Survey on new gear system

[vectr]

I've read about similar devices before. Specifically the "Deal Drive" which was actually an automatic transmission (it was torque sensitive I think)

If you can make it light and reliable, maybe combined with an enclosed chaincase it could have a role on city bikes, I guess.

Or maybe not. Best of luck with it

Thanks for you feed back and good wishes.

Actually, I expected the greatest resistance to be from those pointing out how it has been tried before. As you see from the Deal Drvie, prior iterations were hugely complicated, and so heavy and expensive. I believe my design is viable because it is simple, and so light and inexpensive to produce, while eliminating chain drop, but not sacrificing performance. I think with some development it can deliver on these. But, yes, reliability is key.

BTW, mine is not automatic. Gear changes are under the rider's control.

At this point I am judging interest, and looking for problems. So far, no problem mentioned so far seems insurmountable. As to interest, we're discussing it, and I have valuable feedback from the survey.

So, if you haven't already, please take the survey.

 

[Dogtrousers]

Survey done.

As far as I've read it was -as you say - weight & complexity that killed the Deal Drive.

Practical thoughts. You need to figure out your target market. I can't see it working for the sports market for a variety of reasons. Maybe for folders? You could increase the gearing range delivered by an existing hub gear. (If it works that is!) But you still need a chain tensioner.

Aesthetic thoughts: Sadly you still need a chain tensioner of some sort which is pretty ugly. From an aesthetic point of view I think the loveliest deraiileur was the Campagnolo Cambio Corsa from the 40s, where the wheel moved. But that's neither here nor there.

derailleur shifting is used on everything from £20 argos or tesco things to the very best £10,000 pinnarelo carbon beauties used by the likes of Froome and Wiggo etc and they work perfectly
Cheers Ed

Derailleurs aren't ubiquitous. There are thousands of hub gears out there, and there are bottom bracket gearboxes too.

 

[Sharky]

This thread has made me think. Do we need a variable chain wheel ? One of my bikes is a single speed and I get round my usual routes with no problem, well for most of the route. In the 60's, I rode a 10 speed. That's a front double and a 5 speed block. Again no problems.

Now we can get 11 speed cassettes or 14 speed hubs and I've just googled a variable hub gear http://www.fallbrooktech.com/cycling/n360 . Doesn't this give us enough gears?

If we dropped the front changer and multiple chain rings, it would save weight and simplify gear changes. Just go up then down. No need to jump up to the big ring and drop to a lower sprocket at the same time.

Perhaps the problem to research is not how to make gears more intricate, but to come up with solutions to overcome poor chain alignment with 11 speeds or to make hub gears lighter and more responsive.

There is also things like the sram 2 speed automatic. If this was say a 10 speed automatic, just think what it might do for the general cyclist!

But keep up with your research. If nobody experimented, we would still be on ordinaries!
Keith

 

[young Ed]

The 4 components which move are gear segments with five teeth, but yes, the rider shifts to move them radially toward the periphery or the center to effectively make a larger or smaller chain ring.

Tell that to Andy Schleck in 2010.

right got you know on how it works.

what happened with Schleck? chain hopped off and he slipped and smashed his knee?

without a power meter i can't be sure but i would guess that i put a fair bit of power down on some of the southdown climbs round here (climbing is my favorite) and so long as i change to the best gear for the climb i have never yet heard a whisper from my drive chain on anything from a £150 cheapo hybrid to a pretty nice £800 roadie with third from the top components
Cheers Ed

 

[young Ed]

not stopping you from working on this concept but i wouldn't buy it personally

one thing to consider would be cost, how would it compare to something such as the top of the range shimano durace kit
Cheers Ed

 

[young Ed]

Derailleurs aren't ubiquitous. There are thousands of hub gears out there, and there are bottom bracket gearboxes too.

true, how often do you here of a hub gear or BB gearbox or a belt drive hopping off? they are mechanically complex so when they do go wrong it is a specialist job to rebuild them
i was just saying derailleur as it is all i have had experience with and it is the first one that popped into my head
Cheers Ed

 

[byegad]

I'd forgotten this 'innovation', at 63 I think I've seen it only a couple of times before! This one does look neater and so lighter than earlier iterations but would need to be tested thoroughly before I'd go for it on one of my trikes. However unlike several other innovative solutions that come around every so often it looks like it may well actually work.

As has been pointed out the 'square' nature of the chain err wheel needs to be addressed, possibly by making it 6 or 8 rather than 4 corners.

 

[young Ed]

given i am 15 year old and mad and don't mind pushing a bit but i think i could quite happily ride on 5 or even 3 gears and many people are all about the compact or double chainsets so i can't see many people seeing the attraction of more than 3 chainring sizes

also as you are always running on the same teeth they will wear out a fair bit quicker than a normal chainring that is only being used say 50 or 30% of the time so are these teeth replaceable as cheaply, quickly and easily as a normal chainring, could your average bike enthusiast do this job with minimal tools and knowledge
Cheers Ed

 

[byegad]

Ed replacing one ring every x years is as cheap, or expensive, as replacing 3 every 3x years. OK the maths is a little more complex than that but we all ride one chainring much more than the others and so replace that one a couple of times before the others are replaced, but it averages out.

As to riding with a limited number of gears, you obviously don't ride the North Yorks Moors where a hill isn't a real hill until it's steeper than 20%. I would happily run 81 gears on my lightest trike ranging from 8" to 80" purely for the NYM.

 

[mickle]

Let's have a go on it?

 

[albion]

Not sure what you mean. Nothing 'jumps' the chain; sections expand when they are not engaging the chain.
Let me know if I did not understand correctly.

...but it should change gears no matter the load since the gear segments change radial position when not engating the chain. ...

That answers it, adding complexity but eliminating that problem of changing gear under load.

With reliability it could be useful for leisure, commuters and tourers.

 

[Stephen C]

One concern I would have, is if you have it on a big ring setting, and stand up out of the saddle (to get up a short climb, for example), all of the weight of the rider and power they are trying to transfer will be put on one or two teeth, and one or two links of a chain. I could be wrong, but it seems to be asking a lot of a small number of components.

 

[vectr]

But keep up with your research. If nobody experimented, we would still be on ordinaries!
Keith

Thanks for the encouragement. I am pleased this is generating discussion. At least it is not (to some anyway) obviously stupid. (To others, well, . . )

 

[vectr]

You seem to think chain drop is some great, frequently occurring, disaster for cyclists. It isn't.

As I said, a 'solution' looking for a problem...

Not a huge problem, but not no problem. But addresssing chain drop is not its only advantage. If run on front and rear it would be much lighter than current systems. This model now weighs 525g compared with the 450g Shimano rings/derailleur it replaced, and I am sure VECTr can be produced at 20% or more reduction in weight. I don't know offhand how much a rear casssette and derailleur weigh, but I am guessing more than 450g. The rear version would weigh as much or less than this model.

But, hey, it is obviously not for everyone, or every biking application. Others have suggested commuters/city biking. I am thinking that market might be more open to the unconventional.

 

[vectr]

given i am 15 year old and mad and don't mind pushing a bit but i think i could quite happily ride on 5 or even 3 gears and many people are all about the compact or double chainsets so i can't see many people seeing the attraction of more than 3 chainring sizes

also as you are always running on the same teeth they will wear out a fair bit quicker than a normal chainring that is only being used say 50 or 30% of the time so are these teeth replaceable as cheaply, quickly and easily as a normal chainring, could your average bike enthusiast do this job with minimal tools and knowledge
Cheers Ed

I am sure they could be built with tiny hex bolts that anyone who can turn a wrench can replace.