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Formula 1 for your feet


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#1 jameson11

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Posted 14 October 2013 - 02:23

Wacky new skateboard with carbon fiber wishbone suspension!

 

https://www.facebook.com/BajaBoard

 

 


Edited by jameson11, 14 October 2013 - 02:31.


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#2 gruntguru

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Posted 14 October 2013 - 02:45

Yet another way to die.



#3 desmo

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Posted 14 October 2013 - 02:50

Crying out for a small block Chevy innit?



#4 gruntguru

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Posted 14 October 2013 - 03:50

With carb.



#5 Catalina Park

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Posted 14 October 2013 - 05:54

and cross plys



#6 Magoo

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Posted 14 October 2013 - 15:00



With carb.

 
You asked for it. Small-block Chevy V8, check. Holley carb, check. Curiously conceived reverse-direction hydraulic steering, check. 
 
avwt.jpg


#7 indigoid

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Posted 14 October 2013 - 16:02

 

You asked for it. Small-block Chevy V8, check. Holley carb, check. Curiously conceived reverse-direction hydraulic steering, check. 

 

Awesome, it even has an accessory mounted behind the driver

 

edit: it's actually even dumber than I first thought. That kind of seating makes sense on bikes where the seat leans over with you in the turns, but in a car... Not just dumb, but hideously unsafe. Is it some kind of new upper body / core workout fad perhaps?


Edited by indigoid, 14 October 2013 - 16:08.


#8 Canuck

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Posted 14 October 2013 - 20:57

It makes perfect sense for what it is. If they were side by side, it would look completely foolish (as opposed to generally foolish). It's clearly not built as an exercise in practicality thus it is entirely reasonable that function follows form. As if the reverse steering didn't state that outright already.

#9 jameson11

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Posted 05 May 2014 - 04:45

Hey guys,

 

The newest form of motorsport is on kickstarter!

https://www.kickstar... ... e-makeover

 

https://www.facebook.com/BajaBoard

 

10155902_628064663950692_167629555573849


Edited by jameson11, 05 May 2014 - 05:40.


#10 Kelpiecross

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Posted 05 May 2014 - 06:40

You asked for it. Small-block Chevy V8, check. Holley carb, check. Curiously conceived reverse-direction hydraulic steering, check. 
 
avwt.jpg


Since this thread has been resurrected - what does "curiously conceived reverse-steering etc." refer to? I can't see any reference to just what this means - presumably you turn the handlebars in one direction and the wheels turn the opposite way?

Apart from this I quite like this machine - nicely styled, "sits" well on the road, probably would handle quite well. As for safety - it would be many times safer than the fairly-numerous V-8 trikes you see on the road.

If it actually does have "reverse steering" - maybe the driver/rider is a pilot - rudder pedals in a 'plane are also "reverse" and in some early 'planes the rudder controls are actually like this.

#11 Greg Locock

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Posted 05 May 2014 - 07:14

http://www.mybikefor...ead.php?t=18511

 

yup, tiller steering.Should thin the herd.



#12 Kelpiecross

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Posted 05 May 2014 - 13:32

http://www.mybikefor...ead.php?t=18511
 
yup, tiller steering.Should thin the herd.


Thanks for that. I suppose with hydraulic steering you could swap the pipes on the rack over easily enough to make it steer as "normal". Maybe the builder connected the pipes up incorrectly by accident initially then kept it that way as a novelty or talking point - or maybe he really does want to die.

Edited by Kelpiecross, 05 May 2014 - 13:34.


#13 jcbc3

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Posted 05 May 2014 - 13:36

11502083591918450097.jpg

 

Dodge Tomahawk



#14 gruntguru

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Posted 05 May 2014 - 23:53

A friend of mine was scrutineering at Lakeside raceway many years ago. Some guys showed up with a just-completed "special". Apparently it was reasonably well built - a few minor defects only. The scrutineers were just about to sign off on it when they realised the steering was reversed. These guys were fully prepared to go racing at 100+ mph like that.



#15 Canuck

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Posted 06 May 2014 - 03:25

I suspect the electric board would be infinitely more fun.

#16 MatsNorway

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Posted 06 May 2014 - 11:06



#17 Lee Nicolle

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Posted 07 May 2014 - 12:20

Awesome, it even has an accessory mounted behind the driver

 

edit: it's actually even dumber than I first thought. That kind of seating makes sense on bikes where the seat leans over with you in the turns, but in a car... Not just dumb, but hideously unsafe. Is it some kind of new upper body / core workout fad perhaps?

Not bad but personally a Big Block would be better. 8 big trumpets through the bonnet.

As for the steering,,, WTF. It should be easy enough to use a quickener from the bars to the rack to make it half a turn lock to lock, and turn the bars right to make the quad turn right. Or just use whatever bigger quads use.



#18 Canuck

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Posted 07 May 2014 - 17:48

You guys are thinking car steering - think motorcycle steering instead. Push left, go left. Only makes sense if you've never driven anything but a motorcycle perhaps...pretty weak argument all around really. Don't get it.

#19 gruntguru

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Posted 07 May 2014 - 23:02

Not sure of the advantages of "Push Left go Left".

 

What's wrong with "Pull Left go Left"?



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#20 Greg Locock

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Posted 07 May 2014 - 23:15

Hang on, counter steering on bikes is not the usual cornering method is it? I shall have to ask Mr Foales for a trace of steer angle for typical maneuvers.



#21 saudoso

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Posted 07 May 2014 - 23:50

Only counter steering I'm sure is standard is aircraft rudder.



#22 gruntguru

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Posted 07 May 2014 - 23:57

Hang on, counter steering on bikes is not the usual cornering method is it? I shall have to ask Mr Foales for a trace of steer angle for typical maneuvers.

To turn left apply push left to roll bike to the left, then push right to start cornering and balance the overturning moment generated by the "lean".

 

So I guess it is "Push Left to go Left" - initially at least.



#23 Greg Locock

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Posted 08 May 2014 - 00:04

Ah, but is that the usual method? I would have thought that most people lean to start the turn and then steer into it. I could be wrong



#24 gruntguru

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Posted 08 May 2014 - 00:11

The only way to initiate a "lean" is to steer the opposite way.



#25 Canuck

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Posted 08 May 2014 - 00:35

I don't think I know how to ride motorcycles without push left go left. When I imagine trying to pull-left go-left to get into a turn, it's all very awkward, like it's pushing the contact patch and turning moment ahead of its straight-line position. Countersteering rolls the patch slightly backwards in combination with the weight shift and is a very natural feeling. Granted that's 20 years or more of riding motorcycles. It also provides, on a two-wheeled vehicle, very precise tuning of your lean angle without having to shift your weight.

I tried it on my bicycle. Once. Enough said.

#26 Greg Locock

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Posted 08 May 2014 - 05:43

I'm hearing a  loading of f-ing nonsense here. Let go of the handlebars, inititate a turn. You do it by leaning into the the turn. the handlebars follow, not lead.



#27 gruntguru

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Posted 08 May 2014 - 05:53

Agreed - there is a way to initiate a lean without turning the handlebars. It requires a rotation of the rider's body about the x axis which moves the COG off the centreline and initiates a lean. A bit slow - you can't turn sharply with hands off the handlebars.

 

You must steer away from the corner to roll in then steer into the corner.



#28 Kelpiecross

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Posted 08 May 2014 - 10:58


Certainly when I learnt to ride a bike (quite some time ago now) I was never told to steer away from the turn to initiate the lean - nor have I ever heard this before. If this does happen (and it may) it must be on an automatic/autonomic level - I have never noticed such a thing. I would have thought that telling a learner to steer one way and lean the other would be a certain recipe for going arse-over-head instantly.

It is a similar situation when teaching someone the very first basics of driving a car - when asked just how do you turn the steering wheel/change gear etc. - I find that I have to do it a few times and then watch what I am doing before I can put it into words - it is all done unconsciously.

Maybe somebody should jump on their bike now and just note how they initiate a turn - by leaning or turning away etc. (I don't own a bike at present).

#29 saudoso

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Posted 08 May 2014 - 12:29

Ohh I see now, I do it with the bycicle: you take it from underneath you by steering to the outside first, then commmiting to the turn, but that's nothing to do with push left to turn left, it's only turn right BEFORE turning left.

 

Ohh, and used to do that as a trouble kid when I'd want the rear end of my car to snap into oversteer.


Edited by saudoso, 08 May 2014 - 12:30.


#30 Magoo

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Posted 08 May 2014 - 12:34

Since this thread has been resurrected - what does "curiously conceived reverse-steering etc." refer to? I can't see any reference to just what this means - presumably you turn the handlebars in one direction and the wheels turn the opposite way?

Apart from this I quite like this machine - nicely styled, "sits" well on the road, probably would handle quite well. As for safety - it would be many times safer than the fairly-numerous V-8 trikes you see on the road.

If it actually does have "reverse steering" - maybe the driver/rider is a pilot - rudder pedals in a 'plane are also "reverse" and in some early 'planes the rudder controls are actually like this.

 

 

The steering on the vehicle is purely hydraulic,with no mechanical connection between the handlebar and the wheels. So just to see what it was like, mainly, the builder simply reversed the left and right hydraulic hoses so the steering worked in reverse.

 

He  says he was inspired by reading about and observing countersteering on motorcycles...in my view, without understanding fully what motorcycle steering is all about. 



#31 MatsNorway

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Posted 08 May 2014 - 14:56

From a pragmatic view it makes sence. Your putting lot of mass down on that side leaning over(should do at least) so naturally the steering gotta get out of the way for you. It also makes it easier to hold back against the forces wanting to trow you over.



#32 gruntguru

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Posted 08 May 2014 - 22:54

Certainly when I learnt to ride a bike (quite some time ago now) I was never told to steer away from the turn to initiate the lean - nor have I ever heard this before. If this does happen (and it may) it must be on an automatic/autonomic level - I have never noticed such a thing. I would have thought that telling a learner to steer one way and lean the other would be a certain recipe for going arse-over-head instantly.
 

Definitely not the sort of thing you can teach in a classroom then have all the students go outside and successfully ride a bike for the first time. The counter-intuitive steering is actually an action that we learn to control the roll attitude of the bike - whether it is just keeping it upright, maintaining a lean through a corner or initiating the lean prior to a corner.

 

BTW I checked during my ride home yesterday - tried some sudden changes of direction (especially at low speed). The initial steering movement is away from the turn and often quite significant too.



#33 Magoo

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Posted 09 May 2014 - 01:01

Countersteering is one of those odd things that is learned intuitively with complete ease, but seems totally counterintuitive when people are forced to explain or discuss it.  

 

I've known lots of riders who were self-taught back in the days before motorcycle riding classes who will swear they do not countersteer. I think we've even had that discussion in this forum a while back. But of course they countersteer; they just don't realize it. 

 

The fastest way to teach riders about countersteering is to take it away from them --  by putting them on a 1F/2R trike or a sidecar rig. After they overshoot the first 90 degree corner by 30 feet and run up over the curb into the neighbor's yard, they will grasp that yes, indeed they have been countersteering all those years. 

 

And then, of course, there is Keith Code's famed No BS bike. This will also clear up the leaning vs countersteering thing.  

 



#34 Ross Stonefeld

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Posted 09 May 2014 - 13:57

Worth it for this YouTube comment alone

 

 

 

 
pure lies.  counter steering is like god.  an invisible nonexistent force unprovable by modern physics´╗┐


#35 Magoo

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Posted 09 May 2014 - 21:34

Best analysis of YouTube comments ever: 

 

 

 

jzb9.png



#36 Fat Boy

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Posted 15 May 2014 - 19:02

Agreed - there is a way to initiate a lean without turning the handlebars. It requires a rotation of the rider's body about the x axis which moves the COG off the centreline and initiates a lean. A bit slow - you can't turn sharply with hands off the handlebars.

 

You must steer away from the corner to roll in then steer into the corner.

There's actually an SAE paper on this. The upshot of it is that to initiate the lean, you steer slightly in the direction _opposite_ of the impending turn. That makes the bike start to lean in the correct direction. Once the lean is initiated, you steer in the conventional manner. The lean angle is what turns the bike, though, not really the steering input per say. It's quite a different thing than on a 4 wheeler.

 

I'd like to see the analysis of the cornering loads of a GP bike. They often enter the corner with the rear off the ground and exit with the front in the air. It's all done through the side radius of the tire and the rear wheel torque lifting/turning the bike. It's pretty amazing to watch when done correctly.



#37 imaginesix

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Posted 08 June 2014 - 16:00



There's actually an SAE paper on this. The upshot of it is that to initiate the lean, you steer slightly in the direction _opposite_ of the impending turn. That makes the bike start to lean in the correct direction. Once the lean is initiated, you steer in the conventional manner. The lean angle is what turns the bike, though, not really the steering input per say. It's quite a different thing than on a 4 wheeler.

 

I'd like to see the analysis of the cornering loads of a GP bike. They often enter the corner with the rear off the ground and exit with the front in the air. It's all done through the side radius of the tire and the rear wheel torque lifting/turning the bike. It's pretty amazing to watch when done correctly.

That's not quite the case, as even while cornering one has to reduce steer angle to tighten the line, or increase it to straighten back up (though the same changes can be achieved by slowing down or accelerating, but the question we're dealing with here is steering). It's a matter of setting the lean angle to achieve the desired turn radius, as you pointed out.

 

A point of confusion (one of many) that causes so much misinformation on this topic is that throughout every point of the turn, the rider must push on the inside handlebar ("push steering"). But the direction the wheel is actually pointing relative to the central axis of the bike may be either L or R during that time. Also, the bike will always, every time, yaw L or R in direct response to the direction the front wheel is pointed. That is, unless the rear tire is sliding, what we call counter-steering in automobiledom. In the bike world, "counter-steering" is unfortunately used interchangeably with "push-steering", which is another source of confusion IMO.

 

So in a right turn, the rider starts by pushing the right handlebar, which causes the wheel to turn left, which causes the bike to yaw left, which causes it to lean right, which causes the self-righting steering geometry to turn right as it tries to straighten the bike back up, which the rider feels as a push against his right hand that he must push against in order to control the lean. So the wheel may point L or R and the bike will yaw L or R to follow, but at every point the rider will feel it as a push against his right hand (in a right turn).

 

If the rider fell off the bike while there was still traction available, the self-righting geometry would turn the wheel into the corner, which would tend to pick the bike back up and send it straight again (sometimes smoothly, often wobbly-ly).

 

Another reason there is so much confusion on this topic is that the inputs to make it all happen aren't noticeable until the rider requires a rapid change of course such as during emergency manoeuvers or aggressive riding. The physics don't change at different speeds, or with smaller bikes, but at regular cruising speeds the rider is applying these inputs intuitively since the force required to turn is too small to raise awareness of what's going on at the handlebars.

 

Balancing a motorcycle is intuitive because it's something we learn to do when we learn to walk, as the same balancing act must take place. If you walk around a sharp corner, you will displace your feet to the outside of your body without even realizing it. Try running around the same corner and these dynamics become much more apparent. Motorcycles steer the same way, by "tripping" the tires out from underneath the CofG and then "catching" the bike again as it leans over, all through the steering. The beginner biker just has to become accustomed to the input through the steering that achieves that same balance that he has always applied through his feet. No new learning is required. This is quite unfortunate, as riders are then very unprepared for handling the bike when they need it the most - during emergency evasive manoeuvers, as the force they must exert on the handlebars is much greater and has to be applied very deliberately.