Featherbed frames

Jack Forrest used to be a works rider for BMW. I once watched him win an Allpowers race at Bathurst with a 650 SS. He beat all the Manx Nortons, but he was an exceptional rider. It was in about 1963. My mate hated Jack's guts because he had a big mouth, and my mate did not beat him. It was just before the two-strokes arrived. They ended that game.
That video of the Manx Nortons at Brands Hatch - can you imagine that on a big circuit like Bathurst ? Even at Phillip Island they were great. I think those races at Goodwood suit them.

Mike40M said:

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On the unconventional frame tubes to steering head setup. The head steady part from top of the steering head to the cross tube is important for strength. The rear part of the head steady to the cylinder head is just to hinder engine from rocking. I think that the design gives more lateral flex. Riding bumpy bends at high speed (100+) possible without wobbling. Way better than the Goldie I had after the Dommie.

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Take a look at a BMW Airhead frame, ie R90 or R100 etc. They are a blatant copy of a Featherbed Wideline frame, except they use a single top frame tube like a traditional frame, done supposedly specifically to allow more lateral flex when cornering. And it works. The old Airheads, with the suspension set up right, are dead stable on the cornering yet very supple and much more comfortable to ride long distance than bikes with firmer suspension. The R65 650 BMW is a few inches shorter in the wheelbase than its bigger brothers and a few inches lower, and feels just like my Norton Atlas to ride - minus the vibration and about 10 hp. I reckon it has about the same frame geometry. But for racing the Beemers, some guys added brace tubes from the swingarm pivot area to the bottom of the steering head. So they must flex a bit too much under race conditions. Shoulda just copied the whole Featherbed!

Old Beemers were/are called rubber cows. They don't handle nearly as well as the Featherbeds, despite their similarities. I've owned and ridden both as well. The aftermarket braces do help though.

The Beemers' tendency to buck when accelerating doesn't help, nor does the heavy transverse flywheel, nor do the junk forks. Never could get mine to feel neutral, and man, did I try. I'm sure some of it is in the inherent engine design differences, but that's part and parcel of the bike and can't really be separated.

They are excellent touring bikes, but they are quickly over their head in the twisties. I ride with a friend who picked up an R100 last year, and he is much slower on that bike than his others. He's an excellent rider (actually an instructor), but his comfort/speed is much reduced on the Airhead. I prefer riding with him on his modern bikes.

As far as Featherbeds are concerned, I like the Wideline. The width of the seat allows me to distribute my weight more on my thighs/butt and off my wrists for better comfort, lighter steering. All this is with clip-ons, so a different handlebar may change that weight distribution and my opinion, but it's good to at least talk myself into thinking that I like my bike best. Much cheaper that way!

Lots of frames copied the Norton steering head, which may have been the wrong bit to copy.

Bill Horsman used to race Jerry Kooistra's Mk3 Seeley G50. He told me he thought he could feel the front end 'walking' when he pushed it hard during races. I have never felt that, but I have a piece of gusseted chrome-moly tube bolted in front of the motor, instead of the usual ladder. I raced a featherbed bike for a lot of years and never felt the front end 'walk'. My Seeley stays more upright than most featherbeds, so the side loading is probably even greater than occurs with a featherbed. With the featherbed frame, I could never corner as quick as I can with the Seeley. It is a very different deal. The Seeley is definitely a step ahead of the Featherbed. I could never ride a Featherbed bike with such disregard for my safety. Even with a Manx, you always need to be 100% on top of it.
My mate's 650 Triton is a very nice bike to ride, but it has it's limitations in corners. My 500 Triton was faster in corners, but it's power characteristics put it at a disadvantage. 'Torque wins races'. I am glad I sold it. My Seeley 850 is a world apart. That big motor in a Featherbed frame, would not be very good. To my mind, a Norvin is a disaster. I would not like to ride one.

It is never as simple as 'the best motor in the best frame gives the best bike'. I think a lot of guys try to add up the effects of all the possible modifications without recognising the pattern involved. In the end, it is the 'package' which counts - how it all works together. On Winton Raceway, an RS125 Honda would beat any classic bike.

I have never felt unsafe pushing my Featherbed hard through corners, in fact I feel very safe cranking it over and powering it through coroner's, when I first built it I ran flat bars for a lot of long years of riding it, was a great position but my later years have gone the Euro bars for a bit more upright and comfort, still feels good pushing it hard in the corners, maybe Al you didn't feel safe because the Featherbeds you rode all so long ago wasn't set up right and under powered as you need to use the torque of the motor for the Featherbed to handle great in the corners, in fact sometimes I look back and think did I really go through that corner at the speed I did, I have always said my 850 Featherbed is like it's on rails when pushing hard in and through the corners.
When I first built my Featherbed it took me 2 months of riding it and getting the feel of the Featherbed before I started to find how sweet it was in the corners and how to use the power/torque of the hot 850 motor, even better now with better tyres that weren't around in the 80s, the old style K81s are just not there no more and it also depended where the K81s were made back in the day, the Avon RR made a big difference in how far I can push it compared to the old K81s.
Back in the days I did try other brand of tyres on the Featherbed and to be honest some tyres did feel unsafe in the handling, so Al maybe it was your tyre choice that made your Featherbed feel unsafe or the rider.

Ashley

ashman said:

I have never felt unsafe pushing my Featherbed hard through corners, in fact I feel very safe cranking it over and powering it through coroner's, when I first built it I ran flat bars for a lot of long years of riding it, was a great position but my later years have gone the Euro bars for a bit more upright and comfort, still feels good pushing it hard in the corners, maybe Al you didn't feel safe because the Featherbeds you rode all so long ago wasn't set up right and under powered as you need to use the torque of the motor for the Featherbed to handle great in the corners, in fact sometimes I look back and think did I really go through that corner at the speed I did, I have always said my 850 Featherbed is like it's on rails when pushing hard in and through the corners.
When I first built my Featherbed it took me 2 months of riding it and getting the feel of the Featherbed before I started to find how sweet it was in the corners and how to use the power/torque of the hot 850 motor, even better now with better tyres that weren't around in the 80s, the old style K81s are just not there no more and it also depended where the K81s were made back in the day, the Avon RR made a big difference in how far I can push it compared to the old K81s.
Back in the days I did try other brand of tyres on the Featherbed and to be honest some tyres did feel unsafe in the handling, so Al maybe it was your tyre choice that made your Featherbed feel unsafe or the rider.

Ashley

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My 500cc short stroke Triton was all top end and very little torque. My mate had built it and crashed it at Bathurst in about 1958. When I got it, it had 4 inch megaphones and the motor was an inch back in the frame. When I started racing it, it turned me into an instant dud. I fitted a two into one exhaust and moved the motor forward as much as possible. I then started getting decent lap times. But whenever i approached a corner I had to maintain my speed. If the revs dropped below 5000 RPM, I would have to slip the clutch to come out of the corner. When the motor came on song, the bike would usually go sideways. That is probably what caused my mate to hit the Armco fence at Bathurst in 1958 and broke an arm and a leg. If I ever got balked in a high speed corner, I was in big trouble.
A Manx is very different, but any Triton is never as good as a Manx. My mate's 650 Triton is fast and safe, but a good guy on a Manx would always beat it.
My Seeley 850 is totally different - it never does anything stupid.
When you ride bikes on public roads, you do not usually ride them near their limit. My problem is, I only know one speed, so if I ride on the road, I get frustrated. If you ride slow on a race circuit, you are more likely to crash. You sometimes see guys crash on their way back to the pits after a race has finished. They inadvertently pass their braking point and grab the brake. When I finish a race, I do not back-off much on my way off the circuit.
For me, even driving my car on public roads shits me. You get lulled into a false sense of security. When you race, you always concentrate fully. When I approach any corner on a race circuit, I know the speed at which I can get around it.

Ashley, if you have never raced, you might not realise that when you watch a road race that what you see is not what you get. That stuff about 'race on Sunday, sell on Monday' is bullshit. I would never buy a modern sports bike for use on public roads. A nice original Commando would be much better. A couple of times recently I have seen guys on modern bikes in 60 KPH traffic and sounding as though they are using heaps of revs.

Well I am a fully experienced rider done my share of track days racing mates flat out (young and silly but you learn a lot), try riding around Lakeside raceway it will show how good you are, but I like riding anytime it pleases me, riding once or twice a years (in your own admission Al 23 years not riding at all) is just not my thing, my motor is built for high revs running, I don't worry about how others ride, I always push my bikes hard as I have to the keep with my experience sports bikes riders mates who have been riding as long as myself, so far they haven't lost me and they don't get past me when I get the lead, riding hard up in the tight twisties up in the ranges you have to ride like a racer with my mates, a twin shock bike will never out handle a well set up sports bike, but you be surprised with an experience rider on board.
But Al you have never like riding on the road and maybe that's a good thing as I wouldn't like to be stuck behind you.
So Al you can talk all day about your race days long gone by, seems to be more memory for you now, I live to ride no matter what anytime I feel like it and the only time I ride around town or the city is when I am out visiting friends, or going out for a ride away from the suburbs or traveling, I live to ride so simple and nothing better than riding with trusted mates, no matter what bike I am riding.
50 years in the dirt as well on the road, I think I know what I am doing and you learn by your mistakes as no one is ever perfect, we all make mistakes.

Ashley

HopperXL said:

Take a look at a BMW Airhead frame, ie R90 or R100 etc. They are a blatant copy of a Featherbed Wideline frame, except they use a single top frame tube like a traditional frame, done supposedly specifically to allow more lateral flex when cornering. And it works. The old Airheads, with the suspension set up right, are dead stable on the cornering yet very supple and much more comfortable to ride long distance than bikes with firmer suspension. The R65 650 BMW is a few inches shorter in the wheelbase than its bigger brothers and a few inches lower, and feels just like my Norton Atlas to ride - minus the vibration and about 10 hp. I reckon it has about the same frame geometry. But for racing the Beemers, some guys added brace tubes from the swingarm pivot area to the bottom of the steering head. So they must flex a bit too much under race conditions. Shoulda just copied the whole Featherbed!

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Blatant copy of a Featherbed Wideline frame with single top frame tube, well that's not a Featherbed frame or a copy, a Featherbed frame don't flex and hard mount motors are part of the solidness and why they handle so well.

acotrel said:

I have got to do it again. It is better than sex.

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Better than sex, well I love riding whether sex or bikes, maybe your doing things wrong in the bedroom Al.

ashman said:

Blatant copy of a Featherbed Wideline frame with single top frame tube, well that's not a Featherbed frame or a copy, a Featherbed frame don't flex and hard mount motors are part of the solidness and why they handle so well.

Better than sex, well I love riding whether sex or bikes, maybe your doing things wrong in the bedroom Al.

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Separate beds and separate motorcycles are always better. You need two beds and two motorcycles. You cannot use your road bike for racing. And you cannot use your race bike for road use. You suggestion that I should put my Seeley 850 on the road is not really practical I would have to completely rebuild the bike from the ground up. If I rode it on the street, even first gear would be impossible. When it moves from a stand-still, it usually lunges forward then staggers-off a bit, then goes like buggery. It would jump straight into the back of a car - on a race track, you just put your head into neutral and let it happen.
I first built the Seeley in 1978. I did not race it until 2002. With a new bike, it always takes time to get it right. My Seeley was no different, but I had the advantage that I knew what it should be doing. There were several minor changes which made a very big difference - every one of them moved the bike further away from road use.
I cannot think of a similar situation which happens with hotted-up cars. There is no equivalent. I was talking to a race car driver at Winton a while back who said the bikes are dangerous. I never feel as safe on public roads in my car, as I do on a race track with my bike. On a race track, the risks are always manageable and tolerable. Car drivers do not look after each other. With them, it is every man for himserlf.

It's all good Al we all have different ideas, if you did build your Seeley for the road a standard gear box would be needed anyway, but the thread is all about Featherbed frames and nothing more, have a good happy new year Al and hope you do get on your Seeley soon one day.
It's aways good to agree to disagree on what we do on our motorcycles, myself just couldn't go so long without one between my legs, a week is to long for me.

Ashley