Boldorclub.nl

Hi,
I have a CB750FB 1981 with standard VB52A C carbs.
I have removed the carbs, stripped and thouroughly cleaned.
Carbs have been synchronised and she runs beautifully, from tickover and right through the rev range.

The problem I have is cold starting the bike. I am currently opening the choke fully and attempting to start with no throttle opening. This seams to be the only way the bike will fire/start, but it does take a number of starts (and battery power), sometimes taking up to a minute before she starts to fire and eventually will start to run. It takes some throttle opening and revving, before she eventually settles down and will run on the choke until warm and the choke can be taken off.

My older CB550K3 with an older less complicated PD46A C carb, used to fire up immediately you pressed the starter and would run immediately on choke without any hesitation or problems.

What is the best technique for starting a CB750F from Cold?

Is there anything additional I need to do to the carbs to get the bike to start easily and reliably from cold?

Your help support and advice is very much appreciated.

Andy.

Hi Andy,

The best and cheapest option is to drain the carbs before the start. Another option is replacement of the old OKI units by something more modern. Sixcenter sells Marctronic units (plug and play replacement) and they work fine, but have their price. It also seems that Ignitech does a good job but I don't have any experience with it. A unit is on it's way to me.

Cheers, Andre