It was a bit of a shock to the system to find myself buying a bike I'd bought ten years before! Even back then, the CB400N had done over 30,000 miles and was well on the way to dying from the built-in obsolescence - or so I thought. With 69,745 miles on the clock (probably some miles missing from broken speedo cables as there was a batch that was a fraction too short and therefore short-lived) it was surely ready for the nearest canal or scrappie...
Apparently not. The front forks were off a GS450, the shocks were Koni's finest, all the chassis bearings were new and barely a speck of rust poked through the repainted (in bright yellow!) chassis. The engine shuddered, clacked away and suddenly burst into life. The downpipes were original, coated in several layers of heat-resistant matt black paint; the silencers were off some old BSA twin - as in very loud. I figured they were there to cover the noise of the disintegrating balancer chain and stuck camchain.
To be honest, I couldn't make out any engine noises, but I've always been a bit of a pessimist - from bitter past experience. The 400 Superdream's always been a bit underrated, having enough power to see off the majority of cars, and when in good shape cruise along at the ton, even though top speed's only 110mph. In many ways all the motorcycle that's needed on UK roads. The test ride revealed that most of the power was there and that handling and braking were up to spec. Try as I might, couldn't find anything wrong with the machine save for its high mileage. Decided to take a chance, handed over 500 quid.
The 25 mile ride home went pleasantly enough. The shock came the next morning when I went to check the sump. The oil was way below the minimum level. I cursed away, as you do, got the bicycle out to hit on the local car accessory store for a five litre can. Getting the sump bolt out was the usual hassle with rounded nut edges and bruised knuckles but mole-grips and a very big hammer eventually did the trick. New oil, a sharp eye kept on consumption - about half a litre a day but it didn't seem to be burning any off, and leakage was confined to a slight smear around the cylinder head gasket. Fresh oil patches on the drive...
Rooting around I found that the engine breather had been reworked so that it exited at the back of the bike rather than into the airfilter. Soon as she was revved above five grand, a heavy mist of oil fumes started spurting out. Time to burst into tears. The rest of the day was spent tearing off the cylinder head and barrel, the latter corrosion-welded into the crankcase!
Apparently not. The front forks were off a GS450, the shocks were Koni's finest, all the chassis bearings were new and barely a speck of rust poked through the repainted (in bright yellow!) chassis. The engine shuddered, clacked away and suddenly burst into life. The downpipes were original, coated in several layers of heat-resistant matt black paint; the silencers were off some old BSA twin - as in very loud. I figured they were there to cover the noise of the disintegrating balancer chain and stuck camchain.
To be honest, I couldn't make out any engine noises, but I've always been a bit of a pessimist - from bitter past experience. The 400 Superdream's always been a bit underrated, having enough power to see off the majority of cars, and when in good shape cruise along at the ton, even though top speed's only 110mph. In many ways all the motorcycle that's needed on UK roads. The test ride revealed that most of the power was there and that handling and braking were up to spec. Try as I might, couldn't find anything wrong with the machine save for its high mileage. Decided to take a chance, handed over 500 quid.
The 25 mile ride home went pleasantly enough. The shock came the next morning when I went to check the sump. The oil was way below the minimum level. I cursed away, as you do, got the bicycle out to hit on the local car accessory store for a five litre can. Getting the sump bolt out was the usual hassle with rounded nut edges and bruised knuckles but mole-grips and a very big hammer eventually did the trick. New oil, a sharp eye kept on consumption - about half a litre a day but it didn't seem to be burning any off, and leakage was confined to a slight smear around the cylinder head gasket. Fresh oil patches on the drive...
Rooting around I found that the engine breather had been reworked so that it exited at the back of the bike rather than into the airfilter. Soon as she was revved above five grand, a heavy mist of oil fumes started spurting out. Time to burst into tears. The rest of the day was spent tearing off the cylinder head and barrel, the latter corrosion-welded into the crankcase!
The good news was that the valves, rockers, camchain and tensioner all looked newish. The bad news was a pair of worn out oil rings. The local breaker had a box full of Superdream bits, take my pick - a quid the pair! I also bought a newer head gasket for the same money. He had three rotten looking engines on offer but wouldn't let me hear them running - only fifty quid, so I expected the worst... on old Superdreams that means absolutely everything worn out!
The motor went back together with just the right amount of gasket goo to ensure oil leaks were a thing of the past. If you're used to working on Jap engines, it's a relatively easy deal - as the top end had obviously been worked on recently I didn't have any hassles from corroded in bolts, and the like. The engine cases were already fastened down with allen bolts instead of the cheesy stock screws. I whipped them off to check the balancer over, only to find someone had already removed the whole gubbins - explaining the relatively heavy vibes at 80-95mph. Wasn't death city, would still fade into the background after a while.
Back on the road, the Dream roared along like some demonic steam-roller, causing dogs and peds to go mental, more than one cager trying to ram me off the road. As the airfilter was also missing, someone had gone to the extreme lengths of rejetting the carbs - the power delivery was surprisingly free of holes, though the exhaust ran so hot it took less than a day for all the matt black paint to fall off and rust proliferate at a mad rate!
Didn't make any difference to the performance until it started banging on the overrun. Air leakage out of the downpipe and silencer joint (the collector box was nowhere to be seen, extra metal welded over the downpipes where it was supposed to connect up). Pumped it full of Gum-gum; a twice monthly chore but necessary as the detonations were like a bomb going off and not a good idea in paranoid Central London! Even the cops were jumpy in the wake of the nail bomb attacks.
Performance was what you'd expect from an aged Superdream, able to top the ton with a following wind and reasonable rates of acceleration up to about 80mph (the speedo was so worn that it wavered 5mph either side of the actual reading). The wear really showed up in the fuel economy, 35-40mpg! Even with the newer oil rings the sump still needed topping up every couple of days and every 100 miles if it was thrashed flat out.
The handling was pretty good, no complaints, but that was because none of the suspension was stock and all the chassis bearings were newish. A typically aged Superdream tends to fall into fast corners, weave around alarmingly and speed wobble at speeds in excess of the ton (most that have worn their suspension so deeply have also done in the motor, such death throes thus rare).
The braking was up to the speed but a bit vague. Again, the front end wasn't stock so complaining or praising it is relatively meaningless. Calipers and discs go pretty nasty after the first 30,000 miles on stock Superdreams, thereafter often failing when they are desperately needed! This actually helps with the engines of those left on the road, as many ended up as a cheap source of spares in breakers!
After about four months and 6000 miles I again decided the CB was on its last legs, sold it for 600 notes. The new owner is still running the damn thing, waves every time he comes past my house! Irritating! I just bought another running Superdream for a hundred quid, needs lots of replacement chassis bits but the engine burbles away like a good 'un. Well, sort of!
James Grathton