Monday 2 December 2019

Yamaha XS400


For some reason, every time I started my Yamaha XS400, dogs went crazy. I mean really mad. They would hurl themselves at the bike, leap over fences or come bounding down the road, fangs barred in a frenzy of hatred. Starting was often difficult, needing an excess of desperate kicks and the engine would often stutter for a few moments then go dead. Fortunately, I wore strong motorcycle boots. and could kick any mangy canines in the head without worrying about losing chunks out of my shins or catching rabies.
 

I even had one dog test the XS’s stability by charging head-on. I rode over its head with a lurid lurch that left the bars shaking wantonly for next 100 yards. A glance in the mirrors revealed a decapitated dog and some eager beaver of a ped trying to write down my number. I say trying because I always left the back end covered in mud.

The XS became even.more of a truculent starter if there was any water in the atmosphere, let alone rain. Spraying everything with WD40 helped a little but I often ended up kicking away for half an hour. The electric start had long ago burnt out. I'd rewired the ignition directly so there was no way anything could short out.
 

XS400s are infamous for their starting hassles and become worse with age. Once on the move they are not much more inspiring. For a 400cc vertical twin there’s not very much guts. I have trouble staying with Superdreams and something like a GPz305 disappears off into the distance. If there’s a hint of hard power above 7500 revs there’s also lots of vibration. The engine lacks any balance shafts but is smooth at lower revs. It may’ve been better when new, but I’ve had the bike for two years and 23000 miles and it hasn't gone any more vibratory in that time. The mileometer now reads 45000 miles.

The XS will just break the 100mph barrier. Just, as in down a mile long hill with a following wind. Really, trying for more than 80mph is too much work and the slightest obstacle will need a change down two gears and loadsa throttle work. The numbing vibration makes me think that the engine is about to explode, although against all the predictions it’s survived almost completely intact. Mostly, I think, because I change the engine oil every 500 miles!

70mph cruising is about its limit. I'd fitted cow-horn handlebars to aid town riding as I found the stock bars hurt my arms after fifteen minutes in heavy traffic. The replacement bars were very painful at 80mph, and above, leaving my shoulder muscles feeling like I’d been on the rack. That was okay as 90% of my riding was in town or down slow country roads.

The wide bars were an aid to controllability because the XS had more than a passing resemblance to a tea-trolley on occasions. I always took great pride in fitting the cheapest of half worn tyres I could find, which were usually of Far Eastern or Russian provenance. I was often given them for free. The XS’s chassis is not the most robust in the world, didn’t take kindly to my neglect in the rubber department.

Some lurid slides on wet roads made the daily commute through the grime infested East London district far from boring. I sometimes ended up twisting the bars in one direction whilst going in the other. A set of air horns encouraged car drivers and pedestrians to get out of the damn way, as did the knowledge that the old rat was worth next to nothing and in the event of an accident could be kicked straight without any worries about the cosmetics. This made the daily commute free from worry and full of a malicious kind of fun.

The only worry on wet roads was that the spray kicked up by passing lorries would engulf the engine, causing the motor to stop dead in its tracks. This invariably happened right in the path of sadistic cagers, who would bear down on me, beaming with repressed violence, expecting me to do a complete disappearing act. Hitting the air horns brought them back to reality and gave me the precious seconds I needed to push the bike into the gutter. Where I'd spend between 30 seconds and 30 minutes trying to kick the heap back into life.

The XS has points ignition which can go way out, but even when set perfectly still allows the starting conundrum. The timing can go so far out, in as little as 250 miles, as to make the power drop off to the point where no more than 50mph is possible. It does this trick best when pattern points rather than originals are fitted. I had one set of points wear out in 3000 miles. It also pays to put in new spark plugs every 1500 miles.

Similarly, all hell breaks loose when the silencers corrode past a certain point. Lots of backfiring, huge flat spots and a noise that gave even me a headache after a few minutes. Being a bit mean, I naturally ran the bike until the silencers fell off and then tried various rotted two into ones before a pair of universal silencers, bigger main jets and a chucked air filter more or less sorted out the carburation.

The whole chassis was susceptible to rusting. If it was made of steel then it was going to go back to dust. I always kept ahead of the demise by buying cheap used parts when they became available. As most of the bits are common with the XS250 there are plenty of parts, even whole bikes, around for next to nothing. The alloy didn’t actually fail, but took to itself a protective layer of corrosion. Some of that corrosion seemed to have reached the gearbox by 40000 miles. The six speeds were reduced to four or even three gears on some occasions. It was preferable to take off in second, third was OK but then it was a race to obtain top gear as soon as conditions allowed. Fourth and fifth would both disappear if a little bit of throttle was applied. Changing down the box was open warfare, as well as a multitude of false neutrals the box would occasionally lock into gear.

This all proved highly fascinating on a particularly blustery day. As well as trying to find a working gear I had a howling gale attacking the XS from the side. It should be mentioned that I'd fitted a huge top-box to the rack, which hung way out over the rear. The XS, on its skinny, worn tyres, was soon wobbling all over the place, with the power snapping in and out as the gears disappeared and the roaring wind caught the bike. The Yam weighs about 400lbs but that day it’d felt like a 100Ib moped.

When the wind turned and we were battling into it, petrol dropped to an amazing 35mpg, leading to me running out of fuel in the middle of the countryside. It was one of those days, when I wished I'd never got up. Pushing the hulk into the wind it felt like a bloody Goldwing, not helped by an ancient chain, half deflated tyres and sticking calipers. I could usually rely on 55mpg and well over 100 miles before desperately searching for a petrol station.

Running out of fuel was almost as embarrassing as the one time I had a mechanical failure. Admittedly, I was, for once, caning the engine at 85mph in fourth and pretending to ignore the tremulous vibration. It attacked every component on the chassis, as well as the whole of my body. I wondered where it was all coming from.
 

The next thing I knew there was a rat-tat-tat from under the petrol tank. It sounded serious, so I backed off but it didn't go away. Then there was Ioads of smoke out of the exhaust and lots of mechanical carnage inside the engine. Two days before I'd joined the AA who turned up quickly but then made me wait an hour for a trailer. Oh well, I got my money’s worth out of them.

After extracting the motor, the trouble was traced to a dropped valve, it'd also wrecked the piston. I already had an excess of bits, so the cost was minimal. I also replaced the selectors. That was at 43500 miles and the bike has bowled along for a further 1500 miles without any pain.
 

The best thing about the XS400 is that it’s cheap. I run mine as a ‘250’ (I bought a crashed one for £25) to cut down on tax and insurance. As a motorcycle it doesn't amount to much and wouldn't last long in my garage if I was rich. You can buy something that’s running for under £200 and find out the true story for yourself.

L.M.