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This page :-An article written for the FF Club by Eddie McDonnell.
Next page : Continuation of Eddie’s text plus Monty’s reply
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I finished it and sent it to MCS&L the other day, as last month Andy Stephenson promised to tell us all about what's wrong with FF's in this month's (November 1998) edition, without actually having ridden one, as far as I can tell. Like you, I'm not interested in trying to convince these people if they don't want to know, but since I had it in hand and at least MCS&L shows an interest I sent it to them the other day and have promised it on disc to the FF Club Mag.
Riding FFI want to talk about the fundamentals of FF riding -how we handle them. I think there's more needs discussing about this than about metal working and design problems, development and construction. I've a few observations to make about how we go into turns, corner, use steering and body weight; and how what we do is affected by the riding position and the lowered centre of gravity (C-of-G). Also, to describe instead my FF engineering experience would only revive memories of the monstrous amounts of mental pain and effort invested in building and developing the thing that I'd much rather forget about! My observations on riding do however lead to conclusions about design issues on riding position, C-of-G and wheelbase, key features of FF design and layout.
I'd better give some mechanical information. Mine is a Moto Guzzi V50 Mark 2, modified by Malcolm Newell for John Golden in 1982 to make what John Bruce says was the first Phasar after the original Quasar ceased production. I rebuilt it 1990 to 1994, and made it open top, much to the dismay of John G and some of Malcolm's team ! It's pretty much standard wheelbase -Malcolm's addition of Bob Tait Hub Centre Steering (HCS) added only about an inch. And although I've recently fitted a longer swinging arm, it's only the standard fitting on the current V50-originated 750's, adding just 48 mm. So my wheelbase is 1482 mm / 58.3". Seat height is currently just under 18". This and the short-by-FF-standards wheelbase explains why I have the experience to comment as I will on quick steering !
With four years experience of continuous use and developing it through some handling faults, I've tested out different techniques of riding and worked out some observations of how we ride FF's compared to conventional bikes. I've also ridden my FF's twin, Pete Billington's Guzzi, and ridden his VT 500 White Shark three times. Why doesn't somebody go and buy this exciting bike off him for what's not a great amount for a working FF with a pedigree? It's currently going to waste. Since my other bike is a conventional V50 I've had the opportunity to get straight off one and onto the other, and since I've also ridden each for many laps of Oulton Park on a couple of track days, I have the rare experience of having made a direct comparison of conventional v FF riding position on otherwise identical bikes. Well, there is the Hub Centre Steering too.
I use the FF day in, day out round Manchester and up and down the country, wherever. Four years continually on the road. This is a reliable working bike. It works. I really wanted to ride it on the Isle of Man, and duly did so visiting this year's Manx Grand Prix. It works there too.
I'm writing for FF'ers, who I know will be interested. Others can read and reflect if they want, but I'm not very interested in confrontational debate about the merits of FF's with other people who aren't convinced about them. I've got mine, why bother about them ? I know many of them are happy enough anyway with what they've got, so let's not get in a sweat about it.
HandlingThe handling faults I had to sort were all traced to pretty conventional things - if that includes setting up a double wishbone Hub Centre Steering (HCS) front end, and wheel alignment both vertical as well as lateral, along with shocks and bearings. But conventional in the sense of being mechanical rather than riding-position related. It didn't handle that badly, even a few weeks after being first put on the road I was faster round Oulton than on the conventional bike, and as fast or faster round the corners as many of the modern race-reps that were there. Now there's four year's development been done and it's pretty well sorted.
In analysing steering actions, I'm working on what Tony Foale says, that we steer by a combination of counter-steering and shifting body weight to push the bike down. We subsequently use body weight differently, to move the C-of-G- G to the inside to reduce the angle of lean necessary. I've also read John Robinson's books but I won't pretend to understand the equations! I'm happy working from Tony Foale's concepts, but I'm open to being told I've overlooked some fundamental of physics or riding. I find many people both for and against FF's get basic things quite wrong, so you might tell me that I have.
Straight Line RidingI had a problem of 'skitter' whereby at town speeds the bike felt unplanted and a bit wandery when encountering bumps - external forces. This really turned out to be over-stiff rear suspension and stiff rose joints in the front steering. But before sorting them out, I experimented with moving my weight about. I found sitting up off the backrest has a dramatic effect – it feels more stable and more like a conventional bike. What happens is that I immediately start moving my weight slightly to correct each minor weave or wander, whereas sat back my weight is static. Also, sat up, more weight goes down onto the bars, so I feel the front wheel pattering over bumps, which feels more informative although not essential, I think. I suppose the fast boys and girls will say it helps you to sense when you're on the limit of tyre adhesion.
Sat up, my upper body weight is a little too unanchored to ride like that since my legs aren't straddling the bike and not planted downwards onto the footpegs, like on a conventional set up. So at one period I ran with my backrest propped more upright. I noticed a photo of Graham Fryer on a race track with a makeshift upright backrest, I assume for the same reason. Interesting. But with the bike properly set up, it's not at all necessary to sit up for normal riding. Another discovery, was that settled against the backrest it is possible to sit down with your weight off-centre to the bike, which I sort by momentarily bracing my weight between the footrests and the backrest, then sitting down again with my weight self-centred on the bike. Or I can just lift my back off the backrest and feel for the most balanced sideways position in which to re-settle my weight. Conclusion - when using a backrest, centralising your body weight might help the feel of the handling. And an adjustable backrest will enable you to choose on occasion to sit upright instead of laid back.
Steering and CorneringFor a while, I had a weave through long fast curves that produced a slow waggle on the bars. Fitting the longer swinging arm complete with new Konis and then sorting out the spring rate has removed that bit of fun from my riding. Whilst getting the mechanical solution together, I tried some more riding techniques to counter the weave.
First, I fitted pads high on the sides of the dummy tank to enable me to grip the bike with my knees. It didn't do anything about the weave as such, but I got a much better feel for initiating turns and also in altering line and lean angle voluntarily in mid-turn. However, it wasn't comfortable to pull my knees into the pads from the splayed out position dictated by the back of the dummy tank, so I didn't use them much and have now removed them. But more later on this angle.
From trying my best round the TT - on conventional bikes - I'd found that foot pressure was very handy for fine-lining it through all those linked bends where line and position are so important. Monty (Pete Billington), who is largely to blame for me going FF, wouldn't have foot pressure as a way of doing things, saying it's all counter-steering. Try it, though, and it does work. Kenny Roberts recommends it, and you've got to listen to what he says. But, the more I pay attention to what's happening when I use my feet, it seems what I'm really doing is bracing my body to make a very finely controlled counter-steering action.
Do it on a conventional bike, and your foot to hand action is damped through working through the mass of the body and the muscles of the torso. Also on a conventional bike, the foot pressure probably also enables shifts in body weight. Try it. On my FF, my weight is placed on the backrest, so I'll not be shifting body-weight much. And any foot pressure is forward not down and so there's little shifting of body weight or damped counter-steering available that way. I'm also not getting the clamping of the lower body onto the bike with the upper leg or knees onto the tank that you get on a conventional bike, which together with foot pressure enables really fine weight movement and damped counter-steering.
So, on my FF, it's almost all counter-steering to go into a turn and to alter line and angle in the turn. Now although FF's are pure joy to do this with, being so quick to turn and bank, I find mine a bit too sudden when I'm really trying. That is, when going fast and banked over in a corner, applying more counter-steer takes us further over more suddenly than I want, and I might then have to bring it up again. I'm counter-steering only, from the mass of my body just planted on the seat but not gripping the bike or braced on it. It can be too much and too quick for what I want.
Now I normally sit with my bum back in the seat. I ride in town a lot, and from that position I can more easily put my feet down and also turn my head to the right when joining other roads at angled junctions. But I've got a few inches of fore and aft movement available. Just before leaving the Island recently, I tried shoving my bum forward so my pelvis and the back of my upper legs were firmly up against the back and side of the dummy tank. Instantly, I felt both more stable and yet more relaxed in a straight line riding. More like I remember Monty's Guzzi FF which is more laid back and more naturally like this than mine. With my back against the backrest and pelvis located more positively, this is was what I was after with the knee-pads. In turns, I can counter-steer far more deliberately. I notice one of the superscooters has a pommel at the front of the seat which provides a similar location point.
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