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snagger
08-May-2005, 15:47
Hi, posted this on UK Mon with no response...

'01 M600 when started cold, fires straight up, and seem's to rev hard when on choke, try to back the choke off, the engine then struggles to idle till warm, or rev's high with choke.

Before fully warm the bike has a low speed 'stumble' when pulling away, this is noticable, to a lesser degree when fully warm too.

The bike is totally standard.

Is there any way to fine tune the jetting to eliminate this?
I'm thinking maybe pilot screw's, how many turns out are they as st'd?
Are they a bit rich or lean as st'd?

Any help appreciated.
Regards Phil
Jon
08-May-2005, 17:43
Not sure if this will work with the monnie 600, but you couold try a smaller front sprocket. This smooths out the jerkyness on the 748/9** series
snagger
08-May-2005, 22:19
Hi, I've got a smaller sprocket fitted, which as you say help's.

The bike still suffers from a 'stumble' just off throttle tho.

Phil
Jon
08-May-2005, 22:39
If you can hang on a bit Nelly will be back soon. I'm sure he can help you
snagger
09-May-2005, 22:20
Ok, Thanx,

Phil
Ducman851
11-May-2005, 06:36
You could back the pilots out abit, stumble is usually indicative of a lean condition.

Also, how many miles/kms ?
snagger
11-May-2005, 19:31
Bike has only done 5500mls, everything is stock.

I was figuring it may be a tad lean by the temperemental cold running.

Do you know how many turns out the pilot screws are as standard?
Just so I have a base to work from (tried one screw, think it was about 3 turns to fully seated)

Thanx, Regards
Phil
psychlist
11-May-2005, 23:30
You need a stage 2 dynojet kit & hi-flow air filter ;)
The transformation to low speed pick-up is phenomenal :o
www.spareshack.co.uk
phil_h
11-May-2005, 23:32
Adjust the pilot screws to 6 turns out IMMEDIATELY !!!
You will def get a smoother running bike, cos the std settings are WAY too lean.
snagger
12-May-2005, 23:55
Ahem, is that SIX turn's out!!!!
Is there that much threading....

What about the midrange, is there a benefit from lifting the needle's too?

Six turns....

Thanx, Phil

Six turns (recurring)
Ducman851
13-May-2005, 06:49
I think 6 is abit much, but coming out with them is a step in the right direction.
Rob B
13-May-2005, 08:48
Oh, and make sure the carbs are balanced. very noticable at low throttle openings.
snagger
13-May-2005, 20:51
Thanx for your help all.
Just balanced the carbs last week (were ok).
I'll have a tinker with the pilot screw's, find a happy setting and rebalance carbs.

Thanx, regards Phil
rockhopper
13-May-2005, 21:45
Get the valve clearances checked. Our M600 did the same as yours but now it starts without choke (or perhaps just a tiny bit if very cold).
phil_h
13-May-2005, 23:19
Well, I've hunted around for the carb info I used to set mine up from, but cant find it.
I'm pretty sure its 6 turns, cos the pilot screw thread is very fine, but I'll try and check mine before I go on holiday on sunday and report back (they are a ****** to get at after all !)

(Nelly and/or Louigi will know off the top of their heads I should think)