Friday 24 January 2020

Yamaha XJ900


‘Look, matey, I’ve just come 100 fucking miles to see this heap of shit that you described as immaculate...’ It's happened to me too many times. Read the advert, talked over the phone and turned up to find some old rat instead of the immaculate motorcycle lovingly described. I actually hit one guy and came close to it this time when I clocked the grime encrusted XJ900. If the owner had told me it just needed a clean I would've done for him!

Instead, he started the motor, let me hear with my own ears what a 19000 miler should sound like. A bit mollified by the lack of rattles I had a quick blast around the estate. It handled like a pig but accelerated like a phantom jet. XJ motors, with their well proven DOHC four cylinder layout, are generally tough. The chassis had degenerated into rat status, not unconnected with the fact that it’d been commuted 40 miles a day through the winter months without once being cleaned.

We haggled for a while, ending up with me reluctantly handing over seven hundred notes for the six year old machine. I rode most of the way home on one wheel, amusing myself with bursts of acceleration. The front brakes were locked up like they'd been attacked by a welding torch. The back was an exciting on/off switch, which broadsided 500Ibs of gunge into anything that got in the way. Engine braking was usefully fierce, a lovely drone from the Motad four into probably a minor miracle.

Of course, the first thing one does with such a rat’s to Gunk and jet-wash to find out the extent of the damage. Corrosion can run so deep on Japs that the frame’s close to breaking through. Most of the mess was surface rust and deeply mottled alloy but all the chassis bearings were loose and the suspension had seen much better days. I spent about £200 sorting it all out, ending up with an average condition bike for the year (1988).

The twin front discs still lacked power for a 135mph machine. Several times they faded away to nothing. That kinda woke me up! On one occasion I went roaring through a busy junction at 50mph instead of coming to a controlled halt. I didn’t even have the presence of mind to hit the horn, not that it can be heard over the rusted out Motad. More by divine luck than any particular excessive judgement, bike and I sailed through a plague of traffic. A few horns were blown and brakes screeched.
 

Old disc brakes are pretty nasty things. Rotted calipers, thinning discs and squelching hydraulic lines. I tried my best, would’ve been silly not to, but the restoration job was limited by pitted pistons and bores plus discs that were going so thin they were turning distinctly musical. Newish stuff a few months down the line provided a final solution that threatened to repeat its demise after the first winter. Both EBC and Ferodo pads lasted for a mere 6000 miles.

Handling was what you’d expect from a large multi that has its inspiration in the seventies Z1 and CB750. Stable in a smooth straight line, needing loads of muscles in the tight stuff and wallowing on long sweepers above 80mph. OK, brand new suspension might have made the plot better, but the Japs are a bunch of wankers - a few thousand miles on the clock of a brand new bike most often causes suspension slack and the same kind of weird handling. Any car manufacturer who tried the same trick would've been out of business within a year!

Moan over, I still managed to enjoy the XJ for most of the time, in a year’s hard charging of 22000 miles. The very good news was the toughness of the motor, which was given only oil changes and carb balances (I’ve got the vacuum gauges so that was cheap). With 41000 miles on the clock there were some quite harsh rattles from both the cam and primary drive areas but not so bad that they affected performance or the ease with which I sold the bike for a thousand notes.

Acceleration could be very heavy when the carbs were set up perfectly. Really a 500 mile job. After that secondary vibes cut through the chassis every time more than 5000 revs were dialled in. The hard stuff came in at 6000 revs, when the shockwave from the Motad knocked cats off walls and shattered milk bottles. It was a bit of a pain, the noise making more than the ton very uncomfortable; my poor old head left ringing.
 

The Motad eventually disintegrated, although it may’ve been there since new for all I know. The can went without warning, not exactly flying through the air. More like blowing up into a million rusted particles. The downpipes were also just about rusted through, a few taps with the hammer reduced them to dust. I had no end of carb problems with both a home-made four into one and a used stock system. Only got rid of the flat spots by fitting a used Motad. Doubtless the previous owner had changed the jets to suit the Motad. The used one was in perfect nick, replacing the previous bellow with a gentle growl.
 

The XJ felt more powerful than its reputation would suggest with a stunning surge at higher revs and quite a lot of torque below six grand. These traits were echoed in the exhaust noise which turned from a gravelly growl to a sublime roar. Addictive stuff. I just laughed at the protestations of friends on V-twins and triples about their claims that their engine notes defined the motorcycle experience. As mentioned, the engine also rattled, not for it the eerie whine of camshaft gears in more advanced designs.

Cruising speed was only limited by legal constraints. I hustled along at 120mph when conditions allowed. Having always owned old Japs, I didn't find the secondary vibes that worrying, though weaker jockeys might've been screaming about the way their feet and hands were buzzing. The riding position, with non-standard ace-bars, was more comfortable the faster I went (which was the only excuse I needed). Once I was used to the bike, which only really took about 500 miles, some great explorations were made.

One that stands out is an early morning thrash up around Loch Ness - you have to get up early to avoid the holiday crowd. A low mist had made some corners a bit dodgy and I nearly flew right off the road a couple of times. Finally, coming out of the mist on to along straight, with the Loch down below where eddies of mist twirled on the water's surface as if a whole platoon of monsters was emerging. My vision and attention were a bit distracted by the 130mph I'd putn the clock along the straight.

Just as distracting was racing with the BMWs and Mercs along German autobahns. What I lacked in speed I made up for in daring. I turned the weave into a snaking motion between the cages. The Germans have to be admired for their disciplined driving; god knows what they thought of the erratically ridden XJ900. some saluted with their horns and I rather fancy that one chap clutched his heart. The XJ finally tired of the game by throwing a speed wobble at 110mph. The trail of shit I left behind probably remains to this day, but after frightening half the German population to death the old bounder pulled back into line. I did the rest of the journey in the slow lane, if such a term can be used on a German autobahn. I did have a lot of mass on the back rack and there was a seam of some sort running across the road. Even German roads have their imperfections.

That event reminded me of the time when the front wheel bearings went. They’d been rumbling away for a while, although I thought it was just the speedo drive drying up or the discs sticking on. Really, I didn’t want to know - you get like that sometimes. I was two up with a pile of camping gear when the reality of their demise took hold. It was hard to ignore, with the bars trying to jump out of my hands and the front end wanting to go in two directions at the same time. The only good point was that we fell off at a relatively low speed and the woman used me to take her weight. Despite feeling like the whole bike was breaking a new set of bearings fixed it.
 

There were other minor irritants. Aren't there always? More than anything, though, it was the sign of engine problems on the horizon that caused me to get shot of the bike. It had needed quite a lot of work along the way but the overall experience was favourable. I might well buy another. Check for both chassis rot (especially those bearings) and engine rattles (a shot cam chain ain't a total disaster unlike a knackered gearbox - they usually last for at least 60000 but start rattling at half that mileage). I still see mine running around, so they are at the very least tough!

Mark Adamson