Home was reached in one piece but only just judging by the engine noises. The clutch’s retaining screws were loose to the point of almost falling out. The plates looked like brand new, the previous owner obviously hadn't a clue. I roughed up the plates and took a file to the slots and tangs to clean off some burrs. I went over the motor, checking the valve clearances, tweaking the camchain tensioner and balancing the carbs.
The gearbox worked as well as a similar era Honda, which means not at all well but after a bit of practice it became plausible. The clutch was heavy and remote enough to worry grannies on crossings when the bike suddenly surged forward and caused me serious embarrassment when it stalled the engine.
The electric starter whirred the motor over, either hot or cold, with some desperate noises, until it caught just before the battery went dead. Sometimes, from cold, it’d refuse to start altogether, others it'd run very roughly. Checking the silencers on the 4—2 exhaust I found that one side had a lot less pressure than the other. I suspected the spark plugs. Someone seemed to have glued the fuel pipe on to the tap, as I pulled and twisted the tap popped out of the tank. Two gallons of Shell's finest went everywhere.
The underside of the tank was rusted. Aha, thought I, obviously some rust getting into the carbs. Removal of the air filter appeared impossible but after a screaming fit, that had the other neighbour twitching her curtains and wondering about the effect on her house price of living next to a lunatic, I finally pulled the filter out. After all that the plugs looked fine. The base of the tank had some thick steel sheet welded in and the tap secured to a welded on spigot.
After all that, the bike didn’t want to start. A lot of rumbling from the exhausts but no running engine. It sounded like it was firing only on two or three cylinders. I took the tank off, fitted four new spark plugs, to no avail. I tried everything I could think of but no joy. Obviously a serious engine problem. Engine out, cylinder head off and no apparent horrors.
I stormed off in disgust. Flicking through back issues of the UMG, to calm myself, I came across a story on an old CB250 with a similar problem - cracked carb manifolds were the answer. Cracked carb manifolds? It couldn't be that simple, could it? I rushed outside to check them. Yep, two had tiny cracks. A bit of car hose was found of the same diameter and, after putting the engine back together and into the frame, it was all systems go.
The engine started easily, ran much better and would push the bike to over 110mph, at which point the speedo exploded. I couldn't believe it! One moment I was congratulating myself on the speed, the next there was just a loose needle bouncing on its stop. The mechanism had fallen apart, either through old age, vibration or the unaccustomed velocity. A used speedo off a Guzzi had the same fittings and showed the correct speed and mileage.
The handling was good, in the Italian way, as in having suspension so stiff that each and every road shock jarred my spine but the wheels went where they were pointed and the bike could be heeled over far enough to cause the stand to dig in. When that happened the whole bike was jarred, causing me to drop a load the first time it happened, but the Benelli treated most such intrusions with contempt and could easily be pulled back on line. I was soon riding like a lunatic, having dices with things like GS550s and CB400Ns - no problem!
Well, no problem until the whole electrical system broke down. The first I knew about this was the back light blowing and some kind cager coming alongside, sounding his horn and going into a frenzy of signs which finally got through to me when I glanced backwards. A minor adjustment of the stop light switch left that permanently on and got me home without being bummed.
Replacing a rear bulb should’ve been simple but when I gave the wire a gentle tug I had a handful of a yard’s worth of disintegrating wiring. I knew what was going to happen; just knew it. Sure enough, every electrical component I touched either fell apart, was obviously in need of replacement or was so far gone that it was melted to the frame, only removed by destroying it.
There were some incredible bodges - I don’t know if they were stock or past owners taking the piss. The starter for instance worked through three different relays, one connection made by a bare wire that was just waiting for a chance to short out and burnt the machine down to its wheel rims. I obviously had a lot of past sins to pay off, two weeks of madness, with the help of the local nerd (computer hack, electronic genius), followed until a much simplified electrical system was installed, which included wiring the handlebars up with a 10000V shock as an anti-theft device. I once saw a cat crawling over the bike receive a shock, ended up laying on its back with its paws in the air. Ooops!
A bit of serious riding followed the electrical rebuild. The one thing I didn’t like about the Benelli was the seat/tank interface. The seat was a nasty piece of crap that went painful after fifteen minutes and I always felt perched way above the chassis rather than being part of it. The shape of the tank didn't help at all, leaving my knees widely splayed. If it was full of petrol, which with 35mpg economy it usually needed to be, fuel would spray out of the cap into my groin. Charming!
I found the best cruising speed was around 80mph, above that quite heavy secondary vibes poured in, much heavier than a CB500/4. Poor engineering I’d guess. Either the reciprocating masses were higher or they weren't well balanced. The Japanese can't be beat for mass producing components to within tiny tolerances. At the ton the vibes were trying to break the handlebars and make the pegs fall off. OK for a brief burst of acceleration but not much else.
I was never entirely confident in the bike, there was an impression that at any moment something serious could go wrong without warning. For the first time I joined the AA. The next hassle was the front end, every time I used the brake there was a disturbing graunching noise as it finally hauled us to a stop. There was no obvious cause for this so I had to take the calipers apart - it was one of the pads cracking up, a potentially lethal fault.
With a bike of this age there are all kinds of potential horrors cracked wheels, broken frames and any number of faults that could cause a seizure. It was pretty obvious that the 504 wasn't built to a very high standard and the more I rode it the more worried I became about something nasty happening.
I must've had some kind of premonition, because bouncing my way down some country lanes, the handling suddenly went so bad that I thought I'd been transported back in time to my days on a Puch Maxi. I pulled over before I was thrown off. I nearly threw up when I saw that the right-hand shock was twitching around on the lower mount, the upper stud having sheared off. Had the shocks been less taut I would’ve been in real trouble - was this a design feature?
It wouldn't have cost much effort to weld a new mounting but I felt if one part of frame was so far gone there might well be other weak points in the structure. I stripped the bike right down to the frame, blasted it and checked it over. No problem, so a stud was welded in and the frame painted black. A lot of hassle, perhaps, but better safe than sorry.
After that I decided to sell the Benelli. I got what I’d paid for it, might've managed a bit more but I was just happy to move on to something else. A newish one would probably be pretty good but I haven't much faith in high mileage examples as they seem built down to a price, and just about anything could go wrong. A CB500/4 would probably be a better buy!
J. F. T.