KR-1S.co.uk Forum

Now then my kips valve chums,
I have an interesting problem. I'm assuming bad earth, or very bad battery.
As its flat.
As a pancake.
That's been used as a taxi drivers seat cover.
The bike starts, idles great,
Then it revs cleanly as I warm it up.
Now the temp gauge doesn't seem to work properly, it rises a very small amount. And if I Rev it up the gauge seems to drop.
Now as I reach about 7 thousand rpm, it seems to bog/ stutter, almost loss of spark, then the powervalve opens and the thing takes off like a nut job, but the Rev counter has done a massive jump around the seven thou mark then jump up to where they should be, around nine, to ten thou.
And when they drop, the same leap on the Rev counter happens but in reverse as the revs approach the 7 or 8 thou mark!! Weird!,
Any ideas?
Cheers
Martin.

I have the same problem with my temp gauge.I think it could be the rectifier,but have not had chance to put a multimeter accross the battery terminals to check the voltage.

Boggy

boggy, check the wire to the temp sensor, if it is loose you are getting the problem you describe.

as for the rev meter etc it can be the rectifier don't drive to long with that problem ore alse you will fry the cdi in the end martin.

I'd say for certain get a new battery on it before trying anything else (don't even start it again!). As I understand it the reg/rec balances the output (charge) voltage from what it senses the battery voltage is, so if battery is flat the reg/rec could put out huge voltage and upset everything inc the CDI (in other words fry it).

With a new good batt on start the bike up and get voltage readings across the battery then see if anything else is playing up. Engine needs a good connection/earth to the frame, as does the reg/rec and the battery.

bozbridge wrote:I'd say for certain get a new battery on it before trying anything else (don't even start it again!). As I understand it the reg/rec balances the output (charge) voltage from what it senses the battery voltage is, so if battery is flat the reg/rec could put out huge voltage and upset everything inc the CDI (in other words fry it).

I never ever had a decent battery in mine.
the reregulator has to deal with the current/voltages from the stator all the time, no matter what voltage is behind it (battery/system). it will never send out more than +/- 14.5V. if it does it's broken.
for your regulator, actualy a bad battery is better than a good one, because the more it can send to the bad battery, the less it needs to discipate as heat -> less stress on the rectifier.

the moment a rev-counter starts flippin' on a KR, you should measure the outputvoltage of the regulator as soon as possible and stop revvin' the bike. often it's a sign that the regulator is broken and let's too high voltages go to the system. and the more rev's the higher the voltage. and the CDI doesn't handle them well and can fry within seconds.

Cheers for the help guys,
I had to call an electrician in the end.
The problem was the battery!
The battery was so knackered, probably dead cells.
It wouldn't take any charge, the action of the powervalve opening was dropping the voltage below 3 volts and dulling the spark, flipping the revcounter, and not able to move the needle on the temp gauge.
Mental.

Martin.

Glad you got it sorted, seems KR's can be pretty sensitive about system voltage, I'd still say once you've got the new battery on just check the charging voltage through the rev range to be sure (if that's not been done already?).

Doug.

Voltage was checked with new battery on, the charging voltage across the battery was 14 volts
And as the revs increase I saw a small dip to 13.7 volts showing the regulator was doing its job!
I have spare parts for the whole electrical system,but it's good to know I don't have to replace everything again!,
The electrics on a bike can be a right minefield, especially an ageing two stroker!
Now for a bit of a marathon to finish it for a bike rally in June!!

Cheers Martin.

Sorted!I took the temp sensor off and found the spade connector on the end of it was very loose.Put a bit of solder on it reinstalled,fired up engine,let it warm up.Took it for a test ride,problem solved.
Boggy =D>