pistons

[Ultim8pc]

After I have pretty much finished my z900 re-commissioning it runs like a bag of crap.
No2 exhaust not getting as warm as the rest.
Anyway, I knew the compression was a tad on the low side (but not out of spec) and as the timing, plugs, coils and valve clearances have been done and carbs rebuilt, I thought I'd do a compression loss test:
1, 3 & 4 all good, No2 with high amount of loss.
I have whipped off the head and can see that the bores have been previously honed and you can still see assorted rust marks on the bores that this was an attempt to solve. No2 is particularly bad.
I've yet to do a valve leak test, but if that that doesn't show up anything then it looks like I'm going to be needing a re-bore and new pistons...
Anyone recommend any of the the non-OEM piston options such as IMD?
Also, any recommendations for re-boring in the North of England?
Thanks in advance.

[DavidZ1R]

Engine technics by me very good, done mine, and does all z powers bikes. Westhoughton, Will Barber uses them too for his turbo jobs.

[Blackseven]

I used Engine Tekniks earlier this year, amongst other things for a rebore on by Z1000. Very good service, decent prices and nice people too. I supplied 0.5mm IMD pistons and Paul at Engine Tekniks was complimentary about them.

Rob