Ariel Owners Motorcycle Club

The guy who made the cylinders for John is still making as far as I know.

Ian.Taylor wrote: ↑Wed Feb 28, 2024 1:33 am I finally got around to installing the VHA liner into my spare VHA cylinder.
Heated cylinder, cooled the liner in a snow bank.
When the cylinder was hot the liner was wiped down and it dropped in nicely with a clang as the spigot touched the cylinder.
I used 3 T120 cylinders stacked to weigh the liner down.
Once cooled there is a gap of .004 between the cylinder and spigot.

Ian,
Here's a pic of my VHA cylinder. Not been fully re-sleeved as far as I can tell but a thinner standard liner has been fitted inside the original. Looks like the piston seized and split the thinner liner.
Anyway, clearance between liner spigot and barrel about 8 thou

There should not be a gap there

Mar 3 here in Eastern Ontario was a beautiful 60f .
I just had to get the VHA out for a ride plus I was curious as to what Temps they run at.
Sure beats the winter blues right ?

After a 45 mile ride mostly at 50-55 mph these are the Heat/temp readings I got.
Exh rocker box 240f
Exhaust area approx 240f
RH side of the cylinder just below the head 230f

1/2 way down 210-15 f

Bottom at pushrod tunnel big drop at around 160
Crankcase 100f

Reading were very close on opposite side.
Intake track 150f

you will find that nikasil is not suitable for coating direct onto the aluminium of existing Ariel cylinders. I tried and it failed, and others I know that have had other makes of older cast cylinders nikasil lined direct onto the aluminium have also had failures. Nikasil is however ok on new high quality castings or better still on cylinders made from billet.
David

Good info to know David !

Mike Dickson was the guy who made the HS cylinders, primarily for the trials fraternity. Unfortunatly he too passed on and the business went to his son. I believe it has been sold again and have been told that quality has suffered. I have no contact details but would take a chance if some kind person would supply. I was at Shepton Mallet last w/e and found an almost complete but very rusty old HS engine in bits. Head was a std 500, welded up fins, plugged and re-drilled rocker box holes and welded up combustion chamber due to some past catastrophe. The asking price was astronomical. I visited JB a couple of months before he passed and I am so glad that I bought his freshly rebuilt HS engine and at a reasonable price!

I think that was Mick Dickinson - see also the posting in 'Suppliers'
viewtopic.php?t=12856

(Maybe someone will have an update.)

SG

Maybe we should go the way Velocette did. Revert to the Cast iron barrel and steel push rod cover tubes for cooling and lightness and have the fifth stud for the 500's incorporated in a new pattern. If I was a bit younger I'd probably do it. The pattern is not that complicated. The Later 500cc twin did that so there's precident. Alloy barrels are a whole lot of angst sometimes. Nev