hi all, 2001 pull start quad working ok 2 days ago, simply will not fire or fart, have good spark, fuel, compression does seems a bit low, in neutral and kill switch in correct position, tried in reserve and normal, petcock seems ok. no hard action on day was working ok so do not think chain has slipped, anyone have any ideas on a potential stupid issue ? cheers

 

Change the plug, then clean the carb out, no new parts, just remove the two jets, blow them and the holes they came from out with compressed air, check the jets are clear by holding to the light before re-fitting. If it doesn't start after that, check valve clearances, about 0.003" clearance on both valves, at TDC on the compression stroke is about right. If compression is very low, it may be time for a re-bore, but bikes usually get progressively more difficult to start with bore wear, unless you have seized it and scored the bore and/or trapped rings.

 

Cheers MM will let you know how I get on