Suzuki GSX1100 Katana

There can be no doubt that the Suzuki GSX1100S Katana was a timeless and iconic motorcycle of the early eighties, which in original condition is an appreciating investment. Values today start at around $4000 for a usable example and up over $10,000 for one in mint condition. In this Hindsight we look back at the Kat and examine the pros and cons of ownership.

HISTORY
A true Superbike, a 1074cc four cylinder DOHC air cooled engine making a claimed 108-110 horsepower at 8,500rpm and 9.8kgm of torque at 6,500rpm, housed in a tubular steel frame, suspended by four position preload adjustable forks, rebound and preload adjustable twin shocks and rolling on skinny 3.50x19/4.50X17 wheels.

The first all silver cast-wheeled Katana arrived in Australia in 1981 as the GSX1100SZ. At about the same time the 1000SZ also arrived, but in very limited numbers. Essentially the 1000 was a homologation special. At the time Superbike racing was capacity limited to 1000cc and so, Suzuki, keen to gain race cred for the new machine, obliged with the 1000S, complete with forged pistons, welded crank, slide type carburettors instead of CV and 18" wire wheels, allowing the use of more durable racing tyres. Mid way through 1981 another model arrived which was the SXZ. Essentially used as a racer, the SXZ was still an 1100 but featured an 18" rear wheel as well. It also featured a smaller rotor assembly that as a result had less flywheel effect when the throttle was opened and shut suddenly causing the rotor to spin on the shaft.

In 1982 the SD model Kat received subtle rather than drastic changes. Most obviously there was the black-painted engine that allegedly made more power and torque, but didn't. The chassis no longer had engine mount holes through the down tubes and the rocker box seal changed from gasket to O ring. Oh yeah - and the clutch gained extra plates. Rear brake lever was alloy as were the metal inserts in the footrests. And so the Kat remained largely unchanged until 1984 when it received a makeover as the SE that included new alloy wheels, and a black/silver or maroon/silver paint scheme, plus a heavier duty clutch. The last new Katana in Australia was sold from Mick Hone's in January 1985.

ON THE ROAD
Starting with the engine. The 1074cc Twin Swirl Combustion Chamber (TSCC) four cylinder has been a solid golden goose for Suzuki, enjoying an enviable reputation for durability and performance. And it delivers. Even today the Kat is no slouch, still just as happy to blaze away from the lights or a drag strip. That's not to say that the thing can't be docile because it can. The Kat seat sits 775mm off the ground and the engine makes the kind of torque that lets you idle down to low speeds without really troubling the five speed transmission unduly and still access the fire power.

As for handling, the bike is twenty-three years old and it shows. Skinny telescopic forks up front and twin shocks at the rear coupled with weight that pushes the 250 kilo barrier means that despite a golden racing history this is no race replica. The eighties were a real watershed when it came to motorcycle design with Suzuki ready to lead the way with the devastating GSX-R750 in 1985.

Even so the Kat can be excellent on medium to long sweepers, although the caveat here is that the suspension has to be in top condition. It'd be fair to say Kats take a bit of muscle in order to change direction, after all they have a rake and trail of 28.2¼ and 118mm, so there's always a sense of stability despite skinny tyres and small contact patches. Simply put the dated suspension doesn't deal with uneven surfaces well, but as you lean further and further over you get that wonderful swooping sensation that only comes with big lean angles achieved on big long curves on big long motorcycles.

Comfort isn't really the Kat's strong suit, the clip-on handlebars punish the wrists, although the footrests are well placed below the rider's spine, although tall/old riders feel they're too rear set. Anyway the low seat isn't too bad, but by the time you've covered the 250 or so kilometres to reserve you'll be glad that tank isn't any bigger. And it's not just the riding position, they vibrate, especially when fitted with a four into one exhaust. The well-tuned bike in the photos had the original four into two exhausts and it really was commendably smooth,

As for stopping, the three slotted 275mm discs and single piston calipers are simply overwhelmed by the bike's 250kg wet. In their day, which would have been when everything was new, a Kat could stop from 100kmh in about 38 metres and received accolades from all who used them. In fact Kat racer Robbie Phillis was renowned for passing pukka GP bikes with late braking on standard brakes. Steel braided lines help, but the bottom line is that age hasn't done the brakes any favours. 

WHAT GOES WRONG AND WHAT TO LOOK FOR
The Katana engine is basically the GSX1100 engine. It uses narrow valve angles and a shallow combustion chamber giving a compression ratio of 9.1:1. Valve adjustment is by screw and locknut. There are four 34mm Mikuni carburettors and ignition is electronic. What this means is that, armed with a manual, just about all servicing and most repairs can be done by a home mechanic.

So what goes wrong and what should you check when buying? For user information we went to our friends at the Katana Australia web site who posed the question to their members. First up the most common fault is the alternator, which has a propensity to burn out followed by regulator/rectifier failure. Symptoms are the battery struggling to turn the engine over and the lights getting noticeably brighter and dimmer with increased revs. Ultimately it just won't turn over and start.

Chances are the clutch will rattle - for the most part this is normal. What happens is that the clutch basket has six springs in the back that compress and loosen over time. However if you're the type that would race a paper bag on a windy day then you should consider beefing the clutch up, as when the standard item lets go, chances are it'll take the oil pump out to lunch too.

Check for oil leaks before and after a test ride, as the GSX engine can leak from the cam chain tunnel at the front of the engine and while you're up close and personal be sure to check that the frame on the left hand side just forward of the side-stand doesn't have a crack in it. Although the symptom is a somewhat loose feeling in the handling and excessive vibration it's easy to miss. How do I know this? Let's just say that it was a problem with the earlier GSX1100 as well.

Obviously a test ride is a good idea as it lets you test all the gears. Gear changing difficulties can be an indication of problems with gearbox bearings. Depending on whether the bike is standard and many aren't, second gear can spin on the shaft, a problem that will necessitate pinning the gear. So pay particular attention to loading the gears during the test ride. Also while you're riding the thing make sure it stops under hard braking. The bike should stop in a straight line and there should be no pulsing at the lever or metal-to-metal sensation. If the bike pulls one way or the other a brake caliper could be seized. Get up to a reasonable speed and take your hands off the bars to see if it starts to wobble, If it does, the tyres could be under-inflated or worn unevenly. Find some bends and see if the bike favours going one way over the other, any problems here could mean the chassis is bent. If there's a gradual weave at low speed - it could mean the steering head bearings are worn or overly tight.

Check that all the electrical components work and have a good look at the wiring around the headstock, under the tank and under the side covers - there should be no rolls of gaffer or insulation tape, a sure sign that wiring is giving trouble. Make sure that the wiring has enough free play as you turn the steering from side to side as it will pull connectors and even break wires.

Apart from these things you should always check the overall condition and make a note of any consumables that will need replacing for the simple reason that you can reasonably haggle over the price.

MODIFICATIONS
Just like the Bandit 12, which incidentally can be converted into a stunning Katana look-alike, the Kat is a perfect candidate for modifying. And there's a ton of accessory and tuning options still available. A lot of owners go for more performance via the big bore kit, pipe and tuning route. The simple fact is that it's the running gear that benefits the most. Better suspension and brakes would be high on the list with some people fitting complete front ends from Bandits and GSX-Rs. Others have replaced the twin shocks with a mono-shock and wider wheels, all of which makes sense if originality isn't high on the agenda. However if I owned a Kat I'd be looking at some low-key improvements like a fork re-valve and quality rear shocks. After that I'd be investigating bigger discs, modern calipers and master cylinder plus some quality tyres. After that - I'd probably just pose about on it and enjoy riding one of the most special factory specials ever made.

WE RACED ONE - MICK HONE
Back in the early eighties Mick Hone was running a Katana in the Australian superbike class, we asked what he thought of the Kat.

"The Katana was the bike to beat in the golden era of superbike racing and won multiple Australian championships with Robbie Phillis riding. Phillis held just about every lap record worth holding and could take on GP bikes on the Katana and win. Back then there was a heap of road bike based competition in the form of Kawasaki Z1000s, Honda CB1100Rs as well as oddball stuff like the shaft drive Yamaha XS1100. Those were the days when anyone could get the bike of their choice, spend a little money and if they were good enough go out and win. We'd build an entire bike for what they spend on a swinging arm these days."

"The Katana was reliable and there were lots of option to upgrade with. For its era it was good looking and it was the bike to own."

Our thanks to Mick, Ziggy and the Katana Club of Australia for their help in researching this story.

TRANSMISSION
Type: Five speed, constant mesh
Final drive: Chain

DIMENSIONS AND CAPACITIES
Weight: 252kg (full tank)
Seat height (claimed): 775mm
Fuel capacity: 22 litres
Wheelbase: 1520mm

PERFORMANCE
Power: 108bhp at 8500rpm
Torque: 9.8Kg.m at 6500rpm