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The gripshifr puts me off. Could they not have a cable operated trigger on each side of rhe bar to pull the gearbox in opposite directions?
There is a left hand right hand Rohloff but it looks rubbish.
I've seen someone used a sprung carrier on the down tube to utilise a more traditional shifter.
Nicolai keep saying the'll develop one.
I'm surprised one hasn't been done and or an electric shifter.
Loads of companies have had a go at producing trigger shifters for Rohloff and Pinion, they never seem to make it to market. Not as simple as you might think.
I don't think its simple, I do think that the number they would have to make is so small that no one is really interested
The gripshifr puts me off. Could they not have a cable operated trigger on each side of rhe bar to pull the gearbox in opposite directions?
Ah, now there's me thinking it was an automatic! i.e. you pedal and it shifts up, stop/ease off/strain and it shifts down etc. duh
Ah, now there's me thinking it was an automatic! i.e. you pedal and it shifts up, stop/ease off/strain and it shifts down etc. duh
A mate thought that about XTR di2 😆 got back from a test ride (of not insignificant length) and pronounced it shit as it didn't change gear by itself the whole way round...
There is a system that does that NuVinchi I think
Personally can't wait for gearboxes to be mainstream. I hate derailleur systems and as we get wider and wider cassettes they are just getting worse.
A derailleur system, when it's brand new and lubricated in perfect conditions, will be about 1% more efficient than a Rohloff. Difference is, the Rohloff will still be as efficient when it's covered in mud, the derailleur's efficiency goes down quite a bit with wear and muck.
my experience was it was efficient under full load pedalling hard, but had extra drag compared to normal setup when just pedalling lightly. It also felt like pedalling through treacle all the time but that's just feel not efficiency
I've ridden Rohloff's for over 10 years. My main MTB has been Pinion for the last 3 and I've got a belt drive Alfine 8 commuter. Of those the Pinion by far has the least sensation of inefficiency/drag. On the Rohloff and definitely on the Alfine there is sometimes a feeling of drag (though it's another matter whether that translates into a loss of power that's material in real world use.
Pinion rides really well. I don't have any problem with the Gripshift. It will cope with being plowed into the odd log (the tensioner just moves backwards out of the way).
alfines and rohollfs are really easy to service. Alfine is just take the cluster out and dump it in a oil bath. I can do one in under 1/2 hr including the time for the excess oil to drain away. drive trains last many times longer. Nor do you get dropped/ flappy chains or missed shifts. I'll exchange that for (a perception of?) drag anyday. The only thing that annoys is the Rohloff shift is pretty slow and clunky.
I believe epicyclics are inherently more draggy and inefficient, chain drives are amongst the most efficient methods of transmission, of course once you slim the components down, start deliberately jumping between sprockets, putting the chain at various angles and introduce grime and moisture then of course durability is bound to suffer, chains and mechs still aren't bad at all IMO.
As mentioned above the old Honda RN01 "mech in a box" concept probably had far more mileage in it than was ever pursued, and of course patents and IP are in place to ward off anyone looking to unearth that idea now. I could certainly see the appeal of a Di2 operated 11+speed enclosed derailleur type gearbox for modern trail bikes...
There were quite a few ideas from the mid-late 90's/Early 00's that it would be interesting to see developed further today.
SRAM do an automatic hub gear for town bikes IIRC... But it's only 3 speed, and made by SRAM 😕 So...
Considering the vpp in protection has expired I'd imagine the Honda stuff will expire soon too.
The Cinq5 trigger shifters for Rohloff are very good - I use them all the time.
I'd imagine the Honda stuff will expire soon too.
Afaik Honda released all claim on the patents , it wasnt the program they were running that was important
MTB is finally shedding all the throwbacks from road bike but the rear derailleur still clings on.
Simple, sure. Cheap, that too but it is pretty archaic and hangs in the path of many hard and sharp things, just waiting to give it a kicking.
As other have said, with the onset of wide range cassettes, the need for gearboxes (electronically assisted not that two cable grip shift nonsense) is becoming more of a reality. Companies just need to sort some of the weight and size issues. I for one am lining up when Shimano or SRAM finally get their act together.
But I am surprised that Shimano, a company who also known for their geared fishing reals and hubs, haven't figured something out already.
saw a road bike near London Bridge the other day with what looked like one of these gearboxes.
[url= https://google.com/patents/EP1630091A1?cl=ru ]interesting[/url]
Ref country code: GB
Free format text: LAPSE BECAUSE OF NON-PAYMENT OF DUE FEES
Effective date: 20130706
Seems Honda may have let some of the patents lapse...
The Honda program was spread across more than one platform
I have two types of gearbox sat here in the works one is based on that information. and one is wireless
Are they likely to become consumers projects?
I'm fairly sure I saw something on his instagram ages back.
cookeaa - Member
I believe epicyclics are inherently more draggy and inefficient...
The answer is to grow a set of legs and either singlespeed or get a Sturmey-Archer 3 speed which wastes very little energy. Low gear for hills, middle gear (direct and efficient) for normal, and top gears for downhill/tailwinds. Sorted. 🙂
I also have an Alfine and a Rohloff. I haven't used the Rohloff for several years now because I didn't like the feel of it - it felt like I was grinding coffee in the lower gears. The Alfine is lovely. Mainly used for rides that include a mix of road and offroad. I grew up on 3 speeds so I don't find the method of changing gear unusual.
A centrally mounted gearbox is an idea whose time has come IMO. The problem with adoption is you can't do a retro fit, you need to buy the whole bike.
It has always surprised me no one has come up with a way to enclose a derailleur system. Fully enclosed in an oil bath, it would be very difficult to find anything better.
I for one am lining up when Shimano or SRAM finally get their act together.But I am surprised that Shimano, a company who also known for their geared fishing reals and hubs, haven't figured something out already.
Well I have bought one Rohloff in my life, 10 years ago now, I probably won't ever buy another one, or what I should say is I probably won't ever need to buy another one. I'm sure that Shimano could come up with a gearbox that had the same reliability and lifespan but I'm not sure they or many others in the bike industry want to get into making expensive things that last. Such things in the end benefit the consumers pocket not their own. It might work as a business model for small companies like Rohloff but for the big boys this is an industry reliant on ever changing standards and obsolescence.
Alfines go on for ever if serviced properly as well.
As an aside if you find an alfine draggy take the cluster out and degrease it then give it a bath in ATF - they run with less drag then but it does need redoing ever year or so.
Alfines go on for ever if serviced properly as well.
The 8 speed may be reliable but if you look just on this site regarding the 11 speed they don't have the same reliability.
Pinion touring bike picked up today:
[url= https://c3.staticflickr.com/9/8632/28634279210_0b458ff034_z.jp g" target="_blank">https://c3.staticflickr.com/9/8632/28634279210_0b458ff034_z.jp g"/> [/img][/url]
😉
Is that bike for some kind of giant or do you sell head tubes by the yard 🙂
Really nice bike that (apart from gate sizing). Well done Ben!
Looks like modern technology meeting classic design seamlessly, lovely!
A centrally mounted gearbox is an idea whose time has come IMO. The problem with adoption is you can't do a retro fit, you need to buy the whole bike.
And the size and shape of the box restricts suspension design.
Really though I think the issue is weight - I'm pretty sure Pinion adds about 1500g over a 1x11 set up. That's not such an issue for me at 80kg but more so for lighter riders. My experience suggests that Pinion have got the longevity sorted so lifetime cost is going to be lower than a conventional setup.
It has always surprised me no one has come up with a way to enclose a derailleur system. Fully enclosed in an oil bath, it would be very difficult to find anything better.
That was the Honda box wasn't it? You've still got the box, the oil bath and the additional gubbins to get the drive out of the box so you're still adding weight.
The advantage of Pinion style spur gears is longevity and reliability - I'm not convinced you'd retain that with a mech in a box.
So, why not have a CVT style gearbox system with two opposing tapered rollers with one being the input the other the output and some kind of flexible rubber belt joining the two?
There is a CVT hub available - the nuvinci. Can even be had with electronic shifting.
The nuvinci hubs are excellent on city, commuting, cargo bikes but are heavier than Rohloff
The cvt in operation is excellent stepless, shifts under load and would be excellent if available in a gearbox
Gearboxes dangerous 😉 look what happened to this guy.
So, why not have a CVT style gearbox system with two opposing tapered rollers with one being the input the other the output and some kind of flexible rubber belt joining the two
The problem with most CVTs is that they're not very good at low speed, high torque applications - and rubber belts are draggy. The NuVinci does it with ball rollers and a special non-linear transmission fluid.
That was the Honda box wasn't it? You've still got the box, the oil bath and the additional gubbins to get the drive out of the box so you're still adding weight
The second one - the first one was an ingenious system using reciprocating linkages which was an absolute nightmare to make.
Is that bike for some kind of giant or do you sell head tubes by the yard
Thanks - this customer wanted a more classic geometry, with a very slack seat tube and higher bars.
So, why not have a CVT style gearbox system with two opposing tapered rollers with one being the input the other the output and some kind of flexible rubber belt joining the two?
These have been made before sadly the requirement is quite a bit of pressure between the intermediate roller input and output
1. on top of this you need to somehow disengage one of the rollers to slide it sideways or the actuator must overcome these forces and shunt something sideways, never a good plan or have some kind of linkage to bring it in to contact precicely ,and keep that rigid too ....you see the cascading effect the gearbox is already getting complicated and stiffer and heavier
2.1 the belt usually sits between an input pulley and an expanding and contracting pair of pulleys which are a further distance apart in low and closer together in high this means as they pinch the drive belt it rides up the tapered cone pulleys altering the ratio
CVTs are normally run at constant speed also its very odd hearing a car just revving its tits off/droning along
2.2 the pressures involved mean a stiff casing is required for the bearings and to keep those things locked down tight
2.3 to run a belt on rollers would twist at its extremes and you need to deliver torque , to get enough tension on the belt go back to 1. and see how much tension you actually need to put a belt on a smooth pulley to transmit the torque to move a bike they are pretty shite at torque low down which is what legs make , its a tiny little highly loaded belt and no you cant put scerations on the belt - a la gates because it tapers
3. soft squidgy transfer rollers have been tried and eat themselve and deposit themselves on either the drive or output roller very rapidly causing wear
4. hard as **** transfer rollers have been tried and cost more than a real live baby jesus to produce.
5 transfer fluid has been tried, this is not the same as Atomatic transmission fluid.... Oils like Shell morlina have a very high pressure rating but do not lubricate at all . Traditional Gears tend to work in a very basic sinusoidal way to a degree they only transmit power over a pressure angle on the gear each tooth might be 15 or so degrees a bit like a cam and that pressure needs lubricating as the faces slide across one and other (this isnt a cover all of all types of gears as there are many types that comes with pros and cons but the pinnion we took to pieces here and stored for [s]scrap[/s] future examination now i know its faults .....why i mentioned the oil is that mechanics tend to go oooh arrgh ATF its exactly the same stuff....er no its not and so you end up with loads of completely ****ed worn out bits for anything that relies on traction fluids ...i can tell you this because every colchester chipmaster thats ever had one of these morons near it now has a knackered Kopp VARIATOR
which brings us to
the Nuvinci which uses a special traction fluid which is effectively a miniature KOPP variator from the 50s as used in lots of machine tools and just like machine tools they weigh more than a ton, maybe ...well not at all but they arent going on weight weenies any time soon
finally Oils which provide traction are like ethanol if theres a crack in the casting they will find a way to get out and then you need to start sealing things to take this into account
i might do the goods and bads of Pinion tomorrow i ****ingn hate writing stuff
ps good job Ben It seems gearboxes are the future of COMMUTER type bikes it would be great if someone made a hole in the top so you could just put an extra gear in and connect the motor instant e bike......
might do the goods and bads of Pinion tomorrow i ****ingn hate writing stuff
Write it - I'd be interested.
bencooper - MemberThanks
Sorry, I didn't mean to be rude. I like the bike from a practical point of view just the headtube made me think it was BIG.
Write it - I'd be interested
Me too. My test ride on 18 bikes demo has left me wanting a pinion bike. Weight and the shifter are the common complaints and for me the benefits outweigh these. The P.12 has a 600% range, when 12 speed Shimano XT comes out it won't match that and will probably weigh even more 🙂
Sorry, I didn't mean to be rude.
I didn't think you were 😀
It's not conventional geometry - 68deg ST for instance - but it works for this person. And I liked it when I test-rode it too.
Ben have you ever fitted a nuvinci 360 to a Brompton? (I've a hub left over from my cargo bike and have been considering using one of your 135mm rear triangles)
Not yet, though will do a belt drive version in a couple of weeks. I can't see any reason it won't fit, might need a little bogging of the tensioner, that's all.
Ben, excellent I'll be in touch to order some bits when I'm back from my travels