I would think that one should be able to purchase a genuine cover for the same price. British metallurgy will be superior and it would be guaranteed to fit. Every Indian made item I've purchased has needed some modification to make it fit. Granted there are good repro suppliers based in India but the problem is they tend to be lost among the lower quality ones. At 150 quid with shipping, I'm sure you could source genuine. I probably have one somewhere if you need.

email (option): cas.vanderwoude@gmail.com

I don't need one myself, but it is one of those parts which is becoming difficult to find and if this hobby is going to continue new spare parts will have to be made.

And it should be a relatively easy thing to cast with a minimum of machining required.

And unlike girder forks if it fails it shouldn't leave anyone chewing the road.

Rob

email (option): robmiller11(a)yahoo.co.uk

['And it should be a relatively easy thing to cast with a minimum of machining required..']

I agree the future of this hobby is in replication as the sources of original parts dry up and demand, it seems, continues to increase..In fact most of the bikes out there already have a number of such parts...

However, without going into the casting itself...

Don't underestimate the amount of machining required and the accuracy of that machining to ensure the cover fits, the bushes have the correct interference fit, the clutch arm and pin fit correctly, the dowels fit correctly, the clutch pushrod aligns correctly, the retaining screws fit, the clutch cable fits, the kickstart quadrant and spring have the required clearance, the spring retaining screw fits and all of those elements are dimensionally correct in relation to each other...

To achieve that and to machine 'as cast' new castings, detailed toleranced drawings and accurately made machining jigs are also required, along with good machine tools and tooling, skilled operators and a functional quality control regime at every stage...Also a good knowledge of the specifications of all the components related to the cover itself..

Now that's not to say it's impossible, or that the Indians couldn't manage it...though experience indicates that's not likely...

Products that appear 'simple' are frequently not as simple as they appear when it comes down to assessing them from a manufacturing viewpoint...Ian

email (option): ian@wright52.plus.com

Ian Wright

Products that appear 'simple' are frequently not as simple as they appear when it comes down to assessing them from a manufacturing viewpoint...Ian

email (option): ronpier@talk21.com

Gees, it is not that hard.
I would hate to even try and count the number of parts I have cast over the years.
You only need jigs & fixtures if you are mass producing them and I doubt even a 3rd class machinist got any where near an original BSA gear box.
As for tollerances , the originals were not all that good which is why so many have index marks on them so they can be reassembled mated to the inner they were bolted to when the shaft holes were cut.

email (option): bsansw1@tpg.com.au

Fair do's! But mass production is not on any agenda for me. A run of 5, 10 or even 25 is as much as I want to cope with. I try to take upfront orders to produce the right batch amount and nearly always get something left over that hangs on for ages. Some people would simply not realise just how much time, effort, jigging and making fixtures goes into machining something like those small awkward shape parts like the Vokes elbow or Norton bump stops. And that's after the agg of dealing with the foundry. Next time someone asks me for those parts, I'll point them to you.
Ron

email (option): ronpier@talk21.com

'One off' or very small batch parts manufacture can be achieved by doing individual, improvised set ups for each operation..
That, however, is completely impractical for volume or series production as it multiplies production times and therefore the costs immeasurably...

A batch of 50 components, for example, with 20 or so machining and set up operations on each part would require 1000 separate set ups...

That is the whole point of 'jigging' components after the first machining operation has been carried out, the purpose of which is to establish a datum face to work from for subsequent operations and to introduce consistency......

I think it's plain enough to deduce from the low standard of the bulk of Indian replica parts production that the standard engineering practices and methods required to produce the consistently good quality, accurate series production needed for even 'simple' components is not followed...

Further, consistent quality control standards are plainly not applied either in the majority of cases it seems...

A browse through the tolerances and fits contained within the 'standards' book for the M20 illustrates that BSA were holding good tolerances for the period over a wide range of parts, over production numbers of hundreds of thousands in many cases and over a period of YEARS of production......

This means the correct manufacturing and inspection methods were employed and the idea that everything was produced by third rate (at best) machinists is frankly, laughable...

Don't forget BSA didn't just make the parts, they made many of the machine tools and the tooling employed in the manufacture of those parts as well...

Returning to the original subject of this post to my mind there is nothing to indicate that the Indians have 'raised their game' for the manufacture of this particular component and I consider the risks inherent in the purchase of ANY Indian component remain unaltered...

I also don't consider the gearbox outer cover an 'easy' part to cast and manufacture...If it was we'd all be getting them and other parts made but we're not...

To illustrate my point consider this...What are the correct machining dimensions and tolerances for all the machined faces/bores etc. of the cover and the sizes and tolerances for the all the parts that have to fit into it?...Ian

email (option): ian@wright52.plus.com

First off BSA were made by production line process workers, not qualified & trained machinists.
All any of them did , apart from the fitter machinists in the mechanical rectification section was to measure what came off the machine using go /no go jigs then stamp the appropriate number on the part, or place it in the appropriate stillage.
Skilled tool setters set each machine up, but unskilled / semi skilled process workers actually did the machining.

As for 1 offs ( which is what I usually do ) it is not difficult, just time consuming.
I did 3 gearbox ends for my 2 speed & 3 speed boxes on the round tanks because the clutch supports were all broken and it was easier to make a whole new one that to faf around trying to build up weld then machine down and in any case the aluminium has fully age hardened so would have required heat treating to regain 50% of its original strength.

The longest and hardest part was preparring the best of the broken originals to be used for the silicon mould to make the wax masters for the lost wax moulding in a plaster mould.
That took about a week
casting took about 3 hours
Machining about a day each, no jigs, just measuring and marking.

If I was to do 50 then jigs would make things a little easier but one would have to be looking at a run of 100 or more before it would be worth while making them.

And yes they all fitted , no worse that the originals and I put steel pins int the clutch pivot arms so they should never cause any grief.

One of them got sold to a friend and I know he is happy with it.
and yes you can tell they are repos, the logos are not as sharp or clean as the originals were , but they work and that is all they needed to do.
The other two went on evilbay after she decided she could not live with me any more so I have no idea how they ae traveling.

email (option): bsansw1@tpg.com.au

Ah yes indeed Trevor. Making a one off or even an extra one or two for mates is fine as you are not factoring in your labour. But to make a small batch as usable repros for other enthusiasts to buy can get costly.

By the time I've produced some sort of pattern and then paid the foundry with postage both ways, then worked with my Machinist (who works at 'Mates Rates') to organise the best process and fixtures needed, With all the running around, to then produce a small item for say £65......I recon if I needed the money I'd be better off pushing trolleys around Tesco's car park for a few hours a week. Ron

email (option): ronpier@talk21.com

Arh yes.
making a profit is a different matter all together.
Been looking at a way to make a living out of BSA's down here for 40 years.
No troubles making some beer money , but a living no chance.
The last British bike shop in Sydney is currently up for sale.

OTOH you might like to try casting yourself, it is not as hard as people imagine.
We have been doing it for better than 2000 years and the first 1800 it was all suck it and see.

All you need to do is to keep 2 bins of scrap aluminium.
One for die cast and one for sandcast.
Add 10% by weight silicon hardener ( 20% to 25% Si ) to diecast aluminium and about 1/2 that to sand cast

email (option): bsansw1@tpg.com.au

Hello All,

To respond to the original topic about whether or not to buy an India-made outer gearbox cover I would have to say absolutely not, unless you enjoy grief.

I do not know the specific vendor, so perhaps I'm being unkind. All I can say is that everything I've bought from India, whether for Enfields or WM20s, has been off in some way. Naively I bought a fair amount of stuff and then when it came time to fit it... nothing would fit properly.

I bought some items through eBay and returned a few (for a refund). Some took so long to arrive that I found I had no recourse when they did get here. Sometimes the vendor had ceased to exist when I complained.

I won't bore you with all the stories.

Allan

email (option): allanmatchless@yahoo.com