turn signal lights only blink @ higher rpm

[llamakc]

Brock and I did a turn signal modification on his 79 XS11 Special. We found a pair of aftermarket ones at a boneyard and mounted them on the tail light brick.

After rewiring we discovered that the lights only show solid UNLESS the bike is revved higher. When revved, they blink.

1. Is our problem a miswiring issue?
2. Is our problem because we used solid copper wire from Lowes (14 I think)?

Thanks.

[ratbyk]

Signal Issues

Sounds to me more like a battery issue. The blinker module on XS's require lots of voltage to tick over. If the battery does not have a good 12.5 V then the they won't trip over properly. When you rev up the alternator will boost battery voltage and make the blinker function. The solid wires will not have any effect. Although over time if they are in position to flex they will "work harden" and break.
Ken/Sooke

[brock]

i didnt think it was a problem with the wiring either. I was more concerned that these new lights are drawing too much voltage. I might try to change out the bulbs in the new ones from the old ones, or look into LED lights.

But do you think it's an early indication that my battery is going bad? I'll put it on the charger tomorrow, but I'd like to get a head start on it if possible.

[ratbyk]

Flasher Unit

Bulbs drawing lots of voltage Is not likely a problem. The more voltage passing through the trip mechanism in the flasher will only make it flash a little faster. (up to a point)
First there must be enough voltage available to pass through the flasher and onto the bulbs/ground to trip the flasher.
XS flasher units like lots of voltage. Most of us who have had an XS for a few years have learned that when the signals quit at idle then the battery is low or getting near the end of it's life.
Early this summer Ratbyk signals stopped working at idle. The battery was 4 years old. I did not even bother testing it. (I was leaving for Montana and did not want trouble on the road) I just went and bought a new battery. Signal immediately started working at idle again. Just my experience Of over 55 years of owning motor vehicles.
Ken/Sooke

[Jerry]

Ratbyk pretty well sums it up. Turn lights not flashing at idle or low RPM ususally points to a battery going bad.

However, there are a few other things to check. First, make sure all your ground connections are good. If not, or if there is corrosion in other connectors, the extra reistance will require higher than normal voltage to operate the lights. You didn't mention if you are still running the original fuse block. If so, replace it! The block is a main source of electrical problems for all older Japanese bikes. Do a search on 'fuse block' for past threads on replacement units. Even though the fuse 'fingers' may look good, age and corrosion will cause them to go bad.

You may want to replace the battery cables. Again, corrosion under the wire wrapping and in the terminal-to-cable crimp will increase resistance, causing problems. Your bike may also start easier with new cables....mine did.

Finally, the flasher unit may be going bad. Not likely but possible. Get a 2-prong flasher from your local auto parts store and give it a try. With the bike connector held like an upside-down "U" the 2 prong unit will use the center and right-hand connector. If you plug it in wrong nothing bad will happen, just the lights won't flash at any RPM. You can also swap in an electronic flasher, which takes less voltage to work, but this only helps prolong battery replacement, it doesn't fix the root problem. Both alternatives loose the auto-cance feature of the OEM flasher. An OEM replacement unit is around $70.00 from Yamaha.

Most likely your battery is the culprit, but it doesn't hurt to check a few other things before you replace the battery.

[TopCatGr58]

Just a little P.S.,

If you do go to L.E.D.'s, then you WILL need the electronic flasher, cause the LED's don't draw enough current/load for the thermal flasher to heat up and trip, the electronic ones don't care, they flick easily, a bit more pricey at about $8.00 but will ensure your LED's will flash!
T.C.

[rover]

Had the same problem with my SF, even after a new battery. Checked the cost of a new flasher, but the cost was crazy. I got an automotive heavy duty 2 prong flasher, no more problem. The self cancelling (original) flasher has three prongs. One of them is for the self cancelling feature. I plugged in the two prong, and first it did not work. Then plugged it in the other way, and works just fine, but, of course, you lose the self cancelling feature, but I can live with that.

[Luxury]

The bottom line is that the stock mechanical flasher that works with auto-cancel wants to see lots of current. If you have non-stock signals with low current bulbs or LEDs or if you have corrosion in your stock signal sockets, the stock mechanical flasher will not flash (I have had both problems in the past). The low draw bulb problem is solved by using an electronic flasher as suggested above, and the stock signal fix is to disasembly the sockets and clean them up (it's kinda goofy the way the wires connect the bulb socket). I like the auto-cancel feature so it was worth some effort to clean up the bulb sockets.

[Dennyz]

I would also recommend soldering a ground wire to the bulb housing. Frame grounding on the XS can be problematic.

[hollywoodxs11sf]

Relay Is To Blame

I had a problem with signals not flashing at low RPM on my 79 Special. The problem ended up being the silver relay canister under the right side cover. Many refer to it as a flasher, but in reality is a thermal relay.

I pried the lips of the small can away from the base plate, and, after opening it carefully (can will remain tethered to base plate by a single wire), discovered that the contact points were dirty and sticking together instead of separating when the relay reached the correct temp to cut off power.

I cleaned them with emery paper, added a tiny spray of clock oil (doesn't gum up like WD-40), and the signals blink, rather quickly, even at a stop with the brake engaged.

Try cleaning the contacts in the relay and I can almost guarantee lights that blink at a stop.

[ratbyk]

Flashers

Thanks for the tip there hollywoodxs11sf. Next time my signals slow down I will try that. Definitely makes sense to clean up the contacts after 25+ years.
Ken/Sooke

[jeffe]

My 78E had the same problem. After I replaced the fuse block with the individual blade types it works great.