Project 1934 VG 500

[AlbertR]

Hello, thanks for the follow up.

I finished mounting the carburettor. About those ugly threads on the cap, since it screws in just fine, I'm not very confident about trying to bend it back into shape. I have a feeling this aluminum alloy will just break at any moment.

I will try to see if it leaks, and just leave it as is if it doesnt.

I'm not sure if this throttle slide might need replacement or not, it looks a bit worn out.

However i'm a bit confused as it currently mounts a throttle sldie "6/3" and i'm reading that it should have a "6/4". Should i keep the 6/3 for a richer mixture? maybe compensates a bit the effect of ethanol in the fuel?

[AlbertR]

This week i was mostly busy reading the workshop manual and making a list of the missing spares.

I also already ordered engine oill, some CASTROL CLASSIC GP50, and i have been trying to source some grease for the BA gearbox,. I've been trying to source Morris K400EP or Penrite Semi Fluid Grease here but its not possible.
So checking specs and with the aid of my local dealer i got a can of some EP 00 semi-fluid grease that seamed feasible.

I also received already the cotton-braided cable.

So my plan now is to have a look at the gearbox, i need to strip it down to check if everything is okay (it should have new spares in there according to the previous owner) mount it back to the bike, and then get the magdymo timed up and prepare for starting the engine for the first time. It has been rebuilt, so i want to make sure there's plenty of oil in the system before attempting any startup

[simon.holyfield]

Hello, thanks for the follow up.

I finished mounting the carburettor. About those ugly threads on the cap, since it screws in just fine, I'm not very confident about trying to bend it back into shape. I have a feeling this aluminum alloy will just break at any moment.

I will try to see if it leaks, and just leave it as is if it doesnt.

I'm not sure if this throttle slide might need replacement or not, it looks a bit worn out.

However i'm a bit confused as it currently mounts a throttle sldie "6/3" and i'm reading that it should have a "6/4". Should i keep the 6/3 for a richer mixture? maybe compensates a bit the effect of ethanol in the fuel?

For what it's worth, the float chamber cap on my W/NG has distorted threads like that and it's just fine. Like you, I didn't fancy trying to bend it back - as long as you can tighten the cap OK, I'd leave it. Incidentally, I must have left my cap loose once - I rode 26 miles before I realised it was sitting on top of the gearbox!

On the slide: if you fit it in the body with the spring & the cap on, you can feel the play. If you put your finger through the bell mouth and into the cutaway try and move the slide toward the inlet valve & away again - a good slide will hardly move. If you can feel much movement - say more than half a mm or so, it's had it... the bike will run, but you probably won't get a very nice idle!

If you have to replace it I would get the right size - they are readily available - but for your first start, it will be fine. You are unlikely to notice the difference between a 3 cutaway and a 4 cutaway until you are on the road.

[AlbertR]

Hello, thanks for the follow up.

I finished mounting the carburettor. About those ugly threads on the cap, since it screws in just fine, I'm not very confident about trying to bend it back into shape. I have a feeling this aluminum alloy will just break at any moment.

I will try to see if it leaks, and just leave it as is if it doesnt.

I'm not sure if this throttle slide might need replacement or not, it looks a bit worn out.

However i'm a bit confused as it currently mounts a throttle sldie "6/3" and i'm reading that it should have a "6/4". Should i keep the 6/3 for a richer mixture? maybe compensates a bit the effect of ethanol in the fuel?

For what it's worth, the float chamber cap on my W/NG has distorted threads like that and it's just fine. Like you, I didn't fancy trying to bend it back - as long as you can tighten the cap OK, I'd leave it. Incidentally, I must have left my cap loose once - I rode 26 miles before I realised it was sitting on top of the gearbox!

On the slide: if you fit it in the body with the spring & the cap on, you can feel the play. If you put your finger through the bell mouth and into the cutaway try and move the slide toward the inlet valve & away again - a good slide will hardly move. If you can feel much movement - say more than half a mm or so, it's had it... the bike will run, but you probably won't get a very nice idle!

If you have to replace it I would get the right size - they are readily available - but for your first start, it will be fine. You are unlikely to notice the difference between a 3 cutaway and a 4 cutaway until you are on the road.

Hi Simes thanks so much for your input!
I'll check the play of the slide valve as you mention,
I hope to get my hands on the gearbox this saturday

[garycullen]

Alfred, I hope you are aware of some nasty chemicals that can exist in EP greases.
This from a google search assisted by mr AI:
The Attack on Bronze: Instead of cleanly protecting the surface, active sulfur aggressively reacts with the copper in the bronze. This forms copper sulfide and copper disulfide. These crystalline compounds cause pitting, spalling, and rapid abrasive wear on soft yellow metals.

When I refurbished my BA box several years ago now I got some good advice from Nev, a frequent poster here.
I use a locally made up runny grease product without any Sulfur in it.
I believe prenrite make a fluid grease product for veteran and vintage cars without Sulfur.
I use the locally made up one in my 1933 Austin 10 steering box and the BA box on my VB. So far no problems.

[AlbertR]

Alfred, I hope you are aware of some nasty chemicals that can exist in EP greases.
This from a google search assisted by mr AI:
The Attack on Bronze: Instead of cleanly protecting the surface, active sulfur aggressively reacts with the copper in the bronze. This forms copper sulfide and copper disulfide. These crystalline compounds cause pitting, spalling, and rapid abrasive wear on soft yellow metals.

When I refurbished my BA box several years ago now I got some good advice from Nev, a frequent poster here.
I use a locally made up runny grease product without any Sulfur in it.
I believe prenrite make a fluid grease product for veteran and vintage cars without Sulfur.
I use the locally made up one in my 1933 Austin 10 steering box and the BA box on my VB. So far no problems.

Hi Gary thanks for your input. I'm aware of this. The manufacturer of the SIL GREASE L-EP 00 actually states a copper corrosion result of "Class 1 max. after 24 h at 100°C", according to ISO 2160 / ASTM D130, which is reassuring. However I’ll try to replicate at home, but using a piece of bronze as well as copper, cover them with grease and just leave them at around 100°C for several days, checking for staining, darkening, pitting or any other surface attack.
It obviously will not be a certified test, but it should be a useful comparative check. I'll try to look in the boxes if i can find the old bushes and use them for the test.
I’m a chemist by training, so I quite enjoy this sort of thing anyway! I’ll post the results here once I’ve done it.
Thanks also for the warning about active sulphur, that was precisely what made me look more carefully into the grease specification before filling the gearbox.

[simon.holyfield]

I’m a chemist by training, so I quite enjoy this sort of thing anyway! I’ll post the results here once I’ve done it.

Now we know you are an expert we will bombard you with questions!