Better carb in kit

I am getting closer to having a ridable 750 Comando. Have been thinking about it and would consider changing to Mikunis or better yet also going to a single. Would enen consider a single Amal.

How ever I do not want to go chasing after things like cables/adaptors to make it work. So a complete kit would be best for me. Anything out there?

Wolfman said:

I am getting closer to having a ridable 750 Comando. Have been thinking about it and would consider changing to Mikunis or better yet also going to a single. Would enen consider a single Amal.

How ever I do not want to go chasing after things like cables/adaptors to make it work. So a complete kit would be best for me. Anything out there?

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There are several sources. Matt at cNw does a twin flat slide kit that’s plug n play. He also does a single Mukuni kit for those who don’t mind losing some power above 5,000 rpm.

Depends largely on how you ride the bike,
If you want a boring bland ride then go for a single VM 34 or 36 mikuni.
If you want performance go for twin carbs or a single tm40 , Cheers

check with https://www.rockypointcycle.com, he is on this board

Wolfman said:

I am getting closer to having a ridable 750 Comando. Have been thinking about it and would consider changing to Mikunis or better yet also going to a single. Would enen consider a single Amal.

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I encourage you to discourage yourself from this thought.

A properly set up pair of Concentrics works great, looks right, and will outrun a single anything. A pair of the new Concentrics corrects the slide/body wear that occurred with the originals (as does a sleeved pair of originals). I have been running a set of sleeved originals since 2006. The bike will idle smoothly at 600 RPM and will walk off and leave a single Mik bike at around 60-65 MPH.

MexicoMike said:

I encourage you to discourage yourself from this thought.

A properly set up pair of Concentrics works great, looks right, and will outrun a single anything. A pair of the new Concentrics corrects the slide/body wear that occurred with the originals (as does a sleeved pair of originals). I have been running a set of sleeved originals since 2006. The bike will idle smoothly at 600 RPM and will walk off and leave a single Mik bike at around 60-65 MPH.

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I agree with everything you say but a single Tm40 pumper can not be compared to a single Vm mikuni ,I'd be amazed if twin concentrics would pull away from a single TM 40 the TM really starts to work above 5000rpm just as a VM starts to lose power ,the two setups are like chalk and cheese,
Only problem with a TM is you need to notch the gusset in the frame to make it fit but it's a small sacarafice for the performance it brings

I don't know anything about a Tm40 so it might work great though overall, with a single carb manifold I wonder if the flow characteristics would match the twins. The flow reversion wave would act very different feeding back into a single carb than it does with dual carbs. But I'm sure there have been some sort of objective tests done - dyno or 1/4 mile trap speed - that would demonstrate how well the Tm40 works compared to a pair of concentrics. The only thing I'd suggest re this is to NOT rely on a "butt dyno" to verify power. It is frequently wrong and often confuses a "hole' in the power curve with increased power.

FWIW, with auto motors we used to see that quite often when someone installed a carb that was too large for the application. They would talk about how they could "feel" the increased power but what was actually happening is that the power curve was flattening compared to the OEM setup and then the engine would, as RPM increased, come up out of the flat spot and accelerate "normally." That acceleration seemed impressive BECAUSE of the hole in the power curve. A dyno would show the hole and a track test would show the trap speed to be lower than it was with the OEM carb. The butt dyno also inevitably feels more noise as more power - common with aftermarket exhaust systems that typically ONLY add noise and often add noise AND reduce power. We did a bunch of dyno tests on Harleys with straight pipes and they all produced less power than the bike did with the stock pipes. Sorry for digressing so much but aftermarket parts and their marketing claims are a pet peeve of mine...

NOT saying aftermarket parts are bad; it's some of the claims they make - "Bolt on 'X' HP" - that gets me going...

It would be great to put my bike fitted with standard concentrics then the single TM on a Dyno just to see the difference as you say it can be deceiving ,
My bike pulls from tickover to way past 7000rpm if I let it,
I had to make my own inlet manifold it has a steeple in-between the inlet ports cheers

I've tried both to say ya must be jerking WOT habitually from off ilde to power peaks to tell the difference. To me 2 Amals are a tad more responsive to mid range but in my 2 Cambats case 34 mickey mouse pulled better to higher top out than 2-32 Amals. Likely maxing out tire wasting racers may want the dual carbs but otherwise the decision really boils down to looks and/or ease equal mix of single - which does have air filter fitting issues. Its a fickle forum, so will get flack form sticking with/nursing obsolete stuff as well as 'ugprading' away from factory numbered parts. I'm a spare 34 micky carb kit with choke-enricher cable to lend for test/feedback or sell if like it - as ani't a factory part for Trixie and ain't nearly enough for Mz Peel.

If you change from twin carbs to single carb or vice-versa and use identical jetting, you might be expecting too much if you think the carburation won't have flat spots. The vacuum conditions have to be different with a branched manifold when compared with two separate tracts.