Hepolite pistons and camshafts

[mrshells]

Standard pistons for a 52 Startwin are 11288 at 7.25 CR
Ive heard a rumour that 11603 8.5 cr will fit
also bike has a 356 cam is there a quicker profile standard cam that will fit ?

[muskrat]

G'day mrshells, 357 is the sports cam that delivers more up top, have srrn them new on flebay for about 80 pounds. Pistons should fit if their for an A10.
Cheers

[MG]

I think you will need stronger valve springs for the 67-357 cam.
The pistons are A7 Shooting Star I suppose? Whats the bore and stroke dimensions of the 52 StarTwin? I think the SS is shorter stroke and larger bore, so I don't really believe they will fit.

[mrshells]

shooting star and star twin are the same bore and stroke 72.9x66 mm shooting star has higher compression
I have been told they will fit but just wanted a 2nd opinion

[MG]

you are right, it's just been the first star twins that had the different bore and stroke size.

So the A7 SS pistons should definitely work, and pistons for the std A7 should be fine too, although with lower CR. I made good experiences with JP Pistons from Australia for the SS. You could also contact Roger Shirman from Cake Street classics (just google). He sells forged Wisecos for A7 and A10 which are absolutely brilliant. But I can't remember what CR the A7 ones were...

[mrshells]

cant get hold of cake classics
but been on wiseco web site and they dont list anything  ???? ???? ????

[MG]

Company:    Cake Street Classics (A7/10 Parts and Rebuilding)
Address:   Cake Street, Barnyard Screen
               Laxfield
               Woodbridge
               Suffolk
               IP13 8EW

Contact:   Roger Shirman

Telephone:   01986 798504


The pistons are specially made for CSC, I also couldn't find them elsewhere. roger was very helpful, give him a phone call, I think he's not so much into computers and email...

[mrshells]

are you sure they were the real deal ?
I dont mean to insult anyone but wiseco are a bloody big company to make pistons for a little shop in the UK and not market them,themselves
In the mean time I got hold of some +40 good used pistons and put new rings and pins in them ,the barrels are in for rebore now
the crank is having a grind and the heads having a little skim !
couple of weeks and shell be running like new again 

[MG]

They definitely are Wisecos. They came in the origianl box with factory documents and fitting instructions (and Wiseco decals ). And having seen several forged Wiseco pistons before and knowing how they should look like, I dare to state that they are originals.
Wiseco also produces pistons made to specific orders, you just have to order a batch that is large enough. They also make pistons for Goldstars and Bonnevilles, sold by other smaller suppliers in the UK. I suppose it is not such a huge problem, if they have a suitable forging blank that can be machined to size.

[mrshells]

Ill have to keep trying him then
thanks

[mrshells]

Got hold of cake St he only has A10 pistons

[MG]

Sorry to hear that, I thought CSC would have Wisecos for the A7 too, my memory has obviously fooled me here. I apologize for having mislead you.

But you might want to try JP in Down Under (http://www.jp.com.au/JPPistons.html).
They have listed A7 pistons with a CR of 6.6 on their website. I'm using JPs in the A7SS. Mine had a CR of 8.25 or 8.5, I can't remember exactly. Just write them an email, I think they haven't listed everything on the site.
They are cast and not forged like the Wisecos, but therefore they are a bit cheaper and look reasonably well manufactured. They work pretty well in the SS, I fitted them with a clearance of 4 thou. I think JP stated 3 thou if my memory serves me right, but I tried to stay on the safe side here.

Cheer, Markus

[bsa-bill]

Lyford Classics have them listed in their catalogue std,+20,+40 and +60 might be worth a call if you haven't already
tel 01773 768900
or http://lyford-bsa.co.uk/home.html

All the best - Bill

[Josh Cox]

mrshells,

I had trouble finding Hepolites for my A10, ended up ordering them from Draganfly, they sent me JP's, which I am thus far very happy with, as I am already in Australia, that makes my pistons very well travelled.

[alanp]

Thanks to this topic, I now know what pistons I have. I wondered what 'JP 0624' on the piston crowns meant. Australian, 9:1.
Love this forum!
Alan