Mikuni Choke Position

That is the only slight niggle I have with the Mikuni, the lever is so far in tucked away under the fuel tank that I can’t reach it unless I’m knelt beside it to find it. A cable or even a longer lever maybe a good thing.
On one of my race bikes, a single, I have drilled a small hole in the end section of the lever and used a length of locking wire twisted into a pigtail and hanging down far enough to grab from below and pull!

'Choke' can be turned off by pushing up on the lowered lever, or if access is better, pushing down on the top of the choke mechanism on the right of the carb!
 
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Bastard to use on the left carb though! (I'm told!!)

Yes, but a Commando would normally have a single Mikuni.
The picture (not of a Commando) was only for demonstration purposes as there's nothing wrong with any of the three lever mechanisms. ;)
 
Yes, but a Commando would normally have a single Mikuni.
The picture (not of a Commando) was only for demonstration purposes as there's nothing wrong with any of the three lever mechanisms. ;)
In which case....the one in the middle is probably even harder! ☺️
 
Can you point us towards a source, please.
I did, I gave you the Motocarb part number! They are about £16 for the carb end bits.

'Mikuni sell the parts you need to fit cable operation at the carb. MK- 412 from Motocarb, maybe other numbers elsewhere. 1 kit per carb.'
 
In which case....the one in the middle is probably even harder! ☺️

But then the choke lever assemblies could always be changed over (or complete carbs swapped over as all three are identical). :)
 
I understand that works, and I understand it is probably useful, as long as you don't leave it there too long, but it isn't really what Mikuni (or Amal) intended!

Using the fuel enrichment lever raises the rubber seal used in the mechanism off of the fuel way orifice/seat.

There are only two intended positions, on the orifice seat and off the seat, no enrichment fuel flow or enrichment fuel flow. Start up, warm up, close orifice!, ride away. So no riding with fuel enrichment on.

The 'choke' is either held with the orifice closed for normal running, by the internal coil spring, or held off of the orifice by the external detent spring (part 15 referenced earlier) for starting.
Yep I agree with how the enrichment mechanism works
I can only tell you from personal experience that with the lever fitted to my t140e you'd flick the lever on
Kick the bike over
And it would start and rev to approximately 3800 rpm
If you turned the lever off before the engine had fully warmed up it would cut out and stop
With the cable conversion I could start the bike and I could bring the revs down to 1500-2000 rpm whilst the engine was warming up
If wanted I could ride to the end of the alley to the road about 200yards before turning the enrichment off completely
 
On my t160 I have triple mikuni VMs
The middle lever is a little fiddly to operate
I generally push the 3 levers down then flick the two outside ones off then push down on the plunger on the middle carb to release it
 
Yep I agree with how the enrichment mechanism works
I can only tell you from personal experience that with the lever fitted to my t140e you'd flick the lever on
Kick the bike over
And it would start and rev to approximately 3800 rpm
If you turned the lever off before the engine had fully warmed up it would cut out and stop
With the cable conversion I could start the bike and I could bring the revs down to 1500-2000 rpm whilst the engine was warming up
If wanted I could ride to the end of the alley to the road about 200yards before turning the enrichment off completely
The fuel enrichment on my Norton with twin Mikunis starts the bike effectively, but doesn't run ridiculously high, and yes, if you turn it off too soon, it stalls. I normally turn off the left and wait a few seconds before turning off the right, do it too early, it stalls. I normally judge based on how much popping and banging is going on! :cool:
 
It's even worse trying to get to the right carb with a twin Mikuni setup, unless you use the link bar set up from a Suzuki (say GT500).

Mikuni sell the parts you need to fit cable operation at the carb. MK- 412 from Motocarb, maybe other numbers elsewhere. 1 kit per carb.

Single Mikuni should work fine with an Amal style handlebar lever and a single carb choke cable.

(I have these parts on a twin Mikuni set up and have used Yamaha TR/TZ cables and one of Don Pender's thumb chokes, but you need to keep your thumb on it until the engine is warm enough to let the choke off)
The link bar was a lot better on a Suzuki t500 because the inlet rubbers were much firmer than on a triumph t140e that had the problem of the carbs pulling together instead of opening the right enrichment jet as you used the lever
 
My race CB250 will not start if not using the left enrichener. RH carb lever impossible to reach. Needs 3-4 minutes warm up before flipping the lever.
The Venom Clubman with a Mikuni has a handlebar lever. Don't know how PO fixed it. Enrichener totally inaccessible without removing the carb.
 
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That is the only slight niggle I have with the Mikuni, the lever is so far in tucked away under the fuel tank that I can’t reach it unless I’m knelt beside it to find it. A cable or even a longer lever maybe a good thing.
Agreed. After reading through this I took the lever assembly off and attached a short extension piece to it, angled it down slightly and now it's much easier to locate.
Thanks for the motivation.
 
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