Plug chop and plug colour help please - happy ending

[Shipleystevep]

Moved the needle to 3rd clip, wouldn't run on 3 1/2 or 4. Also replaced float valve with 300.

1/4 throttle


1/2 throttle


3/4


Full


I think it's better but still too lean for comfort, I don't have any more spares at home. I still need to check timing as Adam suggests, but what's your thoughts please. I want to get it safe enough to ride to Dan for setting up properly on his dyno. Would a richer needle and bigger main do the job?

[eden]

tweak your air screw and or bigger pilot

[Chris in Margate]

Definitely worth trying a richer needle if you can get one. It's quite a science changing needles and plug chopping. If you can, work backwards from WOT to tick over on the plug chops. Try and use 4 different plugs and a glove (to unscrew). Another thought: oil....not too much oil in there is there ?, that will weaken mixture.

And as I always advise.... is your TDC mark spot on. Things change when internals are changed. I don't IMHO believe this to be timing related but you say you are going to recheck so best to ensure your reference point is spot on.

Have you considered slipping a filter on to see the difference?

[Shipleystevep]

Thanks fellas I do appreciate this help.

Will look for a needle and or bigger pilot.
Already running a filter and using 3% SIP 2 stroke

Cheers steve

[Adam_Winstone]

That weak/hot on that jetting and timing I would be considering whether or not there is an air leak.

[Shipleystevep]

Starting to think that may be it, but I've re-checked exhaust and inlet manifolds.
Checked timing and re-checked TDC, it was at 19 degrees so reset to 17 degrees. Ordered a x13 needle to see if that makes a difference. Wanted to get it safe enough to get to scooterotica dyno, but worrying now there may be an air leak somewhere.

[Adam_Winstone]

Well, you're going the right way about testing, adjusting and testing again, rather than ignoring it an holing a piston. This is a pain but is the only way to identify and eliminate the cause.

Best of luck with it all.

Adam

PS - Leave the timing at 17 regardless

[Chris in Margate]

Adam I'm glad we met in the middle !

Steve there are a lot of threads on both major forums regarding air leak test. Cheapest way is Coaster's mountain bike inner tube. Cut in half opposite valve. One end over downpipe and the other end over inlet manifold. Secure with jubilee clips. Pressurise with pump and wash potential leak areas with soapy water and look for leaks.
Peace of mind.

Best of luck. We don't ALL agree but I promise you we are ALL pulling as one !

Good Luck

Chris

[Adam_Winstone]

^... 15 was the dealer's suggestion with 17 being my take on requirement. I am happy that we both managed to put across our thoughts though as that is what forums 'should' be all about

Respectfully,

Adam

[Shipleystevep]

Right ive learned some lessons today......
Finally managed to get it safe enough to take to scooterotica. What a top bloke Dan is.
I was sold a carb with a 40 slide but never checked this. BIG learn for me, Dan spotted it was a 60!! No wonder i was struggling to get close. Anyway Dan's sorted it. 35 slide 52 pilot 122 main 266 with x7 on 3rd clip. Removed air filter.
Results below, its lovely to ride im well pleased.

So thanks for your advice, if it hadn't been problematic i would not have addressed the potential issue with the timing.
Great help as always on the forum.