Thread: 70 h electrical problem and speed question

My ct70h has an electrical problem the headlights are dim on hi or low beam .the brake light wont light with front or rear brake levers with the lights on ,the taillight dims way down and the brake light just slightly glowes the head light also dims.the headlight gets brighter as the rpms increase. when i restored the 70 every thing electrical seemed to work other than the head light its always been dim both hi and lo.was it that way new because of the generator ? i thought the headlight was all that ran off the generator other than charging the batt through the rectfier for tail brake and horn . i know grounds are important so i ran an extra ground from the switch ring nut to the battery neg and frame. i can ohm for groungs any where on the bike and get conutity. i suspect i have some wires crossed but dont know. i did mess up and shoot the lo beam and inst lights by unplugging the rect on the dc side.

Besides the electrical problem did the 70 h ever get over 35 too 40 mph? the parts on this bike are orgional.it seems to run fine

A good running CT70H should be able to reach upper 30's mph to low 40's with an "averaged sized" rider.

Have you checked the battery? The tail light/brake light run of battery power. The headlight/speedometer light runs off the stator and do brighten or dim based on rngine RPMs. Look the wiring over again real good. Check to make sure you have good grounds. If all else fails you my suspect a defect ignition switch.

My H has the identical simptoms as yours c-ville. Also add in the headlight doesn't come on sometimes. The tail light issue seems to be getting better on it's own the more I ride. HG is right about the switch. I've narrowed mine down to that. The contacts inside the switch aren't what they used to be. The tail light circuit is better and headlight needs help now. I need to dismantle it and clean up the contacts. New switches don't have the old style key and mine has an H punched through the middle. I wouldn't be easy letting go of that.
40mph down hill full throttle and 30 at the top with a fresh carb rebuild. No baffle in the exhaust and 65 jet is running a bit too rich. After market filter might fix that issue. The 30mph is keeping me from changing the stock gearing.

Regarding speed, my H will do 35 on flat with fresh bore and piston and all stock.
I have found I can get a little more speed by advancing the timing (opening the points) but you end up loosing low end.
I'm 212lb. It would probably do better with a lighter load.

Speeds are normal and you should charge or replace the battery.

thanks for the info i will try your ideas and check real good again. the battery cells were slightly low on distilled water two of the three and the switch when,I started restoration came apart on the inside of the bike frame, springs ,contacts went everywhere I had to make some of the brass pins that the key contacts to turn the switch on, I sure could have bought one cheaper but it wouldnt have been orgionial.
at least I know now the speeds and electrical issues are as near normal for the time 1970 when the bike was built and its not some kind of weired self induced problem.
Now I got to put some pics on here if i can figure out how.
Tkanks again.

Tonight I took the battery off and charged it for about half hour put it back on and i got tail and brake lights, good n brite. but i don't think the batterys holdin charge.checked the volts at the green wire from the generator best i can remember it was about 10 to 11 at idle and a high 5 out of the rect. should'nt that keep the battery charged? would a low or weak battery dim the headlight?

Oh shiioot sorry. Sould have said some more on the switch. Getting the contacts, springs and balls back where they go isn't bad but sqeezing it back together and barbs flattened back down can be tough. At least for a Z it's that way.

If you're having problems with the keyswitch, IMO you'll end up happier replacing it. I've taken them apart, cleaned the contacts and sealed everything back up "successfully". It's not like trying to solve Rubik's Cube, but not the easiest repair by a longshot. These were never intended to be serviceable, so you're on your own...no repair manual, no exploded drawing or broad knowldege base to share. With a little basic electrical & mechanical talent, it can be done though. That said, even when properly sealed with dialectric grease, once these switches are f...ummm...messed-up, they rarely seem to be quite right. For most of the past decade, I've had to twist the key repeatedly, from time-to-time, to get the lights up to full brightness. It lasts for a while, but it's never long before the contacts develop resistance and the process must be repeated. Better results have been realized with other bikes, just my luck, eh? Kinda silly, when you consider the cost of a new OEM switch, at least while they are still available new.

My 1970 HKO will do 43 MPH all day long with my 225lbs on it.
Slight backwind will hit 45MPH. Now going down hills, I can get it over 50MPH!
That engine sounds kindaof neat at that RPM's. Kindaof like a sewing machine on
steroids...