Classic Motorcycle Mechanics

Jim Lindsay rides Honda’s maligned V4.

What is it about the muchmalign­ed early eighties V4 Hondas that seems to endure? Jim Lindsay finds the answers.

- WORDS: JIM LINDSAY PHOTOS: GARY D CHAPMAN, JIM LINDSAY, MORTONS ARCHIVE

y regular transport for the past two months has been the 1985 Honda VF750F tested here. It was not meant to be that way, but the cosmic foot stamped heavily on my choc ice. With just 17,500 miles on the clock my daily transport, a 2013 KTM RC8 R, snapped an inlet valve. I’d just got the VF through its first MOT in heaven knows how many years, so I thought I may as well put it to work as a stand-in for the self-disembowel­ling V-twin from Austria. Although I’d rather not be shelling out small fortunes on the parts to fix my modern scoot, I have been amazed (and delighted) at what an excellent day-to-day bike the 32-year-old Honda V4 makes. It starts first time every time, returns about 45mpg until you start to cane it, and draws attention wherever you go. One of my most enjoyable journeys was a 200 mile autumnal round trip to the Classic Motorcycle Mechanics show at the Stafford showground. The day started out grey and wet, but not too cold. The brakes were okay in the wet, the Bridgeston­e BT45 tyres gripped well on the slippery Tarmac while the frame mounted cockpit fairing kept most of the rain away from my body. I was spotted by one of the organisers as I pulled into the bike park and before I had time to dig the side-stand puck out of my luggage, I had been invited to ride the bike in the parade later that day. “What, this old thing?” I asked, half seriously but inside, I felt a small glow. I did my duty in the Stafford parade ring. In front of the audience, editor Bertie Simmonds asked why I was dressed like a schoolteac­her (I’ll get you for that Simmonds). I caught up with some old mates, bought a massive lock and chain, and had a fascinatin­g chat with exceptiona­lly talented CMM contributo­r Allen Millyard. A great day out rounded off with a trip home in the recently arrived sunshine, and a chance to whizz along a collection of sparsely populated A-roads, dealing confidentl­y with the traffic to keep my rate of progress respectabl­e. It’s comfortabl­e too. I reached home with that buzz of adrenalin that you get from a brisk ride, but none of my body parts were protesting. It’s fun and practical then. So let’s take a closer look. The VF750F arrived in the UK in 1983. Until then, the 750cc class was dominated by inline four-cylinder air-cooled four-strokes. Some still sported twin rear suspension units.

They had one thing in common. When the VF arrived, it made them all look years out of date (and they were). It was a radical departure, just the sort of thing you would expect from Honda. We had already seen the engine in the shaft-driven VF750S launched in 1982 but while we liked the power, it deserved a better frame and a more appealing set of clothes. The bike on test here is a 1985 USA market model, the VF700F, which was imported into the UK in 1995 and which has had a late model 750 engine fitted. The 700cc bikes were made to get around the import tariffs on bike bikes imposed by the US government (see separate story) Although The VF’S V4 engine suffered from camshaft problems which eventually caused its early axing from production, a well sorted one is a joy to use. It’s flexible as you like. It will burble along in top (fifth) gear at 30mph and pull away cleanly from there without needing a downshift. At the other end of the scale, if you thrash it to the 10,500rpm red line it can whizz up to exceptiona­lly wrong speeds accompanie­d by delicious V-shaped howls from the induction roar and the exhausts and no discernibl­e power band. In top gear, 70mph comes up at a modest 5250rpm. There is a steady, low frequency vibration at this speed. It is not severe enough to be a problem. The engine is at its sweetest between 7000 and 8000rpm. By then you are significan­tly above the UK’S highest limit in top gear, so it’s just as well the mirrors give a blur-free view of pursuing enforcemen­t vehicles. When the bike first came out, Honda claimed 90bhp at the crankshaft. In the real world, on a dynamomete­r, it made 70bhp at 10,000rpm, measured at the rear wheel. It made a bit more power than other 750s of the day. This advantage was partly cancelled out by the additional weight of the engine, arising both from its configurat­ion and the use of liquid cooling. At 220kg (484lb) it was a bit heavier than the air-cooled, inline four cylinder competitio­n. Well sorted aerodynami­cs helped it to a higher top speed than anyone expected at the time. While the air-cooled opposition struggled to break into the 120s, all the road testers of the time managed to drive the Honda comfortabl­y into the 130s. I recorded 137.94mph at MIRA on the one I tested (see separate story). It ran the standing start quarter mile in 11.67 seconds with a terminal speed of 113.69mph. It was quick alright. In the Daytona Superbike race that year, Freddie Spencer took the win on his VF with the V4s of Mike Baldwin and Dave Aldana claiming second and third respective­ly. Back then, it laughed at modern traffic, leaving lines of cars in its wake. Nowadays, with more and faster traffic, you can still make decent progress but you need to buzz it towards the red-line to make safe overtakes on two-lane roads. The gearbox on our test bike was okay on upshifts but a bit sticky on the downshifts. I suspect a weak return spring in the selector mechanism. To be fair, the shift was not that great when the bike was brand new. It has a slipper clutch, a first for a production motorcycle in 1983. It works okay too, avoiding rear-end lock ups when you start to get enthusiast­ic on the tight back roads. However, this was perhaps a modificati­on aimed at the racing world of the time. To get it to work on the road, which I managed a few times, you have to downshift with the mechanical sympathy of a polar bear – ‘a bit cruel on an old bike,’ I thought, before deciding not to try it again. The front forks split rebound control and air preload into separate legs, rebound on the right, air on the left. The air is balanced across the legs by a pipe connecting the two and hooked up to air seals which secure the joint between the stanchions and the top yoke. The VF was produced before the days of cartridge forks and tunable compressio­n damping. What we had then were various forms of anti-dive control which attempted, with differing levels of success, to slow down compressio­n under braking. Honda’s take on this was TRAC, which stands for Torque Reactive Anti-dive Control. It works like this: the left-hand front brake caliper is attached by a pivoting mount at the top while the bottom caliper mounting fastens to a bracket connected to a plunger in the anti-dive control. When you apply the front brake, the caliper rotates in the direction of the wheel travel, pulling the plunger out and activating

“The VF’S V4 engine suffered from camshaft problems, but a well-sorted one is a joy to use. It’s flexible and will burble along in top at 30mph!”

a mechanism which restricts the flow of damping oil inside the fork leg to slow down the rate of compressio­n. A hefty cast aluminium alloy brace bolted to the sliders ensure that the rebound damping forces, available only on the right leg, and the anti-dive forces, available only on the left-hand leg, are distribute­d evenly across the front suspension. Jolly clever eh? Well, not entirely. Now as then it’s hard to tell any real difference between the three rebound settings; the air pressure, variable between 0 and 6psi does not noticeably alter the behaviour of the front-end. On the plus side though, the anti-dive mechanism does work quite well, and helps when braking late and hard for corners. The rear suspension unit is adjustable for rebound and preload and – like the front – is controlled by air pressure. Changing the rebound settings seemed to make little difference so I left it on number three of the four positions. Air pressure is topped up via a Schrader valve on the end of a tube which lurks behind the left-hand side panel. Recommende­d pressure is 7-43psi. Even at maximum, it was too softly sprung at the rear, but that’s how they were back then, which is probably preferable to the Italian ‘the harder the better’ approach of the time, often tricking you into thinking that someone had bolted the base of your spine directly to the chassis. If you want to get serious about improving the handling, a modern rear unit would help a lot, as would some serious attention to the front forks. Despite these shortcomin­gs, the Honda handles well enough to keep more up-to-date bikes honest on twisty roads. It turns in quickly. The fashionabl­e at the time 16in front wheel helps here. The front-end is stable enough to let you trail brake into corners if you feel the urge. It holds the line well driving hard out of bends. It does wallow a bit in long, fast curves. Dialling in more power does not help in this situation but the weaving stops a long way short of being scary. Tyre pressures proved critical. They need to be at the originally specified 32psi front and rear. Even a few pounds more and the handling starts to feel vague in slow corners and the tendency to weave is magnified in fast corners. In a straight line it is stable all the way through to the top speed. I was pleased with the Bridgeston­e BT45S. They gave excellent grip, wet or dry, and on two occasions when I was being stupid, their behaviour while sliding saved my sorry carcass. The brakes also work well. They have enough power and feedback to keep you confident and safe. Both front and rear are twin-piston, sliding caliper units. They do not have the outright power of opposed piston calipers, but provided you keep the pins on which they slide clean and properly lubricated, they are fine. The chassis is fashioned from square tubing, more correctly known as RHS (rectangula­r hollow section). RHS tubing, in both steel and aluminium alloy, was becoming popular for racing frames in the 1980s. It had the advantage of maintainin­g its strength when bent in multiple planes without the need for the additional bracing that would be required with round tube. Fashion and function were hand-in-hand with the VF chassis, and it was the start of a trend that would be widely adopted for road bikes over the next few years. Honda used steel RHS tube as did Yamaha for its 1985 FZ750. Suzuki went one better, using aluminium alloy RHS on its mould-

breaking GSX-R750. In common with many Hondas of the period, the VF runs Comstar wheels. The Comstar consists of an aluminium alloy rim attached to the hub by either aluminium alloy or steel spokes, depending on the model. The VF uses aluminium alloy spokes. The thinking behind the Comstar was that it gave the flex and feel of a spoked wheel while offering the strength of a cast wheel. It was not a design that survived: it became a victim of advancing technology, fashion and the need to keep manufactur­ing costs under control. In their anodised gold finish, the wheels on the VF look great, the only drawback being that they are utter sods to clean. The Honda is an easy bike to live with. Maintenanc­e is straightfo­rward. Most stuff is easy to get at but you do have to remove the radiators to get at the front pair of cylinders for valve clearance adjustment. Getting the cam-cover off the rear bank is also quite a fiddle. And finally, 35 years on from its first appearance, it looks absolutely ace. The lines flow sweetly. It is a timeless design. Finding one is not so easy. With a short production life (1983 to 1985) and a spoilt reputation due to the early problems with the camshafts, not many VFS survived and even fewer have been well cared for. They are about as hard to find as a GSX-R slabby or an original FZ. Prices vary widely. Top asking price is around the £4000 mark, although I do not know if those prices are being achieved. You get the occasional decent one for a couple of thousand. I picked this one up complete but needing work with another in bits for under a grand: lucky me! I neither know nor care if it will become a valuable classic. What I can say is that it’s a delightful, usable bike which combines classic appeal with everyday practicali­ty and that will do for me. cmm

 ??  ?? Once maligned and now mighty: the VF750, not our Jim!
Once maligned and now mighty: the VF750, not our Jim!
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 ??  ?? Initially troubled but later triumphant motor and layout.
Initially troubled but later triumphant motor and layout.

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