A Dominator curiosity? Wire-wound pistons

Yes, got em in my 99, std bore & the bike had just a tad over 8000 miles on it when I got it so have always assumed them to be original fitment, anyone know for sure on way or the other?

Regards, Tim

Wire wound pistons first appeared on the Norton big twins in 1956. They came from an AMC suggestion as a means of cutting down engine noise, especiallywhen started from cold. They were designed to run with much finer clearances butbeing more expensive to produce, soon got the 'heave-ho' when the next generation of 'low-expansion' alloy pistons arrived on the scene.

Hi all,

I have amongst my bits and pieces a pair of wire wound pistons for a Dommie Model 7 or early 88, I would presume that these are after-market rather than OEM, the odd thing though is that they are for STD bores, now I've heard a bit about-wire wound pistons in AMC singles and it was my belief that the advantage was reduced expansion, therefore tighter bore clearance, so unless someone was going to get their bike sleeved back to STD bore, what good would they be, they would be even more clattery than ordinary Hepolites? Unless they are already 3/4 thou oversize to fit a standard bore, but closer?If the box is anything to go by, they are early 1950s.

Has anyone heard of these?

Cheers,

Niall

Hello The Original Pistons were made by brico heavy industry other wise know as BHB pistons and they were copied by

Hepolite of Bradford they were then copied by GPM pistons and JP pistons so we have now 3 copies of the original pistons made By BHB its was Hepoite that made over size piston to plus 60 and this was the biggest mistake , this in turn started off the splitting of the top spigot and sometime the splitting of the barrel as well the original pistons only did over sizes to plus 30 and they said at the time that any more out of the barrel would end up with treble with the spigots and it seem they were right. I have a long paper document on piston tpyes and piston ring types it makes for interesting reading, Yours Anna J