Topic: Slow turn signals on a 72 CB500 Update.

[drodg33]

My turn signals have always been slow on my 72 but in the past few rides they are really slow.  The battery is charged up and I have been keeping a tender on it since each ride I think this is it for the year and then like yesterday got another 30 plus mile ride in.  The lights are bright also.  Would a new flasher be a place to start?  The bike is pretty much original.  Thanks everyone. 

[Gurp]

Following.
Not sure on what but interested in the fix for it.

Sent from my LE2127 using Tapatalk

[Sw1ssdude]

The contacts on these old mechanical flashers burn up, just like on contact points. this shifts the mechanical behavior of the device. what you can do is open up the aluminium canister and very gently tweak the contacts (and marvel at the miniature mechanics inside!). Sometimes the aluminium canister is also a big capacitor (one lead being inside, the other being the aluminium canister itself, touching the connector where the green ground-cable goes). Capacitors sometimes leak electrolyte, loosing capacity or go completely defunct.

Meaning: you might be better off with a new flasher, but for originality, you can also try and repair your old flasher. gently bend the contacts closer to each other (or further apart), reassemble, and check for improvement/worsening. rinse and repeat.
If bending makes no difference, your electronics are toast. in this case, you will need a replacement.

Do you have a picture of your Flasher?

[drodg33]

The contacts on these old mechanical flashers burn up, just like on contact points. this shifts the mechanical behavior of the device. what you can do is open up the aluminium canister and very gently tweak the contacts (and marvel at the miniature mechanics inside!). Sometimes the aluminium canister is also a big capacitor (one lead being inside, the other being the aluminium canister itself, touching the connector where the green ground-cable goes). Capacitors sometimes leak electrolyte, loosing capacity or go completely defunct.

Meaning: you might be better off with a new flasher, but for originality, you can also try and repair your old flasher. gently bend the contacts closer to each other (or further apart), reassemble, and check for improvement/worsening. rinse and repeat.
If bending makes no difference, your electronics are toast. in this case, you will need a replacement.

Do you have a picture of your Flasher?

Thank you for the response.  I don't have a picture of the flasher but I can get one and post it.  Thanks again.  I am in Indiana btw and being able to ride on the Sunday before Thanksgiving is a blessing.   I think it was 56 when I left early afternoon.   

[HondaMan]

If you have the OEM flasher it will be a little rectangular box about 1cm x 2.5cm, with 2 male blades sticking out of it that 2 female plugs slip onto for installation. These little gizmos are a simple bimetallic strip with 2 electrical contacts, one on either side of the little 'blade' inside. They work like this: when current passes thru the middle strip it heats up and bends toward the non-operating side of it (backward, so to speak) until it cools off and then straightens back out so as to make the contacts touch again. Cheap to make, simple, semi-reliable.

The bug: the silver-plated electrical contacts were designed for a 10-year life, sometime during the 1970s. They are getting tired and the silver plating is flaking off the faces of those contacts, making poor contact and low current. You don't notice this, but the turn lights are dimmer than when the bike (and flasher) was new  as the result.

You can spend a lot of $$ to get the modern Chinese knockoff of this little gadget, but it will not work well nor last very long. Instead, I might suggest getting an electronic one in its place. These come in 2-terminal and 3-terminal versions: both will work, so long as you make up a ground wire for the 3rd terminal on the 3-terminal types. This terminal can connect to any Green wire in the harness, or to the frame in a bare spot where a bolt is holding something down. I installed a 2-terminal type on my 750 to try it out: it works as long as the bike's voltage is above 12.6 volts (i.e., running above 2500 RPM) but it can stall and not flash when the battery is cold or the bike is not running. The 3-terminal type will flash all the way down to about 8 volts or so, and my bike will get one of those next.

[drodg33]

If you have the OEM flasher it will be a little rectangular box about 1cm x 2.5cm, with 2 male blades sticking out of it that 2 female plugs slip onto for installation. These little gizmos are a simple bimetallic strip with 2 electrical contacts, one on either side of the little 'blade' inside. They work like this: when current passes thru the middle strip it heats up and bends toward the non-operating side of it (backward, so to speak) until it cools off and then straightens back out so as to make the contacts touch again. Cheap to make, simple, semi-reliable.

The bug: the silver-plated electrical contacts were designed for a 10-year life, sometime during the 1970s. They are getting tired and the silver plating is flaking off the faces of those contacts, making poor contact and low current. You don't notice this, but the turn lights are dimmer than when the bike (and flasher) was new  as the result.

You can spend a lot of $$ to get the modern Chinese knockoff of this little gadget, but it will not work well nor last very long. Instead, I might suggest getting an electronic one in its place. These come in 2-terminal and 3-terminal versions: both will work, so long as you make up a ground wire for the 3rd terminal on the 3-terminal types. This terminal can connect to any Green wire in the harness, or to the frame in a bare spot where a bolt is holding something down. I installed a 2-terminal type on my 750 to try it out: it works as long as the bike's voltage is above 12.6 volts (i.e., running above 2500 RPM) but it can stall and not flash when the battery is cold or the bike is not running. The 3-terminal type will flash all the way down to about 8 volts or so, and my bike will get one of those next.

Thank you so much.  I am now a little nervous on taking the side cover off without snapping anything.   Any recomendations other than being gentle?   

[SanDogDewey]

Thank you so much.  I am now a little nervous on taking the side cover off without snapping anything.   Any recomendations other than being gentle?   

Spray a little WD-40 on the rubber grommets. Release the cover one attach point at a time. Get as many fingers as you can along the sides of the attach point and gently pull. Order new grommets from Honda. The cheaper ones are not as soft.

[jlh3rd]

Thank you so much.  I am now a little nervous on taking the side cover off without snapping anything.   Any recomendations other than being gentle?   


I've got an original, unrestored, mint '75 550F. I'm extremely careful with my side covers.
all the previously mentioned points are good. I use silicon spray.
when I want to take my covers off, I use little tugs and wiggles to work one attach point off at a time. I have my finger tips as close to the point as I can. I take my time.
I use the heel of one hand directly over the attach point when putting them back on...still using gentle pressure.


I'm interested in seeing your possible original flasher....

[Johnie]

I use an electronic flasher on my 750's as HondaMan suggested. Blinking is really good even at idle. Get it at you local auto store. As far as the side covers you are wise to be nervous about it. I usually push the nipple from the back by squeezing my finger behind the cover. I don't own a CB500 so not sure how feasible that is for you. Before I put it back on i put a little lube on those nipples before I push the cover back on. 

[drodg33]

Thanks everyone and thanks for the recommendations on the side covers. 

[drodg33]

I received my new flasher unit from David Silver Spares last night and also some new grommets.  I hope that left side cover comes off okay !

[Little_Phil]

You can get in behind at least one or two of the fixings to push ii off if you are worried about cracking it.

[drodg33]

You can get in behind at least one or two of the fixings to push ii off if you are worried about cracking it.

I am worried a bit.   Thanks

[jlh3rd]

and do one post at a time......

[rotortiller]

A low wattage bulb can cause the slower flash rate with an old school flasher, as can a burnt out bulb. Dirty connections add circuit resistance and can behave in a similar manner. The flasher has a metal contact that heats and distorts thus breaking the circuit, then cools making contact and turning the bulb back on. Newer modern flashers do not behave this way by not being dependent on a margin of electrical flow. I still have the old original 40+ year old flasher which works fine still and it will stay until it dies and if I find another when it eventually croaks I will reinstall lol.

[jlh3rd]

is it a Signal Stat ?

[HondaMan]

A low wattage bulb can cause the slower flash rate with an old school flasher, as can a burnt out bulb. Dirty connections add circuit resistance and can behave in a similar manner. The flasher has a metal contact that heats and distorts thus breaking the circuit, then cools making contact and turning the bulb back on. Newer modern flashers do not behave this way by not being dependent on a margin of electrical flow. I still have the old original 40+ year old flasher which works fine still and it will stay until it dies and if I find another when it eventually croaks I will reinstall lol.

I 2nd that emotion: many shops lately have been selling incorrect lamps for the turn signals. The bulb should be 23w, not 7w (or less than 16w) like a 'running light', or else it does not draw enough power to heat up the old-style thermal flashers and make them flash.

But...the 500/550 also suffers low voltage often (here in the USA) because of the headlight having to be ON while riding (thanks to Jimmy Carter and his DOT...), and when the running voltage at the flasher drops below 12.0 volts they seldom flash. The little bullet connectors throughout the whole wire harness are now 40+ years beyond their intended service life, too: they were/are zinc-plated steel plugs/sockets, and the zinc is flaking off now. This makes a nice insulator, so the connectors drop voltage everywhere in the bike. This can be alleviated somewhat by unplugging each one and adding a drop of LPS-1 (not LPS-2 or 2.5, or 3, nor any other type of product: this is unique) into each plug. This magic spray is hard to find, but worth the effort: I have a 7 ounce can I bought in the 1980s, which is still more than 3/4 full! It also comes in 1-ounce spray cans, enough for most folk's lifetime.

[jonda500]

The bulbs readily available here are always 21w which don't draw enough current to trigger flashing at idle speed with the oem flasher can. I came across two 27w bulbs in my stash so I swapped out the two front bulbs and now have flashing at idle speed albeit very slow (I prefer the slow flash rate over quick flash of the modern cans).
John

[Deltarider]

Yes, the rate of flashing varies with the wattage. On mine I can even note the difference between 18 Watts (OEM) and the more common 21 Watts that most shops have in stock. If you check the parts lists, you will see the wattage differed from country to country and Honda equipped their models with flasher relays accordingly. Just check what it says on the flasher. Markets had: 18W, 23W and 27W and France even had 10W on their CB350Fs. Do not conclude a 23W will emit more light than say a 21W. The design also matters and some bulbs are better quality than others and consume less. Philips Longlife Ecovision bulbs are well designed and are a good choice.

[bryanj]

Also remember some parts list quote in CP, Candle Power not watts

[drodg33]

Thanks everyone. 

[HondaMan]

Philips Longlife Ecovision bulbs are well designed and are a good choice.

Are those a 'normal' filament-type bulb, too?

[Deltarider]

Philips Longlife Ecovision bulbs are well designed and are a good choice.

Are those a 'normal' filament-type bulb, too?

Philips used to have a range of longlife eco bulbs in all sizes for all fittings. They had improved however normal looking filaments and bulbs were filled with a special gas. Some drew 20% less current while offering the same or better light. Alas, I'm afraid most of them are NA. Background is that Philips has split its activities* and handed over practically all its divisions to other parties and the brand Philips now concentrates on professional medical equipment for hospitals and the like. It's a pity; the list of inventions Philips has done in the past is almost endless. They invented: the Compact Cassette, the CD, the DVD, just to mention a few. When the competition from Asia increased and increased, Philips choose to concentrate on offering better quality. "Let's make things better", has been their slogan for years. That strategy has not been succesful in all markets; some markets will always go for the cheapest junk.

* ASML is a daughter of Philips and has become the world's leading manufacturer of chipmaking machines. Their 'extreme violet technology' is unmatched - some wiring patterns of just one atom thick - and has made them Europe's most valuable enterprise.
Periodically the US are on their knees, begging the Dutch government not to allow export of these machines to China. Also ASM, another descendant of Philips, is in chips making and is, as we speak, building a huge plant in Phoenix, AZ.

[HondaMan]

Philips Longlife Ecovision bulbs are well designed and are a good choice.

Are those a 'normal' filament-type bulb, too?

Philips used to have a range of longlife eco bulbs in all sizes for all fittings. They had improved however normal looking filaments and bulbs were filled with a special gas. Some drew 20% less current while offering the same or better light. Alas, I'm afraid most of them are NA. Background is that Philips has split its activities* and handed over practically all its divisions to other parties and the brand Philips now concentrates on professional medical equipment for hospitals and the like. It's a pity; the list of inventions Philips has done in the past is almost endless. They invented: the Compact Cassette, the CD, the DVD, just to mention a few. When the competition from Asia increased and increased, Philips choose to concentrate on offering better quality. "Let's make things better", has been their slogan for years. That strategy has not been succesful in all markets; some markets will always go for the cheapest junk.

* ASML is a daughter of Philips and has become the world's leading manufacturer of chipmaking machines. Their 'extreme violet technology' is unmatched - some wiring patterns of just one atom thick - and has made them Europe's most valuable enterprise.
Periodically the US are on their knees, begging the Dutch government not to allow export of these machines to China. Also ASM, another descendant of Philips, is in chips making and is, as we speak, building a huge plant in Phoenix, AZ.

Yeah, Philips has long been a 'go-to' company for tech: I used many of their products in Controls Engineering for years.
Something you just mentioned, though, explains why I have seen some of the things I have lately, from several manufacturers: the 1-atom conductive layer. That approach works OK in so-called 'normal' electronics, usually denoted as "commercial" temperature range products (0-70 degrees C operation environment). But when we built some equipment not long ago that included some of the Philips circuitry devices for an application that could be left outdoors sometimes, it failed after the 2nd 'cold spell' it suffered, and the problem was in the circuit boards that I noticed included Philips components (those replaced some National Semiconductor parts that used to be there). A 1-atom layer conductive path would exactly explain the failure scenario we saw: the solution became to add heaters to the area (after replacing the electronics) for sub-30 degrees (F) situations, and insulating those boards especially so they would stay warmer when not in use.

Thanks for the clue! I'm going to relay that to the guys I worked with: it is still, AFAIK, an "unresolved" failure because the maker of the controller that used those Philips components in their product doesn't know about that construction. They will need to redesign their PC boards to include different types of semiconductors in order to solve it for a "no power" winter cold shutdown situation.

(In case you didn't already know, I used to have to do 'fault tree analysis' for such failures, being trained in the Apollo program, and have done it for several industries. Lucrative work!)

[drodg33]

Thanks for the info and the info on the Phillips bulbs.   

[MauiK3]

Very interesting stuff here.

[drodg33]

I just wanted to update on the slow flashers.  We just replaced the flasher with a new unit from David Silver and cleaned up the contacts and it makes a huge difference on the flashing.  Its like what I could consider normal.  Thanks everyone for your input on this, I know it has been a few months ago now.   

[HondaMan]

I just wanted to update on the slow flashers.  We just replaced the flasher with a new unit from David Silver and cleaned up the contacts and it makes a huge difference on the flashing.  Its like what I could consider normal.  Thanks everyone for your input on this, I know it has been a few months ago now.   

Good job! When all new it will last quite a few years, usually.

[drodg33]

I just wanted to update on the slow flashers.  We just replaced the flasher with a new unit from David Silver and cleaned up the contacts and it makes a huge difference on the flashing.  Its like what I could consider normal.  Thanks everyone for your input on this, I know it has been a few months ago now.   

Good job! When all new it will last quite a few years, usually.

Thanks!!