choke question

'70 750...doesn't seem to have much effect. idle doesn't increase when the lever is moved. if all the way closed, the bike seems to hesitate a bit when under laod (accelerating) moving the lever seems to help with that. do i need to take the tank off the mess with it at the carbs, or is there a quick and simple way to check/fix it?
thx, goo

Yes there is. It's called removing the choke system entirely. People often confuse the handlebar lever positions regarding on or off. When you remove the cables where they enter the carb tops the holes must be sealed up. Just tickle to start cold. The lever is real cool looking though.

I completely removed the chokes from my Amal carburetors, and it starts just fine without them, just takes a few more seconds to warm up. Cleanded up the handlebars, too, by getting rid of the lever.

Goo
During the summer riding the choke is of little value. During colder days it is good for start up and I will pull it off once I am out of the driveway and down the road. I like the choke in the bike because you can use it for emergency if the throttle cable ever breaks. Especially if you are on a trip far from home on a Sunday when bike shops or parts dealers are not open and guaranteed that you don’t have a spare one in your saddlebag.
My two cents.
CNN

How about this ? Retain the very cool looking choke lever with a cable attached to it that feeds under the tank to nothing whatsoever. Looks good and cable is there in a pinch. My 2 cents worth.

I'll agree the air control on mine doesn't do much, however I left it on. I do use it to start out of habit, now if it helps, I don't know. I do know if I leave it on, it still runs fine, however when accelerating hard, it stutters. I rode all the way home that way once wondering what was wrong. It may make a difference if you ride in the winter.

It sounds like you may need to go through the Amal tune up, they have a running setup on their site. What are you using for main and needle jets?

Dave
69S

Mileage on those carbs ? Plug colour and age ? Slide-sloppage in bores leading to slide-fracture ? Fuel inside floats ? Old float needles ? Warped bodies from overtightening ? Warped bowl screw flanges ? Lack of lube in choke cables ? Finally , Goo gassy goo in pilot jets. Whew !

Re: your original question, the only thing you can do without taking the carbs or float bowls off is adjust the idle pilot and the idle stop. If you take the float bowls off you can adjust the float level, and even get to the main and needle jets, but not the needle itself. But I usually do that with the carbs and tank off. You will get sick of that nylock on the front tank studs.

Dave
69S

thanks for the inputs, gents.
the problem may be moot. i just recieved my mukini single carb. as soon as i work up the courage to remove the amal and replace it with the jap unit i'll post results.
..
any suggestions on this project?

goo said:

thanks for the inputs, gents.
the problem may be moot. i just recieved my mukini single carb. as soon as i work up the courage to remove the amal and replace it with the jap unit i'll post results.
..
any suggestions on this project?

Click to expand...

Did you get a Mikuni Kit with manifold and filter pre-jetted for your bike from a dealer who set it up?
If yes you should have a pretty easy go of it. Install and try it out.
It should have come with instructions for adjusting carb.
No tickling required or even optional on this carb.
Remember Mikuni doesn't have a choke but a seperate circuit that when the lever is up acts to provide a fuel rich air supply.
It only works when throttle is completely closed and don't crack it when engine first fires or you'll put out the fire.
I use my "choke" most of the time up to maybe 60 degrees. If no choke maybe 1/4 throttle.
There is an adapter kit that provides a cable from the "choke" to the standard handlebar lever. I like it a lot rather than have to fiddle with the carb with my hand during fire up.
I had a problem with my Mikuni staying stuck full open. Lucky to have a kill switch as I was going 70 at the time and winding up in third gear!
Pulling clutch would have blown engine for sure.
After stopping and checking everything was ok. Apparently high velocity air flow is able to hold slide up.
I found out on this forum that this had happened to others with the 34mm VM. Solution others used that I did was to add an Amal spring in addition to existing Mikuni spring. Makes throttle a little stronger but not a problem but hasn't stuck since.

Yes to adding the extra spring strength for twisting. The Mikuni is too soft for my liking ,but has it's advantages, downside , made in Japan. Airigatu Godzilla.