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Issues with installation of electronic ignition CA77

Points Based Ignition | Electronic Ignition Upgrade
e3steve
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Re: Issues with installation of electronic ignition CA77

Post by e3steve » Sat Dec 12, 2009 6:06 pm

Greggie-e wrote:Hi all,
I have one of these new electronic ignition kits for the CA77 and have a few questions for anyone who has installed one before.

The instructions say that the red wire should be connected to the primary switched power source on the coil and the yellow wire should go to the coil connection that is not switched.
My problem is that my coil seems to be switched on both sides. Both sides read 0 volts with the bike off and 12 volts with the bike switched on.

a) Is my electrical system incorrect?


b) Will having 12 volts connected to the yellow wire blow up my electronic ignition?

c) Is the primary connection the one with the "+" symbol (I think it is) or the "-" symbol?


Also slightly related is that the screws for my points cover and the points themselves have had their heads butchered. When I went to the metric nut and bolt shop they said the threads are not metric. Are they a special thread?


Cheers,
Greg
When the points are open the '-' terminal on the coil will read 12V as a result of hysteresis where the voltage is passing via the coil's primary winding and will read so on a voltmeter. There will be little current available at that terminal though.

Ab) Most probably but not necessarily

Ac) They're both primary, really; but for these purposes '+'. The bike is negative earth, so the coil references to ground via the points and points plate; that's the '-' connection.

Greggie-e
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Post by Greggie-e » Sun Dec 13, 2009 8:17 pm

I took the bike for it's first ride yesterday with the new ignition.

The bike pulls a lot better and it revs a lot higher than it did before.

however it did completely die at one point, I think it may have had something to do with the spark plug leads interferring with the electronics as I have not secured all the wires away neatly yet.

Does anyone know if coiling the wires of the electronic ignition interfees with the electronics?
I shouldn't think it would, but I am not an expert when it comes to these majic boxes...

gramey7
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Post by gramey7 » Mon Dec 14, 2009 10:22 am

You can get the correct JIS thread screws from Joseph Tubbs at icemanjat@hotmail.com. He sometimes offers an assortment on eBay. It's good you used the old screws. If you order screws from Honda using the original part number, you will get screws with a "-0A" suffix which means they are the newer ISO thread metric, not the old JIS metric.

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flathead
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Post by flathead » Mon Dec 14, 2009 10:39 am

Some jis fastners available at McMaster Carr.
http://www.mcmaster.com/#jis-(japanese- ... ws/=4xgs22

I usually order thru the shop account here but also have ordered personally from them with a credit card.

gramey7
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Post by gramey7 » Mon Dec 14, 2009 10:49 am

The McMaster Carr fasteners are "modified JIS" threads which are the same as the present ISO threads. The Bill Silver Restoration Guide identifies the different thread pitches for the old and new styles, i.e, for 3mm dia. the old pitch was .6mm now is .5mm. 4mm dia was .75mm pitch, now .7 mm.

Greggie-e
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Post by Greggie-e » Thu Dec 17, 2009 8:15 pm

Ok so the electronic ignition is fitted and the bike runs.
And when it runs it runs really well...

However, occasionally it cuts out completely. I think this is due to the wiring coming close to other wires and disturbing the pulse.

I have re-arranged the wiring a few times, but I think I am going to have to shorten some of the wires as I have about a foot of extra wire.

I am taking it on a long ride this weekend (about 150km) to see what happens.

Cheers,
Greg

rustywrench
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e-ignition

Post by rustywrench » Thu Dec 17, 2009 10:44 pm

Greggie-e,
RE: your cutting out problem, I don't know where exactly you mounted the control module, but I have seen electronics be heat sensitive. I seem to remember it suggested to mount said module in a well ventilated area. Not sure of the CA, but on the Cl's the upper motor mount is suggested.
Just a thought, RW

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