Topic: Cold Weather Issues

[CB650 Wolf]

Does anyone else with a 81 CB650 have issues with starting and maintaining an idle during cool to cold weather. It just dropped down to the low 60's in the mornings here and now if I can get my bike started it wont stay going for long.

[w1sa]

If the bike sits for a lengthy period, you could have trouble starting/initial idle.

The auto fuel cock unit works off vacuum. Enough fuel will not flow to the carbs and intake till bike is cranked/run long enough for the unit to top up the bowls. Hence initial start up/idle may be difficult.

The hard start condition might be compounded by a weak battery charge.

[Buber]

It is well known "habit" of CB650. I cured it quite far by:
1. Iridium spark plugs - probably the best mod
2. Routing the power supply to ignition coils directly from the battery via relay - this way I have always max voltage on the coils.
3. If you have CV crabs, they will have acceleration pump (not sure about mechanical), then BEFORE cranking, do few (4-5) quick twists of the gas handle - this will squirt extra fuel closer to the cylinder and greatly help with start.

Hope this helps.

[BVCB650]

Put a "milkbarn" heater next to the heads on a timer. Then you have a block heater. 10 minutes of that and it will start up. BTW, it is 28 here this morning.