Engine blown - Cylinder spigot fractured

[BSA_54A10]

Afaik SRM had a batch made in the 80s and anounced production of a new batch 3 or 4 years ago, so they should have some sort of patterns or dies, whatever technology they are cast with.
The greatest problem definitely is financing the thing as you say, and how to gauge interest? For sure it's nothing you can sell hundreds of in short order, rather a constant trickle I'd suppose.
Prices are rising however, just last night a thick flange set went on ebay US for more than 500 USD, in good condition (no broken fins, but followers seized/rusted in place) and on a well worn STD bore though.

Well more like just not enough profit.
The simple trick s to give the pattern to your local grey iron founder with instructions to pour a couple from the wash when you are going to empty the furnace ( usually done when there is a change of alloy ).
I used to buy a lot of iron castings and that is the way we did it for next to nothing and most foundries are just begging for these little jobs to nest in with bigger ones.
Ordering a batch run is a different thing.
Same with machining.
Drop them off with the instruction " when the boys have nothing on " again most machine shops would give their eye teeth to have some down time jobs sitting on the shelves

[bsa-bill]

A guy at Selkirk vintage meeting has been selling new barrels for a couple of years, mostly Triumph but others too (IIRC Norton Vello ??) so they are being made somewhere, never heard anyone speak of them though so quality????,  from memory I think cost was reasonable

[Duncan R]

Thanks for the encouragement and the wealth of info.

Just to confirm a few things

Re lining if done properly (say SRM) is acceptable and reliable

Thin flange barrels on low comp 7:25 is ok - the worst that can happen is the flange cracking , the spigots don't break off?

Is there much loss of power/performance between running 6:25 and 7:25 pistons

Thanks again

[Duncan R]

Sorry another question - do the barrels off a Ariel Huntmaster fit an A10? 

[Topdad]

Amen to that Markus, would solve alot of problems for people regards Bobh.

[duTch]

Oh the moments, thanks Brian-- I think I'll just bypass a few and check the fridge!!--yup- all good,and now  I'm inclined to agree with the idea that only the busted side has been lined, with the original casting totally carved off, evidence being there is a further bevel from the original one next to the 'spigot'. Additionally, I had a feeling my barrel has a liner, so just had another look,and a photo and what I would figure is a traditional liner(thickness) is apparent by the broken casting which I hope doesn't cause problems.
  My thick flange also measures a half inch~photo attached somwhere ,hope it works.
 Good luck ,duTch

[olev]

Is there a reason no-one has made a set of alloy barrels for A10s?
cheers

[melville]

Is there a reason no-one has made a set of alloy barrels for A10s?
cheers

Just single barrels, as used on VW or Porsche or BMW, can run $700 each OEM or aftermarket.  Clearly the A10 barrel is a much more complicated unit, with two bores, flanges, and a lifter block included.

However, if a barrel that needs work goes for >$500, the market may be coming.

[trevinoz]

Duncan,
                The Huntmaster barrel fits but is the wrong shape, somewhere between a plunger barrel and swinging arm.
I would imagine that Huntmaster barrels are harder to get than A10.
    Trev.

[chaterlea25]

Hi All,
I hope to travel over to SRM on Thusday weather and ferry permitting, The bottom end of the RGS engine is sorted 
I will ask if there is any progress on cylinders
last time I asked,there had been lots of problems with the casting processes

With modern CNC machining I would think that machining alloy barrels would be viable ??
I dont know if the spigots would be strong enough in alloy to allow nikasil bores or would liners be needed
I would certainly be interested in (road testing)  a set LOL

Cheers
John O R

[RichardL]

Yes, I think the Forum would amount to over 200 beta testers.

In thinking about alloy, it seems to me that sleeves are an absolute (now that I've said that, I'm bound to be wrong), then, because the meat of the casting would be thin around the sleeves, the high coefficient of exansion of aluminum would let the sleeves loose. If I understand this correctly, in automotive aluminum blocks, the meat around the sleeves is thick enough that it does not expand so much, versus the sleeve.

In all our talking about this, it got me to thinking of a foundry in Tijauna, MX I used to do business with in the '70's. We were making aluminum loudspeaker frames, but they also do cast iron. I looked them up and they are still around (quite successful, actually) and on the internet. The guy who was my contact there is now a big-time name in Tijuana business. I'm thinking of contacting him to see if he is a vinatge motorcycle enthusiast. They could definately make the castings, but I am somewhat pipe-dreaming.

Richard L.

[Duncan R]

Gary from SRM emailed me back with a quote for relining today, he mentioned the new cylinders and he reckoned they would come in at about £700

Trev,
There is a set of Huntmaster barrels on USA EBay, cosmetically challenged but no broken fins and on Std bore for $99 buy it now, seller said he could get the postage down to $100 using normal post

[melville]

With modern CNC machining I would think that machining alloy barrels would be viable ??
I dont know if the spigots would be strong enough in alloy to allow nikasil bores or would liners be needed
I would certainly be interested in (road testing)  a set ex LOL

Yes, I think the Forum would amount to over 200 beta testers.

In thinking about alloy, it seems to me that sleeves are an absolute (now that I've said that, I'm bound to be wrong), then, because the meat of the casting would be thin around the sleeves, the high coefficient of exansion of aluminum would let the sleeves loose. If I understand this correctly, in automotive aluminum blocks, the meat around the sleeves is thick enough that it does not expand so much, versus the sleeve.

In all our talking about this, it got me to thinking of a foundry in Tijauna, MX I used to do business with in the '70's. We were making aluminum loudspeaker frames, but they also do cast iron. I looked them up and they are still around (quite successful, actually) and on the internet. The guy who was my contact there is now a big-time name in Tijuana business. I'm thinking of contacting him to see if he is a vinatge motorcycle enthusiast. They could definately make the castings, but I am somewhat pipe-dreaming.

Richard L.

No need to go to TJ--these guys are local to you (manosound):

https://www.lnengineering.com/

And they do the CNC alloy linerless stuff that chaterlea wondered about.

[MG]

Gary from SRM emailed me back with a quote for relining today, he mentioned the new cylinders and he reckoned they would come in at about £700

700 quid???
Blimey, I'd have thought 450, maybe 500 quid. Did he also mention WHEN they are going to come in (at about £700  )?

No need to go to Tijuana (except for reduced costs maybe), there are many excellent foundries in the UK, with loads of experience in casting grey and nodular iron, just thinking of ADI Treaments in the West Midlands.
Just judging by feeling without doing any maths, so could be totally wrong, but I think without through-bolting an aluminium casting wouldn't be up to the job, especially in the bottom flange area. Only chance I see is casting a nodular iron part, incorporating the liners and mounting flange in one piece (maybe even a top flange for the head mounting threads), and then cast aluminium around it, more or less only the fins. Just daydreaming anyway...

Cheers, Markus

[Duncan R]

Hi Markus,

He just said that they were considering re-making but are evaluating costs.