I had only just bought the 1999 Yamaha Virago XV535 when it began introducing itself properly. It had passed its MOT, looked sound and had covered only about 80 miles during the previous year. At the time, I regarded that low mileage as reassuring.
The first warning came at Bromyard, where I filled the tank for the first time after buying it.
There was no petrol leak that I could see. Instead, almost immediately after filling, the bike began popping, misfiring and operating at roughly half power. It felt as though one cylinder had decided to become an occasional contributor rather than a full member of the team.
Because the trouble began immediately after filling the tank, the filling itself became the obvious suspect. Perhaps I had brimmed it too enthusiastically. Perhaps excess petrol had found its way somewhere it should not. Perhaps filling the tank had disturbed some contamination lying quietly at the bottom. At that stage, all I knew was that the bike had been running properly, I had filled it with petrol, and it had immediately begun behaving like an asthmatic lawnmower.
The bike would still run, so I carried on to home, following Hay who was driving the motorhome..
After about 15 miles, the popping and misfiring disappeared and the bike appeared to be running normally again on both cylinders. By the time I reached the M5, it had recovered its full power. I could still hear what sounded like backfiring, which was not encouraging. Then I moved my head down and the noise disappeared.
The position of my head could not possibly affect a backfire, so I began moving it around deliberately. Head up: popping. Head down: silence. The engine had not developed a posture-sensitive ignition fault. The loose strap from my helmet was flapping against the skid lid.
That was reassuring, but also slightly misleading. The motorcycle genuinely had recovered its full power, and the remaining apparent symptom had turned out not to be mechanical at all. It therefore seemed perfectly reasonable to conclude that whatever had happened after filling the tank in Bromyard had worked its way through and cleared itself.
That was the comforting interpretation.
45 miles further on and back home, No. 2 Son took it out for a ride. When he returned, he said it had been cutting out. I immediately noticed petrol leaking from the right-hand side of the bike, but only while the engine was running.
That changed the nature of the problem.
The fact that it appeared only while the engine was running suggested that the active fuel supply was involved, rather than petrol simply draining continuously under gravity.
At first, the source was not obvious. Petrol was appearing around the decorative air-filter housing on the right-hand side, but on an old motorcycle the place where liquid becomes visible is not necessarily where the fault began. Petrol runs along pipes, castings and brackets before eventually dripping from whichever point happens to be lowest.
The answer came from following the hose rather than continuing to theorise about it. The hose ran across the bike to the rear carburettor. It was not a conventional overflow pipe hanging safely beneath the machine. It was the carburettor breather routed into the right-hand dummy air-filter housing, directly above a hot cylinder head.
A breather is supposed to carry air. It is not supposed to pour petrol onto one of the hottest parts of the engine.
That meant the fuel level inside the rear carburettor was rising far above where it should have been and entering the vent passage. The likely cause was a sticking float, dirt beneath the float needle, wear in the needle or seat, or some combination of old petrol deposits and contamination from the tank.
Suddenly, the trouble at Bromyard made rather more sense. The popping, misfiring and half power may not have been an unrelated episode caused by overfilling. It may have been the first indication that the rear carburettor was flooding and overfuelling one cylinder. After 20 miles, the fault may have temporarily cleared, allowing the engine to run normally again.
It had not repaired itself. It had merely become intermittent.
This is one of the traps with old machinery. When a symptom disappears, we are inclined to treat the problem as solved. The engine stops misfiring, the warning light goes out or the strange noise vanishes, and we decide the machine has recovered.
Machines do not recover. They either continue to malfunction or wait until a less convenient moment to demonstrate that the fault is still present.
I tried the simple remedy first. Tapping the carburettor bowl did not free the suspected float valve. One float-bowl drain also appeared blocked, strengthening the suspicion that old fuel deposits, or possibly rust from the tank, had contaminated the carburettor.
None of this should have been entirely unexpected. For a 27-year-old motorcycle that had covered only about 80 miles in the previous year, it was a problem waiting to happen. That is not really use. It is occasional proof of life.
The MOT showed that the bike met the test requirements on the day, but an MOT is not a mechanical health certificate and never has been. It cannot establish how an ageing fuel system will respond when the tank is filled and the motorcycle is suddenly asked to cover real mileage again.
Like many people, I instinctively equated low mileage with good condition. What this episode reminded me is that machines do not simply wear out through use. They also deteriorate through inactivity.
A motorcycle ridden every weekend may be healthier than one that has spent years sitting quietly in a garage. Regular use keeps fuel moving, valves operating, seals wetted and passages clear. Standing preserves the odometer. It does not necessarily preserve the machine.
In hindsight, the bike was not failing. It was introducing itself. The important point is that the fault has appeared now. Thank God it happened at home rather than on another long journey. A leaking carburettor on the drive is an inconvenience. The same fault miles from home, with petrol escaping above a hot cylinder head, becomes a recovery problem at best and a fire risk at worst.
Fortunately, the remedy is neither mysterious nor ruinous.
There is a workshop experienced with older carburetted Yamahas only a couple of miles away. A mechanic accustomed to rebuilding banks of 4 Mikuni carburettors on Yamaha FJs is unlikely to be frightened by the Virago’s pair. The sensible course is a proper carburettor rebuild, inspection of the tank and fuel supply, replacement of any worn needles or seals, and possibly a tank flush before the carburettors are balanced and the bike returned to service.
The anticipated cost is somewhere around £250 to £400, depending on what parts are required and whether the tank needs attention. For a motorcycle bought for £1,750, that is entirely acceptable. It is not a catastrophe that suddenly makes the purchase uneconomic. It is a reasonable recommissioning cost on a 27-year-old machine that has spent too long doing almost nothing.
Nor is there any value in disguising the fault. Extending the breather hose would merely arrange for the petrol to leak somewhere less visible. That is the mechanical equivalent of moving the bucket rather than repairing the roof.
Once the carburettors have been properly cleaned, rebuilt and set up, and any contamination in the tank has been dealt with, there is every reason to expect years of happy riding.
Buying a classic or modern classic motorcycle is not like buying a new appliance. You do not simply acquire an object; you begin a relationship with a machine that has accumulated its own history, habits and weaknesses.
The purchase price buys the motorcycle. The first proper journey starts the conversation. The Virago had passed its MOT. What it had not yet passed was its first full tank, its first proper run and its first opportunity to reveal what 27 years of age and 80 miles a year had been quietly storing up.
I should be back on the road within a week.












