Rumour holds that the old Honda CB500 four engine will fit straight into the Benelli 504's chassis. I don't know how true this is despite having owned a CB500 a long time ago. The engines do look similar and their power output is equally bland. The 500cc OHC across the frame four claims 50 horses but its delivery is so linear that it seems a lot less, there's never the feel of a motor coming on cam. Just like the old Honda, it'll put 80 to 85mph on the clock without any undue abuse, but going any faster is such hard work it's really not worth the bother.
The engine responded to juvenile tacho excess by needing valve adjustments every 500 to 750 miles and putting out a flurry of secondary vibes through not just the pegs and bars but also the seat and tank. The carbs kept their balance for about 500 miles and every now and again one of the slides stuck, which made the engine hunt between 1000 and 5000 revs!
Carburation always seemed slightly hesitant, a distinct delay between whacking open the throttle and the back wheel doing something. Its relatively primitive nature showed up in fuel that was never better than 40mpg. The dynamics of carburation, exhaust and combustion chamber shape were shown up when riding the 504 into a strong headwind; speed was down to 70mph and fuel up to 35mpg!
The motor always felt revvy as well, I was often trying to change up another gear when I was already in top. I could never persuade the Benelli to adopt a relaxed pace to match the parameters of its performance and chassis. The gearbox, with more than 15000 miles done, was neither slick nor precise; it mirrored, in fact, some old sixties Honda hack in its application. It was not impossible to adapt to, but even then would serve up a false neutral, which buzzed the motor like its poor old heart was going to explode into a million pieces.
The double cradle loop frame could have been produced by any factory anywhere in the world, but was well enough thought out to save the bike even when it was slung into desperate conditions by a sudden false neutral. The whole beast was held in check by famously stiff Italian suspension at both ends. The forks, despite their mileage still suffered from some seizing and responded to slow speed holes by sending concentrated jolts straight up my arms. The shocks did the same trick to my spine.
Smooth roads held no terrors for the Benelli, it could be slung over on to the stand prongs without the Pirelli tyres giving a moment's worry. The 504 had 425lbs of mass and slow steering geometry against it in the curves, but its stability and neutrality allowed me to take outrageous risks when I was in the mood.
This stability held it in good stead on bumpy roads. The rider took a battering but the wheels held on to their line in a way that the old Honda four could never hope to emulate - it used to waddle about on soft suspension, zig-zaging from bump to bump. As the Benelli never accelerated hard nor went very fast, any test of the chassis was limited but, apart from the lack of bump absorption, I was at ease with the 504.
Which is more than can be said for the drive chain. It always wanted to dissociate itself from the chassis, wore at an astonishing rate and broke three times when I tried to run them after removing links. They barely lasted 4000 miles. One time the broken chain busted into the back of the crankcases but I repaired that in-situ with good old Plastic Metal.
The only other chassis horror was the way corrosion would suddenly appear from nowhere, spread like wildfire until the whole component was covered in gunge. The frame, wheels and exhaust were particularly susceptible. The front disc calipers followed the trend set by the Japanese of seizing up over the winter, but they were easily rebuilt. Pads lasted 8 to 10,000 miles a set.
After a year's riding, various electrical components decided they couldn't take extended exposure to the English weather. Switches that filled with water, corroding contacts, made for amusing incidents such as the indicators flicking on and off in a psychedelic manner whilst the horn, normally nothing more than a croak, blared harshly enough to have pedestrians waving their fists in anger. The fuses either rusted to death, fell out or exploded.
By the time I was able to find the energy to rewire the bike, the generator was burnt out, the rectifier had melted, the battery was devoid of acid and just about every other electrical component had to be replaced. The breakers provided a viable source of electrical components, although I stayed clear of Suzuki bits. The most difficult part was persuading someone to rewind the generator but fifty notes in the right hands solved that one.
As the bike had to be stripped of all its cycle parts to access the electrical bits I took the time to rust proof and then Hammerite the frame. Some Scientific Coating's clear liquid was put on polished wheels, which meant that rather than a two hour cleaning session a week a quick wipe with a rag was all that was needed to keep them neat. A Honda CB500/4 four into one exhaust (thirty notes secondhand) was persuaded on to the Benelli engine but needed a bit of a pounding to clear the lower frame rails. It sounds lovely, but didn't increase performance.
Other complaints that could be levelled at the Benelli included a pathetic seat that went hard after 50 miles, wheels bearings that needed replacing every 6000 miles and a petrol tank that even when newish loved to rust rapidly - I'm on my third, one of them actually dropped a load of fuel over the engine. The bike sizzled for a while but resisted the urge to explode.
The Benelli was quite resistant to crash damage, as long as engine bars protected the ends of the crankshaft, the demise of either extremely expensive. I've slid off on diesel a couple of times, did no more damage than batter the pegs and bars. More serious was smacking into the side of a car that shot out of a road so fast it could only have done so with the sole intention of trying to kill me.
The front end hit the car, the sudden loss of momentum causing me to somersault over the cage, roll down the road a few yards and then pick myself up. I was full of craziness by then and would've torn the driver limb from limb, but the impact of the crash had warped the car's body so that none of the doors would open. There was a strong smell of petrol, so I tried to pull the Benelli out of the car with the intention of throwing a lighted match on the cage once we were at a safe distance.
Fortunately for the cager, there was no way I could pull the bike out. Someone had phoned the police so there was no hope of physical retribution. When the bike was finally pulled free, damage consisted of bent forks and dented exhaust, along with a bit of cosmetic damage. The cast front wheel was still intact. His car looked a write-off so I decided not to inform my insurance company which would stop his claim dead.
I had the forks straightened for £30 and cut and welded the pipes - they look a bit naff but matt black paint hides most of the damage. The smashed clock was glued back together with Superglue, as was one of the indicator lenses. This may sound dodgy but I've found it works fine from past experience.
This crash occurred about three years and 12000 miles into my ownership (the clock read 19,650 miles). The only result of the damage was fork seals that didn't last for more than 5000 miles (I hadn't had to replace them before). There was so little suspension movement that the lack of damping that resulted wasn't too noticeable.
Handling became more alarming when the rear shocks lost all their damping (at about 23000 miles). The back wheel would try to career off the road whenever I leant the bike over more than a few degrees on bumpy roads. It'll also jerk around after hitting a pot-hole. That was easily sorted with a pair of rather more compliant Konis. My spine was thankful for the diminution in violence of the bumps that got through the chassis. A slight weave occurred at 90mph, but this speed was never sustained for more than a few seconds so the weave had no chance of developing into a wobble.
A cheap rack and massive top-box were added for a while, but that did upset the handling whenever any kind of mass was put in the box. It didn't feel safe above 60mph. One blustery day, the wind shook the back end so much I thought the swinging arm bearings were shot, but it was just the gale catching the plastic. In the end I dumped the top-box.
That didn't help the touring ability. The shape of the tank meant that tank-bags slithered around all over the place, usually ending held in place by nothing more than its own weight and my knees. The only safe place to carry luggage was on the pillion perch. Once I had a bungee cord snap, wrap around the rear wheel whilst my clothes were scattered half a mile down the road. I never knew that bungee cords could be stretched so thin.
Touring the bike could manage, but only 150 to 200 miles a day. Any more then it became very uncomfortable and somewhat enervating (from the vibes and revvy nature of the engine). Fuel, engine maintenance and chain wear were other variables that didn't inspire during long distance usage but the basic reliability of the engine meant I had every confidence in reaching my destination.
Some Benelli motors don't last very long (I've just brought a dead 504 with only 14000 on the clock) but mine has now done 33000 miles without any major problems except for frequent doses of tender loving care. I suspect that is the determining factor in durability, neglected bikes both rusting and seizing quicker than most. Spares are so rare that it pays to track down one of the non-runners. Rarity of the 504 makes that hard work.
Prices are hard to work out. There's always the odd jerk who thinks because it's rare and Italian it must be a classic worth thousands, but I bought my nice one for £450 and the non-runner for £95. That sounds about right for a machine that's slow, quick corrode and heavy on consumables. I like its looks but can't claim it approaches beauty. It runs well in town, for short blasts in the country and for moderate touring. As a cheap and cheerful all-rounder it makes the grade, as a future classic my money's on the CB500/4!
H.K.L.