Winter starting ! GPz750

Hi,

maybe some of you have the same kind of issue, even with a different bike. Temperature has dropped recently and goes around 0 Celsius at night. Bike is stored in a partly open garage. It will not start in the morning up until when it gets warm like around 10am. If it sleeps inside the house, then no issue, starts first thing. Any idea what may cause that ? here's a list of things I've checked :

Recently rebuilt the starter engine, top end (changed all gaskets), timing perfect, battery good, brand new synthetic 10w40 Repsol Motorcycle oil.

My guess is the carbs but it doesn't run rough. I haven't cleant them as I do not have yet the carb synch tool for after the clean-up.

thoughts ?

Max

I doubt that it's the carbs; especially if after spending the night indoors you can take the bike outside (where the carbs are sucking in cold air) and the engine will start. It may be a combination of the battery being cold (even though it is new) and the motor oil being a bit more viscous when it is cold. It could be that because the oil is slightly thicker it takes a little more current to spin the starter and with the battery being cold it doesn't have quite enough reserve to spin the starter at a fast enough rate while still providing sufficient current to the coils. You could try using a battery tender to keep the battery at the top of its charge and/or putting a heating pad on the engine overnight to keep the oil from getting too cold. Ed

+1 on Ed's comment. Cold is letal to battery, always use a battery tender.

I have a similar issue, but it turn out the choke plate axle is divided in two parts. When you apply the choke lever, the 2 axles must return by the force of a torsion spring. It results one of the two torsion springs is very weak and old... so cylinder 1 and 2 choke plates did engage, but neither 3 and 4 did.

This is in Keinhin CV34 carbs... I think GPZ has Mikunis BS34.

yeah, mine are mikunis. I figured there wasn't much i could do about it - gonna be sleeping inside for the next 2 months ! thanks for your replies guys.

Have you consider an oil pan heater?