Hard to Cold Start (2011)

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Could be, however Lorenz reports that after all of this kicking the plugs are still dry.
Dry plugs do not happen with flooding.
I agree that there is no reason to kick the bike over with ignition off.

Glen
 
1up3down said:
kick with the throttle partially open, this will raise the slide and allow the richer mixture to be drawn into the combustion chamber versus keeping the slide down will mostly just back up the richer mixture.
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It's important to keep the VM carb throttle closed for cold starting. Opening the throttle WEAKENS the mixture as less mixture will be drawn in through the starter circuit.

http://www.mikuni.com/pdf/vmmanual.pdf

"3-4, Starting device (starter system)...
.
.
.
Since the starter type is constructed so as to utilize the negative pressure of the inlet pipe, it is important that the throttle valve is closed."
 
I understand that LAB, and I cannot refute the theory, but IF his bike is hard to start keeping throttle closed then he has nothing to lose by kicking with it open does he?
This technique has worked very well for myself for the 25 years I have my Mikuni.
However, it is also possible his cold starting could be also solved by keeping the throttle closed but not kicking it multiple times with choke on and ignition off.
What he is doing is clearly not working, what I do works flawlessly, regardless of what the Mikuni manual says.
 
1up3down said:
I understand that LAB, and I cannot refute the theory, but IF his bike is hard to start keeping throttle closed then he has nothing to lose by kicking with it open does he?
This technique has worked very well for myself for the 25 years I have my Mikuni.
However, it is also possible his cold starting could be also solved by keeping the throttle closed but not kicking it multiple times with choke on and ignition off.
What he is doing is clearly not working, what I do works flawlessly, regardless of what the Mikuni manual says.
Click to expand...

The usual problem with the Mikuni VM cold start circuit is that it can be very rich and will flood the engine after a few kicks. Opening the throttle can then help the engine to fire as it leans off the mixture, however, an excessively rich mixture doesn't appear to be the cause of the cold starting problem as Lorenz said:"The plugs are NOT wet once I check them after 4-5 kicks.."
 
yes he does say the plugs are brown when the insulator should be more whiteish?
good chance just putting in new plugs may help starting but I lean more towards kicking right away with ignition on, choke on but throttle partially open
 
DogT said:
Put the Amals back on. Tickle and start.

I know that's cruel.
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Funnily enough that's exactly what I have had to do with my commando
My knee is shot and I only have a few kicks in me
And my bike wasn't a 100% starter with the TM 40
I have had to revert back to twin amals that I can tickle for a first or second prod of the kickstart but since then I have spent a lot of time on the amals getting them to run spot on ,I can't honestly fault them
 
I'll tell you guys what, I can't remember the last time I started the Norton, it's been at least a year. It'll be snowing and ice tonight supposedly, so tomorrow after wake up, I'll back the car out of the garage, get the bike in position and see what it takes to start it. And I've got stenosis in the back with half asleep legs and my feet feel like they have ropes in the balls of the feet. 75 years at this point. But I'm supposing I'll start it on about the 2nd or at most the 3rd hit. It's usually like that, but it's got avgas in it. That helps. I'll report tomorrow. Now I've set myself up.

Strewth, I had to look that up!
 
Where do those ropes in the bottom of the feet come from?
I'm 64 and they showed up over Christmas.
Put in just over 400 pressure treated posts and built just shy of a mile of horse fence last year. I thought I was invincible and now I'm paying.
At least the Commando has a working estart!

Glen
 
DogT said:
Put the Amals back on. Tickle and start.

I know that's cruel.
Click to expand...

No Joke: I have 2 pcs. Amal here on my desk, unfortunatelly no mainfold.
Also a AMAL MKII 34mm single carb.
I go cracy by this Mikuni.
Some say: Throttle closed, other say: 1/3 open.

Friends: I've tried EVERYTHING, really!
Last night I have open the mikuni and cleaned him again. I checked the cold start bypass, blow him out. So I will check today the start bahavior.
Due I have disassemble the filter I can inject a bit gas in the intake.

But I swaer: I DON'T give up... by the end of this nightmare I will have a good starting NORTON.
 
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Blowing through may not be enough.

On one I had a while ago, the jet that LAB showed was partially blocked with quite solid material, it needed removing and ‘poking out’ to clean it.

The poking probably damaged it... replacing would perhaps be a better option.
 
1up3down said:
yes he does say the plugs are brown when the insulator should be more whiteish?
good chance just putting in new plugs may help starting but I lean more towards kicking right away with ignition on, choke on but throttle partially open
Click to expand...

Point is: Yes, the plugs are brown, means after I was 30 - 40 minutes on the road.
I have used a leaner jet, but then the bike does not accelarate propper. By the current setting the bike runs really nice, OK, may I can use a bit leaner mai jet, but this does not have influence in cold start as I learned by this forum.

And folks: Thank you to all of you for this kind help and effort! :)
 
Fast Eddie said:
Blowing through may not be enough.

On one I had a while ago, the jet that LAB showed was partially blocked with quite solid material, it needed removing and ‘poking out’ to clean it.
Click to expand...
I blow out, use brake cleaner, check it with a small wire. Once I spray in the brake cleaner ite will flow into the bowl immediate.
I guess this way is not blocked anymore!
My neighbour ask me to buy a propper NEW bike when he saw me in the garage. The Norton is to loud and to old he explained.

Not for me, I said, not for me! :D
 
Lorenz,

Yes, that proves it’s not BLOCKED.

But it doesn’t show if it’s partially blocked, thus effecting it’s flow and operating performance.
 
So, today I started by the sequence: Throttle closed, chocke, ignition, 3 kicks, bike fires up. Runs in higher Idle without dying.
after 2 Minutes I was able to close the chocke and my pretty beast run in a smooth idle.
Tomorrow I will check the ignition point by a strobo light and check again the cold start. I assume the bypass for cold start was blocked.
I'm a bit happy everybody can assume... :D
 
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