Mikuni twin carb kit (2014)

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Mikuni twin carb kit (2014)


Has anyone experienced this Mikuni VM34 carb set on a Commando ? Looks very promising apart from the filters that seem ridiculously narrow and almost impossible to breathe!?
 
yes - i have them on my 750 and i love them - but my setup has slightly more splayed out manifolds (or at least they appear to be compared to those in the photo - like these

http://www.ebay.com/itm/NEW-NORTON-ACK- ... a6&vxp=mtr).

once setup the bike runs great - if you do get one the the victory mikuni for british twins pamphlet can a great help to dial them in and help save a bit of time if your unfamiliar with mikuni's (or just want some interesting reading)

i used uni filters on mine - they work well too
 
Thanks Mikegray660, I think I will try the Mikuni set in combination with velocity stacks or at least longer filters!
 
How are the two carbs going to sit side by side with those bloody great big air filters on them? I once tried to put the conical air filters on a pair of Amal Mk1s, and there wasn't even enough room for those.

[Edit] Ignore that. I've just noticed how eccentric the filter to carb connection is.
 
nortonspeed said:
.....Looks very promising apart from the filters that seem ridiculously narrow and almost impossible to breathe!?
Click to expand...
A friend has his bike on the Dyno with a single Mk II which was initially fitted with one of those pancake filters - it was definitely strangling the airflow on a single carb.
 
mikegray660 said:
yes - i have them on my 750 and i love them - but my setup has slightly more splayed out manifolds (or at least they appear to be compared to those in the photo - like these

http://www.ebay.com/itm/NEW-NORTON-ACK- ... a6&vxp=mtr).

once setup the bike runs great - if you do get one the the victory mikuni for british twins pamphlet can a great help to dial them in and help save a bit of time if your unfamiliar with mikuni's (or just want some interesting reading)

i used uni filters on mine - they work well too
Click to expand...

Just out of interest, what jetting setup did you end up with? Was it close to the Victory manual settings?

I have a pair of VM34s, and some of those manifolds, but I am using them on a Rickman with different manifold on a 750 Shorts Stroke, it is a race bike, so will differ considerably from what you will be trying to achieve I think. I got one recommended jet set up from a guy on here who also has a short stroke racer, it is very different from the VM book. I don't yet know what is going to work in mine.

I got the carbs from a guy who ran them on a road bike both with filters and with stacks. I think he tried a lot of settings, but it seems he never really got it fine tuned to his liking, but he never told me if it was an off idle or top end issue for him.

I sort of assumed he had little experience of detailed carb set up and was having trouble off the bottom looking for road bike finesse at smaller throttle openings. He stayed with the VM manual identfied needle and tried a bunch of needle jets, pilot jets and a couple of slides and only a few main jets.
 
The kit in the picture looks like the one for Triumphs. I don't think you can fit any of Mikunis to a Commando without splayed manifolds. Then again, I could be wrong, but I have run Minunis on Commandos with the splayed manifolds, and it sure doesn't look like they will fit without them.

Ken
 
Steve

my settings were slightly different than the victory manual , but my 750 has 10:1, headwork, and a 2S cam

pilot 30
slide 2.5
159 needle
p6 jet
6DH3 needle
250 main
.7 airjet
clip in 4 from top

it was unclear if a 1.0 or .7 airjet made any discernible difference but plugs looked a bit better with .7



SteveA said:
mikegray660 said:
yes - i have them on my 750 and i love them - but my setup has slightly more splayed out manifolds (or at least they appear to be compared to those in the photo - like these

http://www.ebay.com/itm/NEW-NORTON-ACK- ... a6&vxp=mtr).

once setup the bike runs great - if you do get one the the victory mikuni for british twins pamphlet can a great help to dial them in and help save a bit of time if your unfamiliar with mikuni's (or just want some interesting reading)

i used uni filters on mine - they work well too
Click to expand...

Just out of interest, what jetting setup did you end up with? Was it close to the Victory manual settings?

I have a pair of VM34s, and some of those manifolds, but I am using them on a Rickman with different manifold on a 750 Shorts Stroke, it is a race bike, so will differ considerably from what you will be trying to achieve I think. I got one recommended jet set up from a guy on here who also has a short stroke racer, it is very different from the VM book. I don't yet know what is going to work in mine.

I got the carbs from a guy who ran them on a road bike both with filters and with stacks. I think he tried a lot of settings, but it seems he never really got it fine tuned to his liking, but he never told me if it was an off idle or top end issue for him.

I sort of assumed he had little experience of detailed carb set up and was having trouble off the bottom looking for road bike finesse at smaller throttle openings. He stayed with the VM manual identfied needle and tried a bunch of needle jets, pilot jets and a couple of slides and only a few main jets.
Click to expand...
 
When I ran dual VM34 Mikunis a long time ago the manifolds were made by ACK. The carbs will need to splay out.

Found a new pair of ACK manifolds on ebay while Googling this morning but hard to tell what they look like under the wrappings. See http://www.ebay.com/itm/NEW-NORTON-ACK- ... 4734wt_915

Ended up back with resleeved Amals. Wasn't happy with the low end and midrange rush with the dual Mikunis.
 
lcrken said:
The kit in the picture looks like the one for Triumphs. I don't think you can fit any of Mikunis to a Commando without splayed manifolds. Then again, I could be wrong, but I have run Minunis on Commandos with the splayed manifolds, and it sure doesn't look like they will fit without them.

Ken
Click to expand...

I am sure you are right Ken, When we made the manifold for my Rickman, even though the frame allows you to go parallel, the size of the carb bodies (VM34) don't allow that. So my manifold whilst a simple plate and a straight tube for each carb, does have a splay outward to the carb end, but since the manifold is longer it is not so severe as the cast alloy Commando versions.
 
batrider said:
Ended up back with resleeved Amals. Wasn't happy with the low end and midrange rush with the dual Mikunis.
Click to expand...

can you explain the problem a bit more please?

What was the low end issue, on and off throttle of just lumpy?

May just be a language problem but I am not sure what you mean midrange rush? Is this a lack of it or too much (surely there can never be too much midrange :D )
 
It was not as fast in the low to midrange RPM region. Could not make the front end feel light or non-contacting the ground when accelerating in 2nd gear. Was good on the top end.
 
I had the Mikuni VM32 kit on my Mark 3, which were installed by the previous owner, prior to me buying the bike.

I realized soon after the purchase (was a long distance deal) was the bike was smoking and the Mikunis were both left hand carbs, which meant i could only reach the choke lever for one carb to start the bike, which was a hassle. I called the PO to ask about this curiousity, and he said he bought the kit used on ebay and just bolted it on with no adjustments.

Given the choke lever hassle and the smoking issue (still undiagnosed) i decided to simplify my life and switched to the single Mikuni VM34 kit. Bolted it on more than 5 years ago and haven't given it another thought since.

However, I keep thinking about going back to twin carbs, Mikunis not Amals.

The correct kit(s) for the Commando are on the Sudco site: http://www.sudco.com/carbkits.html
001-250: pair of VM32 carbs
001-251: pair of VM34 carbs

The correct air filters are K&N RC-2340
The above are available from various vendors, including Rocky Point Cycle, OldBritts, etc.

Good luck.
 
there is a right hand and left hand version for minuni VM carbs and a sort of "cross over" for the choke for each side to get to them easily 9the choke levers) - or you can make them cable operated easily enough with an after market kit (avaiably at a few vendors) and won't have to f'with the levers on the carbs themselves

pkeithkelly said:
I had the Mikuni VM32 kit on my Mark 3, which were installed by the previous owner, prior to me buying the bike.

I realized soon after the purchase (was a long distance deal) was the bike was smoking and the Mikunis were both left hand carbs, which meant i could only reach the choke lever for one carb to start the bike, which was a hassle. I called the PO to ask about this curiousity, and he said he bought the kit used on ebay and just bolted it on with no adjustments.

Given the choke lever hassle and the smoking issue (still undiagnosed) i decided to simplify my life and switched to the single Mikuni VM34 kit. Bolted it on more than 5 years ago and haven't given it another thought since.

However, I keep thinking about going back to twin carbs, Mikunis not Amals.

The correct kit(s) for the Commando are on the Sudco site: http://www.sudco.com/carbkits.html
001-250: pair of VM32 carbs
001-251: pair of VM34 carbs

The correct air filters are K&N RC-2340
The above are available from various vendors, including Rocky Point Cycle, OldBritts, etc.

Good luck.
Click to expand...
 
batrider said:
It was not as fast in the low to midrange RPM region. Could not make the front end feel light or non-contacting the ground when accelerating in 2nd gear. Was good on the top end.
Click to expand...
Are you saying that the amals flowed better from lowdown through midrange to deliver more power?
 
I'm a Mikuni lover and have either single or dual carb set ups on all of my Brit bikes both Triumph and Norton . Mikunis are not a plug and play deal even if you buy the Kits available. I was surprised to read that one fellow's Mikuni set up lacked bottom end and mid range. It's all in the tuning. It's trial and error to some degree to find the exact set up for your particular bike. Once you find it ,it's well worth the trouble. I go so far as to not only play with jetting (needle jet,jet needle,main) but I'll also start with a "richer" slide and machine off a 1/32 of an inch at a time to get the slide to give me instant response. Go with the Mikunis,but be prepared to spend time tuning....Skip
 
I fooled with the jets over a 3-4 year period when I had them on and saw improvement. They ran well but just did not have the same kick. It may have just been that they were 34mm and the stock carbs are 32 mm. Also I was in a mode where I wanted everything back to stock looking.

Not anti-Mikuni. Just don't like 'em on my bikes.
 
With twin 34s it must have flown on the top end. I actually have a pair of 34s on a 750 Bonneville and it's a powerhouse.....but uses a ton of fuel!
 
I have had dual 34 Mikunis on my MKII for decades, and dual 32s on a MK III. My bikes need flexable filters like Uni Filters to go between the frame raile. Both carbs are left. On one bike, I turned the lever around. On the other I didn't bother. Complaining about which side the choke lever is on and using ticklers is akin to gagging on a gnat while swallowing a camel. Not that I mind tickling the Amals, but you can reach both choke levers even if you don't turn the right one around. The cable ends are what bother me.
 
I tried a pair of mik vm32’s on my 750 more than ten years ago now , used the uni filters as well , made up my own cables and it was painful ....the splayed mounting was no good for me and removed them and back to single vm34 at the end of that season .... the pair of 32’s did not disappoint in improved performance , although I did go through more fuel , wish they had fit more out of my way ....
 
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