People will tell you that these early Honda fours are classic motorcycles. Try telling that to my K2! On second thoughts, don’t breathe a word. I just realised what classic means temperamental, whimsical, mercurial and inconstant. Admittedly, the Honda came to me well worn, three years ago with 86000 miles of abuse. I should not have been surprised. The only reason I agreed to buy the heap was that it was cheap, £425.
The CB750 has classic spoke wheels. The rear soon showed its stuff by breaking up, sending an already alarming chassis into an almighty wobble. I once experienced a rear wheel blow out at 95mph, so decided I was relatively lucky that the spokes broke at a mere 65mph. The bike’s rejection of its rider occurred at about 30mph, after a finger stretching dose of braking on the single disc.
The car that was directly behind was full of skinheads, who were almost pissing themselves with laughter as they pulled me out of the ditch. Damage to the Honda was merely a few additional dents and scratches, the indicators having long done a runner. The rusty engine bars absorbing most of the shock by dissolving into several pieces.
If I had been richer I would have left the CB there. I was able to push it into a driveway and leave it there for a couple of days. Back home I joined the AA, waited for a day and then informed them the bike had failed. I arrived at the house at the same time as the guy in the AA van. Eventually, the trailer arrived and took us both home.
For some reason CB750 back wheels are as scarce as working Suzuki rectifiers in breakers. Luckily, there was a small company locally who specialised in rebuilding wheels. I had to wait ten days but was reassured by the HD spokes. Whilst the wheel was out the inevitable revelations occurred. The chain and sprockets were in an astonishingly worn state and the swinging arm had half an inch of sideways play. The latter was fixed with some washers and grease. The former by buying a new chain and getting some sprockets from the large pile in the breakers.
The rear sprocket was five teeth smaller than the old one, which made the gearing significantly taller. As the Honda wasn’t the kind of bike to take kindly to being screamed in wheelie mode from a GP start, this was no great loss. In fact, it meant there often wasn’t any need to go up through the box any further than third gear. The gearchange action had all the characteristics that you’d expect in a classic motorcycle, so the less it was used the better.
With the wheel fixed, I was looking forward to some serious mileage. This foolish optimism was quickly curtailed by the disappearing engine oil trick. In less than a 100 miles the oil tank was almost empty. The oil was pouring out of the gearchange shaft seal.
The Honda dealer said a new one would take about six weeks to arrive. The local bearing factor turned up a suitable seal in six minutes at a third of the cost. Pulling the old one out proved problematical. Only solved by a chisel and hammer act. A large dose of Araldite was used to secure the new seal and fill in the chipped alloy. There was also a slight leak from the cylinder head gasket, so the head bolts were torqued down to a most unlikely degree. In a rare moment of inquisitiveness, I pulled the air filter apart. It was so full of crud that I was tempted to buy a new one. Just as well I didn’t, as it proved impossible to fit back on. The engine didn’t seem to mind that nor that it was running on an almost straight through 4-1 exhaust.
A few days later a dose of fiscal madness occurred when I saw some Read Titan bits for sale. Half fairing, huge tank, single seat, clip-ons and rear-sets for £125. They were immaculate so I handed over £95. These went on without too many whacks from the hammer and so showed up the rest of the machine that I had to spend a week with Solvol and touch-up paint.
I didn’t mind about the lack of pillion perch as I had long since given up on women. The new riding position did a lot to quiet down the wilder wobbles. At speed the front end would go light, leading to a lot of head shaking, the extra weight on the front wheel helped calm the worst of these misadventures. With the big tank to grip between my knees, I felt much more inclined to throw the bouncing Honda about than previously.
Girling shocks and tightened up front forks would have given the bike a reasonable feel had not the tubular frame a distinct hinged in the middle feel when hustling hard in the bends. Nothing short of a different frame would cure this. Still, the bike was safe up to about 85mph, which was all the speed the engine could safely produce. High revs were invariably accompanied by secondary vibes, which rattled footrests and clipons. I did put 120mph on the clock for a few moments, but it wasn't the kind of experience I‘d like to repeat.
The clip-ons made riding in town a laugh a minute. But only if you were a masochist. The rear-set gearchange linkage also made the box even less precise than before. Further amusement was added by a clutch that dragged, stalling the engine at traffic lights unless you‘d previously found neutral. As the electric start was burnt out, frantic kick-starting ensued. The solution to all these problems was to ride the Honda like a youth on a tuned 125. The staid geometry and 500lbs of mass made a mockery out of such excursions.
About midway through my ownership, the electrics started giving trouble. I’m not too good on that kind of thing, so was rather disturbed by blowing bulbs and flat batteries. I tried to ignore it, hoping it would sort itself out. Daily bouts on the charger soon wrecked the battery and by the time I handed over the machine to an auto electrician, nearly all the electrical components were dead meat. The problem was with the wires’ insulation rotting, allowing the leads to short out. The alternator, luckily, was still OK, so the bike was rewired with car rectifier and regulator. I still had to suffer blowing bulbs and fuses from time to time and the battery refused to last for more than eight months.
At this kind of mileage the engine needed quite a lot of tender loving care. Every 800 miles the oil was changed, the points, tappets, camchain tensioner and carbs were adjusted. A full service took about three hours and wasn’t the kind of job a mechanically ignorant yob could perform with success. It wasn’t a good idea to ignore this service as the engine complained by vibrating and losing power. The chain needed a tweak every 200 to 300 miles and lasted about 7000 miles.
Having done over 30000 miles in three years without a major strip down of the engine, has proved that the CB750 has longevity and durability built into its design (even if it’s old fashioned, with hyvoid primary chain and separate oil tank). With over 116000 miles on the clock, the engine rattles, smokes and vibrates, but continues to keep running. I have a nice F1 engine in the garage, but haven’t had the heart to pull the old one out yet.
The chassis has had the usual complement of complaints bearings, front disc, dodgy finish, etc - but nothing a bit of workshop fiddling or bodging could not cure. Failing that, there are lots of spares from later Hondas that can be fitted, early Honda fours being too much feted by the classic crowd to turn up often in scrap yards. The bike runs best on Avon tyres which last for around 15000 miles. The single disc only needs a set of pads every 16 to 18000 miles and fuel works out at better than 50mpg. So, it’s quite a cheap bike to run in most respects.
I've been offered over £1500 for mine, despite the lack of originality. I still have the original chassis parts if prices ever reach Vincent levels. | was tempted to take the money and run, but experiences with more modern Japanese tackle have not been anywhere near as interesting as this old Honda. It’s such a difficult bike to ride on the pace that I always end up with a feeling of satisfaction after every journey. And I like the feeling of knowing every rattle, knock and creak of the CB750. I'm happy enough with my twenty year old classic!
William Gray