Motorcycle Ideas

[Mossie]

that it's excessive length would severely restrict it's maneuverability in heavy traffic:

You need an UNO then:


(Someone really needs to photoshop out those wheels!)

Latest version, Uno III with front wheel that flips out for the open road:
http://www.dailymail.co.uk/sciencetech/article-1388074/Uno-III-Streetbike-unveiled-The-transforming-U3-fit-lift.html

[Weaver]

That Uno was discussed quite a bit on biker sites recently. I forget the exact figure, but the front wheel deploys at some quite low speed like 25mph, which begs the question, what happens if you're in traffic that's constantly hovering at about that speed? Does the front wheel keep popping in and out like a trombone, and what does that do to the handling if it's contantly in a transition phase? 

[Weaver]

Don't forget the Avro machines.

Nice one Jon  - nothing new under the sun, eh?

There were lots of experiments in the 1920s when the motorcycle "formula" hadn't yet been set in stone. One of the most famous was the Ner-a-Car:



http://en.wikipedia.org/wiki/Ner-a-Car

[Mossie]

That Uno was discussed quite a bit on biker sites recently. I forget the exact figure, but the front wheel deploys at some quite low speed like 25mph, which begs the question, what happens if you're in traffic that's constantly hovering at about that speed? Does the front wheel keep popping in and out like a trombone, and what does that do to the handling if it's contantly in a transition phase? 

The computer would be able to work it out.  I'm driving a Fiat 500 hire car for work at the moment, it has a fuel saving 'Start & Stop' function (you can turn it off if you want).  If you select neutral, the engine stops, then starts again when you press the clutch.  If you do it too often, the computer disables it.  It can be a little too clever for it's own good sometimes, but it errs on the side of caution.  I think a similar arrangement would work on the Uno III but in reverse, i.e. the front wheel stays deployed if you slow down too often.

Either that, or the gyros should be able to handle it.  Definately needs to be sorted out before it's launched though.  I hope the Uno works & it should but I think it'll have a hard time selling, as you mentioned before, people are suspicious of something different.  Even if it works, doubts might creep in, I've seen quite a few comments on t'interweb from people who are determined not to be convinced!

[Weaver]

You'll probably also have seen weary comments from people who've been reading the bike press for 25 years and who've got used to the regular summer crop of unbuildable, impractical concept bikes from newly qualified design students that are never ever seen again......

The thing with the speed issue is that all your Fiat's computer is doing is switching the engine on and off: it isn't making the wheelbase longer and shorter while simultaneously changing the steering geometry amd weight distribution.....

[GTX]

One for this thread...maybe:




Regards,

Greg

[Mossie]

You'll probably also have seen weary comments from people who've been reading the bike press for 25 years and who've got used to the regular summer crop of unbuildable, impractical concept bikes from newly qualified design students that are never ever seen again......

The thing with the speed issue is that all your Fiat's computer is doing is switching the engine on and off: it isn't making the wheelbase longer and shorter while simultaneously changing the steering geometry amd weight distribution.....

No, what I'm talking about the Fiat's computer is preventing the function that switches the engine on & off from happening.  You were worried about the wheel constantly popping in and out, that's simple to prevent.

[Weaver]

You'll probably also have seen weary comments from people who've been reading the bike press for 25 years and who've got used to the regular summer crop of unbuildable, impractical concept bikes from newly qualified design students that are never ever seen again......

The thing with the speed issue is that all your Fiat's computer is doing is switching the engine on and off: it isn't making the wheelbase longer and shorter while simultaneously changing the steering geometry amd weight distribution.....

No, what I'm talking about the Fiat's computer is preventing the function that switches the engine on & off from happening.  You were worried about the wheel constantly popping in and out, that's simple to prevent.

But the thing is, the bike's wheel is supposed to pop out when the speed exceeds 25mph (or whatever) and then retract when it drops below it. If you're in traffic that's constantly going from 20mph to 30mph to 20mph again in less than a minute, then the wheel is going to be constantly moving back and forth. The computer can't fix that, because it can't see into the future: it can't know whether the 25mph just attained is going to be sustained for the next 20 seconds or the next 20 minutes.

[Mossie]

It could limit it to, say, three times in a minute.  Any more & the facilility is disabled for, say, two minutes.  The designer would need to do some research into how often the bike & the rider could bear it happening & restrtict the operation within those parameters.  Not predicting the future so much, but basing the operation on known conditions.

[Mr.Creak]

But the thing is, the bike's wheel is supposed to pop out when the speed exceeds 25mph (or whatever) and then retract when it drops below it. If you're in traffic that's constantly going from 20mph to 30mph to 20mph again in less than a minute, then the wheel is going to be constantly moving back and forth. The computer can't fix that, because it can't see into the future: it can't know whether the 25mph just attained is going to be sustained for the next 20 seconds or the next 20 minutes.

Simple solution?
How far is the throttle open as the bike exceeds 25 mph?
If it's wide open (i.e. you've wrapped it back to get the wind in your hair visor) then the wheel comes out.
If it's just "bilpped" or only just open then the on-board computer decides that you haven't got an open road in front of you and keeps the wheel in.

[Weaver]

It could limit it to, say, three times in a minute.  Any more & the facilility is disabled for, say, two minutes.  The designer would need to do some research into how often the bike & the rider could bear it happening & restrtict the operation within those parameters.  Not predicting the future so much, but basing the operation on known conditions.

The result of that would be that, unless the rider kept a constant mental time log of how fast he'd been travelling for how long, he wouldn't know whether his bike was going to change shape or not! It's gone from being constantly in a state of flux to changing at irregular, unpredictable intervals!

Simple solution?
How far is the throttle open as the bike exceeds 25 mph?
If it's wide open (i.e. you've wrapped it back to get the wind in your hair visor) then the wheel comes out.
If it's just "bilpped" or only just open then the on-board computer decides that you haven't got an open road in front of you and keeps the wheel in.

Sorry, but it's just not as simply as that. Throttle position doesn't relate to intended cruising speed, but to acceleration. He may whack the throttle wide open from 20mph in order to overtake in a fleeting opportunity then whack it fully shut again three seconds later to drop back into a gap in the traffic.


Take it from somebody who's an ex-despatch rider and a has put a LOT of hours in riding all sorts of bikes: you do NOT want things happening to the steering geometry of the bike automatically in response to simplistic rules. Even automatic throttle adjustments (say in response to speed limits) can kill you if they occur in a corner (they've been tested for real and found to be unsafe). The only way this kind of technology would be acceptable would be if it was rider-controlled: The rider decides when it's safe to change the shape of his bike and pushes a button at his discretion to make it happen.

Frankly though, it's just pointless. You can make a scooter that's as short and agile in traffic as the "folded" Uno that's still perfectly safe at 80mph (I've got one). Equally, you can make a 140mph bike that's almost as agile in traffic as the scooter (got one of those too  ), and all without invoking this kind of expensive, over-complicated and dangerous technology.

[Mr.Creak]

Sorry, but it's just not as simply as that. Throttle position doesn't relate to intended cruising speed, but to acceleration. He may whack the throttle wide open from 20mph in order to overtake in a fleeting opportunity then whack it fully shut again three seconds later to drop back into a gap in the traffic.

Hence my comment on blipping the throttle. If the throttle's open and then shut within a certain time it doesn't "transform".

Equally, you can make a 140mph bike that's almost as agile in traffic as the scooter (got one of those too  ), and all without invoking this kind of expensive, over-complicated and dangerous technology.

Yup: my last one:
http://homepage.ntlworld.com/paul.a.allcock/images/Bike.htm
(but its "little brother", the 6, was much better round town).
But I agree fully on the dangers of a bike that messes about with itself while moving.

[Mossie]

The result of that would be that, unless the rider kept a constant mental time log of how fast he'd been travelling for how long, he wouldn't know whether his bike was going to change shape or not! It's gone from being constantly in a state of flux to changing at irregular, unpredictable intervals!

A simple light on the dash would tell you if it's disabled, the rider doesn't have to remember anything.

[jcf]

Like many bits of gee-whiz technology over the last 100+ years, the UNO is a solution looking for a problem.

[Weaver]

Yup: my last one:
http://homepage.ntlworld.com/paul.a.allcock/images/Bike.htm
(but its "little brother", the 6, was much better round town).
But I agree fully on the dangers of a bike that messes about with itself while moving.

Nice  Mine's a TDM900.

I just noticed something else about the Uno: it's top speed is just 30mph. Why anyone thinks such a low performance bike need such an elaborate transformation mechanism is beyond me: you could ride it constantly in "unicycle" mode if all it does is 30mph...


ANYWAY...


I suggest we drop this now: the point of the thread is motorcycle model ideas, not a technical debate.