It was my good fortune to pick up a 9000 mile Honda CB750F1. It was so cheap that I immediately decided, being of both a cruel and lazy disposition, that I would see how long it would last in total neglect mode. It took longer than I expected, given the poor reputation of this OHC four. I can only suggest that its early engine failings had been sorted out under warranty and its first owner had been meticulous about running her in.
Not being entirely daft I did concede 1500 mile oil changes and keeping the bike in decent tyres. I’d already had one bloody endorsement for riding my previous mount on bald rubber. I didn’t want to end up a confirmed felon, god knows what our extraordinarily warped justice system would do to me.
First impressions, then. Handling was heavy but stable. A remarkable feat given that the shocks were still original. The heaviness was expected, the bike weighing in at nigh on 500lbs. Top speed was a tolerable 130mph. By then both vibes and the chassis were making the Honda a bit twitchy. The rate of acceleration up to 120mph was impressive, the old dragon seeing off some quite modern 600s. Getting that final 10mph was hard work, needing a racing crouch and some determined throttle work. As well as along, straight bit of road. Given the state of my licence hardly worth the effort.
Speed was going to be adequate, bordering on being even great fun. It had a rough and ready way with the power that plastic replica bikers would find disturbing, but to someone who'd grown up on malcontent British bikes it seemed a natural extension of the motorcycling experience. It was nice, though, to be able to ride around without bits dropping off...
That was what I was thinking when the chain broke, some three miles from home. Being something of an old hand, I had a spare link in the toolkit. Being stupid, it wasn’t the right size, no way of getting the retaining clip on. I superglued the link plate to the pins. I was thankful that the chain hadn't whipped a hole in the crankcase, a common way of wrecking these engines. I rode home at 10mph, ever sensitive to the nuances of the transmission lurches.
The gearbox was something of an acquired taste at the best of times. The clutch was a bit too direct in its action and the cogs would show a reluctance to engage. On the good sign of leaping into false neutrals once they were home. As the chain wore out the gearbox became almost impossible to use which serves as a warning point for when a new chain should be fitted.
The chain that broke, on careful examination, was full of tight spots and had about six links missing. I later found that chains lasted very poorly, indeed, and I ended up taking links out myself even with the potential disaster of a broken chain. The cheaper chains could be out of action within 4000 miles and very conscientious maintenance allowed an expensive one to last 10000 miles.
As I was running the bike on a shoestring I was a bit miffed to find that the back tyre was equally short-lived. They were torn through in 5000 miles and it was a brave man who'd use an F1 on a rear tyre with less than 1mm. The front went for about twice that distance, but was even more alarming when worn out as the wheel would slide all over the tarmac.
Combining worn tyres with a misfiring engine in the wet gave me flashbacks to an old BSA B31 I used to skid around town on, only that one just had one cylinder to cut out and would go completely dead at the most inopportune moments. Rumour holds that the ignition coils are the culprit but as long as I remembered to spray the bike with WD40 it'd survive the worst the British weather could throw at us..
That's more than can be said for the calipers which, in all, needed seven rebuilds. The clever little nerd who designed the calipers should be taken outside and shot because they seized up in away that made them impossible to split without some very innovative use of the chisel and hammer. I redesigned them so that a bolt inserted would cause them to part in a matter of seconds.
The pads were actually long-lived, about 12500 miles which made the constant strip-downs all the more galling. The brakes were OK when they were working, nothing to write home about (or to the UMG, for that matter) but adequate for losing speed in a hurry, not likely to lock up the wheels without warning and only a predictable, controllable bit of wet weather lag. When the calipers started gumming up all that went to pot and just about anything could happen. Nasty. A length of Goodridge hose for the front brake eliminated a lot of sponginess at around 27000 miles.
A couple of impressive points about the engine. Between oil changes it didn't use a drop of oil. The points were never touched and were still original when the motor finally failed. The carbs and valves were left to their own devices and seemed all the better for it!
The suspension wasn’t so happy to be abused and neglected. The rear shocks, by 15000 miles, were causing a bit of derangement at the back, with weaves and wobbles, plus some thudding over bumps. I noted as I was investigating the back end that the swinging arm bearings were a bit loose, so as well as a new set of Konis some bushes were hammered in. The spindle had come out with a few gentle taps, even had a little grease left on it.
The forks were another story. The first sign of malaise was leaking seals from the pitted fork surface. The seals were not easy to get out or put back in without damaging them. After a month they were leaking again so I bought a new set of stanchions. The seals still only lasted for about 4000 miles a time after that and by 35000 miles I had to do a complete refurbishment, new bushes, heavier springs and yet another set of seals.
The new forks firmed up the handling, stopped some of the large weaves in fast sweepers and removed some vicious twitching over pot-holes. After a couple of years piloting the F1 I had got the handling down to a fine art, knowing exactly how far I could take the bike and knowing which weaves meant it was time to back off. I had experienced some deadly speed wobbles when the chassis was worn out, but it was just a matter of exerting muscle as the brakes were applied harshly. If I was going to fall off I wanted to do so at as low a speed as possible! But, by a combination of luck and skill, I stayed aboard the bucking machine.
Suspension apart, over three years of abuse I paid little attention to the chassis. I never cleaned the F1, touched the electrics nor did anything to the exhaust, which was as rusty as an old nail and by the time the end finally came full of enough holes to be useful as a cheese-grater. Even so, the engine wasn’t affected by the almost straight through exhaust... it was probably compensated for by the original, untouched air filter.
I did have to renew the spark plugs every 10000 miles to ease starting and stop some chronic cutting out, that even half a can of WD40 couldn't help. Right up to its final days the motor was still capable of putting 120mph on the clock and turning in 45mpg. Nothing special, perhaps, but you have to bear in the mind the level of near total neglect to which the Honda was subjected.
The end came at 47000 miles when the Honda looked like such a total rat that the local plod were pulling me over and using it as an example of neglect with which to instruct young traffic cops. Beginnings of its demise came at 39000 miles when the gearbox became really beastly, leaping out of second and third with a dangerous lack of warning. Changing from first to fourth really tested the machine's character and production of torque, making town riding a real pain. It would've taken a major effort to remove all the gunge off the engine just to get at the screws! The next chain change I put on a tiny engine and large wheel sprocket, which made fourth like third and therefore just possible to take off in it.
The final demise came from a rattling primary chain and knocking main bearings. I'd had three years of good biking but most F1s are too high in mileage to be worth bothering with, these days. If anyone’s got a crashed one with a good engine, though, drop me a line via the UMG.
M. Young