85 GS 700 to 1100

[richardhaggarty]

I have done a lot of work on my GS 700, but I would like to do a performance rebuild on the valve train. I can only seem to find parts for the 1100 and 1150 engines.

Am I just not looking in the right places?

Is swapping up to an 1100 an option?

[Hap Call]

Richard, it's my understanding that the GS700 was a totally new generation of the 16V GS750 that started in 1980. Your engine is smaller and lighter than the original 16V 750. Because of that, it is difficult to swap 700 and the 1100 engine and no parts are interchangeable.

Hap

[Billy Ricks]

You can use 1100 and 1150 based cams and spring sets. The cam gears are different so you would have to slot your own. A 750 crank and rods with your pistons will bump up compression for a little more punch.

[richardhaggarty]

Thanks Billy; I was hoping I could use the 1100 cam and springs in my 700.

With a newly rebuilt head the 750 crank and rods might be a nice addition. There is a 1983 being parted out in the classifieds; is that a suitable donor?

Any idea on how difficult it would be to cut a set of cam gears? Would I have to fab them up from scratch of can I modify my stock 700 gears?

Thanks everyone for your help

[Billy Ricks]

Thanks Billy; I was hoping I could use the 1100 cam and springs in my 700.

With a newly rebuilt head the 750 crank and rods might be a nice addition. There is a 1983 being parted out in the classifieds; is that a suitable donor?

Any idea on how difficult it would be to cut a set of cam gears? Would I have to fab them up from sctrach of can I modif my stock 700 gears?

Thanks everyone for your help

The '83 and up 750 crank and rods is what you would want. You would have to either slot your own gears or have them slotted. The holes only need to be elongated perhaps 1/8" in both directions to give you the adjustment range you need. When you look for cams get something intended for 750s up. The stock cam profiles are pretty much the same between models. I'd look for some aftermarket drop-ins or hot street cams.

[Hap Call]

Billy, the third generation GS700/750 engine shares cam support and lobe spacing with the 1100/1150? I thought the 700/750 was much more narrow than the 1100/1150. Have I got that right?

Hap

[richardhaggarty]

I called GS zone (http://www.gszone.biz/index.html) the division of APE that specializes in GS engine performance.

They said thier computer was telling them that the vavles, valve seats and valveguides were compatible. They were not sure about the valve springs or the cam shafts.

I check that against microfiche part numbers from JT Motorsports, (http://www.crotchrocket.com/fiche_select.asp) a stock replacement part supplier. The valve springs and valve spring retainers share the same part numbers.

However, the valves themselves have different parts numbers, but I think that is because suzuki is currently updating part numbers; the GS700 has the valve part numbers listed in the new format, the GS1150 does not.

The jury is still out on the cam shafts.

Models used for comparison:
1985 GS700E
1985 GS1150

[richardhaggarty]

I just bought a crankshaft and rods from a 1982 GS750E on eBAY.

The plan for the engine pull:

Fix the second gear slip with rebuilt trannsmission
Rebuilt GS750 bottom end for increased compression
Modify harness for DYNA 2000 ignition, driving lights and LED signals

I would like to do the head also, but I think that may be too much to get done in time for the spring, we'll see. A complete rebuild would be nice; I could get the engine cases powder coated.

[Billy Ricks]

Hap,
The last generation 750's use the same aftermarket cams as the 1100/1150 16 valve engines. You can't run the really high lift drag cams but the rest will fit fine. The 700 exhaust cam was supposed to have been a hot item for the 750's. The 700/750 valve covers will fit the 1150 as well.

[oldschoolGS]

I would check the '82 stuff, I do not know if the bottom end was common between '82 and '83. The bike went thru a major change in '83.

GS1100/1150 cams, springs, and cam chain/tensioner are the same.

The best combo I have found for stock 747cc displacement are:

-750 crank and rods
-700 pistons (they are domed to make up the compression loss by destroking and will give 10.25-1 with 750 crank and rods)
-.325-.330 lift cams and HD springs
-GSXR CV flatslide carbs and pods (1986,87 GSXR1100 34mm are best)- RS34 flatslides are nice but cost $.
-High output ignition

This makes for a very nice motor. By going higher compression or with higher lift cams you will start to loose streetability.

Good Luck, Ed
1983 GS750ED
2005 GSF1200SZ

[Billy Ricks]

I just bought a crankshaft and rods from a 1982 GS750E on eBAY.

The plan for the engine pull:

Fix the second gear slip with rebuilt trannsmission
Rebuilt GS750 bottom end for increased compression
Modify harness for DYNA 2000 ignition, driving lights and LED signals

I would like to do the head also, but I think that may be too much to get done in time for the spring, we'll see. A complete rebuild would be nice; I could get the engine cases powder coated.

I don't think the '82 crank will work either. Suzuki made big changes to the bottom end in '83. You can compare them but I think it's going to be different. The changes were needed to make room for the Full-Floater.