[Herdy]

Hi all
I have also just bought a 19 a week ago and a similar issue ...have done about 100 miles running it in and started to wind it up ready to race at the weekend ..i too noticed a very loud bang/knock from the cylinder when shutting off and rolling down big hills and dose not run very smooth when pottering on the road around 1/8 throttle .. ..l have dropped the pilot jet down to 40 which has made a bit of improvement and the spooge out of the exhaust has about gone ..but still have oiled two plugs..both while warming up the bike ...if my thinking is right it is still rich on the pilot as the engine starts instantly with out choke?

i am just going to check float height and try a 38 pilot jet as my next step ( my old 2012 racing i used to run 178 main 35 pilot and a EE needle ..but still was never good around 1/4 throttle )

at the moment I'm running Motul 800.. 90cc to 5 litres (55:1) 175 Main 40 pilot and the EF needle middle clip sea level about 12 to 14 degrees c. Isle of Man UK

any help would greatly appreciated ...apart from this jetting issue the bike is fantastic and definitely confidence building compared to the 12 :O)