NEWBY: Braaap Mercury + Molkt 26mm

HI guys,

Long time reader, first time poster.

Have a 2014 Braap (Sol Invictus) Mercury (ST-250) single cyl 250cc.

I had an accident (was merged on) by a 4wd who tore the stock exhaust off (and I managed to keep upright) so cut the pipe back, and put a cheap ebay stubby pipe on.

Has been backfiring and gurgling for ages, till I read that a Molt carb, along with the EGR removal fixed this in other models.

So, ordered a 26mm Molkt, air pod and the blanking plates etc needed for the EGR removal.

Did the mod on the weekend, and all seems OK. Was originally having float issues (was cutting out at 1/5th throttle onwards) but bend the tab just a smidge and it seems happy now, although Im getting ALOT of carbon on the plug (ceramic color looks fine) so its clearly running rich.

Now the weird thing - the idle mixture screw does absolutely nothing. Bedded in, to all the way out - changes nothing. Not the idle speed, or the sound... nothing.

So hoping someone hear can confirm for me - 1. the molkt idle screw adjusts the air, not the fuel which means 2. I need a smaller primary jet.

Can anyone confirm/suggest anything?

Any advice appreciated!

Cheers!

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