Back wheel balance with an electric wheelchair?

[Scooterman]

I used to be able to do it with a manual wheelchair, and it came in handy at times. But I don't believe it's even feasible with an electric wheelchair, or is it?

[Burgerman]

Absolutely it is.
I used to do it all the time. Its actually very easy if you have a feel for it.
Rearward CG, no anti tips in the way, a chair that is PROGRAMED to respond instantly, and normal hand control. You fall out rearwards a few times learning. Do it on the grass. But I wasnt 65 then...

I used to do this stuff down motoways at speeds you wouldnt believe. And the the drag strip for fun through every gear. Obviously on very powerful bikes. So now I am not so inclined to try it even in a chair. And prefer anti tips...

This is safer... About as far as I want to go now.
http://www.wheelchairdriver.com/doomed/wheeliesnow.mp4

[Scooterman]

You make it look easy BM! I didn't think it was possible. I don't like going up the ramp on the bus if it's steep. Because of parked cars sometimes the driver can't drop the ramp onto the kerb and drops it in the road instead which makes it's really steep especially if the bus doesn't lower far enough. If so I reverse up but I notice the rear wheels don't grip as wheel when going up a ramp backwards. I suppose it has something to do with weight distribution?

Re bike wheelies, I don't know how riders have the nerve to pull a wheelie on bike at high speed, and keep it balanced.

[Burgerman]

Bikes...
What happens is that as you accelerate on a superbike is that the front wheel just climbs. You cant really stop it if you give it any. I spent years drag racing turbocharged and nitrous injected 1100cc bikes... These were also road bikes. The things have the power to flip even in top gear at speeds that you really really wouldnt believe.

After a few thousand small accidental wheelies, you learn to ignore it and shut the throttle a little or push the rear brake with your foot to stop it getting too high. After a few years you realise that it doesent matter that the front is airborn, you can still change gear etc. And with some practice you can steer and overtake cars, go up the gears for a mile at a time on 1 wheel. Become 2nd nature you dont need to think about it. Balance? On the throttle.

[Burgerman]

Watch this bloke...
I used to do this stuff all the time. Big bikes are so fast, accelerate so hard, rev so high that most people will never know how extreme they are. Including 80% of their owners. You have to be very committed to use all that power!

The difference here is that he has half the horsepower, no turbo, no nitrous... Just a stock litre suprbike.

I did seriously used to ride like that (in germany officer) and it didnt really feel that mad at the time. Its just what I did day to day much of my adult life. Working for bike magazines, drag racing modified street bikes, testing at 2 mile runways (bruntingthorpe) and race tracks every week, etc. It all sort of fitted together. Wheelies just came with the territory. I wasnt alone, many of my freinds and work colegues and fellow street bike racers all behaved a little mad in those days.

Looking back at this stuff now all looks a bit insane. But it didnt FEEL that way at the time. So wheelies in a chair dont exactly stress me much!


youtu.be/YnVDzuRc5r0

[Scooterman]

[quote="Burgerman"]

Looking back at this stuff now all looks a bit insane. But it didnt FEEL that way at the time. So wheelies in a chair dont exactly stress me much! [quote]


Good grief Burgerman that video's got to be the most insane thing I've ever seen! There's a famous bike video of a guy in sweden called ghostrider or something, doing 10 minute run form Uppsala to some other swedish town. But it's nothing compared to that R1 rider, especially that super high speed wheelie and when he darts in between two adjacent vehicles. But on a serious note, I wonder whether a rider high on the adrenaline could take on one risky maneuvour too many, especially with the consequences so high. If his mother saw that video she'd have a coronary!

The complete opposite of superbikes. I watched the isle of wight annual scooter ride out this afternoon. There's thousands of scooters from all over the country, but they make a horrible din, a raspy tinny pop pop sound. But good fun to see.

[Burgerman]

Scooters not my thing...

That guy on the bike isnt doing anything that I didnt do on occasion. I didnt do that all the time. Just when I thought no stripy cars around.
Many of my freinds that were into bikes/drag racing etc were all a litte crazed by power too. You dont normally get to see it thoughBut today video cameras are cheap and good quality.

It looks worse because he's diving in and out of the cages.

I used to drive around the traffic too when it was busy like that. Its easy enough. Just not strictly legal... Yes you do get a bit adrenalised. All that performance corrupts your brain. But wheelies are easy as the bike does the work. You literally cant help it. Just a matter of throttle! And the bike steers and controls exactly as before. Wanna go left? Lean left. Wanna lower the front? less throttle. Want to lift it, more throttle. Need a new gear? Just do it like its on the ground. The bike doesent care. Its really not hard doing high speed wheelies when the bike just wants to do it. You simply accelerate hard and thats it! Its actually frustrating that its got more go in it, that you cant use.
Remember that 1st gear is 70 plus. 2nd is 110/120 mph. IN 5 SECONDS from parked. 10 seconds from 0 to 150mph. 192 max speed. 200mph plus if you de "regulate" its emmissions nonsense.

[Scooterman]

Scooters not my thing...

It looks worse because he's diving in and out of the cages.

No I didn't think scooters would be your thing. They're more of a fashion statement; culture, music, clothing vibe. They're not really my thing either but I like the fact that they celebrate british culture something that's frowned upon today.

"Cages" I've never heard that term before, it's quite appropriate. And obviously only a term used amongst the superbike community.

[Scooterman]

Here's another video of that R1. There is a lot of debates in the comments whether the speedo is in kph or mph, most seem to think kph. But eventually the R1 rider chips and says mph.

youtu.be/xrH8VEs46Zs

[Burgerman]

Cages? Yes. Cars obviously! Thats how they look to bikes...

Mostly they are like mobile chicanes. In the way. What worried me wasnt me hitting one, they move slowly. But if you watch in the mirrors as you pass them at at about 3x their speed they swerve and it seems to shock them. Something goes whoosh and they didnt know it was coming. Makes them jump.

I tended to only treat cars that way like the vid when abroad. In this country I am likely to end up in trouble! So daft speeds on quieter stretches of roads or motorways. I like a non dangerous level of congestion at silly speeds. Today, you would get banned in a week. Cameras everywhere! Back then I had a number plate that said performance bikes, GSXR1100, DynoPower, Burgerman, etc instead... Having already had a lot of driving lisence issues.

[ex-Gooserider]

I've heard the "Cage" reference for cars from every class of rider, from the super-bike crowd to the chopper / "biker" crowd, as well as the touring bike folks...

A lot of years back, there was a guy Doug Domokos or something like that, who was billed as the "Wheely King" who claimed to be able to wheely any bike, any time, at any speed and hold it for as long as he wanted, including at a dead stop... He was hired by Kawasaki, and did all sorts of shows on different bikes. At the time, the largest bike on the market was the KZ1300, a 6 cylinder, liquid cooled heavyweight aimed at the touring market... Domokos said that he got a lot of grief from KZ when he was using one in his shows because they were tired of having to keep replacing the tail lights on his bikes...

ex-Gooserider

[Scooterman]

Yes very easy to lose license in UK. I think getting caught doing 100mph+ on the motorway results in an instant ban unless you're a celebrity or premier footlball and can employ a good barrister who can argue your case on so-called 'hardship' grounds.

They used to say spraying the number plate with hairspray defeated the speed cameras. Sounds like a shaggy dog story to me.

Back then I had a number plate that said performance bikes, GSXR1100, DynoPower, Burgerman, etc instead... Having already had a lot of driving lisence issues.

I remember seeing your Burgerman plate on a bike magazine cover you posted. But I didn't realise you used that plate on the road!

[Burgerman]

Only by "mistake"...

[jamieelara]

Really fascinating to read through this thread. It’s wild how much crossover there seems to be between bike culture and the way some of you describe handling electric wheelchairs. Makes sense though — balance, weight distribution, throttle (or joystick!) control — it’s all about feel.

Scooterman, I totally get what you mean about reversing up steep bus ramps. I’ve run into the same issue and always felt it was down to weight shift and traction. Sometimes it feels like the rear wheels just don’t “bite” the same way in reverse.

And Burgerman, those old superbike stories are something else! The way you describe throttle-controlled balance makes it sound second nature after a while, but for most of us, even small ramps are enough to make the heart race.

[Burgerman]

When you spent half your week at work (emap publications, perf bikes, mcn etc group testing bikes and dyno testing etc at bruntingthorpe, the weekends drag racincg them with 4 or 500 horsepower it IS 2nd nature. You really dont think about it. The only difference between front wheel off the deck by an inch or a foot is the throttle, regardless of which of the first 4 years you are in. Its the thing that stops you opening the throttle more or flipping it. So it really does just become a part of controlling the bike as you accelerate. If the front comes up an inch, thats fast. 6 inches, thats too slow as you have to keep closing the throttle or up it comes. But when you close the throttle you lose boost and the nitrous and it goes rich, bogs down so you try not to... You soon learn how to hover it 1 to 2 inches max to get the fastest times.

As for less traction in reverse in a chair that is also true. On Rear Drive. Think about where the CG position is. Imagine a point where your belly button is. Draw a line down. On level ground on a correctly configured chair, this should be around 2/3rds to 3/4 towards the rear drive wheels. So they have most of the weight.

As you face down a slope the centre of gravity or more accurately centre of mass (draw a line down vertically) is now more over the front casters. And theres little mass on the rear drive wheels. As you accelerate in reverse up that slope the CG pushes the front casters down, and lifts the rear drive wheels. Making it ever worse. The exact opposite to a wheelie. The weight tranfresr in the wrong direction.

The real problem in a chair is that almost every rear drive one has seperate swing away foot riggings. These MUST give clearance between your heels and a fully 360 degrees caster fork. So your feet are ahead of the caser wheels. If you have a hacksaw, a hammer, and some mind over metal, you fit a centre mount footrest. This allows you to move the seat back as your heels now fit in between the caster wheels at least to a degree. Now the chairs isnt rediculously nose heavy, steers better, is shorter, and you do not lose traction so easily in reverse. It o longer feels like an oil tanker.

My rear biased chairs are all this way. Heres the Dietz one... With seat moved back, and that tilt angle is fully lowered too so that it is rigid and not weak as I drive and not "wobbly"... Almost all the weight is on the drive wheels. Its tips back going UP a ramp! The high anti tip wheels dont save it!
So you hit ramps or anything likely to make it tip, flat out and decelerate up them to keep the front down. Just "feel" whats right...

Reflection in window...

[LROBBINS]

If you have seat tilt you can also move the CG rearward for going backwards up a ramp by tilting the seat.

[Burgerman]

That true for a single case reversing up a ramp. At least a little. But the chair still feels about a mile long indoors and steers terribly. You lose rear wheel traction even on the flat in shopping centres or smooth surfaces as the rear has less mass on it and needs much more "effort" in order to steer the front way out ahead with all the weight on it.

The real answer is mave seat back. But that will result in a much more tippy, shorter easy steering chair. Which is the whole point of course!

[ex-Gooserider]

My junky Jazzy is more or less FWD, and I find it will have trouble going up the ramp to our house when there is a lot of global warming accumulated on it, but it does just fine going up in reverse....

ex-Gooserider