Need some info on The HUGH'S CDI

member3480

member3480

RICH
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Got some good info and all the directions on the unit but I have never had one to play with and I am helping a member out who installed it and blew the Capacitor that lets you run without battery. Got voltage from REG/REC and blew no fuses on one of my harnesses. May have hooked it up wrong because CAP has 4 connections and two are positive and two negative. Battery direction are very clear but battery less not. Any help would be welcome and I am going to reach out to HUGH also. Also does anyone know if the Sprax can replace that Cap? Anyone else use one of these and did it without battery. This bike starts and runs fine we just got to get the Lights and brake switch to work from fuse block.
Thanks
 
DADDYGCYCLES said:
CAP has 4 connections and two are positive and two negative.
Click to expand...
Chances are they're two independent capacitors in the same unit. They used to make tube radio power supply caps like that. Easy to check out with a meter, then follow the formula for parallel and series capacitors.
 
Thanks for getting back. I know a Sprax which I have used on other bikes works so I am going to take a shot at it and let him use one of those. I have used one on a CB450 auto that had a CDI setup and just had to use the small battery start to charge it first fire up. This guy has no experience with electronics or wiring but did it very well and bike runs fine so I think it was just a wire on the wrong terminal that fried it. No harm on any parts but the Cap. The Sprax can be negative or positive ground and in this case negative . I was just hoping someone else is running one so I can hear if there where any other issues.
 
Still need some help on this setup. Any info would help. Sounds like everything is hooked up correct and bike starts and runs fine. He got another CAP and within mins it blew. Anyone running this setup and how did you hook up yours SPRAX - CAP that comes with Kit - Battery???? We need more info on new products that are out there. This is a very easy install but running battery less seems to be a problem.
 
DADDYGCYCLES said:
Still need some help on this setup. Any info would help. Sounds like everything is hooked up correct and bike starts and runs fine. He got another CAP and within mins it blew...
Click to expand...

Rich, any electrolytic cap rated above +16v should survive and not blow, unless,

- There's some wild/aggressive voltage/current fluctuations,
- Momentary dead shorts to ground.

A battery will naturally absorb those kinds of spurious voltages, stabilize them, and you may never detect them. A large electrolytic, exposed to rapid charge/discharges, will get hot and blow.

You could test using a battery. Start with a small, perhaps 1 amp fuse. See if it blows. Go to a larger fuse, repeat. Looking for rapid, intermittant grounding...
 
Two Many you are right on the head with the test but the guy I am helping doesn't know how to do much testing and from the start I told him throw the Cap away and use a battery. Again not knocking any product and just sold a couple harnesses to guys using power dynamic setup and wires up basic the same again using battery no problem. I think because he hooked it up wrong the first time that maybe he also took out the reg/rec . Bike starts and runs fine just can't get the voltage from the reg/rec to the fuse block so all the other stuff will work. He is going to try a battery and I told him the same thing put a fuse in and see if it pops. I would just like to have a little more info for my knowledge for the future on the different ways people hooked this CDI up. Nothing new CDI have been around a long time and have used many on Honda bikes. I also told him to contact vendor he bought it from and see if they had any issues . I get this all the time and tell everyone. You want to ride a older bike (25 yrs plus ) buy some books and tools you will need them. If not pay someone like me big bucks or just go buy a new bike. Any other info I would really appreciate or I am just going to have to buy one and break it down lol. This guy lives nowhere near me so text and email and photo's is all I got to work with.
 
I suppose you could put an Ohmite power resistor, of about 2-5 ohms, in-line (in series) with the cap. That would curtail rapid current surges in the cap, reducing its temps, yet still provide a stable voltage reference for the regulator.

OhmiteResistor.jpg
 

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