SOHC.co.uk Forums > CB500/550

cb500 non stsrter

(1/2) > >>

blade918:
hi all hope someone out there can help i bought 1973 k2 cb500 four usa model very rough spent 1 yr cleaning stripping repainting etc came to start engine fired on all 4 cylinders then nasty noises turned out 3 gears broke engine out again srip new gears rebuild back in frame pressed starter fired only on 1 and 4  swapped blue and yellow wires to coil 23 run ok not 1 and 4  found fault on ht leads so bought new coils and condensers points ok new plugs  checked for spark without plug caps sparks on all cylinders, plug caps back on will not start battery low at this point so charged it up ,fully charged switched on no lights on panel bike dead ? checked fuse blown new fuse
all lights back on pressed starter fuse blown put new fuse in now turns over but will not run  stood looking with ignition still on saw blue wire to coil smoking turned off swapped blue and yellow wires yellow one smoking thinking must be a short on blue fron points to coil by passed this wit a wire made up turne ignition on this smokes as well so no short on blue wire in main loom i am lost at this point anybody out there any answers many thanks blade918

McCabe-Thiele (Ted):
Not trying to insult your knowledge - are you sure the points are connected correctly in terms of insulation where the condenser & coil feed wires fit between the points spring etc?

Not sure about this idea but do you have a good earth connection between the engine & the frame fuse blowing indicates a dead short somewhere or a poor earth using the next best method of completing the circuit..

Bryanj:
Agree, bad earth, possibly bad coil or wrong connection at coil

blade918:
thanks for replys points are good wiring not touched it did fire up and run ok but had to strip down re broken gears wiring is back exactly as was new condensers new coils earth at coils paint scraped back so should be ok  there defo a short somewhere ive put a 20 amp fuse in temporary and the red wire from battery to fuse gets hot i admit electrics is a dark art to me so help needed thanks

McCabe-Thiele (Ted):
Putting a bigger fuse in is a bad move tbh.
You risk some wire melting elsewhere or a fire in the worst case

Just a thought, I would avoid using the electric starter due to the current stress in a potential earthing issue. When you check the static timing with a bulb does it all check out.
Are you getting a spark at the plugs?

Navigation

[0] Message Index

[#] Next page