Gs750 big bore kit

[Nessism]

the big bore kit for gs750 are from a stock 65mm to 69mm meaning its 2mm oversize not 1mm which means l will only have approx 1.9 mm left on the liners

That's a 4mm over bore, not 2mm.

[tkent02]

Why not just us an 850 barrel and bore it over to use the stock 1000 pistons?

843cc's become 868cc's Or, you could use somebody's 70.5 pistons and make it 880cc's. ($85.00 with shipping for the 70.5 pistons/rings/pins)

Daniel

I like that idea, but don't the 1000 pistons use fatter wrist pins than the 750/850? Too lazy to go out into the garage and look.

[TeamDar]

GS1000= 18mm wrist pins
GS750/850= 16mm wrist pins

[david fava]

you are correct the wiseco big bore kit is 4mm oversize (65mm to 69mm) but you actually only bore 2mm (radius) meaning you have actually made the bore 4 mm oversize.

getting back to the gs 850 barrels.you could get genuine 1mm oversize pistons and this would bring up the ccs to approx 900cc.the problem is they are expensive and and hard to get. depending on which suzuki dealer you deal with some have the rings but not the pistons and vise versa.

does anybody know of a suzuki dealer in america that deals with old stock genuine parts.l live in australia and we have a couple of dealers like that but l have been un succesful

[7981GS]

GS1000= 18mm wrist pins
GS750/850= 16mm wrist pins

I stand corrected.
I just measured them myself.
You would have to ream the rod ends to 18mm for them to work.

Daniel

[TeamDar]

you are correct the wiseco big bore kit is 4mm oversize (65mm to 69mm) but you actually only bore 2mm (radius) meaning you have actually made the bore 4 mm oversize.

getting back to the gs 850 barrels.you could get genuine 1mm oversize pistons and this would bring up the ccs to approx 900cc.the problem is they are expensive and and hard to get. depending on which suzuki dealer you deal with some have the rings but not the pistons and vise versa.

does anybody know of a suzuki dealer in america that deals with old stock genuine parts.l live in australia and we have a couple of dealers like that but l have been un succesful

70mm= 870cc
71mm= 893cc
72mm= 918cc
MTC used to sell 70mm & 72mm pistons for GS750 8-valve motors. The 72mm required re-sleeving.

[Big Jay]

You are measuring the spigot area of the sleeve ( the bottom), which is smaller that the sleeve O.D. in the block. You will be OK