Hi all, As per the title, I recently fitted a new exhaust (technigas silent something or other) and a cone filter along with an iridium spark plug and "performance" coil and lead. In an effort to do it properly, I re=jetted the carb from the 79 which was in there already, to a 90 main jet. Not touched the idle. I've bolted everything back up but now it won't start. I'm a complete novice with these engines (Baotian BT49Q-11, 50CC) but my first though is its not getting any fuel, but when I take the hose from the filter, fuel comes out so I assume its getting through to the carb.
when you take the float bowl off to do a rejet all the fuel from the float bowl leaks out, and it takes quite a while for the fuel to refill it. if you are certain that the fuel has reached the float bowl, but it still wont start... then the next check would be that you are getting a spark at the plug.... you say you changed the plug and the coil, theres 2 possibilities that a wire is not put back properly. also did you check the gap on the new plug ? its not unheard of for a new plug to come with too big or too small a gap.
Thank you. I double checked all the electrical bits, I'm fairly sure they're ok. I didn't realise it would be hard for the bowl to fill after changing the jet and some of the lines so am going to try filling it directly with a funnel. Didn't check plug gap but crossing fingers it will start once carb is filled
Have you checked that there is a physical spark at the plug when you try to start the engine ? Take the Spark plug out.. plug it back into the HT boot, rest the plug against something metal on the bike, can be the frame or ideally the cylinder head, switch the ignition on and turn the engine over as if you are trying to start it. You should see a spark in the centre of the plug. If theres a spark.. bingo thats great, you have eliminated that from your enquiries... if there is no spark theres your issue.
Sorted! Thank you everyone. Once got fuel into the bowl it started right up. Sounds obnoxiously loud now however and still hesitates at 30mph which is annoying but at least it moves!
