Wednesday 22 January 2020

Yamaha RXS100


Buy an old Yamaha RXS100, ride for a year, taking the time to do it up so I could sell at a nice profit. Yes, I’ve been reading the UMG for a long, long time. This theory led me to purchase an eight year old machine for £75. The engine ran well for the 39000 miles on the clock but the chassis was in death rot mode. On the road home, the bike veered all over the shop and reminded me of my days on a dilapidated pushbike. After five miles my whole body had been given a good working over. 50mph was twice glimpsed on the speedo. Promising...

After some work with the wire brush, emery cloth and paintbrush the chassis looked less likely to corrode underneath me. The vile handling and fading brakes were sorted with new chassis bearings and a used set of shoes. There are plenty of cheap bits in breakers for this model and also lots of hacks that can be bought for less than £50 for spares. Age had crept into the cables, first throttle then clutch then brake snapping. All in the first week! The throttle went in town where I was able to throw the bike into the gutter. I bodged the carb so that it ran at 3000 revs, needing a certain weirdness on the clutch and gear change. The snapped clutch cable didn't really faze me, I rode around quite happily for a few days before buying a replacement.
 

The snapping brake cable was more serious. Like it went when I had to pull up hard for a junction. Instead of stopping I went straight into the side of a car, at about 25mph, and then over the handlebars. I was only glad that it was a BMW and not a Volvo, as the former gave quite a lot. Bent wheel and forks plus a lot of grief from the cager and our insurance companies. Used bits from the breaker cost £40. I went to the great expense of buying a new brake cable, not wanting to repeat the experience. The back pains and headaches took over three months to go away. I'd gone right over the car and landed funny on the back of my neck. On the advice of a friend who's into alternative medicine I suffered an acupuncturist sticking needles in me, which only made things worse!
 

With the chassis and brakes in good fettle I was able to take the little stroker right to the edge of its performance possibilities. Which meant 70mph and the Taiwanese tyres twitching on their edges. A new bike might've grounded its stands but mine had been dumped, probably fallen off. It was much safer to stick to less than 60mph, when the motor was smooth instead of trying to rattle everything off the chassis and the handling was quite reasonable. That is, it didn’t try to run off the road or play chicken with oncoming cagers and it didn’t shake its back wheel like a Pekingese lifting its hind leg when in an affectionate mood.

As I neither wanted to blow the motor into a trillion pieces nor end up on a mortuary slab, a bit of restraint on the throttle was the order of the day. Fine in town, where traffic moved so slowly walking was faster than a car, but on the odd open stretch of road I often found some cager trying to tail-gate me. Small bikes should do at least 80mph to survive out of town. Having to ride on the edge of the road's no fun at all. I was so worried by this that I fitted an extra back light on the rack, wired into the stop light circuit. It was a big bugger and a few taps on the brake lever had cagers shielding their eye. It kept them from bumming me, but if used when the lights were turned on the motor cut out. The rudimentary electrical system wasn’t up to much and the bike was only really safe, at night, to ride in town. On the good side, the electrics were so simple that even I could understand them, the few minor electrical hassles easily fixed.

People always looked at me as if I should be strapped in the electric chair. Something to do with the heavy smog the bike left behind, especially in town. At times, when idling on the bike and the wind blew the pollution over me I could understand their anger. I used the cheapest stroker oil I could find because it went through the motor at 75 to 100 miles per litre. I always had to carry a bottle with me.
 

Around 47000 miles starting became very difficult and the motor took to cutting out at idle. I was pretty sure, from the smoke and high level of piston slap, that the bore and piston were well shagged. The breaker had a good set for £20. I spent a pleasant afternoon grinding the faces of the head and cylinder flat so I could discard the cylinder head gasket but was slowed down by the need to have the threads for the studs helicoiled. The exhaust carbon was also cleaned out.

The reassembled motor had a lot more sparkle and a lot less effluence. It still topped out at only 70mph but getting there was a lot quicker and I felt quite happy holding 60 to 65mph for long periods of time. The drum brakes were annoying when used from such speeds as they would fade away to almost nothing. Either age or the increased vigour on the throttle caused the small end bearing to go at 53000 miles. By then my year was almost up so I tried not to pay attention to the big-end which had the conrod wobbling on the crankshaft. A new small-end bearing revived the motor long enough to trade-in at a dealers for a two year old RXS. The bike was priced at £850, with £275 off for my old one. A good deal, I thought, because the clock read only 7800 miles.

It’s interesting to contrast these two machines. The new ’un did 75mph, ran so cleanly I thought there wasn't any oil in the tank, and gave 120mpg against 75mpg from the old bike. The chassis was much tauter with none of the weaves, the lights seemed brighter and the drum brakes only faded after really hard use. An altogether better steed.

Or it was until 14000 miles when the damn motor seized up on me at 70mph. I hit the clutch in time to avoid self-immolation on the tarmac. After getting the bike to the dealer's in the back of a Transit, a faulty oil supply was diagnosed and the bike fixed with used parts - I had to pay about £25 for the bits but the labour was thrown in for free. Quite generous, I thought, as the dealer was moaning about how my old bike’s engine had gone in a big way and he’d had to install a used motor.

After that little adventure I lost faith in the Yamaha. It didn’t run as smoothly as before, causing me to motor along at less than 60mph again. It was still heaps better than the first one and would probably have happily run to 50000 miles without complaint but I was ready to move on to something bigger.

That turned out to be a derestricted AR125. Fun and much safer on the open road. As a first bike or basic transport the RXS100 is a useful device, as a serious motorcycle it has some significant shortcomings. There are lots on offer, plenty of room to make a bit of profit out the game if you put in some effort. 


James Carney