Hydro-peneumatic hybrid drivetrain and brake system



Mehrdad Wieske said:
To my Tone,.......I do not care, what people think !
That, frankly, is stupid. People are generally quite conservative when it comes to big changes, and switching from chain-drive to hydraulic drive would definitely be a big one. So selling people a huge new idea is hard enough even if you're slick, well-funded and likeable, and you're trying to do it while being abusive, that's a seriously bad move.
You're setting yourself up for failure by setting people up to ignore your idea because the way you're treating them.


So you want a bike as maintenance free as a pair of skis-

1) they already exist. The single-speeds with coaster brakes that was all I rode until I was 15 never saw any other maintenance than flat fixing and the yearly oiling of the chain and saddle adjustment.
2) rental skis aren't mainteance free. Between each customer they get waxed and the edges checked over. Between every 5-10 customer they get the edges honed. At least once every season they get planed, floated and scratches seen to.
3) it's an unfair comparison. The ski itself is a purely passive piece of equipment, all its environmental interaction is dictated by its inherent materials properties. The ski binding as compared to the bike is ridiculously simple. It has no rotating parts, almost no seals and a very simple task - clamp down and release. Basically they consist of a set of springs, hinges and a few cams.

dabac said:
Production costs - an ordinary drive train has quite few high precision components, apart from the bearings and freewheel/freehub clutch the rest can be pretty much stamped out from sheet metal. I suppose you'd need far more precision engineering in a hydraulic system.

Mehrdad Wieske said:
This is the difference, I am not talking about ordinary anything.......where have bin Disc Brakes for Bikes 10 -20 years- 30 -40 years ago ? Now days I am not gona hit the trails without!

But for there to be a market there has to be a demand. Brakes were easy to develop and sell because there were so many obvious shortcomings in the earlier systems. Drum brakes - overheated at long descents, rim brakes - poor performance in wet, wore the rims out, needed reasonably true wheels. Current drive systems WORKS, so you're facing a far tougher sell.

Mehrdad Wieske said:
I blieve, Gears (Gearbox) are passed, Hydlaulic gears are light and don't brake, no warring out, no Chain SUCK, no Dirty Chains...broken gears, brocken chains etc. resulting broken Colar bones and no fun!
Apart from the bits about chains you don't know any of this. Switching to hydraulic is not a guarantee against things breaking, or wearing out, or ending up at a low weight. To make things rugged and reliable you need careful design and wide margins. To make things light designers tend to skimp on the margins, use lighter materials and more complicated production processes. A requirement for light weight is very often in direct conflict with a requirement for ruggedness and durability.

Besides, how many accidents are caused by equipment failures as compared to those caused by user error?

dabac said:
Seals/ bearings/losses
On a bike seals for the rotating parts are fairly basic, which is OK since they only have to be splash proof. For a hydraulic design they would have to deal with both rotation AND pressure, which in all probability would make them drag more.

Mehrdad Wieske said:
have you ever had a "Rolof Gearhub" in your hands ? Turn that B..ch.this is not sealed...this is braked. People still love that ****! And the Hub is far from perfect

But the rohloff is aimed at a very specific market segment - those who want a low-maintenance (commuter/touring) bike with a decent span of gear ratios. They know the tradeoff and accepts it.
The rest of the bike-riding population prefers the tradeoff between higher performance and a certain amount of maintenance instead.

Mehrdad Wieske said:
I am only comparing the two activities (not the equipments), sommer and winter time ski-slope bikking becomming more and more popular the only missing link to get that really masively going is a mainanence free rentable begginer friendly "RENTAL-BIKES

Ah, so you're not looking for a replacement for the average bike, you're looking for a special rental bike version. That's a quite different proposition.

OK, you have a complete rookie who wants to start riding bikes downhill, do you really think the drive train design will be his biggest difficulty? How would the hydra-drive help him? It can't tell him to shift his weight rearwards before applying the brakes, the difference between a firm and a panicky grip on the bars, or when to bail out or when to ride it through.

Something that does seem to cause rookies some trouble is switching gears, particularly if they have a triple front together with a 7-9 rear. But a way around that which would require far less engineering would be to use electronic servo-shifting systems. You could have a two-button user interface and the bike would keep track of cross-chaining and all that. Heck, stick a cadence counter in there and you'd have an auto shifter.

Or is it just meant to help the guys in the rental shed? They're not concerned with maintenance as such, their concerns are payoff time, the MTTR (Mean Time To Repair) and average repair cost. If your design is 50% more expensive it has to make up for that somehow. Either by breaking down less often , or by being faster to repair. Cheaper to repair would be nice too, but I think that it would be hard to beat the current systems.


Mehrdad Wieske said:
Hydraulic drive is DA Solution, Man ! Don't you think!

Not really. If you're thinking of summertime ski-slope biking I assume most will take the lifts/cable cars uphill, and then do some light DH-ing back down. That reduces the span of gear ratios required considerably. I think a bike with a rohloff/nexus hub (perhaps with a beefed up axle, or a tandem version?), disc brakes and a fully enclosed chain guard would do just fine for that purpose.

If mud is a serious issue internally geared hubs could be combined with shaft drive for a "completely" sealed drive train.

I think a more probable customer segment for a hydra drive bike is a tourer who is looking for the ultimate durability from his bike even if it comes at a cost.
 
dabac said:
That, frankly, is stupid.

You know what? I think "frankly" That Something about my idiea is hurting you where the sun does not shine, and you do not have the balls to call me stupid in my face!!!.....I do not use Falls names! Komm on don't hide your sorry a...
 
Mehrdad Wieske said:
You know what? I think "frankly" That Something about my idiea is hurting you where the sun does not shine, and you do not have the balls to call me stupid in my face!!!.....I do not use Falls names! Komm on don't hide your sorry a...

Your idea HAS some merit, as doing away with the chain would be a nice thing. But spreading insults around at every hint of criticism when trying to introduce a new idea IS plain stupid. And I would do it to your face too, if need be.

But since you're probably just as unpleasant IRL I'm well content that this is as close as you and I are likely ever to get.

YOU are your own greatest enemy as long as you keep acting like this. Heck, with this rude behaviour (which you so handily demonstrated) you wouldn't even be able to sell a fully operational tailwind generator, something every cyclist have dreamed about at some point.
 
dabac said:
Your idea HAS some merit, as doing away with the chain would be a nice thing. But spreading insults around at every hint of criticism when trying to introduce a new idea IS plain stupid. And I would do it to your face too, if need be.

But since you're probably just as unpleasant IRL I'm well content that this is as close as you and I are likely ever to get.

YOU are your own greatest enemy as long as you keep acting like this. Heck, with this rude behaviour (which you so handily demonstrated) you wouldn't even be able to sell a fully operational tailwind generator, something every cyclist have dreamed about at some point.

Ah I see this thread has risen from the dead and the mr Mehrdad is being just as ofensive as ever. Anybody would think he was trying NOT to sell his product.

As for the tailwind generator, any idea where I can get one? It sounds like something I could use.
 
davebee said:
Ah I see this thread has risen from the dead and the mr Mehrdad is being just as ofensive as ever.

You know, in hindsight there are a couple of parts from the OP that I find rather entertaining "...I need an engeenier to caculate my designs...I have thougt of everything.....
If he really HAD thought of EVERYTHING, would there really be anything left for the engineer to do?

Besides, throwing some crude math at the problem quickly shows that the objections pointed out earlier in this thread, pressures, flow rates etc certainly aren't as insignificant as he thinks they are.

davebee said:
Anybody would think he was trying NOT to sell his product.

Yeah, why settle for the trifling obstacles of precision engineering and a conservative industry when one can have a compound challenge by adding an abusive personality to the mix as well :confused:

davebee said:
...As for the tailwind generator, any idea where I can get one?
There is a crude DIY version which is basically a table fan strapped to the rack and powered by a pickup from the wheel, but the one you really want is usually found on the shelf to the right of where they keep the variable gravity front wheels, you know, the ones with the built-in permanent descent ;)
 
This reminds me of something I read not too long ago, I deal with this in software more frequently than I'd like to.

http://worsethanfailure.com/Articles/The_Complicator_0x27_s_Gloves.aspx

IMHO, you want someone to engineer this thing? Make a prototype and prove that it has an advantage over chain. Otherwise you have no credibility.

One thing I've learned (just tinkering out in my garage), you might think you have the greatest idea since bread, but the bottom line is that it might be junk once it's built. Your "design" has no merit. I've had quite a few disasters, but that's how I generally learn, from my own and other's mistakes.

Chain has been standard for years, pneumatics have been around for years. If it had any advantage as drive train for a bike, I imagine that most high end bikes would be hydro-pneumatic today.

Later,
Pete

 
Psychopete said:
This reminds me of something I read not too long ago, I deal with this in software more frequently than I'd like to.

http://worsethanfailure.com/Articles/The_Complicator_0x27_s_Gloves.aspx

IMHO, you want someone to engineer this thing? Make a prototype and prove that it has an advantage over chain. Otherwise you have no credibility.

One thing I've learned (just tinkering out in my garage), you might think you have the greatest idea since bread, but the bottom line is that it might be junk once it's built. Your "design" has no merit. I've had quite a few disasters, but that's how I generally learn, from my own and other's mistakes.

Chain has been standard for years, pneumatics have been around for years. If it had any advantage as drive train for a bike, I imagine that most high end bikes would be hydro-pneumatic today.

Later,
Pete


Just a simple Q. ? Is everyone working for "Shimano" & the co.?
 
Mehrdad Wieske said:
Just a simple Q. ? Is everyone working for "Shimano" & the co.?

Just because we're not "with" you doesn't necessarily mean that we're actively against you.

You have to ask yourself, what is more probable:

a) The big manufacturers are so worried about you and your idea that they have recruited a world-wide network of people commited to putting you down wherever you pop up.

OR...

b) Your idea simply hasn't enough merit to anyone else but you.

And until you learn to accept criticism gracefully and to evaluate your own ideas in a wider perspective you're not going to be an economical threat to anyone but yourself.
 
I have long thought about a better way to handle the gearing on a bike, and am convinced that a CVT style transmission might be the best approach. Fairly lightweight, infinite gearing, and relatively cheap to implement. They are widely used on snowmobiles and atv's, and have begun to appear on cars.

The real downside of CVT is that it depends upon friction - the friction of the belt on the cones. Splash a bit of water or mud on the belt or one of the cones, and you're stationary. Perhaps a V shaped chain with ridges on the side to engage ridges on the cones...
 
JohnO said:
... Perhaps a V shaped chain with ridges on the side to engage ridges on the cones...

I'm sorry to rain on (part of) your parade, but that wouldn't work if you want continuous adjustability. The spacing between the chain ridges would have to match up against the spacing of the cone ridges. But the cone ridge spacing would be dependent on the distance from the center.
I suppose one could set up some sort of stepped interval, but I predict nasty crunching on gear change....

Maybe one could have a finely ridged belt, and then the cone surfaces covered with a polyurethane coating tough yet soft enough to provide grip for the belt.
 
Yep, that"s the one weakness, and that's why they use a fricton belt on CVT transmissions. Couldn't maintain a constant spacing between the ridges.


OTOH, the entire unit could be sealed. Some motorcycles have the chain entirely encased so it can run in an oil bath - no reason a lightweight enclosure couldn't be developed to keep water and mud off of the belt and cones. It wouldn't have to be entirely waterproof, just enough to deflect whatever was being splashed around.


dabac said:
I'm sorry to rain on (part of) your parade, but that wouldn't work if you want continuous adjustability. The spacing between the chain ridges would have to match up against the spacing of the cone ridges. But the cone ridge spacing would be dependent on the distance from the center.
I suppose one could set up some sort of stepped interval, but I predict nasty crunching on gear change....

Maybe one could have a finely ridged belt, and then the cone surfaces covered with a polyurethane coating tough yet soft enough to provide grip for the belt.
 
JohnO said:
Yep, that"s the one weakness,

Years ago I was toying around with the idea of sort of a shaft drive worm gear, where you'd move the little cog closer or farther away from the circumference according to what ratio you wanted. I was really pleased with my line of thought until the impossibility of achieving a gradual increase in the number of cogs eventually dawned on me....

JohnO said:
OTOH, the entire unit could be sealed. .. It wouldn't have to be entirely waterproof, just enough to deflect whatever was being splashed around.

That's an intriguing thought. I wonder where you'd end up size-wise though, if pedal and rear stay spacing would actually allow for such a design. And what are the forces involved, how much does it take to force the cones together?
Any guess about what tension the belt runs at?