UK Monster Owners Club Forum - View Single Post - Monster 600 faulty CDI's

Nickj · 20-08-2018, 08:00 AM

The units are pretty standard Japanese sourced parts by Kokusan Denki, they should be BB1105 units.
Choices are replace with the same, either new or used, there are always some on ebay.
You need to be careful not to get the BB1105A boxes that have different advance step points for high comp pistons.
These are also used on quite a few old jap bikes.
They are very old and clunky though.

Procom make a new replacement PE-C-MD900-A that is a lot cheaper new and uses slightly more modern electronics which may be your best bet. Bigger fatter spark and smoother advance stepping. Ebay has quite a few at around £100 from the US.

I think that there is a fully tune-able replacement but I can't remember who makes them, some of the racers will know who makes these.

A thought... IF it's on full advance at start up then tries to advance more then it would seem to be running. Is the basic set up of the pickups right and not set up to be slightly advanced??

20-08-2018, 08:00 AM	#3
Nickj Too much time on my hands member Join Date: Jun 2007 Location: Forest Of Dean Bike: S2r Posts: 3,196	The units are pretty standard Japanese sourced parts by Kokusan Denki, they should be BB1105 units. Choices are replace with the same, either new or used, there are always some on ebay. You need to be careful not to get the BB1105A boxes that have different advance step points for high comp pistons. These are also used on quite a few old jap bikes. They are very old and clunky though. Procom make a new replacement PE-C-MD900-A that is a lot cheaper new and uses slightly more modern electronics which may be your best bet. Bigger fatter spark and smoother advance stepping. Ebay has quite a few at around £100 from the US. I think that there is a fully tune-able replacement but I can't remember who makes them, some of the racers will know who makes these. A thought... IF it's on full advance at start up then tries to advance more then it would seem to be running. Is the basic set up of the pickups right and not set up to be slightly advanced?? __________________ "The final measure of any rider's skill is the inverse ratio of his preferred Traveling Speed to the number of bad scars on his body." Song of the sausage creature Last edited by Nickj; 20-08-2018 at 08:02 AM..