Ktm sx 125 with 200 Topend jetting help!

Hello there people

I've gone through the rigmarole of converting my sx125 2003 into a 200 I've had a few hiccups along the way which I have overcome but now I'm stuck on the jetting situation.

Little info on the bike

It's a 2003 sx125 it's had the bottom end serviced with new koyo bearings and seals with a 200 conrod fitted.

To convert to a 200 I've used a exc barrel,xcw head and a vertex piston Using the keihin 39mm carb, doma pipe, pro circuit shorty silencer and vforce reeds.

My situation is this - I've got the bike ticking over also bottom end is fine it's just the mid it's spluttering but once I get past this the bike pulls hard through the powerband my carb is running a 178 main-42pilot-stock slide and stock needle on second from top 1 1/2 turns out on air screw.

Like I say bike ticks over all day it's just the mid there isn't much pull just hesitation and splutter-plug is a light brown colour.



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