Thanks Al.  Incredibly kind of you. Message sent.

Indicators arrived as did headlamp sealed beam.  Fitted front indicators and chopped down the incredibly long studs they came fitted with, but discovered I only have one M8 dome nut left in my stock of nuts n bolts.  Hate leaving the long standard studs stuck up with normal full nuts on them.

New stainless dome nuts on order.

Indicators also supplied with 6v/21w bulbs and they should be 6v/18w.  The flasher can will probably flash way too fast with 21w fitted, so a box of 18w bulbs on order.
They do light up though, as does the repeater on the speedo; but do not flash as I have not yet fitted the rear indicators.

I need to fabricate a steel bracket for them with the original brackets long absent.
There is a long steel plate in my now redundant hand brace that seem to be just the right width and thickness to cut in half, bend and shape, so indicator mounts courtesy of the NHS.

I fitted the sealed beam in headlamp rim, fitted two W clips to hold in place and connected it up to the bike.

Kick over - started on first kick again, so that particular gremlin has been given the boot, start up, headlight switch on and we have dip and high beam with a working blue high beam indicator on the speedo.

Headlamp working, but not buttoned up yet.  I need to investigate horn malfunction yet.  I suspect it is the horn itself, rather than the wiring or switch, but knowing my luck, I would button up the headlamp only to have to remove it again, and in doing so disturb something else.  Also going to run a separate headlamp ground to the headlamp shell bolt.  I do not like the idea of one ground wire fitted with a four way connection for three other grounds to connect to in the shell.  In my view, high wattage items like headlamps should have a dedicated ground.  Just my opinion.

Front indicators fitted.  Left ( on pic ) fitted with dome nut.  Right has its silly long stud chopped down but still has supplied full nut fitted.  Lenses removed waiting for bulbs arriving.



Silly long stud they come supplied with.  They could have your eye out.


 

Tinkicker, Alan put me onto This email address is being protected from spambots. You need JavaScript enabled to view it. at the Aircooled RD Club for a dating certificate.
He did the last one for me really quickly and charged me £30.

Thanks Pete.

I will send him an email.  Of course I have any number of photos....

I just finished looking at the horn.  I got a little more response from it by playing with the tone screw again, but I think the points are corroded inside.  Seeing 6v at the terminals when switch is pressed.

Best I got from it is a noise like a strangulated roadrunner.... What a shame.

Now I know the horn is being a little recalcitrant, I ordered another with dual bolt fixing on the bracket and 28mm spacing between centres.  Putting a ruler across the forks legs in front of the bracket, closing one eye and effecting a squint, I make that about right.

Shame about the horn, I would have liked to keep it, but chancy with it being intermittent.  If you get pulled over on an old, MOT exempt bike (over 40 years old, they are classed as historic vehicles and road tax and MOT exempt), one of the first things a cop is going to ask is for you to try the horn.  It may be free of the annual MOT inspection, but it must be kept fully roadworthy at all times.  An inoperative horn will attract a ticket.

Made a new dedicated ground just for the headlight.  I do not like the idea of running multiple grounds from a thin, almost 50 year old wire, when one of those systems connected to it is the headlamp.
Headlamp now secured in the housing.

New 18w BA15S bulbs arrived and fitted in the indicators.  Charged battery fully and tested with rear wired in.  Unfortunately, although everything lights and works fine, they do not flash.  I get the initial "boing" noise then they just stay lit.
Again disappointing, I would have liked to have kept the original can, but I can remember from my youth, that that particular style of can was quite unreliable.  I can remember changing one on my mates TY50 and again on my own FS1E.  Both for the lights staying lit.  New modern type of three pin ordered. 

Indicators and telltale lit, but no action.

Modern three pin is almost certainly not the same.

One wire is ground on the Yamaha flasher. On modern three wire the third wire is "P" or "pilot" for the instrument lamp and is hot when lights flash. Connecting "P" to ground creates a direct short.

You should be able to insulate the "P" and use it as a two wire... unless you found a modern flasher that has the ground terminal and not the "P" terminal.

P.S.  Yamaha did not need a "P" flasher because they used the ingenious wiring of running the left and right power wires to the low wattage pilot bulb in the gauge...  the bulb grounds through the opposite side lights...  i.e. when "left" is selected, the tiny pilot bulb is grounded through the right side bulbs.  Works great with high wattage bulbs because the tiny current flowing through the pilot bulb is not nearly enough to light the right side bulbs when left is selected...  until someone installs low wattage LED bulbs in the four indicators.  Then all four lights will flash.

Well that copy paste did not work well. 

Thanks mark. The one I have ordered is specifically for early 6v Yamahas.

Fingers crossed!  Every three pin I've bought where seller claims it's correct for the old 6v three pin Yamaha sells the wrong part.  Some claim it's electrical and cannot be returned. 

I gave up trying years ago so perhaps someone does supply the correct type these days?

One can but try.  I have not had any luck with aftermarket on this bike.  I am heartened that looking on his classic bike website he has two 6v / 3 pin flasher cans advertised.

One I bought advertised for DT100

The second stating the pinouts:
Connections:
X = battery
L = Switch
P = Indicator light.

From what you stated earlier, I am hoping that this means he knows the difference.

I have to confess, I did not know the difference until you mentioned it. 

I will be the guinea pig.  If it works I will put up a link so everyone knows its a winner.
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