Bore kit

[ohgoodtimes]

Does anyone know where i could find one for my 83 750e? Also is it more practical (for cost, effort, etc) than doing the swap for the 700 pistons cams and so on?

[Junkie]

Effort will be basically the same either way. No clue about cost or effectiveness, it's gonna depend a lot on what compression ratio you go with and other stuff.

[QuaiChangKane]

Timely question.


I don't know of any aftermarket big-bore kit for our bikes, and the 700 pistons will gain you nothing but a bit of extra compression.


I've heard that cams from the 1100 can be used for a greater power increase than the 700 cams, but can't remember if it's the 1100E/ES cams or the 1150 cams. Can someone shed some light?



I do seem to believe that someone made an 850 kit for the '83-up 750 at some point, but I could be mistaken.

-Q!

[Dizzixx]

Direct from wiseco

GS750 1980-84 (4-Valve)

Kit includes: (4) Pistons, Ring Sets, Piston Pins, Retainer Clips, and (1) CFM20 Head Gasket

816cc

2.756" or 70.00mm K816 10.25:1 Cylinder boring only - 1983 GS750ED & GS750ESD must use modifi ed OEM Head Gasket
3mm oversize $577.33 Piston: 4188M07000 $135.71 Rings: 2756XC Piston Pins: S555 Retainer Clips: CW18

Stroke - 53mm CFM20 Head Gasket: W4937 $52.36 Optional Base Gasket: W6064 $14.04


I have their 844 kit for the 2 valve head and I am way wayyyy happy with it. I also have a built up B12 but I like the ol 750 better Its a much more pleasant ride but the power is there when I want it. PULLS VERY HARD all way to redline and beyond.

[salty_monk]

I would think some added compression would make a sizeable difference on these engines...

Dan

[ohgoodtimes]

Hey dizzi are you using the stock cams or did you opt for aftermarket parts? I still like the 700 idea, i just have to price everything out.

[Junkie]

Direct from wiseco

GS750 1980-84 (4-Valve)

Kit includes: (4) Pistons, Ring Sets, Piston Pins, Retainer Clips, and (1) CFM20 Head Gasket

816cc

2.756" or 70.00mm K816 10.25:1 Cylinder boring only - 1983 GS750ED & GS750ESD must use modifi ed OEM Head Gasket
3mm oversize $577.33 Piston: 4188M07000 $135.71 Rings: 2756XC Piston Pins: S555 Retainer Clips: CW18

Stroke - 53mm CFM20 Head Gasket: W4937 $52.36 Optional Base Gasket: W6064 $14.04


I have their 844 kit for the 2 valve head and I am way wayyyy happy with it. I also have a built up B12 but I like the ol 750 better Its a much more pleasant ride but the power is there when I want it. PULLS VERY HARD all way to redline and beyond.

sounds to me like that's for the earlier 4v... do the pistons interchange?

[Griffin]

The bores on the first generation four valve GS750 ('80-'82) and second gen four valvers ('83-'86) are the same, so the overbore kits are the same. Wiseco does say on their site that if you use the kit in a GS700, there is a modification that has to be made (a spacer I think) to allow added clearance below the valves due to different piston dome shape.

I may be doing this to my 700ES in the next year or two due to compression has fallen into the 130ish range on my bike. Still not bad, considering it has 61,000 miles on it.

[Dizzixx]

Yeah I have stock cams. As well as stock carbs. There is still a very noticable difference.