'81 GS450SX questions: Koni's? front air suspension? clutch springs?

[kymasabe]

I recently picked up (by recently, I mean about 2 months ago) a crusty old '81 gs450sx...says the vin plate. Alot was missing including the tail section, seat, seat frame, front fairing, and both fenders, as well as left side cover, battery strap and door, mirrors, directionals, and some other little odds and ends. We're slowly working in the bike, trying to resurrect it and I've found a few things that I have questions about.

First of all, this thing has Koni rear shocks. Did they come with Koni's?
Second, this has air suspension in front. Has air lines going to the fork caps. Again, is that factory?
Lastly, the clutch is very hard to pull. I pulled the left side cover that covers the sprocket, worm gear is clean and moves easily, cable moves well with the cover off. I'm guessing I have stiff clutch springs.

I'm beginning to wonder if this bike was raced? What do you think?

Anything else I should look for? I just removed the chain, was rusted and crappy, no removable master link, the chain was rivetted together. I've had lots of Jap bikes and I've never seen that from the factory before.

 

[Steve]

Several questions here, so I will just answer them in your quote.

I recently picked up (by recently, I mean about 2 months ago) a crusty old '81 gs450sx...says the vin plate. Alot was missing including the tail section, seat, seat frame, front fairing, and both fenders, as well as left side cover, battery strap and door, mirrors, directionals, and some other little odds and ends. We're slowly working in the bike, trying to resurrect it and I've found a few things that I have questions about.

First of all, this thing has Koni rear shocks. Did they come with Koni's?
No, they did not come from the factory with them, but they were a poplular upgrade, "back in the day".
Second, this has air suspension in front. Has air lines going to the fork caps. Again, is that factory?
Might have had air-assisted forks, but not sure if the external lines were stock. Today's popular upgrade is to replace the springs with ones that have proper rates (from Progressive or Sonic) and don't rely on air that can easily leak out.
Lastly, the clutch is very hard to pull. I pulled the left side cover that covers the sprocket, worm gear is clean and moves easily, cable moves well with the cover off. I'm guessing I have stiff clutch springs.
If everything else seems to be OK, yes, it's probably the springs. New STOCK springs would cure that. You should probably look into getting a new cable, too. Although it seems to operate easily with no load, the strain of pulling on the springs might have worn a groove in the liner, causing extra friction.

I'm beginning to wonder if this bike was raced? What do you think?
Not necessarily. Could have been a well-intentioned (but sadly mis-informed) "previous owner".

Anything else I should look for? I just removed the chain, was rusted and crappy, no removable master link, the chain was rivetted together. I've had lots of Jap bikes and I've never seen that from the factory before.
Yep, no master links from the Suzuki factory. You had to pull the swingarm or extract a pin. I think the intent was to get you to service the swingarm bearings every once in a while.

 

[SVSooke]

Since I bought your 450's Canadian brother the 81 GS400E back in the day I can answer the things Steve didn't know.The shocks look familiar?Yes I bought a set of Koni's for mine.
The forks did not come with air fittings in 81,those where added a year later though.
If it where raced there would be holes drilled in a few of the nuts and screws for safety wiring.I have one done on the bottom fork clamps.on my 85 750.

 

[Steve]

http://s573.photobucket.com/user/sersooke/media/IMG_0001_zpsc2517362.jpg.html
Since I bought your 450's Canadian brother the 81 GS400E back in the day I can answer the things Steve didn't know.

Thanks for the education, fine sir.

.

 

[kymasabe]

SV...regarding the racing...duh, I should have thought of that, the safety wire thing. 15 years and 100lbs ago, I used to roadrace 600cc sportbikes, (Honda CBR600F2's and F3's). Just about everything on my bike was safety wired, including the screw-on oil filter. I forgot all about the safety wire thing. And no, I haven't run into any nuts or bolts that have been drilled for safety wire.

 

[SVSooke]

You are welcome Steve,had a couple of GS400's and I really like them thus I have quite a bit of knowledge.Hoping I can find a GS400 for the next project but the 400cc bikes seem to have dried up around these parts.
While not a racer back when I had the bike in that picture I used to go to the local track Westwood (RIP) every motorcycle race day I could.That's why I knew what the drilled across the flats nut was from.It's a one off in my nut collection so I'm guessing it got "liberated" of a racer by a PO.

 

[850 Combat]

I loved those when they were new, especially the S. I'll bet they were great with 8 valve head Canadians got. I would love one now. That silver one looks great.