Simon Crafer Gyroscopic Effect and Inertia

acotrel said:

I cannot understand why some of you guys worry so much about crashing. You need to learn how to put a motorcycle on the ground without hurting yourself. The only problem with doing it, is if where it happens is not a smooth surface, so choose where you stick your neck out. And if you crash - keep your arms and legs in and don't try to save yourself.
Riding on public roads is ten times as dangerous as racing.

Click to expand...

Over the years I've been a bloody expert at getting knocked off and thrown down the road due to ice or snow, odd things like a blown front tyre etc. I made my mind up 30 years ago not to let it happen again and so far I've been lucky.
A few days ago a blind bas**rd driving a big white van tried to cross a roundabout between me and the car I was following round. Luckily I got the bike stood up while hitting the stoppers as hard as I dared and by throwing the bike left I missed him by inches. How the hell he didn't see me I will never know the LED head light as usual, the bike is pretty loud, I was only a couple of car lengths behind the car I was following and it was broad daylight.

I rode motorcycles on public roads until I was 29, then road raced. These days I drive cars on public roads. It is only on very rare occasions that I get apprehensive about road racing a motorcycle, and my wife does not understand that. I have done all the crashing I am ever going to do on race tracks, regardless of whether I race or not. But I cannot say the same about driving my car on public roads.
It would only take 5 laps of Winton today, to get me to become fast enough to race again. We all become programmed.

I had to laugh. Keith Campbell was an Australian rider who raced in Europe in the 1950s - he married Geoff Duke's sister, then died at Oulton Park. His brother George has a son who is also called Keith, who races motorcycles. Young Keith has won a few races. He was a bit surprised when George got on Keith's bike and lapped faster than Keith.
In the old days we all rode shit bikes.

Ashley, about overthinking - I am sorry I mentioned my professional qualifications. You work in the best place to become educated. My whole life has been based on 'recognition of prior learning'. I think I have failed more subjects than I have ever passed. At High School, I failed most of my Matriculation exams. In that year, out of 300 boys, 92 became medical doctors. I had to laugh when I saw this video - the guy has got it right :

acotrel said:

I cannot understand why some of you guys worry so much about crashing. You need to learn how to put a motorcycle on the ground without hurting yourself. The only problem with doing it, is if where it happens is not a smooth surface, so choose where you stick your neck out. And if you crash - keep your arms and legs in and don't try to save yourself.
Riding on public roads is ten times as dangerous as racing

Click to expand...

In 50+ years of riding dirt and road bikes I have never worried about crashing at all when on the bikes, never think about it, learn how to crash, so Al you are saying we all should just crash our bike to find out how to crash safely, who cares about the damage doing so to the bike or ourselves for that matter, get a dirt bike and you will learn very quickly in how to come off safely from losing it in fast power slides or taking a crash from jumps to sliding into other dirt bikes, most of the time it's the other riders fault, too miss judging tree positions etc. etc.
Accidents can happen anytime and most times you don't have time to think about it as it happens so quick before you know it your on your arse or flying over the handle bars at high speed.
I been down many times mostly in the dirt and a few slide outs on the road from my own mistakes but have had 3 accidents from a car running over the top of me while I was stopped to turn into a mates drive way (had no idea till I got hit from behind) had to stop to give way to on coming traffic and 2 time putting the bike down when a car stopped in front of me, first one the car brake lights weren't working and the second and last time about 12 years ago a young woman had her left indictor on but turned right while I was just about to go around her on her right side.
As I say we don't plan on accidents but they happen and they happen so quick that thinking how will I handle this crash, you be on the ground before you get the chance to even think about it, but one thing I do know you get hurt more if you stiffen up, but one thing is I have been injury lucky in the times I have been down hard, 2 left knee injuries, and once when the Norton spat me over the handle bars avoiding being hit by a car, fracture left elbow and broken left thumb but most crashes just involve lots of pain from gravel rash, not from the accident but getting the gravel scrabbed out of the wounds.
Learn to crash your bike, no thanks I just let 50+ years of experience dirt and road biking time will get me through any crash time, but my main plan is to stay upright and not worry about crashing at all, no thanks I just keep riding and enjoy my bike time to not even think about crashing.
The best thing for me every time I have been down no major damage to the bikes maybe a few bent foot pegs or in the case of the Norton foot peg just broken away, try riding home with one broken foot peg, not easy but have done it.

Ashley

ashman said:

In 50+ years of riding dirt and road bikes I have never worried about crashing at all when on the bikes, never think about it, learn how to crash, so Al you are saying we all should just crash our bike to find out how to crash safely, who cares about the damage doing so to the bike or ourselves for that matter, get a dirt bike and you will learn very quickly in how to come off safely from losing it in fast power slides or taking a crash from jumps to sliding into other dirt bikes, most of the time it's the other riders fault, too miss judging tree positions etc. etc.
...................

Click to expand...

When I bought my first two wheeled vehicle with an engine in it, I had no idea my father had ever ridden a motorcycle. That wasn't the only thing I didn't know about him.

Anyway, he asked me if I had fallen off it yet? No?, well you should, and learn how to do it.

It was later that I discovered that as a Royal Marine in the mid 1940s he had done dispatch rider training, followed by truck driving training, rather than send him to Normandy or Burma, they selected him to be trained as an instructor.

He made it very clear however that falling well was part of riding well. Wish he had been able to pass more knowledge on, I have never been very good at falling off!

Ashley, motorcycle road racing is only really dangerous until you have your first crash, because until then you do not know what you are doing. Dirt bikes cause more injuries than road race bikes. I used to tune two Bultaco scramblers for a mate - a 360 and a 250. The 360 was great - it made other bikes go backwards, but I could only really ride it uphill - downhill scared me shitless. I don't like sailing in mid-air past big gum trees.
I have also ridden a speedway sidecar - I don't like that much either.
I think in road racing my total number of get-offs has been about 7 - all at high speed. I have only copped one injury, and that is the one which worries me - my helmet had a flat worn on the top of it, and the injury was a dislocated collar bone. I did not get my hands off the bars quick enough, so got launched - no steering damper.
Ashley - I think, if you went road racing, the memory of what you are now doing on public roads would really freak you out.

SteveA said:

When I bought my first two wheeled vehicle with an engine in it, I had no idea my father had ever ridden a motorcycle. That wasn't the only thing I didn't know about him.

Anyway, he asked me if I had fallen off it yet? No?, well you should, and learn how to do it.

It was later that I discovered that as a Royal Marine in the mid 1940s he had done dispatch rider training, followed by truck driving training, rather than send him to Normandy or Burma, they selected him to be trained as an instructor.

He made it very clear however that falling well was part of riding well. Wish he had been able to pass more knowledge on, I have never been very good at falling off!

Click to expand...

Geoff Duke was trained as a dispatch rider - it did not do him any harm.

Al dirt bikes of today are so much quicker, more powerful, lighter, better suspensions than dirt bikes I started on (50 years ago and I still ride in the dirt), same as modern race bikes and road going bikes, an old classic racer will have nothing on a late model race bike.
You talk up your Seerley in how good it is but I recon I would run circles around you on my 1200 Thruxton on the track, and yes I have done track days, come for a ride up in the tight twisties with me and the mates and we will open your eyes, but then you no longer ride.
I have never been injured on my dirt bikes in 50 years of riding them and I been down more times on dirt bikes than any other bike, come jump on my Honda CRF450X, it will blow you off the mark on your Seerley, but you no longer ride so we are all safe.
I have also walked away from road crashes but my last one 8 years ago when thrown over the front of my Norton my left elbow hit the tar with force and got my first fracture/broken bone from riding bikes, so 50+ years of riding bikes I think I have done well, my bikes are my life and I ride all the time, they don't scare me.
I am not going to say no more as really we heard it all before.

Ashley

ashman said:

Al dirt bikes of today are so much quicker, more powerful, lighter, better suspensions than dirt bikes I started on (50 years ago and I still ride in the dirt), same as modern race bikes and road going bikes, an old classic racer will have nothing on a late model race bike.
You talk up your Seerley in how good it is but I recon I would run circles around you on my 1200 Thruxton on the track, and yes I have done track days, come for a ride up in the tight twisties with me and the mates and we will open your eyes, but then you no longer ride.
I have never been injured on my dirt bikes in 50 years of riding them and I been down more times on dirt bikes than any other bike, come jump on my Honda CRF450X, it will blow you off the mark on your Seerley, but you no longer ride so we are all safe.
I have also walked away from road crashes but my last one 8 years ago when thrown over the front of my Norton my left elbow hit the tar with force and got my first fracture/broken bone from riding bikes, so 50+ years of riding bikes I think I have done well, my bikes are my life and I ride all the time, they don't scare me.
I am not going to say no more as really we heard it all before.

Ashley

Click to expand...

I have ridden with superbikes on track days and I know what fast is around Winton. They are faster down the straights. Around the tight stuff, they cannot get the power on the ground. An RS125 Honda can beat them. I have watched it happen. People who ride on track days often seem to ride without focus. When I ride, I always ride with the same mindset. When I first came to Benalla, I had an RD250LC. It was simply silly stuff. I used to feel sick while riding it on public roads.
I have never raced a modern motorcycle - I would not do that. I know myself too well. It would just be idiocy. There is a friend of a friend who is a millionaire. He was a champion in Formula 5000 car racing. Because of a divorce he decided he could race bikes. If I had given him a big mouthful of abuse, I could have saved him from a lot of pain. His first race was on Phillip Island with a modern 600. As he went over Lukey Heights, he grabbed a handful of throttle and lost the front. He bashed his head on the road and broke his sternum. In hospital, the nurse interrupted his oxygen supply and cause a bit of brain damage, then the golden staph got into him. He is OK now. But it really irks me. Before he did it, I heard what he was saying, but I could not set him straight. He had completely the wrong mindset. Always start slow and work up to speed - never speculate or work on supposition. Motorcycles are not cars. I have known 3 racing car drivers who have done the same thing - crashed almost immediately through lack of restraint. Even today, it would take me 5 laps of Winton before I could race, and I know the circuit extremely well. I would not race at Phillip Island, any crash there is a really big one.

acotrel said:

, it would take me 5 laps of Winton before I could race, and I know the circuit extremely well. I would not race at Phillip Island, any crash there is a really big one.

Click to expand...

You keep telling us this all the time but how would you know now, at 84+ years old and you haven't been on your bike for over 10+ years, maybe even longer, as you get older the body slows down, you seem to be very smart on the things you have done in your life but, maybe it's a good idea you are no longer riding, your brain might be working but your body might not be working with it.
Maybe it's time to give up on your bike and hand it to someone who could make it better, put a decent gear box in it might make a great road going bike, take notice like our old mate Ywas (think thats close enough how it's spelled) with his road going Seerley he mod for his old injuries.
Old age is a bitch and we all will go through it and Al you seem to be a decent person but you got to know when it's time.
Racing is not everyone's things same as road riding is not your thing, myself and others ride on the road because we love the freedom and can ride anytime we like, it gets rid of frustrations and anything in life that is thrown at us.

Ashley

Seems appropriate…

I know what I did they last time I raced, and so do they. There used to be 14 of those Hondas racing that class.
They probably cost $30,000 each, My bike was built for less than $3000 and I was more than twice the age of those kids. I do not need to go there again. That is the only time I have ever had a bike stop during a race, and of course it had to happen when I had them cold. If I ever go there again, it will be with 6 speeds close ratio - NOT 4. I would be in the first corner with them. My problem has been believing bullshit about handling. I did not know why Manx Nortons were so good until I rode one.
They OVERSTEER when gassed on a lean - so they are much faster in corners. Try increasing the trail. I found out simply by chance - not by design.
It was not obvious from feel, that the bike could be accelerated all the way through corners.

I am faced with the fact - if I break my hip, I will die in a nursing home. My wife has said I may race again, but if I crash I have to die - not come home injured. I cannot race with that sort of negativity in the background.

acotrel said:

I am faced with the fact - if I break my hip, I will die in a nursing home. My wife has said I may race again, but if I crash I have to die - not come home injured. I cannot race with that sort of negativity in the background.

Click to expand...

If that’s for real then good for you, at least you’ve made a positive decision and can now move on.

Find some young hot shot to put on it whilst you still have the wherewithal to get involved and help the kid to learn.

It’ll give you a new lease of life !!

I always thought the perfect corner would be the one where the transition point between braking and accelerating in a corner would be in the middle with no 'no gas' situation. With enough trail, the transition point can almost be before the corner. The last time I raced, the transition point was just inside the corner, then I was full blast all the way around and up the next straight. You will never high-side a commando-based motorcycle, unless you break a chain. A Moto GP bike or a two-stroke is an entirely different story.

Fast Eddie said:

If that’s for real then good for you, at least you’ve made a positive decision and can now move on.

Find some young hot shot to put on it whilst you still have the wherewithal to get involved and help the kid to learn.

It’ll give you a new lease of life !!

Click to expand...

My brother races speedway sidecar. A while back he let somebody else ride it with my brother's passenger. The crash meant my brother's passenger cannot race again. When you put kids on a race bike, you take responsibility for them. Many years ago I was involved in a court case which involved an industrial fatality. I never want to be questioned like that again. I am happy my kids never wanted to race after they watched me slide down the track at about 90 MPH on my back.
It is OK for me to be stupid on my bike, but nobody else.
I will be visiting Winton Raceway again, a lady friend is still in the car club. I will check to see if there is an opportunity to have a ride. I would still like to make an on-board video to show what the bike does. It is a bit different.

I have put this stuff about trail here for a reason. It is important and I believe a lot of people have got it wrong. However I suggest when Peter Wiliams specified the steering geometry for the first Commando, his mistake was the lack of steering damper. Most people have never experienced a full-on lock to lock tank slapper, and do not know how to survive one.
That Featherbed Atlas which Ashley has should handle like a Manx Norton, but it would need rear springs soft enough for the rear to squat about an inch when he accelerates in corners, when on a lean. If his motor is as far forward in the frame as possible, the bike's handling should be excellent, as long as it has 19 inch wheels.

In one of the videos on cornering, they say - if you get into a corner too hot, you need more lean. I suggest the opposite is true. I usually get right out and over the inside of the bike, while I am washing off speed, and when I judge I and slow enough to have grip, I accelerate, and the bike steers itself. It is safer to accelerate when you have less lean. More trail gives less lean. It is impossible to accelerate safely when your bike is at an extreme angle of lean.

acotrel said:

That Featherbed Atlas which Ashley has should handle like a Manx Norton, but it would need rear springs soft enough for the rear to squat about an inch when he accelerates in corners, when on a lean. If his motor is as far forward in the frame as possible, the bike's handling should be excellent, as long as it has 19 inch wheels.

Click to expand...

My Featherbed is not a Atlas Al it's a 1957 Wideline frame with an 850 Commando motor, Atlas were Slimline frames and 750 motors, they also made Slimlines with 650/650SS/ES2, I also am building a project bike a 1960 Manxman that was an ex race bike so not the original 650 motor, I was lucky and got it in boxes cheap but the head was missing, had twin carbs set up, high dome top pistons and the crank has been balanced and open megaphone mufflers.
I run Commando Koni shocks on the back, spring are on the soft settings and the damper are number 3, use to set them on 4 but when I rebuild them I put 5wt heavier oil in them so had to run them on number 3 setting, when I accelerate in the corners the rear grips the road pretty good, I run 19" Akront alloy wheel front and rear, the Slimline has 18" alloy rims and I brought a new set of Ikon shocks for the rear they are shorter than the Wideline shocks but have the same setting as my Koni shocks.
I was lucky when I first built it back in the early 80s I got it right the first time by doing the things differently to my mate Don's set up who got me into Nortons and Featherbed frames, learned by his mistakes, my motor is built very much like a Combat motor but with improvements and balanced for the Featherbed frame (it's very reliable and street safe), my set up works so well no matter how I ride it, it just grips the road whether running high speeds, powering through corners, or just putting around, it's such a fun bike to ride, no matter what I throw at it and being a light weight bike and good gripping tyres, I wouldn't change a thing, but the last 15 years when I had spare cash I did a lot of new bits upgrades to make it a better bike, but the motor is still the same and the Joe Hunt was one of the best investments I did to it.
As for tail, rake, oversteer, understeer, those things just does my head in thinking about it all, all I know is my Norton is well set up for me and my riding style and for cranking it in the tight twisties up in the ranges, it has great acceleration (is very quick from slow to opening the throttle right up), everything is built up high or tucked right in and nothing can scrape when cranked over hard.
It's my hotrod bike and I love riding it, so much fun.

Ashley

Your bike sounds as though it is a very good thing. Are you aware of which way it goes when you brake into a corner in the middle of the road on a lean, then immediately gas it hard enough to make it squat. I only found out by guesswork and trial, that my bike oversteers in the correct direction. I had noticed I was able to stop braking and get on the gas earlier. It is a real advantage when competing. My problem then was in finding the reason it can do that. Unexplained things can sometimes bite.
I don't know where I got the idea, your bike had an Atlas motor, I know very well it is an 850. I once saw a similar bike in a pre-1962 historic race. I think that is a good thing to do. It could be like a supercharged Manx.
In my early racing days, I was a total idiot - I did not know where to find information. These days, most things are on the web. It is much better, but too late.