Help Help required please FZR250

is the battery being charged when the engine is running ?

 

Don't know. The problems listed above do get progressively worse during a weekends sprinting.

 

I will check it as soon as the temp in my bike shed drops to a sensible level. We are in a heat wave in the UK and a flat roofed shed acts as an oven.

 

Voltage remains constant at about 12.7V with or without the engine running. Do they suffer with regulator/rectifier problems (hopefully yes as it is cheap to replace).

 

I would first start by checking all the plugs between the stator and regulator for melting and corrosion, then check the stator is good before buying a new regulator

 

I will check. Reg/Rec only about £12 (21.26 AUD)

 

Battery charging is OK, the reason that it seemed faulty was that the regulator earth was on a panel bolt and I removed the panel to get at the regulator and didn't notice that I was testing without an earth ... D'oh. I will now move on to the coils

 

Bike still has the problem 50% of the time. When it is being a pain the rightmost exhaust is cold so I will test the coil and the float chamber.

Many people have suggested "**** in the carb" the problem is that you have to have a good sense of balance and you cannot trust the sidestand, so at my advanced age I am not going to try it.

 

If there's still problems since the shop rebuilt it, I'd be going back and getting them to investigate.

Before doing that I would suggest checking the slide needles for wear

 

I think the problem is a heat (coils?) or a intermittent blockage. Most likely the coil/lead/cap as the plug was wet when I checked it. Would any make of dual coil work as I can get new ones rather than an old genuine one?

 

You need to match the coil resistance against the spec in the manual.

 

Chasing parts numbers
Coil is the same part as fitted to Yamaha TD850
Plug caps same as Yamaha Thundercat