[Closed] Gearbox Fans/Haters: What if...

IF there was a gearbox drivetrain that Had a decent trigger shifter Would you buy it?

IF there was a gearbox drivetrain that:
- Weighed less than a derailleur system
- Shifted as well as (or nearly as well as) a derailleur system
- Had a decent trigger shifter

it weighs less...well I never cracked that one

I don't like triggers. the alfine comes with a trigger and shifts almost as well as a dérailleur , I changed it to a nexus twistgrip. Rohloff is only a small amount heavier than a 3x9 drivetrain and has greater range than a 1x11

IGH also have other advantages. shifting when stationary, never a dropped chain, silent in use ( apart from a whine in the lowest 7 gears), longevity and believe it or not cheapness. for me the rohloff has paid for itself by now in reduced drivetrain costs. rings and chains last longer and replacement is a chanring and a sprocket and chain.

I love them.

The rohloff shifting is perfect in use but feels horrid. thats a small price to pay for its advantages

Buy me a Deviate and I'll tell you in a month.

You don't notice the rohloff weight and I guess the drag on a tandem. But on a regular bike it drags and is heavy/kills the ride of the bike by its point mass.

I have had mine on 3 bikes and it now lives on my fatty where I can live with its downsides.

For me the shift would have to be smoother -its very clunky.

The weight would need to be less or more spread about the bike

And it should not drag - and I don't care how many tests you present in a riding comparison on the same bike set up there is noticeable drag between a we'll set up 3*9xtr system and the rohloff... Now wether it's system drag or the fact the wheels hanging up more due to the high mass concentration it is slower.

I want to like them. Hence why I bought one....I've had an Alfine.8..it dragged even more. My strumey 3 speeds are the least draggy but achieve that at expense of sealing

Aye the shift on a rohloff feels awful. Never misses a shift but its feel is horrid.

My alfine is not draggy at all - but it is degreased and runs on an oil bath and has done a lot of miles. the Rohloff is still running in and is getting more free but it does feel a little draggy. I think tho they feel worse than they are. something to do with the takeup? epicyclics will always have some drag tho but a perfect chainline helps reduce the overall drag

Its not for racers but its great for touring.

It'd have to be within a couple of percent on drag for me.

Not really a lover or hater - just have no interest in gearboxes at all, or rather can't see why some people get so excited about them.

My Alfine was as God designed and it's draggy I can see how oil bath helps.

Yeah if I was doing some silly tour it would take alot for me to look past my rohloff (which is well run in and has had several flushes and oil changes over the years )

But they are not the magic bullet some would have you to believe

To get me to buy one you'd have to make it have much less drag and also give me a shitload of cash.

If I had the latter I'd probably get a gearbox hardtail with an enclosed chain - always wanted a mudproof bike.

how do the pinion gearboxes compare in the draggy stakes?

Bikeradar thought subjectively it was much less draggy than Rohloff. They had this picture of it:

[img] [/img]

Which makes it look like that it's just two gears being used and not a planetary system, which should really help with drag. Of course there aren't any gears meshing in a derailleur system...

I remember being in a bike museum somewhere in France and they had a bike there with a hub with two gears where you pedalled backwards to engage the lower gear for going up hills. Seemed inspired 🙂

Liked the idea of the Deviate until i read their marketing

...and saw the price as well of course

Still like the look of the Pinion, just can't think of a good reason to get one. The nice thing about derailleurs is that if anything goes wrong on a ride you can just singlespeed it. However I can't imagine anything ever going wrong with these systems, they just look too solid

I tried a pinion on a taniwha and decided against it because:-

The lag in the gearbox freehub was 30°. Way too much to allow me to clock the cranks for the technical riding I like to do.

The pull/pull cable doesn't index in the shifter and while it never missed a shift, it felt vague.

I didn't like the twist shifter.

The lag in the gearbox freehub was 30°.

Yep the time between moving and engaging on rohloff is somewhat urgh. But I've learned to live with it.

Molgrips - the rohloff pays for itself in lower drivetrain replacement parts over maybe 10 000 miles. Instead of 3 chainrings and a cassettte and chain ever couple of thousand miles its a chain every few thousand miles and a chainring and sprioket every second chain. chains last longer as they are not sideloaded and can be worn much further with no adverse effects on shift. I think I am into profit now on the tandem

I don't notice that trailrat at all. the alfine is "soft" on takeup tho. I shall go and check how many degrees to take up on both

What would make me buy one?
Having enough money.
Needing a new bike.

I test rode the zerode and got one well with it.
Maybe a bit of drag.
Twist shift I can live with along with learning how the box shifts, which didn't take long.

In short if I can afford it my next bike will have a pinion gearbox.

My Alfine 8 eventually stopped being draggy, but that was about two thirds of the way through its life span lol (greased, not oil)

Rohloff is about 2-3 times the slack compared to my pro 2 hub about 10 or 15 degrees at a guess between engagement points. Not something I ever notice tho

Its definitely advantages and disadvantages. I have a dérailleur on my good light MTB and will keep it but the alfine is on my winter mtb / commuter and the rohloff on the tandem

Advantages with the rohloff are shifting when stationary, never drop a chain, no chain slap, never miss a shift, able to go from top to bottom gear with one twist and vastly improved drivetrain life. dérailleur is crisper shifting, better weight distribution and maybe a bit less weight overall depending what is replacing and more efficient

But over all the key thing to me is the rohloff is indestructible on the tandem. No other hub is. Its guaranteed for life and if it breaks rohloff will send you a new hub free of charge anywhere in the world. Previously we just mashed hubs. the only other hub worth having on a tandem is the chris king tandem special - very rare and expensive.

I’d have a zerode if they could get the price down to sub £3k for a full bike.
It looks like a perfect bike for me and my hamfisted mechanical skills.

Edit: what would I sacrifice for that? Probably if it weighed up to 33-35lbs would seem a reasonable weight penalty for the gearbox. Reckon I could cope with the gripshift.

the rohloff pays for itself in lower drivetrain replacement parts over maybe 10 000 miles

Not bothered by that. And who the hell replaces all three chainrings when they do their chain and block? I change a little ring every two or three years (but now I've got a steel one) and all my middle and big rings are from 2007!

My point is molgrips is that over the years its a cost saving overall.

The cash comment was because to buy a new bike I'd need a pile of cash right now. I can't offset the cost against the next ten years 🙂

Quick question regarding the benefit of changing gear whilst stationary. Do you ever get caught out when riding a bike with regular gearing? Can you change gear whilst pedaling or do the cranks need to be still?

I would pay more for a gearbox bike than I would for a derailleur equipped bike, because I’d expect the gearbox to last longer, also chain/ring/sprocket lasts longer so will eventually be cheaper to run.
In a perfect world, there would be a range of shifters available, trigger/twistgrip/dropbar/barend.
Im not convinced that a small amount of drag matters that much (for me)..
My mate has an alfine 11 equipped bike, if you spin the rear wheel there is obvious drag compared to my cx bike (dmr revolver rear hub), but it doesn’t seem to make any difference in the real world.
If one was available that retrofitted a bike with a standard bb, then yes, id consider it.

Pronounced pressure off to shift more so than derraileurs but not stationary cranks

Static shifting .... If you get caught out is good. Again can see benifit a on tandem or tourer can take it or leave it on my mtb

Quick question regarding the benefit of changing gear whilst stationary. Do you ever get caught out when riding a bike with regular gearing?

Yes. I only have one bike left with dérailleurs and it takes a while to adapt. I often try to shift when stationary and / or stop in a high gear / shift when coasting to a halt. takes a while to get used to it again. I do love the crisp shifting tho

My alfine 8 freewheels as easily as a front wheel - its when pedalling it drags especially in the lowest or top gear. If his alfine drags when frewheeeling something is wrong. Nothing is engaged when freewheeling

It’s a very small amount of drag tj, you would never notice it riding, its only when you spin the rear up and let it run down that you can see it.
He took it back to the shop he bought it from, the owner is a big fan of igh and has had several of his own, he reckons that my mates one rolls better than the majority of alfine 11s.
Also, its worth noting that it’s done less than a thousand miles, my hubs have done several times that.
Also worth noting, it wouldn’t put me off buying one.

For me the biggest downside (linked to cost) is the fact they’re integral to the frame. I rarely keep frames long enough to justify that kind of outlay. At least with hub gears the wheels can move between bike frames as I change/upgrade.

I’m a real fan of hub gears for certain bikes (winter/rigid/hack/commute) but can’t see me ever getting a gearbox.

I remember being in a bike museum somewhere in France and they had a bike there with a hub with two gears where you pedalled backwards to engage the lower gear for going up hills

The Sturmey Archer S2 Duomatic is currently available and does exactly that and for just £60. It does however weight 1KG

IF there was a gearbox drivetrain that:
- Weighed less than a derailleur system
- Shifted as well as (or nearly as well as) a derailleur system
- Had a decent trigger shifter
- Fitted on your current bike

Would you buy it? How much efficiency would you give up? How much shift quality would you give up?

Biking and efficiency is crucial.
Road biking: I would hate to give up ANY efficiency. No idea about the numbers. But 3 % less efficiency would be really bad.

MTB: guess 3 % less efficiency would be still o.k.. Shift quality shouldn't suffer - or even should be better.

Maybe if rich enough it would be a bike specifically for filthy conditions. I wonder what other design features it could have, if custom made? Nice stable position and perfect balance for those sliding moments would be important.

martymac - If one was available that retrofitted a bike with a standard bb, then yes, id consider it.

This makes no sense, what you're saying is you'd consider a poorly designed, highly compromised version but not a good one.

What you should be saying is, wouldnt it be good if all frames came with a gyneric bb / gearbox mounting system so you could choose to run whatever drive system you wanted.

Olsen bikes [url= http://olsenbicycles.com ]http://olsenbicycles.com[/url] are leading the way with that in some respects... Pinion as standard but with the option to run a threaded BB.

[img] [/img]

Oh and as some one with a singlespeed and an alfine and is lazy, I'd happily have a gearbox and I'd especially like the wife's bike to have one.

3% inefficiency on the bike is nothing compared to the inefficiency of my body.

3% inefficiency on the bike is nothing compared to the inefficiency of my body.

Absolutely right.
But, problem: our sensors are so good and our power output so low that we right away feel if the bike has 3% more friction...

Not sure about the numbers, but with road biking: 3 % worse would kill this option for a race biker!

martymac - Member

It’s a very small amount of drag tj, you would never notice it riding, its only when you spin the rear up and let it run down that you can see it.
He took it back to the shop he bought it from, the owner is a big fan of igh and has had several of his own, he reckons that my mates one rolls better than the majority of alfine 11s.

I guess the 11 has tighter seals than the 8 I am used to given its an oil bath not grease as standard.
Certainly on the 8 none of the internals are engaged when freewheeling so there is no extra drag

Went to IGH in 2003 with a Rohloff to avoid wear and tear issues from local clay/grinding paste.

Currently have
2 x alfine 8
2 x alfine 11
3 x Rohloffs

I have previously outlined the benefits and the bombproofness of the Rohloff and my only criticism and it's minor, is the weight at the back wheel, which you do accommodate too over time.

However I've had a Pinion on a Nicolai for just over 12 months and I would rate it as good as the Rohloff but with the advantage of having the weight centred.

The sooner someone can get these down to a more wallet friendly price the better, for your average mountain bike person the advantages are just too good for vertualy no functional compromise, except if you must have trigger shifters.
As an aside the Nicolai frame with Pinion worked as cheap a as a frame and Rohloff purchase I made back in 2009:-)

I see the future for Mtb's where frames all come with a standard interface for your choice of gearbox with choices from 2-3 gearbox manufacturer's. Although this would probably create another standards frenzy.
Would be surprised if Shimano weren't working on something with their experience around the Alfine.

Podge, you’re correct, it makes no sense.
What i mean is, im completely open to the idea of a gearbox but have no intention of buying a whole bike in the foreseeable future.
Unless i get a big payout for my busted leg of course.
Edit: those olsens look excellent, and reasonably priced.

andreasrhoen - Not sure about the numbers, but with road biking: 3 % worse would kill this option for a race biker!

They aren't aimed at road race bikes though are they so that's a pointless argument.

IGH are virtually standard fitment on euro bikes above the bottom end of the market

There used to be someone blueprinting and lightening rohloffs - is that still going?

jes - Would be surprised if Shimano weren't working on something with their experience around the Alfine.

SRAM have experience of internal gears at the front and rear. I think the Hammerschmit had potential but it wasn't thought through properly.

For me it would be the drag issue (or even the perception of it). I'm skinny and have the power output of wet string, so anything like that is immediately noticeable (I'm amazed at how much difference new -v- old & knackered bearings in jockey wheels makes!)

Weight is an issue, but less of one - especially if its in gearbox format and centre/low like a Pinion. The reduction in unsprung weight on a full sus and lack of dangly bits to clout would probably offset any pure mass gain.

Shifters - happy with gripshift or trigger, but it needs to feel positive. 'Click' in the shifter, not at the end of 5' of wire.

One "inefficiency" that bugs me about Pinion bikes currently - you end up with 2 freewheels - one in the 'box, one in the rear hub. That's gotta be excess weight? I'm not a fan of a permanently moving chain on an MTB (you can imagine the crashes!), so working out a way to ditch the internal one would feel like an improvement.

I happened to bump into Ben Jones from Deviate a few weeks back on my local trails and had a good look at the bike. Looks very well sorted. Barring cost (at the mo) I'd love one, and a much more interesting way to spend £5k than a blinged Santa Cruz or an HB160. I can't help but feel that if you were a high mileage rider who could afford the one-off upfront cost you'd probably do quite well over time through not having to replace chains, cassettes and smashed up mechs.

Weight and "feel" (drag and take-up) are the biggest things for me. Shifting I can live with provided it is reliable. We have alfine 8 and a few sturmey / Sachs 3 hubs knocking around.

The 3 speeds feel least draggy and closest to the take-up of a regular hub (but have to live with tick-tick-tick as you pedal along). The alfine is quiet but I really dislike that mushy feeling as the clutches engage (have done the Fred Whitton route on Alfine) .
I can see why take up isn't an issue on the tandem, but for my favourite techy climby pedal clocking singletrack I want something that feels as direct as a singlespeed with a Hope hub.

I'm just at the point of making a new mtb frame for Alps in summer. My original e-stay from 2011 is now my commuter and surprisingly still hasn't cracked - a variation on that design would work well with Pinion. Hmmm.....

The PO asked:

IF there was a gearbox drivetrain that:
- Weighed less than a derailleur system
- Shifted as well as (or nearly as well as) a derailleur system
- Had a decent trigger shifter
- Fitted on your current bike

Would you buy it? How much efficiency would you give up? How much shift quality would you give up?

I answered 3 % - as a guess.
Funny that somebody posts this:

They aren't aimed at road race bikes though are they so that's a pointless argument.

I'am not a gear box hater at all.
But I stated my opinion and think it's not pointless at all.

Road and MTB:

Gear-box bikes might have a big future if somebody is able to win a race on them. Right now gear box bikes are niche products.

MTB: there are fantastic new bike designs out there - using gear boxes. But to be commercially a bigger success they need to win a race.

My guess, mtb: 3 % less efficiency will be tolerable if there are other advantages (there are quite some!)

But only if this stays true:

Weighed less than a derailleur system

IHG bikes are only niche in the UK. they are mainstream in most of europe

they are mainstream in most of europe

O.k. - if we don't talk about bikes for sport.

As soon as we talk about "sport" (not only racing):
weight and efficiency will be key. Most mtb bikers do biking as a "sport" and bike in a group.
More than 3 % loss in efficiency might take the fun away from them. This might mean starting to struggle to keep up with the group.

Average power rating of a trained biker is quite low. A three percent difference will be felt right away.
I guess at least...

Might be wrong so.
😉

What would make you buy one? The cash in the bank to be able to afford one....

Massive fan of gearbox systems.

It's all about feel. If you 'feel' that an IHG is draggy, and it's going to annoy you, then it's going to spoil your ride regardless of anything else. Nothing to do with actual wattages or times. If however you don't care, then crack on and enjoy the benefits. Choice is good in this situation.

I reckon 3% is about the same as the difference between using draggy tyres and quick ones. And that's often discussed as something people notice and affects their riding experience.

I have a bike with a Pinion gearbox. I had a demo ride on a hardtail with a gearbox before eventually buying a full suspension bike so to answer one of the questions 'what would persuade me to buy' I'd say simply a demo. The chance to try it out and find that I liked it. A lot.

A Rohloff hub was an alternative but all that weight out back isn't ideal on a MTB so my only hesitation in going Pinion was the price.

Most mtb bikers do biking as a "sport" and bike in a group.

That's me. I'm not the fastest nor the slowest on my average ride and that is no different whether I am on my gearbox bike or 1 X 10.

I should have a second gearbox by the end of the month, a hardtail. I'm thinking of singlespeeding my 1 X 10 so I may be derailleur free by Feb.

I reckon 3% is about the same as the difference between using draggy tyres and quick ones. And that's often discussed as something people notice and affects their riding experience.

Good point. One reason why mtb bikers started to put "fast" tyres onto the back and "grippy" ones onto the front.

@Rubber_Buccaneer

I have a bike with a Pinion gearbox.

great input. Means the Pinion is already very close to the efficiency of an convential 1x11 system or similar?
Is there literature about it? Maybe the Pinion is in that 3 % range already?

@JonEdwards

I happened to bump into Ben Jones from Deviate a few weeks back on my local trails and had a good look at the bike. Looks very well sorted. Barring cost (at the mo) I'd love one, and a much more interesting way to spend £5k than a blinged Santa Cruz or an HB160.

They put that much thinking into the engineering of the suspension together with the gear box - just GREAT.
Hope they succeed.

What would be great: if a professional biker starts biking the Deviate bike and starts getting into the top three of some races.
This would definitely push the product.

I reckon 3% is about the same as the difference between using draggy tyres and quick ones

I think you'll find tyres can often be bigger variation and impact than 3%.

Even on the road the difference between a fast tyre like a Conti 4000sII (~11W per tyre) and a cheaper but still fastish Michelin Lition (17W per tyre) means you're talking 12W difference between tyres, at 100W pootling output that's >10% right there, at 200W it's still over 5%.

Taking a 'slow' road tyre at over 20W per tyres means you could be giving up over 20W just in tyre choice alone, and for most people punting out 200-250W for any length of time is a hard effort, and the differences in MTB tyres can be even more extreme than the road examples too so drivetrain losses that small wouldn't be much to worry about for general use.

It's all about feel. If you 'feel' that an IHG is draggy, and it's going to annoy you

This is chicken and egg though, you adapt to what you're used to. If you spend a lot of time on fixed or SS then it's noticeably 'draggy' when you jump back on a geared bike.

If history had been different and we'd all grown up on draggy IGHs and gearboxes and then someone invented the derailleur would we find people jumping ship due to the performance increases of a free-running but niche and expensive derailleur system? For racing undoubtedly yes, but in the general sector, if it meant suddenly being saddled with increased maintenance, vulnerable mechs, custom frames and increased cost? I'm not so sure....

I have SS bikes, dedangler bikes and IGHs, I like them for different things and I am genuinely considering a Pinion machine in the future (I'd buy one right now if I had the spare £) as I'm already sold on a lot of the aspects, but you won't find me racing on one at the moment.

It's a case of what's important to you. On my commuter or on a tourer or bikepacking bike, or even a bad weather MTB, the drag and weight are a non-issue for me. But for fast road riding and racing it's still an issue, ie: it's very person/use specific as to what is an isn't an issue.

The pinion gearbox should not have the drag of IGHs as its just two meshing cogs and some shafts turning not the highly loaded epicyclics of the IGH

On the backpeddalling twospeed this is the system. Its not an IGH its a weird system with two freewheels and a ridiculous chain path

[img] [/img]
By Hirsutism - Own work, CC BY-SA 3.0,

https://en.wikipedia.org/wiki/Retro-direct

Its not an IGH its a weird system with two freewheels and a ridiculous chain path

And they're also ridiculously good fun, easy to knock up and bodge together. Use the retro/reverse gear as the overdrive/higher gear as it's a lot easier to pedal backwards cruising than it is trying to winch uphill, legs don't work right backwards!

@Tj and drag of 11s Vs 8s...

Just as another data point...there is a noticeable difference on my 11s versus my 8s hubs too when freewheeling it in the stand, but out on the trail it's not noticeably different. The mushy clutch engagement however is more noticeable on the 11s though in certain gears, 2 being the worst IME, I actually try to skip 2 on the 11s as much as possible as it [i]really [/i]annoys me!

the Pinion is already very close to the efficiency of an convential 1x11 system or similar?
Is there literature about it? Maybe the Pinion is in that 3 % range already?

I think it is close. Freshly prepared bike rolling out of the shed maybe the pinion has a little more drag, half an hour later in current muddy conditions on the South Downs maybe the derailleur has a little more drag or perhaps it's just evened things up. Overall other factors have a bigger impact, choice of tyres, pressure, etc.

Ta amedias. I guess its the better seals?

found some stuff, research about efficiency Pinion:

http://proceedings.asmedigitalcollection.asme.org/proceeding.aspx?articleid=2669549

ASME 2017 International Mechanical Engineering Congress and Exposition
Volume 12: Transportation Systems
Tampa, Florida, USA, November 3–9, 2017
Conference Sponsors: ASME
ISBN: 978-0-7918-5847-9
Copyright © 2017 by ASME

Results indicate these transmissions are comparable to many modern multispeed geared bicycle hubs, ranging from 91.6–94.95%. Single-speed and derailleur systems can obtain higher efficiencies. However, the Pinion transmission provides enhanced reliability, reduced maintenance and relocates the majority of the drive weight to the middle of the bicycle. A repeatability study was conducted on the P1.12 transmission.

Pinion reaches 95% efficiency! That is very high!

@Rubber_Buccaneer :
no wonder that you are happy with your bike!

Maybe somebody is able to find some results for convential 1x11:
remember having read something about 97%.
Possible that this number is correct? (all new, clean, shiny, lubricated)

If so:
The Pinion is maybe in the range of 2 % of such an convential drive train.

Guess much better: when you are stuck in the mud and your 1x11 isn't "clean"...

@Rubber_Buccaneer:

haha - your post was quicker:

I think it is close. Freshly prepared bike rolling out of the shed maybe the pinion has a little more drag, half an hour later in current muddy conditions on the South Downs maybe the derailleur has a little more drag or perhaps it's just evened things up

Your sensors are damned good!!!
ASME 2017 paper, above: exactly right!
😯

Deviate:

with above efficiency information plus the great Deviate suspension design...

very possible that they are able to win some races soon!

Hopefully they find an excellent professional biker.
😉

andreasrhoen - What would be great: if a professional biker starts biking the Deviate bike and starts getting into the top three of some races.
This would definitely push the product.

Its a long time since race results meant guaranteed sales.

sjshaw672 - IF there was a gearbox drivetrain that:
- Weighed less than a derailleur system
- Shifted as well as (or nearly as well as) a derailleur system

We've just had 500 internal gear bikes with drum brakes appear in Sheffield for almost free (OFO dockless bikes, look them up). I think this and time will have as much if not more effect on people taking up gearbox bikes than a lot of the stuff written above. People need to get used to bikes not having "visible" gears and then they become less the norm.

As a way of changing gear on a mountain bike my impression of the (admittedly) few rides is that they are heavy draggy and expensive. I'm not a destroyer of kit (I've never smashed a mech) so the saving in rings and chains and so on isnt something that I worry about or are particularly interested in.

I'm all for the idea of options and choice, but I'm not in a rush to buy one

I think efficiency would have to be within 0.1s of a %, and weight within 100s of g for me to really want one on a do everything bike.

I can't see me having a "gloopy weather bike" - at least not one that's not just a single speed.

An enclosed chain case would appeal to me, and might get me to consider a gearbox (as after the first couple of muddy puddles, the efficiency of the chain would still be high, negating the reduced efficiency of the gearbox), and I would be OK with that for the couple of times a year my drivetrain doesn't get covered in shite.

philjunior - I think efficiency would have to be within 0.1s of a %, and weight within 100s of g for me to really want one on a do everything bike.

Thinking about the Pinion numbers,

If they are correct so:

Wouldn't be surprised if SRAM or Shimano will try to buy them soon.
If they don't sell ... SRAM or Shimano might try to copy & start a nice mass production?

If so: Cost would come down and people would buy these kind of high technology bikes.

@thepodge:

Its a long time since race results meant guaranteed sales.

Some interesting posts above - good discussion chaps!

I like the idea of a gear box - less maintenance, less prone to damage etc.

They seem fairly efficient at the moment looking at the data provided in the posts above.

I think what it needs is a manufacturer to jump on board with it and be able to get the prices lower. At the moment it looks to be around £6k for a carbon full susser.

Didn't I see a post a while back that Sick were producing a gear box frame? Anyone have details on that?

thepodge - Member
philjunior - I think efficiency would have to be within 0.1s of a %, and weight within 100s of g for me to really want one on a do everything bike.

Of what though? XTR or Alivio?

Out of the box they're probably identical, infact apart from the mech going a bit sloppy I bet they're the same for the life of the parts.

The pinion is 95% efficient, a derailleur is 99% (+/- 1% depending on chain lube, jockey wheels etc).

If a hypothetical system carried no weight penalty, was as efficient, etc, then why not. But nothing comes close to a derailleur (yet).

What wattage was the pinion efficiency test 95 ? For example a rohloff is 96% on paper if your putting out a constant 200w. Drops to 92 at 50w though.

Derailleur systems between 93-98% depending on gear and power used for test.

has anyone mentioned the url for this thread yet?

[url= http://singletrackworld.com/forum/topic/gearbox-fanshaters-what-if ]http://singletrackworld.com/forum/topic/gearbox-fanshaters-what-if[/url]

unfortunate '/' removal.

as you were.

dirkpitt74 - I think what it needs is a manufacturer to jump on board with it and be able to get the prices lower. At the moment it looks to be around £6k for a carbon full susser.

That's not just down to the gearbox though, carbon tax, aspiration tax, niche tax, low volume tax, they all add up.

If someone wanted then they could realistically get an alu frame full suspension gearbox frame at a competitive price. I think Sick could be the ones to do that.

trail_rat - Member

What wattage was the pinion efficiency test 95 ? For example a rohloff is 96% on paper if your putting out a constant 200w. Drops to 92 at 50w though.

Thats interesting - presumably part of why we don't feel the drag so much on the tandem

Ref: Wattage of tests, the only tests I've seen were the ones that produced this graph:

[img] [/img]

Which shows output for both 50W and 200W for various drive options.
Efficiency doesn't just vary by input power, but by the specific gear too, this affects epicyclic IGH's and Alfines specifically worse than the Pinion.

While the 'Hoff is spiky, it's actually over a small range so pretty small actual variations between gears. The Pinion is reasonably flat too, the 8s Alfine especially though is massively variable!

Basically, if you're spinning around in 4th* on an A8 at lower power you're gonna feel it! the worst gears on the A11 are at the end where you're more likely to be putting out more power so although they are 'worse' they're not as bad in reality.

*It's an annoying quirk of the 8s really that right in the middle or the normal 'pootling' range is the least efficient gear. It really is worth while paying proper attention to your ratios to make sure you spend the bulk of your time in the right gear.

Imagine the difference in perception between two riders, one who spends 90% of his city commute in 4th, and one who spends it in 5th. a few teeth on the chainring could totally alter your perception of the hub.

** Also worth noting I think the Inter8 on that graph is actually a Nexus, not an Alfine, same gearing but plain bushes not bearings on various bits so an A8 will be marginally better than the N8 on that graph.

Has someone intergated a gearbox with an electric motor yet?

That would be awesome on an ebike

Has someone intergated a gearbox with an electric motor yet?

Alfine Di2 + Electric assist has been done a lot, we have it (at Bike Charity) on a Larry V Harry cargo bike, auto shifting + e-Assist, just pedal and go, it's ace! It even auto shifts back to a predefined 'starting' gear when you stop.

Just been looking at the Pinion site - not worked it out properly but the all-in numbers (inc steel frame hardware etc) look a bit heavy at the moment (crank arms look a bit of a lump compared to HT2). Suppose there are some small savings to be salvaged with a light rear hub etc.

We had a day biking in Copenhagen last year (belt drive Biomega with Alfine). In an urban setting I really ended up driving it like a car - shift to low gear at the lights, then set off sat down and quickly shifting up through gears.

@amedias:

great information!

Most surprising: Speedhub - Rohloff

mtb & Speedhub: are there still brands offering the speedhub on an mtb? I guess not. Too much weight for the rear hub / suspension problems?

but for those where this weight issue is no problem: looks like the Rohloff is as efficient as an conventional drive train. (Without having the maintenance hassle.)

Pinion: they put the additional mass into the correct location.
neat.

I keep threatening to start a dedicated thread or a blog about this but still not got round to it. Seems to align with a few discussions on this thread though.
Interesting to hear the 'mushy clutch' comments on the Alfine. I wonder if that's the actual cause of the flexy feeling when I try to wheelie or sprint - I'd assumed it was twist in the frame - it's probably a combination of both.

Anyway, enough ponderings. Want a low CoM, low unsprung mass, "gearbox bike"? Build one yourself. I give you [i]Alfino Bombino[/i]:

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