.080. overbore .

[Torontonian]

I've ordered in .060 overbore on the advice by my machinist , from J.S. , forged .
I've heard at the Supershow this Wknd . that my final is .080 . oversize that is available , but who would supply that , not from Andover or J.S.
Thanks .

 

[Fast Eddie]

I've ordered in .060 overbore on the advice by my machinist , from J.S. , forged .
I've heard at the Supershow this Wknd . that my final is .080 . oversize that is available , but who would supply that , not from Andover or J.S.
Thanks .

Pretty sure JS could supply them.

 

[Torontonian]

Pretty sure JS could supply them.

Not that I'm aware . His site shows 060 . max. , ordered in . Just thinking about our limits and the future ...

 

[Fast Eddie]

Not that I'm aware . His site shows 060 . max. , ordered in . Just thinking about our limits and the future ...

He can make individual custom one-offs.

 

[Torontonian]

He can make individual custom one-offs.

Anything out there already made ?

 

[Fast Eddie]

Anything out there already made ?

No idea. But someone will surely know …

 

[marinatlas]

750 or 850 ?

 

[marshg246]

Anything out there already made ?

Doubtful. In theory, 750 max over is .040 and 850 is .020 (according to the workshop 065146 and the MK2 version)

Hepolite has .060 for 750 and .040 for 850 but no bigger. You already know what JS has.

Of course, you can have them sleeved or buy a used set that fits in what's available or even a new set from AN.

 

[milfordite]

Just curious, are you boring from normal wear, or more performance? Just wondering because my 850 is on .020" over at 70K miles and counting.

 

[phippsy]

Hepolite show +80 for 750 , can’t find 850

 

[marshg246]

Hepolite show +80 for 750 , can’t find 850

Where? AFAIK, only Wassell has Hepolite and they do not show +.080.

 

[jseng1]

I have 79mm medium compression pistons for Carrillo long rods in stock. I can special order them for stock rods.

 

[dobba99]

Doubtful. In theory, 750 max over is .040 and 850 is .020 (according to the workshop 065146 and the MK2 version)

Hepolite has .060 for 750 and .040 for 850 but no bigger. You already know what JS has.

Of course, you can have them sleeved or buy a used set that fits in what's available or even a new set from AN.

Hepolite do .060 see here overhttps://www.rgmnorton.co.uk/buy/new-hepolite-850-pistons-60-complete-pairs_187.htm
Hepolite also list .080 over, hepolite part no WW97335P although finding a dealer who has them in stock is another matter....

 

[L.A.B.]

Where? AFAIK, only Wassell has Hepolite and they do not show +.080.

Norvil lists +.080 for 750, 1914580 halfway down the page. I assume they're Hepolite.

Norvil Motorcycles - Cylinder Barrel, Pistons & Fittings

 

[phippsy]

Where? AFAIK, only Wassell has Hepolite and they do not show +.080.

I did a search and a few companies came up selling Hepolite +80 not companies I have heard of

 

[marshg246]

I did a search and a few companies came up selling Hepolite +80 not companies I have heard of

Strange. AFAIK, Wassell owns the Hepolite name now. I stock every size of Hepolite Wassell sells. Of course, the pistons are actually JCC so who knows? I'll ask the owner.

 

[Torontonian]

Just curious, are you boring from normal wear, or more performance? Just wondering because my 850 is on .020" over at 70K miles and counting.

Wear . 850 pistons and bore were worn out at .040 . Gord Bush Performance called to say I need to order in .060 pistons to them for the new rebore . Jim has ordered forged pistons in for the springtime , as I will be exploring west Africa with my wife .

 

[MichaelB]

I have 79mm medium compression pistons for Carrillo long rods in stock. I can special order them for stock rods.

Pretty sure 79mm is what KDreer ran in his VR880 builds..

 

[jseng1]

.080" is limit for 850s unless you resleeve. .040" is the practical limit for 750s without through bolts because they get thin and can crack - some .060" over 750s will fail unless you have through bolts.