Turn signal help

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Jan 1, 2024
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When my bike was still living life as a Hi-Rider, to add to the "chopper" look, the PO had apparently removed the turn signals. I have now purchased both a front and rear set of Lucas turn signals. The PO had clipped the leads at both the front and rear. Have installed my replacements and connected them to the leads as per the wiring diagram in the workshop manual. When initially installed as per wiring, the right rear and left front would light but not flash, when switched at the handlebar control for right hand turn. The other signals would not light, when switched to the left turn position. Upon swapping the right front turn indicator lead to the green/w red terminal (which should be for the left signal), both front and rear right side turn signals light but still do not flash. I'm trying to solve this problem a step at a time. Have found the flasher (under the seat at the rear spine of the frame) and both leads are connected as per wiring diagram. As some have indicated in previous post, the flasher may not work if it's seeing low voltage, so connected a battery charger, but still no flash. The wiring harness doesn't appear to be hacked up except for the clipping of the turn signal leads. Any suggestions on how to proceed?
 
Temporarily disconnect the flasher and replace it with a jumper wire, that will deliver a steady 12 volts to your turn signal switch. Now, sort out your power and ground wires so the lights work, finally replace the flasher unit.
 
I did as mikeinidaho suggested and bypassed the flasher with a jumper wire. I had been gaining on my turn signal problem. I took the handlebar switch apart and if I applied power with a jumper wire at the terminal inside the switch, I could get the non-working side to light, but still not flash. I determined that the contacts to that side inside the switch were only making part of the time so I set about cleaning them. They were starting to work/make more and more often, but then, I lost power to the switch altogather. I have now reverted to the wiring diagram, but I don't see any fuse in the entire harness. Can someone tell me, is there any fuse in this harness.
 
I did as mikeinidaho suggested and bypassed the flasher with a jumper wire. I had been gaining on my turn signal problem. I took the handlebar switch apart and if I applied power with a jumper wire at the terminal inside the switch, I could get the non-working side to light, but still not flash. I determined that the contacts to that side inside the switch were only making part of the time so I set about cleaning them. They were starting to work/make more and more often, but then, I lost power to the switch altogather. I have now reverted to the wiring diagram, but I don't see any fuse in the entire harness. Can someone tell me, is there any fuse in this harness.
Right near the battery
 
What has happened with the flasher warning light/socket? Also clipped off? Not sure what that might due to remaining flasher circuit....need to study the schematic.
 
Replaced the blown fuse and now have both right and left side turn signals working as they should but still, just do not flash. I have a new flasher ordered, and I expect this to complete this project. Without looking at the manual can someone tell me what size the main (one and only) fuse should be? The one that was in it was a 30 amp fuse. That seems large for a bike that doesn't have an elctric starter.
 
Have checked the workshop manual for the fuse size for my bike. It says a 35 amp (17 1/2 amp continuous rated), So what actual fuse would be correct? I know many guys, if having a ciruit problem and blowing fuses, will simply put in a bigger fuse. Everybody wants to solve their problem simply, but I'm sure most here would agree, that's a bad idea.
 
Just FYI: I have had repeated problems with flashers ceasing to work. The fix on my bike is to replace the flasher, then everything works, at least for a few months.
 
Just FYI: I have had repeated problems with flashers ceasing to work. The fix on my bike is to replace the flasher, then everything works, at least for a few months.
Wonder why they would only last a few months? Sure seems to me you'd have a circuit problem somewhere. Others may chime in here with possible causes.
 
Wonder why they would only last a few months? Sure seems to me you'd have a circuit problem somewhere. Others may chime in here with possible causes.
I have repeatedly checked the circuitry, its all good. Part of the problem may be buying $12 flashers from the auto parts store...
 
Wonder why they would only last a few months? Sure seems to me you'd have a circuit problem somewhere. Others may chime in here with possible causes.
Could be the quality of patten fasteners or undue resistance in the wires of the flasher circuit, potentially enhanced by vibration. On thing I do when I am diagnosing electical problems is to clean and use dielectric grease on each connector as I go along. They oxidize and the lucas connectors get brittle. Unless they are clean and tight they will add resistance to the circuit and this causes problems. The dielectric grease inhibits further oxidation. RESIST the impule to use conductive grease. This causes more problems by potentially creating undesired shorts.

then there is the possibility that a wire has fractured or broken, not likely but difficult to disagnose.

Good luck.
 
The stock 30 or 35 amp is the British standard rating which is the instantaneous blow rating. US fuse rating system is the max safe working amp rating. Typically the Brit rating is 2x the US rating, so a 15 to 20amp US will be about right.
 
The original flasher unit works on a bimetallic strip which heats up and bends to break contact, then it cools before bending back, hence the flashing time is amps dependant, with more amps you get more heat, and the rate of flashing is dependant on the charge of the battery plus alternator output and varies accordingly. Modern flasher units are electronic and rely on Volts, they still vary slightly but are much improved over the bimetallic strip. However they are mainly based on negative earth and so difficult to fit to a positive earth vehicle.

There are a few modern ones that can be fitted to a positive earth system and this is the one I use. I use the additional warning light circuit to drive a siren under the seat so I remember to cancel the indicators.

 
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The original flasher unit works on a bimetallic strip which heats up and bends to break contact, then it cools before bending back, hence the flashing time is amps dependant, with more amps you get more heat, and the rate of flashing is dependant on the charge of the battery plus alternator output and varies accordingly. Modern flasher units are electronic and rely on Volts, they still vary slightly but are much improved over the bimetallic strip. However they are mainly based on negative earth and so difficult to fit to a positive earth vehicle.

There are a few modern ones that can be fitted to a positive earth system and this is the one I use. I use the additional warning light circuit to drive a siren under the seat so I remember to cancel the indicators.

The bimetalic strip is essentially a resistor. Voltage = resistance x current so the flashing time is also amp dependent since the current across the flasher is proportional to the voltage drop. The original ones were quite reliable. I have vehicles that still have the original bimetallic flasher that is over 50 yrs old.
 
Finally received a replacement flasher after a long wait. The one I originally ordered (from an Ebay seller) never did show up after waiting almost 4 weeks. Was refunded by Ebay, which at least you get your money back, but then you reorder from elsewhere and wait another week plus, because of our slow postal system, and you wind up waiting over a month to get something as simple and inexpensive as this. Anyway, am happy to report that all my electrical systems, lights, horn, etc. including turn signals operate as they should. I have also done the simple charging system check of testing voltage at the battery terminals after starting and reading at idle, and compare that to voltage when increasing engine speed and see the corresponding increase in voltage to the battery. I did use the long stem turn signals at the front, and the short stem signals at the back, which seemingly wouldn't be correct as original, but I kinda like that look. Am nearly done on the mechanical/electrical restoration on this bike, and pretty much just have appearance items left that I may or may not upgrade. What breif time I did get to ride this before winter set in here in the midwest, I must admit is was a fun, great vintage sounding ride. The braking (front and rear drum) was as expected not up to modern bike standards, but if you grew up on drum brake bikes you know what to expect. Am now already starting to wrestle with whether or not to sell this bike, possibly this spring. I, as I guess many here do, have more bikes than I probably should. As age creeps up, the thought of thinning the herd before you check out creeps in. I've seen other motorcyclist that have died and their bikes be lumped in with all their other belongings at an estate sale/auction. It is usually a buyers holiday and I've seen a number of bikes be sold at these sales sell for way under what they were worth. I personally bought one nearby, years ago under that same condition, a 2006 Moto Guzzi Breva V1100 Sport, and bought what would have been a 4 thousand+ dollar bike for $1450. I guess if your dead it makes no difference, but you sorta think about the work and time you put in on your projects and don't want your spouse or family or whoever to get totally shorted on the outcome. Food for thought, but trying not to overthink it.
 
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