When running the bike and stationary I noticed that there was methanol dropping quite fast from where the exhaust slips on to the spigot at the head (modified for ease of maintenance). I’d put 2 gallons in the tank and did a maximum 14 miles and there seems to be under a gallon left so huge fuel consumption even for a 350.
First job was to pull the carb away from the inlet, keep at same angle and turn the fuel on see if leaking. Result dry even if I tilted it and shook it.
I’d read that the choke sealing could be a problem and stripping the carb and testing with WD it was leaking so I swapped it for one from another carb leaving the mechanism off so that the spring could seal at the base unimpeded. Squirting WD through none was getting past the seal. Started bike and the 8 stroking was only just off of closed throttle and cleared with just a little more throttle- much better than before. Experimented with pilot screw and there was marginal difference. However, methanol was still dripping out of the exhaust joint quite fast.
There is no popping symptomatic of an air leak in the exhaust. I can seal the head joint but then the excess methanol will get into the silencer and kill the fibre material.
I swapped all the ‘upgrade’ methanol bits from the 32mm carb to a 30mm Mk2 and ran the bike. The 8 stroking was slightly worse but the methanol dripping from the exhaust was a little less but still not good.
Somehow this seems to be two problems. The choke plunger sealing made a big difference and it was possible to warm the bike up at low ish revs. However the dripping fuel is a problem, and odd that it still drips with the smaller carb but not so much.
Looking in the oil tank the oil (caster) has diluted, methanol washing down the bore as well as out of the exhaust joint.
Any suggestion please - Hill climb only a few days away.
