GS1000ST clutch plates Aust model

[Guest]

Hi Everyone,
I've been following the GSResources site for a few years now, don't think I've ever posted (?), so here goes.

In May of 2012 I purchased a very, very sad 1980 GS1000ST. I completed the restoration of this bike and finally got it on the road in Jan of this year 2015.

A little while ago I took the clutch apart, it has always seemed a bit heavy for me. (I also have a 1981 Suzuki 1100SZ Katana, wire-wheel model that is standard and this bike has a nice light clutch operation. By comparison another bike I have is a 1983 SD 1100 Kat that has a standard but quite heavy clutch. I do know that these bikes have different clutch internals as standard, plate thicknesses and numbers of etc. I've cured the SD by using a longer clutch release arm purchased from Webike Japan, this works a treat so the SD clutch is just fine now.)

Anyway I checked the GS1000S plate thicknesses, the 8 fibre plates were from 2.98 to 2.88mm. Wear limit is 2.4 so they have plenty left in them.

The metal driven plates are all 1.55mm, there were 7 of these in the stack I took out of the bike.

Clutch spring free length I measured as 38.30mm for all 6 springs.

Only trouble is that there is another doubled metal plate in the stack of plates that is not shown in any service manual I've seen. It looks like a factory item, it has a series of rivets holding the two plates together and it was placed between the last fibre plate and the clutch pressure plate. It looks just like one of the standard metal plates, just that there are 2 of these riveted together by 16 rivets. 8 Rivets face front and 8 face to back, they alternate direction as they go around the plate. The double plate is about 4.6mm thick. This additional thickness to the standard number of fibre and metal plates, i.e. 15 is no doubt the cause of why my clutch is not as light as I think it should be.

My question is, why does my GS have this 'extra' double plate and can I safely take it away and use the bike without damaging the bike?
Hopefully attached is a photo of the double metal plate so you can see what I'm talking about. Cheers, Rob.
GSclutch2.jpg

[blowerbike]

i have never seen the double steel on US models....
odd..

[Nessism]

i have never seen the double steel on US models....
odd..

What makes you think Felix is in the US? "...this works a treat..." Common expression from the UK boys.

No clue about that double plate as mentioned, it's not used in the US. I do know that a new clutch cable is a thing of beauty so make sure yours is fresh if you want the least lever effort possible. Also make sure you have the stock Suzuki springs. Common aftermarket springs are quite stiff for the most part so avoid them unless you are drag racing and need the extra clamp force.

[blowerbike]

lol

just letting him know i have never seen a double steel and where i'm from(that maybe UK may have been different or a UK after market may offer something like he has...lol
oh,
and more stack height equals a stronger clutch pull with all other things created equal....

[Felixthekat]

Thanks for your thoughts on this matter. I'm from Australia, Phillip Island. (where the MotoGP races in Oct every year.) I think the bike is an Aust delivered model. Details are as follows, frame GS1000-532541, engine GS1000-149837, built 5/80. It is red/white with the Mikuni BS34SS CV carbs.
Here is a recent photo of the bike...
Finished2 GS1000S.jpg
A bit more info, the bike has a brand new OEM clutch cable, standard Suzuki clutch springs. So not sure why it is heavier in operation than a SZ Katana. The double steel clutch plate I thought a bit odd and clearly part of this issue, but why is it there and how come it doesn't seem to appear in any manuals? A bit of a mystery so hoping someone has come across this before.
Cheers
Rob

[GregT]

I've seen the doubled plate on a couple of Kiwi 1000S motors. Maybe it is a local market variation, after all, we got "black pipe" production race specials...Also from what I've seen our S's here stayed with the big VM30's when the US went to CV carbs - though yours obviously differs...
Anyway, it's there to increase the clutch's torque capacity. If you want a light clutch, maybe another extended arm like your SD. If you're just road riding, you could probably get away with a single plate.
Oh, and from what I've seen the usual fitting position is at the back,not out at the front, shouldn't make much difference though.

[Kiwi Canuck]

Can't help you on the clutch issue, but just a comment on your bike.

I have that one listed in my GS1000S registry and it was owned by Rob N***ll, is that you or maybe a previous owner?

BTW are you going to the Classic Races next month?, should be a few GS1000S's there racing as well as on show.

[tatu]

I have never seen a double sided metal plate before that's very strange, also just to add there is nothing wrong with clutch on my 1000S but also the clutch on my 1000SZ is super light by comparison.

[Felixthekat]

Hi Kiwi,
Yes that is me, so therefore I have been on this forum before!
Yes most definitely I will be at the International Classic at the track. And again yes each year there are a few GS1000S racing. I remember from last year a yellow one. Lots of fun!!
Back to the clutch, this is interesting. Shows that Suzuki changes things and maybe doesn't get around to recording same in service manuals?

[Felixthekat]

Hi Greg,
As you say maybe it is a local market variation. Sorry I don't understand what you mean about the usual fitting position is at the back etc.
Always eager to learn a bit more.
Thanks again everyone for applying your combined skill and experiences. Perhaps I will just fit an extended clutch release arm as it works so well for the SD. Otherwise the bike works just fine. I took the GS1000S out today and mentioned the heavy clutch to one of the guys I have a Saturday morning coffee with, he said in comparison to one of his bikes (I think he was referring to his Harley when he tried the GS clutch) that in his opinion it was very light. Then again a Harley of which I have no experience.

[Felixthekat]

Just been in the garageGS Clutch Release1.jpg and compared the original GS1000S clutch release arm (on top in this photo) with the SD Kat one Ive just installed. Never actually measured them against each other but clearly the standard Katana arm is a bit longer, maybe 5mm than the standard GS arm. So this will help a bit. I am quite pleased!

Greg, Is this what you meant by the fitting pos'n, i.e. that the securing bolt should be coming from the opposite direction from what I show in this photo?

[GregT]

No , I meant the doubled plate is usually at the back of the clutch pack, first steel installed on the hub.
We bought almost 2 1/2 rough and incomplete GS1000 motors several years back as spares for the racebike. I'm pretty sure one of the clutches has the doubled plate. I've never looked at the engine numbers to see if any of them were "S" motors.
I have however found those plates on other S motors I have worked on here so it's not that rare.

[Thsel]

Hi, just checked out my GS 1000 ST clutch and has the same double plate, just as well I had a look too as it has lost a few of those rivets ,it has engine & frame numbers that are close as well. I don't know how yours has CV carbs tho, this is my second one of these bikes and both had VM carbs

[Thsel]

Like to know more about your registry , I have an ST I have just finished restoring and nearly ready to go riding.

[Kiwi Canuck]

Like to know more about your registry , I have an ST I have just finished restoring and nearly ready to go riding.

Hello Thsel, welcome to the forum, a great place to hang out for GS owners.

I have been maintaining the registry for the GS1000S model for the last 2-3 years.

I started the registry to try and figure out how many GS1000S's were made and approx. how many still exist.

With plenty of help from this forum I've managed to collect more than 100 VIN numbers and almost as many engine numbers over the 2 model years, (1979 & 1980)

My info is incomplete but I believe there were approx. 7,000 units sold for 1979 and about 5,000 for 1980 worldwide.

If you would send me your VIN and Engine numbers and the date of mfg and I'll add them to the registry.

Thank you.

David.