my day

[ducatiman]

these Mikuni's now precisely returned back to stock configuration using both (stock supplied) 140 mains and 5C22 needles with other tricks as well. I'll proclaim these will run near perfect. Ready to go home to owner.

[Triple Jim]

What size are they? They look quite different from my VM34s.

[Bob KellyIII]

lol yah that might by why the jets are too big...the carbs are off something else and are too big for the engine ! ....didn't think of that ! thanks Jim !
....
Bob.....

[ducatiman]

nice try, but these BDST38 Mikuni are the originally suppied CV carbs on 900,750 and 600cc (both SS and Monster models) up till '98 or '99 when they went to FI. Both jetting and internal differences existed between various models.

[ducatiman]

on yet another set of 250 carbs today, some pics to follow.

[ducatiman]

majority of the day spent on these.....

[ducatiman]

just arrived....a set of 250's allegedly leaking from RH carb side. I'll do a wet test first....prior to proceeding. Being used on a kart application.

[ducatiman]

supposedly "rebuilt"....I'll take exception to that. Immediate wet test cancelled/cleaning to take precedence.

Note EPA caps never removed to enable both cleaning of the involved pilot port(s) and oring replacement

These carbs were never split, on all 4 vent and fuel delivery rails the orings were both extremely hardened and dirty.

Nice float valve seats, too. I'm not surprised carbs were internally "leaking".

Hang in there for pics after my cleaning is done!

[ducatiman]

gut shot.....a lil' bit better, perhaps?

[ducatiman]

nearing completion, currently wet testing, both carbs perfectly stable, ZERO leakage, internally or externally. Wrapping it up tomorrow.

I'll surmise the leakage was due to dirty float seats, coupled with possibly incorrect float valves, more on that later after a comparison and precise measurement. More tomorrow. I'm played out today.

[ducatiman]

On left the original float needle (from a Far East carb kit used previously) and my currently installed needle on right

Note the Far East version leaked from RH carb
Mine are holding reliably in both carbs

May/may not be related in view of the poor condition of the seats as found.

Anyways, differences are obvious.

[ducatiman]

and a couple of photos of completed carbs, ready to return to owner

[ducatiman]

currently rebuilding a trade-in set of EX500 carbs, to be #114 and intended to be sold. A pic or 2 will be posted here when done in 24-48 hours.

[ducatiman]

#114 completed this mornin'

[ducatiman]

a set of Ducati/Mikuni CV carbs here for refurb.....all the usual, totally clogged pilot jets and 1 main jet. All ports/jets/bodies required and received my attention. See pics. Tomorrow will reattach the set, wet test and prep for return shipping.

[Omnitech]

I legit just scrolled through all 10 pages of this. You do stunning work! I just rebuild my carbs and if they don't work I know who I'm going to. I come from tuning VW's with a laptop so this is all uncharted for me haha.

[ducatiman]

Thanks for your comment, Eric but hopefully you've got it all under control.

[maverick9611]

the fj carbs will be comin soon sir.
your work is always top notch

[ducatiman]

TY Mav

as always....ready, willing and able but no rush, send in your time

[maverick9611]

taking it up to the mountains next week with my mountainrunners group will be at two wheels suches georgia. well see what it can do
heres rick from mountainrunners on a fjr

[maverick9611]

Originally Posted by ducatiman

TY Mav

as always....ready, willing and able but no rush, send in your time

are you familiar with the 36 mm mikuni?

A lot of the guys are upgrading from the 37 to 40 pilot jets what is your take on it?

[ducatiman]

upsizing pilot jets very likely requires re-adjustment of pilot screws.Depending on how the bike initially runs....may or may not be worth it.
Is yours running ok or not?

[maverick9611]

Originally Posted by ducatiman

upsizing pilot jets very likely requires re-adjustment of pilot screws.Depending on how the bike initially runs....may or may not be worth it.
Is yours running ok or not?

running fine. no issues

[ducatiman]

in that case, why mess with it?

[maverick9611]

Originally Posted by ducatiman

in that case, why mess with it?

your right

[ducatiman]

finished the Ducati/Mikuni's posted about earlier. Pic attached.

[ducatiman]

a 50 mile ride on my normal North Shore route, upon returning home changed oil and filter on my Honda. So 1 down....2 to go and I'll be up to date with maintenance procedures on my own motorbikes!