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This page :- Continuation of article written for the FF Club by Eddie McDonnell.
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Also, lodged against the dummy tank, I can lay it over more by pulling down on the dummy tank with the inside of my outside thigh, as you do on one of those conventional 'what are you doing up there?' bikes that you see around. I'll get more of this if I make a more substantial dummy tank, shaped like current GP and Superbike tanks. It gives me still more of the 'anchoring' effect and I can hang off a little too. I feel like I'm banking by pulling on the dummy tank rather than counter-steering, with a more manageable 'heavier' feel to it. I may in fact be just counter-steering from the more anchored position. In any case I can increase the banking angle in a more measured and damped way than counter-steering from a sitting-on, unclamped seating position.
Tony Foale referred also to using downward pressure on the bars to turn. I've done that on my conventional bike, pressing down or pulling up to turn for the same reasons as using foot pressure, for fine-lining. The pressure on the bars may be a body weight effect, and/or it could be the tilt rather than turn effect on the front wheel gyroscope. Or neither. Maybe it's counter-steering again, damped to a finely-adjusted degree by acting through the rake angle of the bars, which turns the vertical pressure into rotation of the bars, and counter-steer? What is happening when, moto-cross style, we keep the body upright while the bike banks, whilst pushing down on the inside bar?
Try it. Anyway, on my FF, my hand to elbow line is pretty much horizontal and so this kind of pressure is not readily available, unless I can get my shoulders higher or the bars lower.
Centre of GravityOf course, the main reason for the quick steering is the lowered C-of-G. As I write (October 98), I'm expecting Andy Stephenson is about to help us out in Motor Cycle Sport etc. by pointing out that it's not all gain. Well of course. Using my BSA A10 with a heavily loaded tank bag 25 years ago, I noticed that weight high up can actually feel better and Honda claimed as much with the CX500 in 1979. It's an agility v stability compromise. The higher C-of-G of conventional bikes provides greater damping inertia against roll when outside forces like bumps and wind try to tilt the bike, and so helps keep the bike upright. But it also makes it more of an effort for the bike or rider to correct any movement that does occur. And makes it more difficult to bank into turns. With our low C-of-G we're more easily deflected but at the same time more easily corrected either through the bikes self-steering geometry or rider input. And, we're able to bank over quicker and with less effort. We do have to bank a little more f running fat tyres, than a conventional bike.
ConclusionsI mentioned my bikes' short wheelbase, compared to other FF's. Blezard was disappointed it wasn't longer when he briefly tried it. I've not ridden a long wheelbase FF - I had to come home from the Manx on the day I'd arranged to try Mo Simpson's original Quasar at Laxey. I suppose that as well as accommodating passengers better, a long wheelbase damps out the quick steering derived from low C-of-G ? The point is, any FF has a whole new set of compromises of key factors like trail, wheelbase, riding position and C-of-G which have to be worked out in design and development.
I'm going to try going back up a bit with my C-of-G, to see how else I can develop the cornering ability. I find I notice changes in the handling from quite slight changes in seat height as I use different seating. I expect going up three or four inches to around 22" might give me a heavier cornering action, that I might like.
Having said it's a new compromise and bearing in mind what I've said about riding position and C-of-G, it can easily be a matter of a moment's choice. All we really need is decent seating that enables quick up and down adjustment of seat height, and backrest angle. Easily done if some engineering company were to set their designers to it. For me, let's see what Halford's have got in the way of scissor jacks to fit under my seat. Or a lightweight hydraulic jack ? Or what about those office chair gas-cartridge mechanisms? Maybe just a removable thick squab ? Or forget it for now, it's fine and dandy, leave it alone !
FinallyFF's are not just more comfortable, they're more FUN ! I thought most people wanted quick steering ? Andy Stevenson in Motor Cycle Sport wants us to prove to him that FF's are better. I'll leave that up to him as he seems to want to know. I know already for myself, so please yourself Andy, and thanks for the advice on Hub Centre Steering. Even if neither Ash nor Stevenson in rubbishing FF's haven't mentioned any experience of riding them, at least MCS&L show an interest. FF's won't get into MCN and the rest unless we give them 'sexy' bits, which I find confusing as from my experience of riding bikes and sex they're quite different, although both fun.
Without caring whether FF's are better than conventional bikes for racing or not - I mean there's not much we could do to shift weight for and aft for traction is there - it would be interesting to see someone racing an FF with a decent motor, just for the crack. But do the ACU apply the FIM's anti-dustbin rules, which I believe ban feet being forward of hands, therefore banning FF's? Would they alter or make exception - maybe MCS&L could find out about it for someone to try it ? I would if I won the Lottery. Mind you, I don't do the lottery...............
Feet Up Eddie McDonnell |
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Monty’s reply
His comments about my wee beastie make interesting reading to me. Here are my comments on my V50 Phasar.
Front monoshock is off a scooter is not adjustable and has been on since the bike was converted by Malcolm decades ago.
I have never adjusted the rake or trail settings, all I did was make sure it had no bump steer before I fitted the front shock. I have the top pivot pulled back in as far as it will go to give the most trail the system will allow.
The rear shocks are the original crappy Guzzi ones from the original T reg donor bike, God knows if there is any oil in them.
From the above it should be awful to ride but it is in fact superb, the real laid back position and feet right up front with the arms parallel to the legs and only a couple of inches away means it is impossible to get thrown around or use weight to manoeuvre the beastie, you are well and truly glued to the backrest. There is no sitting up straight allowed on this machine and none is needed. Low speed down to almost a stand still is no problem, I use the steering to effectively move the front wheel contact point from side to side compared to the C of G to control the balance.
Key detail :- The handle bars are only 20" across, there is only just enough room to fit the controls onto the handlebars, the indicator / light controls almost meet in the middle.
Even though the narrow handlebars would make you think the steering would be hard work in fact it is exceptionally easy, I only really rest my hands on the bars and let my arms dangle but a quick counter steer nudge is all that is needed to execute even the most violent manoeuvres. It is amazingly nimble but is also rock solid at the same time, sounds like a contradiction for a 'normal' bike but is true.
Since I first rode Eddie’s V50, when I didn’t particularly like the way it handled, he has increased the trail to as far as it will go on his machine. I rode it again after that and it was a huge improvement. Since we compared handlebar widths Eddie has started holding the bars with his hands a lot closer together to simulate my handlebar width, he has since reported that this is a further improvement.
Don’t ask me to explain any of the above, the ‘feel’ and ‘handling’ of a 2 wheel vehicle are very strange.
Monty, April 99
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