A steering damper, but not as we know it. . .

Words and pics by Simon Bradley

Minimalist packing is better for the environment, apparently. We think it's just so you can see how trick the thing looks before you buy it...Steering dampers are one of those things that provoke different reactions in people depending on their age, their biking history and riding style. If you’re a little older than me, for example, then you’ll immediately think of a big knob on the top yoke that rendered your (in hindsight) evil handling, tank slapping, under braked and under powered classic bike into something which remained at least vaguely controlled over bumps. Even if it did take an Herculean effort to get it to turn. While my peer group will immediately think of bolt-on dampers, usually on the left hand frame rail, which transformed our (in hindsight) evil handling, tank slapping, under braked and overpowered latter-day classic bikes into something vaguely controlled though rather lacking in feel or feedback. Of course, those of you still in your first flush of youth – either literally or in biking terms – will see steering dampers as either fashion accessories, usually mounted across the front of the tank in the style immortalised on the Ducati 916 or as standard fitted items on some of the more radical sportsbikes now on sale.

But how do they differ?

Well, back in the old days, when men were men and suspension consisted of a couple of coil springs under the saddle, a steering damper was a real necessity if you were going to remain out of the hedge. Technology being what it was, the engineers of the day came up with a fairly simple solution. At either the bottom or the top of the steering stem was a stack of washers. When you tightened that big knob on top of the bars, the washers got squeezed between the yoke and the frame, making the steering stiffer. Primitive but effective, though obviously vulnerable to corrosion and notoriously inconsistent.

The more modern type of damper, and one which you will all have seen at some point, works exactly the same way as the dampers in your suspension. A rod with holes in it gets dragged through a cylinder of oil. One end is bolted to the frame, the other to the yokes. More sophisticated dampers have adjustment, again just like your suspension, to make the damping stiffer or lighter. If they’re really top end products then there will be a way of keeping the oil and air inside apart. This stops the oil from getting aerated and losing its damping efficiency. The downside is that the damper rod is being pushed in and out of the body of the steering damper, and that means that oil gets pulled out and air gets pushed in. Both of these are almost inevitable and means that, over time, this style of steering damper degrades in performance. However, making a steering damper like this is probably the cheapest way of doing it while still retaining some engineering integrity and not reverting to the stack of washers and a long bolt principles of yore. Which is why those manufacturers who fit them as standard tend to choose this type of damper.

Out with the old - the original steering damper fitted to our GSX-R 750K7. The bolt on the left is the awkward one...Recently another type of steering damper has appeared on the market. Exclusively a factory fit item, electronic steering dampers hide under all sorts of acronyms but all provide essentially the same service – an adjustable means of damping steering movement. The electronic part gives them an added edge in that, sometimes, they can set an appropriate level of damping according to speed and throttle load. Sometimes, of course, they get it wrong.

But I’m not here to talk about any of these. Oh no. Because there’s a fourth type, currently undergoing extensive testing on our faithful GSX-R 750. And it’s a GPR rotary damper. Now I appreciate that normally the words “rotary damper” and “Suzuki” only appear in the same paragraph when accompanied by “huge mistake” or similar terms. Fear not, I haven’t lost my marbles. Though the presence of this device on the GSX-R does actually have something to do with the aforementioned huge mistake.

The mounting kit in place before fitting the new damper. You may need a proper socket for the headstock nut...Back in the mists of time, Suzuki launched a radical new bike. With a litre sized vee twin engine, aggressive styling and the sort of power output that had Ducati engineers choking on their cappuccinos, the TL-1000 was a surefire winner. One of the design moves, hailed as a real breakthrough, was the adoption of a rotary damper on the back. It was smaller than a conventional damper, more adaptable in its positioning and potentially a huge step forward. Except that it didn’t actually work terribly well. Some very high profile incidents where riders departed controlled flight under, it was claimed,  little or no provocation resulted in Suzuki recalling the entire lot and fitting steering dampers in an attempt to tame the bike. And now everything that comes out of the Suzuki factory, if there’s the slightest chance that it could be a little lairy under any circumstances at all, has a steering damper fitted under the lower yoke.

Now the damper fitted as standard to a GSX-R 750 isn’t actually bad. I could say the same about the steering dampers fitted across the range, because it’s essentially true. For a mass produced, one size fits all steering damper, the one fitted to Suzukis when they leave the factory isn’t bad at all. Nor, indeed, is that fitted to any other manufacturer’s bikes.

But it isn’t very good, either.

It’s not adjustable, you see, and that means that you’re either stuck with something that is nice at low speeds but totally pointless as you really start to work it or you get something that works where it’s needed but is rather intrusive at lower speeds. I’m exaggerating a little, perhaps, but that is broadly where we are as standard with the GSX-R - it does rather get in the way at lower speeds though as the pace hots up it's fine in isolation.

Mounted up and ready to go, the GPR stabilizer in position. Enter the GPR Stabilizer, a rotary steering damper that sits on top of the top yoke and keeps things under control via a weedy looking (but incredibly strong) arm that clamps into a post attached to the tank mounts.

First impressions are very good indeed. The GPR Stabilizer is beautifully engineered and finished, it looks suitably trick and the supplied bolts and fitting kit are of a similarly high quality – reassuringly there’s no sign of corner cutting.

Fitting is simplicity itself, though obviously that may be a different matter on other bikes. But on the GSX-R at least, the procedure is easy. Remove the standard steering damper. Just two bolts hold it in and they are both reasonably accessible. After a while you’ll realise that the bolt on the left has a nut you need to hold while you attack the bolt from underneath. That’ll be why it isn’t undoing, then. After that slight hiccup, draw the old damper out and put it to one side. Now undo the headstock nut (the big gold one) and take off the washer underneath it. Fit the base of the stabilizer, it will only go on one way, and refit the nut. Leave the washer off. Now undo the front mounting bolt on the tank and again remove the washer. Fit the stabilizer post, which again will only fit one way, and bolt it down with the supplied longer bolt. Don’t use the washer. Now bolt the stabilizer body to the top yoke, slipping the arm into the post as you do it. Finally tighten the pinch bolt on the post and you’re there. Ignoring the little blip with that nut, it's ten minutes tops to replace the standard damper with the GPR one.

Once it’s in place, the GPR Stabilizer looks even better. It comes in loads of different colours, so you should be able to get one to suit your bike, but the black one just looks perfect with the GSX-R’s black top yoke. In fact, it looks pretty well made to measure.

Couldn't look much more as though it belongs, could it? Moving the bars at standstill allows you to check the difference between minimum and maximum damping. There are twenty settings, but in honesty I can't imagine needing anything stiffer than the first five under any conditions short of nitrous injection on knobblies on a BMX track. Setting 20 needs some serious effort to even turn the bars. By the way, riding with too much damping can set up a slightly disconcerting weave as it takes too long for things to sort themselves out. It's not recommended at all...

Anyway. Getting on and riding is a revelation. With the GR Stabilizer set at position number one, giving minimal resistance, results in a bike that is so much easier to ride at low speeds than standard that you'll find yourself dabbing the occasional foot on your first trip as you turn in too early for everything. But that's not the real benefit. Oh no, the real deal happens as you start getting faster. Now I have no idea how this works, but the GPR Stabilizer seems to provide exactly the right level of steering damping all the way through the speed range. You like the feel of the original? OK, ratchet it up a few notches and you'll have it. Me, I like the absolute minimum of steering damping that I can get away with, and this will deliver exactly that.

It's not just the adjustability, though. Or even the bit of magic it performs whenever you change speed. It's the smoothness that really does it for me. While, as I said before, the stock item isn't actually bad as such, you always know it's there. Perhaps not at first, but as soon as you've ridden with something as smooth and sophisticated as the GPR Stabilizer the stock one feels as though it's damped with sand.

The GPR Stabilizer isn't especially cheap at over £350 but it makes a quite astonishing difference, adding a level of feel, feedback and sheer agility that you probably haven't realised is missing yet. And that is, quite simply, priceless.

SB

STOP PRESS You can get the GPR Stabilizer for £365 from www.trackparts.co.uk. If you're a racer and can prove it then you get a 10% discount.

 

 




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