Engine differences between old and new GSX1100/GS1150?

[brufnus]

Hi folks!

After owning a GSX1100EF (known as GS1150 in the U.S.) for nearly 30 years, there's one question I've never found an answer to - wasn't much of an issue until recently, when I rebuilt the bike and installed earlier engines from bikes I bought in Switzerland.

It appears that the initial engines from 1984/85 has a performance of "only" 114 HP (maxing at 8,700 rpm), whereas the latter engines puts out 124 HP and maxes lower, namely at 8,500 rpm. I think the torque maxes lower as well on the latter engines.

I was thinking it could be the camshaft height, but according to my Haynes Workshop Manual, they all seem to have identical cam heights (no mentioning of any differences, anyway).

Does any of you guys know what causes the difference? Same bore and stroke, same carburettors, apparently same camshafts, etc... but still 10 HP less?

 

[hillsy]

The EF was 1135cc whilst the earlier engine was 1074. 2mm larger bore. 36mm carbs v 34mm.

 

[londonboards]

Hello and Welcome

My understanding is as follows:

Essentially all engines that look like this:



are 124 hp.

The previous generation found on the Es, ETs and EZs which look like this:

are of lower hp of 111.

This recent magazine article shows the progression:

That's the European story. I think you might be confusing your dates. As pic above, anything 1984-1985 would have been the EFE engine with 124 hp.

However, there may also have been regional variations in the US, such as models made specifically for California or Canada that had restrictions or modifications for environmental reasons, which may have reduced HP on the 1984-1985 EFE engines.

This is helpful:

http://www.suzukicycles.org/GSX-series/GSX1100E.shtml

and concurs with my analysis.

This isn't so helpful as I think the 1984 GSX1100 EF (known in the US as the GS1150 EF) is incorrectly listed as having 114 hp:

http://www.suzukicycles.org/1980-1989/1984a.shtml

Hope that's a start anyway.

 

[brufnus]

Thanks - I agree, there seems to be some wrong informations at suzukicycles (it's not the only error; it also claims the rear wheel is an 18", while it's a 17".
(If it's not, I've been mounting a too small rear tyre for nearly 30 years) c".) lol

It wasn't the dates I confused actually, I did mean the first 1135 engines from 1984. The above mentioned claim did confuse me, however. c".) But I've never seen any difference in engine components or seen any dealer or broker requesting an engine number in order to deliver the correct item. The German versions had a limit, too, 100 hp - but this was achieved by installing drossle plates in the intake rather than using, e.g., different cam shafts etc.

So... now I feel much better. It seems the engines I have from Switzerland (four by now), all should have 124 hp and 10,7 kgm torque. c",)

Thanks for your reply!

 

[jimb12]

I know a guy that bought a 1986 GS1150E (USA) and it was from California. He said that when he got it, there was some kind of emissions crap on it. So perhaps there were regional issues.

 

[londonboards]

So... now I feel much better. It seems the engines I have from Switzerland (four by now), all should have 124 hp and 10,7 kgm torque. c",)

This begs some questions which curiosity prompts me to ask:

1. Why do you need 4 engines. I have made do with only 3.
2. Have they re-started manufacture in Switzerland?
3. Can you put me in touch with your supplier. I would quite like a few more.

Greetings

 

[sharpy]

Hi folks!
I was thinking it could be the camshaft height, but according to my Haynes Workshop Manual, they all seem to have identical cam heights (no mentioning of any differences, anyway).

Download a Genuine Workshop manual/s from basscliff website http://members.dslextreme.com/users/bikecliff/ and cross reference you parts numbers in Mr Cycles http://www.mrcycles.com/oemparts/c/suzuki_motorcycle/parts or similar sites. That be a way better option than a Haynes manual.

 

[rapidray]

This begs some questions which curiosity prompts me to ask:

1. Why do you need 4 engines. I have made do with only 3.
2. Have they re-started manufacture in Switzerland?
3. Can you put me in touch with your supplier. I would quite like a few more.

Greetings

I have 22 of those engines, how many do you want? I also have just cases & heads too! Want some of those?
Ray.

 

[londonboards]

Ray

So do you have an eBay shop or website?

I figure this is your livelihood and I'm always in the market. Just bought a nice crank from the US and a complete US EFE from an importer.

I'd love a rebuilt Ray head with some porting, a good set of street cams and slotted sprockets.

Greetings