Cold Blooded

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I have a 1973m 750 with single Mikuni. Upon cold start I have to use choke and it needs to warm up significantly before riding away. If not it will stall easily if not very careful on the clutch and throttle. Anyone else experience this? Any possible ways to reduce this effect or eliminate it? Or should I simply let it warm for a minute or two before riding away?

Thanks in adance.

Steve
 
I have found that the very assessable and easy to use idle screw works for me. I simply reach down and give it a flick when cold, maybe a half turn, enough to idle and usually by the first or second stop sign I just reach down and turn the idle down to suit.

What i would NOT do is let the choke/enrichener (or what ever the nitpickers want to call it) stay on and load up the cylinders/head. This could have an adverse effect over time with carbon build up.

That being said, you may need/want to fiddle with you idle curcuit (air screw) and maybe adjust the pilot jet. I should not tell you that I run a #40 because this may only serve to confuse as these units are quite proprietary to each bike that they serve. But there you have it.
 
Hi,
have same set up with similar issue at cold start. What I do after starting is of course choke off after about 1/2 minute running then I reach down and adjust idle with screw on left side of carb by turning screw inwards clockwise to increase idle to around 1200rpm so I don't have to hold throttle grip. I can leave like that and by the time I get a block or two up the road machine is warmed up enough I then readjust idle again to around 1000-1100
Doxford
 
Get off the choke as soon as possible because all that gas is "washing" the cylinder bores of oil at the time that they need it the most - cold startup. The Mikuni choke passage dumps too much fuel into the motor generally speaking and there can be fitted a jet sizing arrangement into this passage to lessen that flow a bit.
 
Same old problem - the usual issue is that the Pilot Jet is undersized, typically on a VM34 carb it must be either .35 or .40 check that first and fit either and the bike will start on choke, warm up for 30 seconds, turn off the choke and ride away without any hesitation or stumbling.

Mick
 
Hi steveyacht, How are you getting on ?
Typically, ...If your Air screw is less than 1 turn out, your Pilot is too lean ( small ) and by turning the screw out further you are just leaning things off more.
If your Air screw is more than 2 turns out, your Pilot is too rich and turning the screw out any further won't realy help.
AC.
 
Thanks for all the suggestions. I am running a #40 now and once warmed up she runs like a scalded cat (faster than scalded dog). Just having problems with the initial start. I will try the idle screw suggestion and see how it works this coming weekend at the bike rally here in Myrtle Beach.
 
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