Mikuni BS34 info

shade_tree wrote:

going to price boots now.

May I suggest...

www.z1enterprises.com/detail.aspx?ID=411

Yay!

I have a running motorcycle for under $500...Wow! And a shiny clean one at that.

Those boots you linked me to Skyman are worth the money if they are soft and flexible, these original ones on this bike are pretty hard...there is nothing else wrong with them, no cracks, just hard. Since i cannot get the carbs onto them they are worthless.

Help pleaze? so the the bike fires up nice on a few turns of the crank with the choke at the halfway clik. It idles on the half way choke setting as well. when i push the choke in, the bike stalls. I let it run for three minutes or so on half choke and still stalls upon turning off the choke.

I don't know where to set those Pilot screws because i could not turn them in past the crud when i took them apart. Idunno if that has to do with this choke thing or not.

Also, i have not attached any vacuum guages for synch-ing the crabs...need to rig that set up yet. I left the factory glued settings be underdisturbed durring the rebuild and the glue is still on those adjustors.

I turned the idle idjustment this way and that to no avail.

I am test running with straight carbs, no filtration, no conection to airbox.

Ohh "Guru of Gas", i come seeking wisdom and guidance once again.

Yay...i have a motorcycle! Wish i could ride it.

I am test running with straight carbs, no filtration, no conection to airbox.

The engine will not run properly without everything in place correctly, and no air leaks.

Hookup the air box and filtration man, and I bet it'll run much better :lol:

Cheers!

...and yes, new boots will be soft and pliable.

shade_tree wrote:

I don't know where to set those Pilot screws because i could not turn them in past the crud when i took them apart.

According to the manual that I gave you the link to, on page 3-2 (at the bottom of the page), it says to set the screws at 1 1/4 turns. This is the default starting position. After you get it running, you can adjust them for highest RPM.

Thanx Tech9ine...need to have it all hooked up before adjusting anything is valid.

what about "pilot screws"....how many turns on those pesky pilot screws?

I looked all over that manual! All i could find is tthe same thing you said...turn them in and record the the finding.

1 1/4 turns...got it. Dude...you truely are the "the Pope of Pistons", "the Raji of Kawasaki"..."the Rabbi of Riding"

turning scews now.

How I adjust them is usually...

I start the mixture screws at 2 turns out.
Point a descent fan at the headers...
Then, with a nice hot engine, set the idle down lower than normal (I find it makes it easier to hear changes in the idle).

1 at a time, SLOWLY turn the screw inward and listen for the increase in rpm. Find the highest rpm for each carb, using very small adjustments.

I like to check them over twice just to be assured.

Theres lots of other methods... like starting at the said stock default. I've found that default is never accurate. Probly because of altitude/air density/etc...

Good Luck! :silly:

ALSO... the Wiredgeorge Coil Mod works fantastic, and you should seriously consider doing it! www.wgcarbs.com/index.php?option=com_con...view&id=12&Itemid=26
I've had it solve many different problems!

Gentleman...i thank you for all of this great advice.

Pilot screws adjutments make a differnce...at the recommended 1 1/4 turns the thing now idles without choke.

I have reached my goal...to see if this old bike will run...and it does. sounds good too. putting the rest of parts back on now.

I'll likely start a new thread with whatever arrises next unless there is more carb issues.

I checked that coil reading like the wiredgeorge set up explains and came up with 11.7 v. ...not bad out of twelve available.

you guys rock.

no problem on the hijacking...

Your post gave me the balls to dig into my carbs.So here is my new problem carbs are rebuilt and very clean I might add pilot screws are set at about 1 and 1/2 turns out.The bike will start and hold idle till you give it some throttle after that it seems to want to accelerate on it's own.What would be the cause of this?

hey grinch...I got my carbs put together and on the bike after i bought some new intake boots. The pilot screws seem tomake a difference even with the slightest of adjustments, I started at 1 1/2 turns and the bike ran good but with poor performance at low RPM, then to 1 1/4 turns where the bike ran much better, very fast and scary, but was hard to start when hot, I settled at 1 3/8 turns...a bit hard to start when hot but runs real good at all RPM. Scary fast.

I have only had this motorcycle for a month or so and only riden it 200 miles so far. It's been over thirty years since i owned a bike, so this is all experimental for me. I dont know what is correct, but on my KZ 1000 on a cold start, choke on...the thing will begin to idle nicely then slowly rev up to about 4200 RPM...i push the choke in to the mid position and it slows down to normal idle, then revs to 4200 RPM at that position upon warming...once its all warmed up and choke off, the thing idles nicely at 1000 RPM.

I wonder if your issue has to do with the choke, i am having similar symptoms as you, but with choke on. the only other thing i can think of is the throttle cable not seated in the little goodie that holds it, or the throttle adjustment on the bars is too tight...perhaps there is a throttle adjustment at the carb linkage...idunno, idid not remove my carbs from the rails when i took them apart...perhaps also that since you took the carbs apart maybe they are not synchronized. I got lucky i think and the old factory settings seem to be working well enuff to go 0 to 80 in about 4 seconds. Fun stuff!

reving engines are often caused by vacuum leaks on cars...probobly true with motorcycles too...check the hoses.

ohh...and don't forget about that idle adjustment screw...it comes in handy for adjusting the idle! I forgot about mine and wondered what the hell had gone wrong...then it dawned on me an hour after i gave up...turn up the idle! Hopefully its as simple as adjusting the throttle cable to have just a microportion of free play at the grip and then turning the idle adjuster while tickling the pilot screws. And the air cleaner needs to be in too or the thing won't run right either.

peace and good luck.
~K~

What is the base setting for the main idle adjustment screw or a good starting point on it?