Katana Owners Club U.K.

Hi, I am new to the group.
I have just bought a second 1100 Katana and find that the heads between the two bikes are different. This can be seen on the bolt pattern of the cam covers.
Were there different heads on different years or is the difference GSX and Katana?
Please can you help with this as well as any other differences.

Can't recall exactly when but there is an early & late style cam cover......

The GSX1100SZ had 20 bolts (holes) cam covers. The GSX1100SD (and I guess onwards) has 24 bolts (holes). On some pattern gaskets the 4 holes that are more or less next to the side covers are not fully enclosed so you might count 4 less (on both) if looking online at images. I have hi-lighted in yellow the image below the ones I mean (this is a SZ gasket).
The SD gasket has the extra 4 bolts end side of the Cam Chain tunnel, I guess cause it leaked there on the SZ(?).
Not wanting to pay Suzuki OEM prices I just bought some Vesrah Cam Cover gaskets from Poland as that was the best price I could find as they gave free postage over €65 (I got some other stuff as well). There's a post I think in the Technical section with part numbers (Vesrah SZ = VV-3006, SD = VV-3020).

Are you after differences on the whole bike or just the engine? I should hopefully be posting the Parts list soon which has pages for SZ and SD within it.

UB

Later ones have extra bolts on cam cover....as with all GS models to be honest.
SZ 1981-2 20 bolts .....SD 83-84 24 bolts. Engine wise they are the same.
Frame wise for rest hangers are different as are the wheels. And colour schemes.

and the later engines are black instead of silver and are generally a U702 engine number as opposed to a GS110X engine number on UK models. The later motors are a little stronger but were soon replaced by the 1135 efe engines

You may find different genny diameters on different gsx engines.

Oh, and welcome here.

not specific to the kat, the gsx1100et had the engine first and the 20 bolt cam cover was discovered to be prone to leaking round the chain tunnel, so it was uprated to 24 bolt on both the et and the kat and other gsx variants that used this engine, some sz models also had the 24 bolt cover depending on when they were built in the production run.

Thanks for all the replies...can I get from this that the SZ was the early Kat and the SD was the later?If so then I think I am happy.
The 1981 has 20 bolts and the 1984 has 24. I have a collection of 1970-80s Jap superbikes as investments so they have to be correct.

Not necessarily an SD engine if it has the 24 bolt rocker cover, my 1982 SZ (which I have owned since 1984) has a silver engine but it has always had the later pattern head fitted.

It has the later pattern generator but the earlier SZ style clutch basket , some changes were made early on in the SZ production run and others just prior to the SD model being released.

SD also had the plastic rather than fibreglass main fairing the the rear footrest hangars were different