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DavidP Offline OP
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Why did they make these so long and strong?
Seems to me that being able to open the choke slides completely is more important than keeping them at the bottom for starting. As someone who always trims a couple of coils off these springs just to make the lever stay in place, I ask WHY?


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Shortening coil springs means more effort to compress a given length


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Originally Posted by Andy Higham
Shortening coil springs means more effort to compress a given length

Are we all getting a bit bored? I should be outside doing much neglected yard work, but it's too friggin' hot. So I'll bite:

If the spring is already under a bit of tension in the choke slide in its most relaxed position (down), then cutting off a couple of loops would allow the rest of the spring to lengthen a bit, thus reducing the pre-load. In the "up" position, there is less spring spanning the available (fixed) length. This would thus reduce the tension on the spring. Andy, I think you may have meant shortening a coil spring by compression, as in increasing the pre-load on struts.

But this is something I wouldn't mess with; the whole setup is finicky enough as it is. If the spring washer in the choke lever is in good shape and the lever is properly tightened, this should keep the chokes from creeping down.


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DavidP Offline OP
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Originally Posted by Mark Z
But this is something I wouldn't mess with; the whole setup is finicky enough as it is. If the spring washer in the choke lever is in good shape and the lever is properly tightened, this should keep the chokes from creeping down.
Spoken as a man who only needs to keep two chokes open.
Maybe with a little less tension I would be able to replace the single cable without disassembling the whole shebang to get it out of the splitter.


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Clean the choke lever friction brake, grease is not good for it, once you have a setting that holds the choke open, loctite the centre screw in position.If it still wont work , add more friction, , scuff the rubbing parts with 100 grit paper, rebuild , keep grease off the rubbing parts.
Andy is right, so is Mark, cutting two turn off will reduce the pre load a little, once it starts to move it will behave like a stiffer spring, a spring with more turns is softer than a spring with less turns for a given length and diameter.


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Thanks,
I got the cable replaced using a little trick I dreamed up.
Remove the air cleaner. Hold the throttle open and insert a socket into each carb to hold them open. Pull on each short choke cable and push the socket further in to hold them open. That results in enough slack to replace the single choke cable. Then remove the sockets.
Saved having to remove the whole assembly.


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A lot of new choke levers come with the spring the wrong side of the lever, if yours is constantly trying to close on its own then swap its position. It’ll be fine after that. Worked for me anyway.


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Originally Posted by DavidP
Spoken as a man who only needs to keep two chokes open.

Oops, forgot you have a triple. Worse yet, I run Mikunis on my A65. But I USED to have chokes!


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Cutting coils of the springs makes them stiffer but with less preload. Might be a trade off there but never had a problem with the lever holding them up.
Even easier method is to wind down the cable adjusters on the carbs then up each cable up and lock a pair or forceps on each cable. No need to remove the air cleaner and have three same size sockets.

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Whats a choke? laughing

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Originally Posted by Mark Z
Oops, forgot you have a triple. Worse yet, I run Mikunis on my A65. But I USED to have chokes!
I looked at Mikunis from MAP. Less expensive than the Premiers. BUT, then I'd have three separate throttle cables. crazy

I thought of using locking pliers on the cables, Dave. But I only own two roach clips, er hemostats.
The sockets don't need to be all the same size, just big enough to get the job done. I needed the air box off to adjust the choke slides anyway.


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i have found that stock AMAL throttle cables and twizt grips work fine in mikunis

but for the T150 you will indeed have to use a splitter

barnett can make anything you want but they dont have patterns for everythin so working from an example is best


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Originally Posted by DavidP
Originally Posted by Mark Z
Oops, forgot you have a triple. Worse yet, I run Mikunis on my A65. But I USED to have chokes!
I looked at Mikunis from MAP. Less expensive than the Premiers. BUT, then I'd have three separate throttle cables. crazy

I thought of using locking pliers on the cables, Dave. But I only own two roach clips, er hemostats.
The sockets don't need to be all the same size, just big enough to get the job done. I needed the air box off to adjust the choke slides anyway.

Mikunis cheaper than AMAL Premiers, really? Last time I looked, Mikunis were over $200 each; maybe the price has come down.

Ok, now that we've taken the thread in a different direction: If you're seriously considering a carburetor swap, how about some JRC's? Same size and fittings as your AMAL MK1's, and enrichening circuits instead of chokes, like Mikunis.


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I’ve always known mikunis to cost less than AMAL’s, but if they do cost considerably more (it’s about 15 years ago since I bought a set and sold them on) then why not look at the bigger brother version of the Mikuni vm.... the AMAL Concentric mk2


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Originally Posted by Allan G
I’ve always known mikunis to cost less than Amal’s, but if they do cost considerably more (it’s about 15 years ago since I bought a set and sold them on) then why not look at the bigger brother version of the Mikuni vm.... the Amal concentric mk2

niche cycle in america sells 32mm AMAL mk2s for US$245 each.

32mm VM round slide mikunis go for US$112 each

32mm TM flatslide mikunis are US$173 each.

lowbrow customs sells 30mm JRC carbs for US$113

i switched back and forth between 26mm mark 1 Concentrics and 26mm VM mikunis on my T150. the mikunis were much easier to mount and tune (because, mikuni . . .) but i was never satisfied with the enrichener circuit. you have an adjustable choke on the Concentric. th emikunis just have a non-adjustable toggle. you can adjust them with a drill bit, i'm told, but its fussy and if you go too far youve gone too far


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Yes, I much prefer the Mk2's I have on the Bonnie. I use a dual twist grip and separate cables for them.
However, one of my big considerations when choosing the Premiers for the Trident was retaining the throttle gantry with only one throttle cable and one idle speed adjuster.
Too bad they don't offer the same set with Mk1.5 carbs, with the enrichment circuit.


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my mikunis used a three way splitter just like the one on the triplez choke. with a cable adjuster on each cable it worked fine and waz vastly simpler to adjust than the gantry.

with the gantry synchronizing the slides is a disassembly bench job. with the mikunis you just stick a zip tie under each slide and adjust until it wiggles the same in all three


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