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Bike shuts off if I use signals or lights...

Charging System, Wiring, Lighting
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kloan Member
Posts: 15
Joined: Mon Jul 02, 2007 9:08 pm

Bike shuts off if I use signals or lights...

Post by kloan » Sat Jul 21, 2007 3:28 am

I just got my bike running tonight... took quite a few attempts starting, but it finally ran and fairly well at that, for having not been driven in 3 years.

Anyhoo, I noticed there's no kill switch.. but the signal switch decided to act as one when I tested out the signals.

Any ideas what's up with that? Seems like the bike isn't putting out enough charge.. would that be the rectifier?

piecutter Member
Posts: 326
Joined: Wed Aug 18, 2004 2:03 pm
Location: Maryland

Post by piecutter » Sat Jul 21, 2007 12:36 pm

These bikes didn't put out alot of juice to begin with. Check to see if your light switch is shorting to ground. Sometimes the wires get pinched. It's a very simple wiring harness, so if you have a good multimeter you can make short work of finding the culprit. The rectifier is easily checked as well. Is your battery fully charged?

kloan Member
Posts: 15
Joined: Mon Jul 02, 2007 9:08 pm

Post by kloan » Sat Jul 21, 2007 2:42 pm

I have a multimeter.. but no idea how to test any of the connections.. :)

The battery was actually a little low.. it took quite a few cranks before the bike would start (since it hasn't been run in a few years), and I actually had to use a booster to get it going after than... so maybe the battery is still too low?

kustommusic Member
Posts: 585
Joined: Sat Sep 11, 2004 6:44 pm
Location: Goshen Indiana

Post by kustommusic » Sat Jul 21, 2007 6:31 pm

Kloan, Definatly Charge your battery, If you don't have a short it's the battery being low. Good luck, Kustommusic

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Re: Post subject: Bike shuts off if I use signals or lights.

Post by e3steve » Sun Jul 29, 2007 4:14 pm

When the lighting switch is used, additional windings from the alternator (ok, dynamo) are switched into circuit to provide extra current to the lighting cct. Only one phase (coil set) feeds the rectifier to charge the battery with DC; the other two phases provide the extra lighting support, so I suspect you may have two issues here:
1. The black wire connection at the coupler block (beneath the tank?) feeds the horn, ign coil, winkers and stoplamp switch, so check that there is no corrosion / resistance / looseness at this connection
2. The primary phase (ie: charging via the rectifier) could have a 'dry' solder joint owing to motor vibration - I've had this myself, although switching the key to the lighting position on my old CB77 caused it to continue to run (see 1) - take off the alternator cover and visually check all the solder joints; be brutal, give the solid copper conductors a good wiggle to see if there's any movement at the soldering (or the wire might even be broken)

Keep in touch.

Steve Edwards

kloan Member
Posts: 15
Joined: Mon Jul 02, 2007 9:08 pm

Post by kloan » Sun Jul 29, 2007 9:30 pm

Thanks for the advice.. my mounting plate came apart on my tank yesterday, so I have to get it welded for real (used JB Weld.. apparantly it's not good with gas)... so once I've got that fixed, I can get back to figuring out what's causing the short..

Will post results...

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