've never had an issue leaving it in play while tuning. I guess if you've never tuned a rack of carbs and don't understand how each circuit works I could see how the AP could mask a lean condition.

Ok I got a weird issue that came up with these carbs. I decided to run overflow tubes this time. On the other RS carbs I've run in the past I never used them just left the overflow on the bowl as it was. Well I've been noticing a small puddle of gas under the overflow tubes everytime I parked the bike after a ride. It wasn't from the float system as I would leave the manual petcock on trying to see if it would overflow it never did.
It turned out to be the overflow tubes themselves. I removed them and now no gas comes from the overflows. Best I can guess would be the way I routed the hoses and as the bike was ridden there would be some Bernoulli effect that would suck small amount of gas from the float bowls. Then when I would park the bike the gas in the tubes would just drain out. Without the tubes the bowl overflows stay dry.

I have this issue on both bikes with flatslides. I figured it was a float bowl issue as it will do it all night unless i turn the petcock off. I checked the float heights and polished the float needle jets to try and rectify the problem. Eventually i just gave up and chalked it up to a quirk of the carbs. just a couple of drops of fuel no big deal, turn the petcock off. I will remove the overflow tubes and see if that changes anything

Same issue with mine. Would drip mostly from #1 and maybe a little less from #2, which I attribute to leaning off-level on the kickstand. When removing the #4 bowl cap I have found that most of the fuel had already been drained from that carb, and progressively less from the next on down after standing undisturbed for some hours.

I wonder if the fuel seeks level via the accelerator pump system.

DoctoRot wrote: I have this issue on both bikes with flatslides. I figured it was a float bowl issue as it will do it all night unless i turn the petcock off. I checked the float heights and polished the float needle jets to try and rectify the problem. Eventually i just gave up and chalked it up to a quirk of the carbs. just a couple of drops of fuel no big deal, turn the petcock off. I will remove the overflow tubes and see if that changes anything

I can leave the manual petcock on all night and won't leak a drop but ride it then park it on it's centerstand and I get drops from the tubes. It is a weird issue but since the overflows don't leak I'll just leave the tubes off.

SWest wrote: OK ya got me. MORE PICS :woohoo:
Steve

Reference to post: kzrider.com/forum/3-carburetor/611781-mi...arbs?start=12#815241

Took another dive into the remote idle adjustment giZmo, and rectified the issue.





It works!


:woohoo:





.

Very tidy Looks OEM, good job.

baldy110 wrote: Very tidy Looks OEM, good job.

Rest assured...he'll be back.

New member. I have RS 40's and trying to get them tuned in. I have a 93' ZR 1100 its a 1360cc 12.5:1

Need help.  Are the settings for RS34 cabs I'm setting it up on my kz1000 p.. the bike is bone stock 

kz1000jay wrote:

Need help.  Are the settings for RS34 cabs I'm setting it up on my kz1000 p.. the bike is bone stock 

Maybe someone running them on a 1000 will chime in.

When you say bone stock you should also specify what you have for exhaust and filtration.

In the Mikuni Manual there is no jet listing for RS34's on a 1000 with because they start with a 750 (race carbs) there are jetting recommendations for the 1000 but for RS36/38's




I have a set of RS34's but they are on my 650 which runs a 831cc engine. It runs good with #20 pilots and #122.5 mains. These carbs would not run well on such a small engine but I have extensive cylinder head mods which makes it flow more than a GPZ1100.