Monza 250 NC manifold options

[Blaine.Hale]

I'm looking to mount up any carb that isn't the stock UBF 24 BS Dellorto on my Monza. I currently have a Dellorto VHB 26 F that's roughly jetted for a 250 that I'd like to try out. Problem is, I need a manifold solution. The OD on the VHB cylinder side spigot is 36mm and it's the rubber mount variety. The studs on the cylinder are the stock 52mm center to center spacing.
Can y'all think of anything out there that would help get this thing mounted up, or will it be a custom situation?

Side note: I have an email with Sudco to inquire about a MIkuni as well. Do they offer manifold solutions to go with the carbs?

[Duccout]

I have a 28mm Mikuni on my 250, and a manifold is available, although you would have to remove the manifold studs and turn down the heads of the metric cap-head screws to allow them to fit inside the manifold's recessed holes (this is in the UK, Sudco possibly has specific manifolds). The plus point is that the Mikuni is rubber mounted.

[Blaine.Hale]

I have a 28mm Mikuni on my 250, and a manifold is available, although you would have to remove the manifold studs and turn down the heads of the metric cap-head screws to allow them to fit inside the manifold's recessed holes (this is in the UK, Sudco possibly has specific manifolds). The plus point is that the Mikuni is rubber mounted.

Turns out Sudco has a VM26 "baseline" jetted with the proper manifold to bolt it up. Amazing how these places have such niche information to jet these carbs. I'm betting $100 they only know this because awesome folks from this and other forums have provided them with that data.
So I guess that's the end of this thread! I would have preferred a Dellorto for the looks and being Italian but a bolt on solution sounds awesome to me.

[gregwils]

It seems like everyone here loves the Mikuni. I bought the baseline VM26 from Sudco, but my Monza was not happy with it and I never got it set up correctly. It was very hard to start and seemed to run toward the rich side. I also didn't love the look of a modern Jap carb on my old Italian, but that's me.

In frustration, I purchased an Amal (Aluminium Premier RH 24mm 4 Stroke Carburettor - 624/300AL). After further reading, I decided to match the carb throat and head diameter, so went with 24mm. I have to say the bike ran perfectly from the first kick. In fact, it sat for three weeks just recently, and at summer air temperatures, it started on the first kick and had no problem idling cold until I road it away. Is there untapped power because I am running a 24 vs a larger carb? Maybe, but it runs so great I don't care. Plus, it looks far more period correct to me, similar even to the old Dellorto.

Just thought I would share another option. Good luck with your decision.

PS - If anyone is interested in a slightly used (a few years old and about 100 miles) Mikuni VM26 from Sudco, feel free to PM me.

[Jordan]

I also like Amal Concentric carbs, and have mentioned here that I never had a Ducati single run better than with one fitted - a 30mm on a Mark 3 widecase.
Original Concentrics wear their slides out after a few years, but currently made versions have better materials so should last much longer.

[halfpast]

I put an Amal 626 on my Monza, bolted right up to the intake perfectly. The bike ran great.

[blethermaskite]

I have always used mk1 concentric carbs on all my Ducati's over many years, and currently have these fitted to my 350mk3 and 250 desmo no issues at all, both run perfectly, if I acquired any other ohc Ducati I would automatically fit the amal concentric........I have tried just about every carb, amal gp. ssi dellorto, vhb delorto, gardener flat slide, wal philips fuel injector, keihin flat slide, and others I have forgotten the amal mk1 was the best.....but you must put a proper amal velocity stack on these to get the best performance.
Cheers,
George

Ps. Fresh and clean fuel always works the best

[Blaine.Hale]

Do any of you fellas have the jet numbers for your amals? I'm entertaining the idea of trying out a 626, like y'all mentioned. I can always kick my Mikuni over to my Mark 3 Desmo for another day.
I assume people used:
MAIN JET 150

NEEDLE JET 106

THROTTLE SLIDE 3.0

[Blaine.Hale]

I put an Amal 626 on my Monza, bolted right up to the intake perfectly. The bike ran great.

Did you settle on the jets posted in here? How did you sort your initial issues out? viewtopic.php?f=3&t=2289

[blethermaskite]

All my bikes are using 930's or 932's so my jetting is not much use to you, however if it were me starting from scratch....base settings would be ....fixed non adjustable pilot jet, 3/1/2 slide, std needle,106 needle jet, 160 ish? main jet.......bear in mind you should be starting with setting the main jet first, then working down through the lower settings.
Cheers,
George