Race preparation for a Suzuki 500


Firstly, some background. Suzuki realised the strengths of its Cobra motor way back in 1968. They called their racing 500 the XR-05. Sounds like something built to break the sound barrier and it nearly did. When they brought the XR-05 over to Daytona it was good for 152 mph, the sort of performance that made the American and British manufacturers sit up and take notice. Despite their performance the XR-05's were little more than souped-up T500 motors and that bodes well for interested Post-Classic racers of today. The T500 Suzuki is built solid, is reliable and as a result of its popularity as an economical and long-lasting commuter come tourer is still in plentiful supply second hand.

The best way to go is to find someone with a race-prepared bike and be prepared to pay their price, believe me, if they've done the work, then it is the cheapest way to go. Failing that and their aren't that many people who want to part with their hot T500s, look for a couple of old dungers and start the long path to a fabulous race bike. Once you've found a bike, strip it down, check the motor and have a close look at the wheels, brakes and frame.


The Exo-skeleton.

Check to see that the frame is neither bent nor damaged, clean off the rust and get rid of everything extraneous except the engine mounts. You don't need the standard seat mounts, side cover mounts, centre stand or side stand mounts or the battery/oil tank mounts, get rid of them all. Grind or cut them off, soon you will have a lovely pristine frame which will look custom-made when finished. Don't forget to cut the lifting grab-handle off as well. No macho self-respecting racing motorcyclist would have such a practical device on their machine.

Serious attention to the handling can now commence. The suggestions I make are for backyard mechanics only so I don't go to the extent of bending tubes and re-aligning steering-head angles. Firstly, the Titan frame is open and spacious, wide-open in fact! Some consideration to triangulation can be given by welding one inch (or so) pipe from just above the swing-arm plate on each side to meet the top frame rails about the point where the single steering head support bar meets the top rails. If you are going to mount a shorter swingarm then you will need to relocate the rear mudguard mounting point which is on a cross bar between the two rear frame tubes. A super little touch, that looks so right that people will think the factory did it, is to cut the rear mudguard mounting cross bar off the rear frame tubes and reweld them to your new triangulating frame tubes, both to brace them and to more effectively mount the rear mudguard. The mudguard mounting has to move otherwise the shorter swingarm will bring the rear tyre into contact with the mudguard.

Yes indeed, a shorter swingarm. The Titan has a monstrous wheel-base of 57.2 inches so the loss of 3 or 4 inches at the swingarm can only serve to quicken steering and reduce flex. You can make your own or modify the existing one, there is plenty to play with. I toyed with fitting a 350 Suzuki swingarm, it is the right length and takes the same wheel. I never got around to it. Once you take a few inches out of the arm weld some angle iron on to it to strengthen it. It weighs a ton but then so does the whole frame. It must be made of stovepipe. The T500 frame is heaps heavier than the Honda 750 frame I'm fiddling with at present.

Once you've moved the back wheel forward then you will have to re-locate the rear shock mounts as they will be too far back. Cut the rear frame extensions, take out an inch or two and reweld them back on to regain the appropriate angle for the shocks to work properly.


Rolling along.....

Unless you are keen to run a front drum brake then I suggest that you go for discs. Disc brakes are so must easier to maintain, are lighter, work better in all conditions and are plentiful. That is of course unless you follow the adage, "what do need brakes for, they only slow you down"?

The Titan comes with a handsome twin leading shoe front drum. If anyone wants one I've got a shed full of them. Try and find a traditionalist who wants a good looking front drum brake and sell it to him. I set my fastest laps on a drum braked Titan many years ago. Of course then I didn't know the meaning of "slow down" and didn't really notice that I didn't have any brakes after the first corner. Really serious work with the Titan drum brake led to cracks in the hub apparently, though it never happened to me. Of course the true aficionado can go for the GT750 Suzuki 4 leading shoe drum brake; but has anyone noticed how much they weigh, how long they take to set up and how quickly the shoes wear?

Or you can go the Grimeca 4 leading shoe drum brake way if you have lots of money. None of them look anything remotely like the TR500 Ceriani racing drum brake anyway (which is unobtainably expensive) while the Suzuki front disc brake setup looks just like the 1972 Suzuki factory Daytona setup and is heaps more practical.

The first disc-braked GT750 Suzuki had a twin disc brake front end which works very well on the Titan racer, even if two discs make for a lot of weight. They look good! The first disc-braked model GT750 had big, heavy disks with smaller cutouts in the centre. They look authentic; but they are hard to find and are heavy! From then on all the GT model Suzukis had slightly lighter disks which only pedants could distinguish from the first batch.

If you don't want twin disks then the GT500 Suzuki and the GT550 Suzuki shared single disk setups and similar forks. All the GT750's, GT500's and GT550's ran 35mm diameter fork legs on their disk- braked models and the triple clamps are interchangeable. The disc-braked model front triple clamps slot straight into the T500's headstock. Take the opportunity to replace the steering head ball- bearings with tapered roller bearings while you are at it.


The author gets his Titan based racer over

The 750 forks are a bit long and so they need to be run though the top triple clamp a way. They are also a little stiff for the 500 so change the oil and look for softer springs. Either way they will work for you with little effort. Silkolene RSF fork oil comes in a range from 2.5W to 15W. I go for 10W. AtA $18 a litre don't spill any. The best all round ride comes from the GT500 forks, they are softer running than the 750's. The advantage of the GT550's forks is that even though they normally come with only a single disc they often have the twin disk fork sliders allowing you to upgrade if so desired.

The standard Titan forks are 34mm jobs that are somewhat soft and spindly. They look quaint though with their external spring, though I recommend that you keep the dustcover on. Later forks, discs and callipers from the GS Suzuki range are not eligible for the Post-Classic class.

Feel, with the disc brake front end is vastly improved by the addition of braided steel hydraulic lines and joints. I've one set with braided lines and another with standard rubber hydraulic lines. Each time I ride with the standard lines I come in off the track complaining of sponginess. There is nothing wrong with them, the braided lines are just so much better. I get mine setup through Pal and Panther Cycles in North Perth, I'm sure there will be a place near you in other cities to do the job, it is worth it. Pal and Panther supply the brake pads and hydraulic fluid as well. Ferodo pads are the go at A$30+ a pair and Silkolene hydraulic fluid is the recommended oil.

A steering damper is a useful aid to help dampen out those bumps, especially on country round the houses circuits. I've used both the hydraulic type, which start working when the front end starts slapping around, and the friction type, fully adjustable, which works all the time, and presumably stops the front end from slapping around from the beginning. I haven't noticed a great deal of difference; but I do like the friction damper, made by Sebac, and sold to me by the late Ted Stolarski from Moto Guzzi Australia in Victoria Park, W.A. for around ninety bucks. Cheaper than the hydraulic units and if it good enough for the 4 valve Magni Guzzi at Daytona then it is good enough for me.

Fit a front mudguard, it makes a world of difference. Not only does it stop mud and sand from getting all over the motor but it also braces the spindly fork legs just a smidgen.

Rear shocks always need replacing and the standard Post-Classic racing replacement part seems to be Konis. These Koni shocks are normally very stiff, come with some damping adjustment, take a long time to bed in and they come in a bewildering range of spring strengths and lengths. The recommended rear shock varies on the weight of bike and rider. The stripped down Titan is around 165kg and I am pushing 80kg and my Konis are too stiff. I am using 7610 - 1307 with a 214 spring which is the standard GT500 setup. Other suggestions are the Koni 7610 - 1282 with a 240 spring for a much softer ride or the 7610 - 1514 with 70/100 springs. I have ridden the Titan with good condition standard Suzuki shocks and springs, they work okay as long as you don't expect miracles.


Rims, well if you want to look flash then alloy rims are mandatory; but for my money steel rims are cheap and durable. I use two different types of rim, DID and Akront WM2. Both weigh a bit less and look more pukka, Akront more so. The Titan has a 19" front wheel so re-spoking to 18" is the way to go for quicker steering, good looks and a better range of tyres. Craig Howe from Pal and Panther is the man to see locally for both rims and tyres for Suzuki 500's. If you haven't got a wheel, he can build one up from the new twin disk front hubs he has in stock. DID alloy rims cost around A$130+ each and the flash Akronts about $180. Add in wheel building and spokes when you do your costing.

Tyres are a toss up as most brands these days are pretty good. Dunlop K591's provide good grip in the dry; but maybe not so good in the wet. Dunlop K124's and K164's are pretty well the best you can get if you can get them and can afford them. No-one seems to bring them in anymore. I found them excellent to start with; but they wore real quick and went off real quick. Good for a few sprint races then they should be discarded. I think it is too hot in Australia for Pommy sprint tyres. Too expensive anyway.

Avon AM22 front and AM23 rear are a good pair. These Avons have a very good profile, they grip well and they are long-lasting. I have been very impressed with these tyres which have given me my best times at Wanneroo. I still have them on after two seasons and they are the tyre I recommend to other riders.

Despite this Craig Howe is fitting some Bridgestone BT37 Battleaxe's, from his famed Wall of Tyres, to the bike at the moment; the Avons will stay on the spare bike, so I will let you know how the Bridgies go in due course.

Darryl Beattie started small as well

Clothes maketh the man....

Clipons are de rigueur, though even after the above mods the T500 will wallow in bends and flex in the esses. Long ones give more leverage, forget the Jarno Saarinen replicas you'll will need all the help you can get to go fast and hold the beast on line. Alloy clipons are very smart and expensive. Don't buy second hand if they have been down the road. Steel clipons are readily available, repairable and heavy. They are also getting quite expensive. Expect to pay $80 for a set from a shop and not everybody carries them these days as modern bikes usually come with their own unique setups. Early Ducati Pantahs wore 35mm forks and clipons and they seem to be frequent sellers at swapmeets or wreckers.

Rearsets are the mark of the real racing machine. The Suzuki T500 is readily adaptable to a rearset gear linkage and the recent trend to sporty roadbikes has made the job easier. Any wrecker will carry a range of old Suzuki rearset gear levers and linkages from Katanas or even boring old farts such as the GSX250. These linkages sell for A$10-20 and are ideal. The gearshaft size and fitting is the same on these newer Suzukis as it is on the T500. Thank goodness for some standardisation over time. The rose-joints work wonderfully and often the only change needed is to extend the connecting rod. The brake is more difficult to fit as you will need to handcraft a foot-brake to suit. It isn't important as the back brake works so poorly anyway despite skimming and fitting new linings.

The T500 tank is quite handsome and will do if you can't find anything else. It is a bit short though if you go in for rearsets. A racing seat is essential to look the part and anyway you will need it to stop sliding off the back. If you can weld or know someone who can aluminium then a standard trick is to knock up an alloy box for a petrol tank and put a fibreglass dummy tank over it. Ok if you like that sort of thing. I don't like fibreglass tanks so I always look around for suitable metal ones. Old racing Yamaha ones look good; but my favourite is the early Ducati 750SS or 900SS tank. It is light, metallic, racy looking and fits straight onto the T500 frame. It is also the right length to suit a rearwards seating position. To fit it all that is needed is to weld a strap in place to locate the Ducati mounting bolts. You can still get to the plugs and head-bolts with the tank in place.

Of course if you put a Ducati tank on then a Ducati sports single seat really sets off the tank and the recess under the seat makes for a handy place to locate the oil tank for the oil injection system. I use old lawn mower petrol tanks. They are metal, hold just the right amount of oil, can take the vibration and of course they fit under the seat.

Copyright reserved: M Barnard 1990


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