Looks to be the regulator not regulating.
There are lots of info regarding charging and reg/rec. Search in the tech section. A little light reading before bedtime, all will be revealed. May take a few nights but you will be the wiser for it.View attachment 135790 View attachment 135791 View attachment 135792 View attachment 135793 View attachment 135794 View attachment 135795 Ok new battery fittied and the bike started on the starter motor, crancked over lovely.... multi meter attached I rev the engine and the meter read 13 volt and as i throttle the bike it keeps rising up to about 21 volts
it has to be the reg/rec.
I have checked the wires and both connetctors at the multi blocks the 3 pin left side which has two wires from the reg/rec but three from the loom show a slight signs of heat on the outer casing of the multi block .
I am so confused bloody electrics mess with my head dam my ignorance
All the best funky
I have had a little read and have got little knowlrdge about these now there is no wrong wires they are plug and play my confusion is in testing the Reg/Rec thats so confusing ....This is what i have worked out so far.... diodes pass current one way and not the other so as far as i am aware is that the stator give current at A/C into the Reg/Rec then it converts the current to D/C it limits the voltage to 14.5V as to not over charger the battery and electrical system ... so if the battery is over charging to the point it swells in the battery try it has to be the Reg/Rec there is no other reason as the Regulator part of the Reg/Rec is clearly not doing that as SUperjet stated afew posts ago , I have ordered a new Reg/Rec from Germany so will see if this does the trick ..... Thanks for all the responses will let you know how i get on .
All the best Funky
Gary, I have a few questions about 750's. I talked to Hugh at Hugh's Handbuilt's, and said a stock cam would be plenty. I'm curious, on your XS650 big bore, what modifications other than the CC increase have you made, and what recommendations would you make to get the most bang for the buck BTW, it's an '81.I crank a high compression 750 with a standard size 14L-A2 lead acid no problem, IF the timing is not too far advanced. While rare on the XS a failed oil seal can fill a starter motor with motor oil. Starter has a slow (honestly WET) sound if this happens.
That's what I want low RPM torque. I've had high RPM stuff in the past (Kawasaki 750 triple) and an early Mazda RX-7, and it's not fun trying to keep something within that narrow of a power band. I'm going to have to do some research on cams, as I want something that will make good power down low. BTW, what carbs are on madness? What's your opinion on flat slides?The 750 in Madness has a lot of internal "upgrades" but it was built decades ago, long before I bought it. I have a completed big bore motor with no other mods but it's still sitting on a stand not in a bike. Sorry to be of no help.
One thing I will say is to be cautious of how much you mod. A motor that has been breathed on for big HP numbers often ends up being little fun in normal street use with the horse power found only at high RPM where it just isn't used that often. I kind of tuned modded to trade off the High RPM bias on madness for more grunt lower and enjoy it more now. Smaller carbs, more restrictive exhaust, the biggest changes maybe retarded the timing a bit.
I'm probably going to go small on the exhaust. When you say pumpers, are we talking flatslides? If so, who is a good source?She had VM38's when I got 'r now VM34's nothing fancy but they work fine. I REALLY need to grab that set of pumpers the Grizzly bear sent me and install 'em
I agree with Hugh, nothing wrong with a stock cam 'specally a later one. Exhaust header length and a muffler can that can generate a clean back pulse help with low RPM grunt. If you go with large diameter headers for the look, inserts are needed.
Those carbs are Mikuni TM36/68 4-stroke flat slide pumpers, Gary. They're from the Radial Smoothbore design group. In their (questionable) wisdom, Mikuni gave them the TM designation instead of RS because as sold they're set up for single carb use, and RS carbs are configured only in banks of 4.