piston/low compression saga concluded
Posted: Mon Jul 02, 2018 9:20 am
hi all, well after disagreeing with the mechanic to no avail ,I removed bike from his garage and messaged steve in boston who said "bring it over and i'll have a look",so I did.
the piston fitted is a 1959 650 with the skirt cut away in good condition with good rings and the bore standard, as the top end and barrel were disassembled not obvious what was causing the low compression , anyway steve said I've got nothing on leave it with me " .
the engine was rebuilt with new gaskets and he thought one of the rockers was fitted wrong as he could not get correct adjustment on one of the tappets,anyway he rebuilt it back up and I went back over to fire it up again.
loads of compression !!
but would not start, find that the new coil fitted was giving a lousy spark, new coil fitted and started no problem with a great sound through the megaphone
and after 15mins oil coming through to the top end lovely clear exhaust and good tickover.
I had a thought about the occasional backfire when kicking over that you said you get sometime could it be the wasted spark boyer ignition firing any fuel in cylinder if bike does not start after to a few kicks ??
the bike has been out on two decent runs lately and runs good and starts hot or summer cold without choke, tickover hot and cold is good.
the clutch release through the cable is not very good although there is no slip, a job for the winter.
took the bike up to crich yesterday nice turnout of ajs/matchless,were you all hiding from the sun somewhere.
thanks steve and your poacher mates.
the piston fitted is a 1959 650 with the skirt cut away in good condition with good rings and the bore standard, as the top end and barrel were disassembled not obvious what was causing the low compression , anyway steve said I've got nothing on leave it with me " .
the engine was rebuilt with new gaskets and he thought one of the rockers was fitted wrong as he could not get correct adjustment on one of the tappets,anyway he rebuilt it back up and I went back over to fire it up again.
loads of compression !!
but would not start, find that the new coil fitted was giving a lousy spark, new coil fitted and started no problem with a great sound through the megaphone
and after 15mins oil coming through to the top end lovely clear exhaust and good tickover.
I had a thought about the occasional backfire when kicking over that you said you get sometime could it be the wasted spark boyer ignition firing any fuel in cylinder if bike does not start after to a few kicks ??
the bike has been out on two decent runs lately and runs good and starts hot or summer cold without choke, tickover hot and cold is good.
the clutch release through the cable is not very good although there is no slip, a job for the winter.
took the bike up to crich yesterday nice turnout of ajs/matchless,were you all hiding from the sun somewhere.
thanks steve and your poacher mates.
