1950 Ariel red hunter 497cc VH piston rings

Bikes or not. Whatever
DaveCorey
Posts: 17
Joined: Thu Sep 26, 2019 6:11 pm
Contact:

1950 Ariel red hunter 497cc VH piston rings

Postby DaveCorey » Thu Dec 26, 2019 4:23 pm

Happy Christmas to all members and best wishes for 2020!! I now have the engine in pieces and need a ring set: the piston is reusable but I wish to change the rings and looking at the listings by Draganfly I am not sure if they have what I need. My piston is stamped inside 5627 HEPLEX which I assume is a Hepolite piston and it is .040 over the standard 81.8 MM., the depth of the grooves are aprox. .200" of an inch and the rings are .145" in depth. There is nothing on the D n' Fly site that matches that. Can anyone shed some light on this piston and where I can get a ring set. Warm regards, Dave.

User avatar
dave.owen
Holder of a Golden Anorak
Holder of a Golden Anorak
Posts: 1419
Joined: Wed Mar 23, 2011 10:05 pm
Location: swindon
Contact:

Re: 1950 Ariel red hunter 497cc VH piston rings

Postby dave.owen » Thu Dec 26, 2019 7:28 pm

Try cox and Turner, in Somerset, they supply rings.

Dave
AOMCC Treasurer

pete.collings
Holder of a Waxed Cotton Anorak
Holder of a Waxed Cotton Anorak
Posts: 571
Joined: Fri Feb 18, 2011 10:26 am
Location: Cardiff
Contact:

Re: 1950 Ariel red hunter 497cc VH piston rings

Postby pete.collings » Thu Dec 26, 2019 8:28 pm

There were two depths of compression rings for a VH, the low(er) compression pistons have depths of 0.115" and the higher compression pistons have a depth of 0.130", the other dimensions are the same (1/16" thickness and nominal oversize).
I think your piston may be a 7.5:1 compression ratio (is it flat topped with small valve cutaways?), my Hepolite ring catalogue only gives Hepolite piston numbers, but I can supply the Hepolite ring reference numbers if needed.
You should avoid putting the deeper rings in the low compression pistons, especially if there is carbon build up in the lands, as the rings could seize.

nevhunter
Holder of a Golden Anorak
Holder of a Golden Anorak
Posts: 4065
Joined: Tue May 10, 2011 9:42 am
Location: Victoria.. Australia.
Contact:

Re: 1950 Ariel red hunter 497cc VH piston rings

Postby nevhunter » Thu Dec 26, 2019 10:55 pm

You often don't know whether the piston was originally semi finished or a larg(er) size reground. Always check the rings don't bottom in the grooves . When a straight edge is held in line with the skirt you should have at least .005" clearance at the bottom of the grooves or you risk breaking rings. For the same reason all carbon should be removed from the base of the ring grooves .Particularly the the top groove should be checked for wear of the top and lower faces of the ring groove. If it's excessive remachine the groove to fit a (slightly) a wider ring

DaveCorey
Posts: 17
Joined: Thu Sep 26, 2019 6:11 pm
Contact:

Re: 1950 Ariel red hunter 497cc VH piston rings

Postby DaveCorey » Fri Dec 27, 2019 1:31 am

Thanks for the quick response, the piston is the 7.5: 1 comp. ratio and with a groove depth of .200" the rings have all kinds of space as the rings i saw on Draganfly were .115 deep and some less. It's the piston #5627 Heplex that I can't find anywhere to be sure I get the correct ring set. The 2 compression rings are 1/16" thick and the 3 piece oil ring groove width is 3/16"and all are .145" deep so with .005" total clearance between piston and cylinder there is still more than .050" of clearance in the groove bottom. By measurement the piston is exactly .040"oversize. I will check with Drags when they reopen in January to see if their ring set is compatible. I have never seen a piston with grooves that deep.

nevhunter
Holder of a Golden Anorak
Holder of a Golden Anorak
Posts: 4065
Joined: Tue May 10, 2011 9:42 am
Location: Victoria.. Australia.
Contact:

Re: 1950 Ariel red hunter 497cc VH piston rings

Postby nevhunter » Fri Dec 27, 2019 6:45 am

That can happen with semi finished pistons. but not to the extent that you have and I doubt Hepolite did semi finished ones. While it's not considered a good thing to have a lot of extra ring land depth, for ordinary running I doubt you will have a problem. Nev

User avatar
Bob.Murphy
Holder of a Silver Anorak
Holder of a Silver Anorak
Posts: 947
Joined: Thu Nov 29, 2012 10:32 pm
Location: Kirkliston, on the West side of Edinburgh.
Contact:

Re: 1950 Ariel red hunter 497cc VH piston rings

Postby Bob.Murphy » Fri Dec 27, 2019 10:54 am

You could try:

F W Thornton & Sons Ltd.,
Orleton Lane,
Wellington,
Telford,
Shropshire.
T: 01952 252892
E: enquiries@fwthornton.co.uk
W: www.fwthornton.co.uk

I found them to be very knowledgeable and helpful when looking for a standard Panther piston.

Bob.
My avatar shows the late Len Rich in 1970 with the bike I now have - a 1958 Ariel VH

DaveCorey
Posts: 17
Joined: Thu Sep 26, 2019 6:11 pm
Contact:

Re: 1950 Ariel red hunter 497cc VH piston rings

Postby DaveCorey » Sat Dec 28, 2019 3:19 pm

Thank you all for replies: I agree with Nev that even though the grooves are deeper than they should be it probably won't be a problem as my days of running full throttle are over. At 71 I still enjoy the thrill of flying down country roads but not as fast as when I was a young man. Also I will install a oil pump with better output so I am sure all will run well. Cheers!

User avatar
alan.moore
Holder of a Golden Anorak
Holder of a Golden Anorak
Posts: 1345
Joined: Sat Jul 19, 2014 1:29 pm
Location: Leicestershire UK
Contact:

Re: 1950 Ariel red hunter 497cc VH piston rings

Postby alan.moore » Sat Dec 28, 2019 3:22 pm

dave
Have a look at this old Ebay listing, it shows a 5627 and the original box?

https://picclick.co.uk/Ariel-500-Ohv-Pi ... 77157.html

and the 5627 is listed in the Drags piston PDF, in the VH section , 7th piston down, https://www.draganfly.co.uk/data/pdf/piston.pdf which you have probably already looked at.


Cheers
Alan
1939 VH Redhunter;1942 RN WNG;1951 Triumph 6T Thunderbird;1970 BSA B175 Bantam;1986 Yamaha SRX600 single
http://cloggymoore.wix.com/triumph-pre-unit-6t

User avatar
alan.moore
Holder of a Golden Anorak
Holder of a Golden Anorak
Posts: 1345
Joined: Sat Jul 19, 2014 1:29 pm
Location: Leicestershire UK
Contact:

Re: 1950 Ariel red hunter 497cc VH piston rings

Postby alan.moore » Sat Dec 28, 2019 3:54 pm

Dave
Just measured a 11497 Heplex, which the Drags list shows as having the same ring dimensions as the 5627 & 10503. Ring groove depth top two rings is .120, oil ring groove depth .153

Cheers
Alan
1939 VH Redhunter;1942 RN WNG;1951 Triumph 6T Thunderbird;1970 BSA B175 Bantam;1986 Yamaha SRX600 single
http://cloggymoore.wix.com/triumph-pre-unit-6t


Return to “Main Chat Forum”

Who is online

Users browsing this forum: No registered users and 8 guests