Dynamo Regulators dynamo belt pulley

[Greybeard]

I changed the dynamo pulley on my bike this morning.
I followed the fitting advice and allowed a twist of 45° each way on the bottom run.
https://youtu.be/WpAAWnoPp2I

This is almost certainly the last bit of tinkering I will do on that motorcycle.

PS., while I'm here, do you have any idea what that little screw is doing in the timing case; it was there when I bought the bike. I can only surmise it's something to do with the A&R unit. The hole for the screw is only about 2mm.

PPS. In the next picture you can see the 'High Capacity' steel/iron bodied oil pump I fitted when I was restoring the bike.

[tomkilde]

My A10 came with a similar screw just above the dynamo sprocket.  I assume a previous owner wanted to be able oil the chain without removing the timing cover?

PS this is an older photo.  The bike was completed last summer but our Canadian neighbors have sent us a blast of arctic air and it's too cold to go out to the garage right now to take a fresh photo.

[Greybeard]

My A10 came with a similar screw just above the dynamo sprocket.  I assume a previous owner wanted to be able oil the chain without removing the timing cover?

Maybe someone thought a drop of Three-in-one would quieten the A&R unit on my bike.

[muskrat]

G'day GB.
Might have been used to lock the pinion to adjust the points.
Cheers

ps I'm sober now!

[Greybeard]

G'day GB.
Might have been used to lock the pinion to adjust the points.

I wonder though because the hole is tiddly.

ps I'm sober now!

You'r posts from last night were hilarious 😆

[bikerbob]

You may be right about lubrication as the original manual for a 1950 A10 0n page 16 states that every 2000 miles remove timing case and check A/R unit and lubricate if needed with light oil. So maybe a previous owner thought it was important and put that hole there so he could  lubricate periodically without removing the timing case.

[Jules]

At least the screw on GB's bike is not very obvious, Tom, your restoration looks really sharp, I hope you did something better with that ugly brass plug! 

[dave55]

Apparently Tufnol or Phenol formaldehyde resin gears do not need lubrication ,.....But last longer with a drop of oil on them every now and again.

[RDfella]

I hope you did something better with that ugly brass plug!

Yeah, swap it for one of those old sight-glass drippers 

[Slymo]

Question: I can't help but wonder if the belt drive conversions put more side thrust on the dynamo body? The chain drive has a bit of slack in it but with a belt I imagine it has to be close to tight. Is this likely to flog out the rather small bearing at the drive end of the dyno?
S.

[groily]

Question: I can't help but wonder if the belt drive conversions put more side thrust on the dynamo body? The chain drive has a bit of slack in it but with a belt I imagine it has to be close to tight. Is this likely to flog out the rather small bearing at the drive end of the dyno?
S.

Don't think it's a concern. Did 50K miles on my A with belt drive (SRM then the Dynamo Regulators kit which is chunkier) and never even touched the dynamo after an initial overhaul when I bought the bike. (Saved any more alloy being eaten off the inner timing cover by the chain drive  . . .)
Correct belt tension is important though - see previous threads on here.