Choke operation and function, how does yours work?

MB-Ian

Melbourne, Australia
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My B has a 750 big bore kit, rephase, pamco and VM34 roundslides. It starts easily enough with both carbs choked, on the kick or electric starter, when stone cold - the revs rise to about 3000 then work their way down until the thing eventually stalls (over the space of less than a minute). If i turn one of the chokes off and blip the throttle the engine will warm up and once its warm it runs well, but this warming up gives me the shits.. keeping it from stalling... my starter motor and battery are pretty jack of it as well..

Is everyone elses XS the same and this is just what they're like or is mine being more difficult than it needs to be?

By comparison a mates ninja with carbs you just pull the choke, start the bike and it idles around 1000 rpm, and works its way up to 2000 revs... by the time its idling at 2500 rpm on the choke you can pretty much turn the choke off and start riding... no stall-outs etc. Alright its a modern bike but still...

I'd ideally like to be able to start my XS and, like most of us, while its warming up put on me jacket, gloves, helmet, and start riding without having to turn chokes off while travelling at 40mph... or am i just asking to much of the old girl?

I.
 
I turn on the choke to get it started, then turn it off after about 30 seconds and blip the throttle for about 30 seconds more, then take off.
 
I put on my jacket, helmet etc, put on the choke(if cold), kick it and ride off. After 1/2 a mile i take off the choke, no worries.
I Don't expect the bike to idle for long periods, not even at redlights.
You can't compare with a modern 4cyl bike like a ninja...
 
Stock carbs cold, full choke, start run till she starts to blubber, half choke fiddle for 1500 -2000 rpm, helmet gloves etc. ride off, finish shutting off choke in a couple of blocks. The heritage with the bar mounted choke is nice. A 1/2" piece of plastic tubing on the idle stop screw as someone on here suggested is a nice addition, makes it easy to fine tune the idle as conditions dictate.
 
Warm day no choke is needed unless bike sat a long time. Then it is just for the first kick or so. Once started it goes full off. Most of the weather here in South Florida can be pretty warm so it does not need lots of choke, actually fuel enrichment.
 
My procedure is like Gary's except it's half choke then quarter. Start with full only if it's very cold, like around freezing and start at quarter only if it's a warm morning or been sitting awhile. And I do hat and gloves before starting, In detail, it's hat while still inside the house, lock the door carrying gloves, put key in igntion and and turn to non lock, then put gloves on, and finally start bike. :)
 
I don't know much about the VM34 RS carbs. It sounds like your pilots or air mix screws or choke needs a bit of tuning. Grizld1 is the one to talk to.
 
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So its sounds like I've got the choke worked out, this is as good as it gets and there's no problem riding the first km or so with the choke on or half on.. The PO said he didn't like to ride with the choke on and warmed the bike for a long period before riding but then again he was much older than me and retired so probably had more time on his hands.

Lately I've changed the starting sequence so that starting the bike is the 2nd last thing I do (before my hat) after I've put on the jacket, gloves, backpack, locked house and opened garage door.

I.
 
I had a car with a manual choke that came with detailed printed instructions that included shutting off the choke after driving some distance, so I never thought twice about driving the xs with the choke on. Beginning chokers think of the choke as an on/off thing but it's actually an art form.
 
I as well as others, wheel the bike out of the garage. Start the bike. Put on our gear. While watching the idle, Ease the choke off if to high. I have a plastic valve cap on my idle screw, this makes adjustment easy. If the idle is slow adjust it up.
By now if you can feel the right side cover and it should feel a bit warmer than before starting. If so, ride it gently for the first few miles. If not let it warm a bit more.
You want the oil warmed enough so it flows to all the places oil needs to go.
If you just fire it up and ride it hard some parts may be oil starved for the first few miles.
It's your bike, do as you feel is right.
 
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