Need advise

[suzuki]

Hello folks,
I'm a new member. I live in Cuba and i have a 1983 Suzuki GS 750 ES.
It's the only one of it's kind in the island. No parts here though.
I'm planing to add more power to the bike by putting bigger pistons and rings. Preferible form a bigger bike, suzuki 1000 cc for example.
I'd like to know if any one had tried this before and what arethe best pistons to use on my 1983 suzuki 750 to make it around 850 cc.
I'll send a picture of the bike later.
Thanks in advance.
Daryel

[49er]

Daryel
Welcome to the GSR.
Your 750 should have the same case dimensions as my 850. The strokes are identical with the piston sizes 65mm and 69mm respectively.
Your best move may be to fit an 850 engine to your bike. Or, you could buy a set of 850 cylinders, pistons and cylinder head, off ebay. You may even get these parts off the GSR.
If you decide to fit 850 pistons to your 750, you would need to re-sleeve the cylinders as your present ones would be too thin after a re-bore of 4mm. I'm not sure how your head chamber size and inlet diameters compare to the 850's though.
Hope this helps.
Cheers
Ian

[Hap Call]

Welcome to the GS Resources!!


The '83 GS750 was a major redesign that shares nothing with any of the other GS engines. It's a compact plain bearing 16-valve motor while the 850 is an 8 valve roller bearing motor so nothing between the engines will interchange, not even the mounting points. Also the 750 produced more HP than the 850.

The GS1100 that was produced at that time is a much larger motor as far as outer dimensions go and would be very tough to shove into the GS750E frame. It might be done but I'm not sure what would happen to such things as access to the valves for adjustments.

Even here in the US we have problems getting performance parts for the GS750. Most folks just go with a GS 1100E for which many, many performance parts are available.



Hap

[Dink]

1100 (16 valve) block and pistons will fit.

Dink

[Hap Call]

1100 (16 valve) block and pistons will fit.

Dink

Dink, if I'm not mistaken, he would have to do something about the cylinder height or get a stroked crankshaft, if one is available. The 750 has a shorter stroke (I believe 13 mm shorter) and would have extremely low compression with the stock 1100 cylinders. Also, the upper case would have to be machined to fit the lower cylinder sleaves.

Even more important, the engine cases on the 83 and later GS750 had nothing in common with the GS1100 cases...83 was the first year of the third generation engine for the GS750.


Hap

[49er]

Daryel
My apologies for the mis-information. I mistook your 83 GSX 750ES for a 82 GS 750EZ. The EZ is listed as a 2 valve motor on the www.motorcyclespecs.co.za web page under suzuki models. This info may be incorrect as well because they list it as having 4 x VM26SS carbs. I believe that all GS models from 1980 onwards were fitted with CV carbs.
Merry Xmas to you and your family.
Ian