33mm Mikunis

[torkezilla]

Hi all
First post here
I'm doing some maintenance on a friend's bandit400. It's supposed to be
a full power model whatever that means, not really familiared with all the
bandit models. It has single brake disc in front.
Well anyway, I was cleaning and rebuilding the carb rack, they're
mikunis CV 33mm, I know some other models had 32mm's.
One thing I noticed is that the pilot jets (inside the carb bowls) were
plugged with a small rubber plug.
My question is why? Does this come from the factory? From where do the
carbs feed at lows revs?
What will happen if I remove this plugs?
carb specs are:
mains: 102.5
needles: stock on #3
pilot jets: 32.5
mix screws: 2.5 turns from fully in.

Any input appreciated.
Cheers all

Ricardo

[Thief400]

On these CV carbs Mikuni wants all the fuel to be meter thought the main jet then off to the pilot jet, If you remove the plug you will bypass the main jet and the bike will run too rich. Some guys have done this and reported that the bike ran better but they had some major jetting issues.
Leave the plugs in place. The 33'd came with 100 mains so someone has rejetting already. You might want to richen the needle one notch if you have the dreaded 4 to 6000 rmp flat spot. Other than that just drive her and enjoy

[Bandit]

I'm riding a 93 GSF400P my  carb spec similar to yours,  except my needle has only 1 groove for the e-clip, the mixture screw setting is still stock because the factory seal is still intact.  I have tried to remove the rubber covering the pilot jets and it runs smoothly in the low rev compare to before, stock setting for the pilot circuit is too lean I think.

During the yearly inspection, CO check is 0.8 for my bandit400 with rubber seal over pilot jet compare to my 93'gsxr750 at 1.2 without.

[torkezilla]

That was my guess since the fuel must come from somewhere to feed the pilot circuit. I thought the pilot circuit must have some sort of communication witht the main jet circuit.
So the 102.5 jets are already bigger than stock, This is good since I'm trying to see if I can improve the filter and airbox flow.
I already got the needles up a notch to fatten up the midrange, generally stock jettings are always way to lean from the factory, but thanks for the tip.
For the guys with non-adjustable needles, you can shim them up a bit with a little washer under the plastic piece. Some electronics shops have these tiny washers.
Thanks all for the feedback, I'll keep visiting the forum, for anything I might of help, don't hesitate to ask.

Ricardo
torkezilla@netvisao.pt