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- This topic has 108 replies, 31 voices, and was last updated 12 years ago by thepodge.
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18 speed MTB gearboxes
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PJM1974Free MemberPosted 12 years agoIt looks like the concept has some considerable way to go before it’s accepted in the marketplace – by that I mean that I’d consider buying a gearbox bike.
For starters, a case full of sturdy intermeshing gearwheels and bevels doesn’t exactly scream “lightweight and efficient” at me, anecdotal experience of the Hammerschmidt system tells me that even relatively small frictional losses through planetary gears will be noticable.
Secondly, if it doesn’t take off you’re left with a bespoke frame requiring a bespoke transmission and bespoke seals which would raise doubts about potential lifespan due to lack of spare parts.
Thirdly, someone has raised a point about a CVT style gearbox being the way forward. I rather like the idea of that…
jesFree MemberPosted 12 years agoBadly expressed point by me. I don’t get the ‘I’d never have a bike with any form of “Gripshift” even if there were numerous other advantages’ thing.
The Rohloff shifter has a slightly different feel to “Gripshift” and makes sense when you use it, unfortunately very few people get the opportunity to try it out for themselves, due to cost and niche nature of Rohloffs.
I would liken it to flappy gear changer on high end sports cars, they may be awsome but barring a lottery win, stepping into the Clarksons shoes for a day, or having a wealthy budy with a suitable car he can loan me I will never know 🙂Talking of trying things out anybody know if there will be a Helius AM Pinion to demo in the UK over the next couple of months.
Reminds me of the person who told me they could never ride a Rohloff as you can’t get floating disc roters for them….
You can get a Hope V2 floating rotor now 🙂
V2 Rohloff floating rotor[/url][
cookeaaFull MemberPosted 12 years agobikes evolve, fat bars, seat posts, 7,8,9,10,11 gears
mostly retro-fittable bits of kit for existing bikes at their time of release then… Thanks for reinforcing my point for me… 😉
I’ll agree that frames built around a gearbox is probably where we’re headed ultimately, but you don’t persuarde the majority consumers to bin their current perfectly good bike for a new expensive whirlygig overnight, you need a ‘Gateway’ product that shows the benefits in an affordable package, and that is very achievable in this instance…
thepodgeFree MemberPosted 12 years agoCookeaa, as I’ll not be able to afford the legal fees in any way, shape or form to protect them, they will be in effect open source… Once I’ve finalised them
TandemJeremyFree MemberPosted 12 years agoThe trouble with building a gearbox that will fit any frame is that it will always be compromised.
I really like the look of this concept. Twistshift don’t worry me, 18 gears sounds a good number – its a greater gear range than 3×9 but with small and even gaps. Efficiency is the real bugbear – if they can get that right it will be a help
thepodgeFree MemberPosted 12 years agoPMJ, it would be expensive but I bet you could get a standard bb & attachment machined up to replace a gearbox should it ever stop being produced.
thepodgeFree MemberPosted 12 years agoTJ, is that more or less than the compromise we live with now due to existing product designs?
Ps, I’ll sort those shifters when I get home
TandemJeremyFree MemberPosted 12 years agocompromise with current gearbox designs – they either live in the rear hub with weight distribution and shifting issues or in the frame with 2 chains
cookeaaFull MemberPosted 12 years ago@cookea – you’ve basically described Alfine, there.
maybe its one possible solution to the whole problem which has it’s own +/-ives… there are others
The trouble with building a gearbox that will fit any frame is that it will always be compromised
All bikes have compromises of some sort, the real trick is making the set of compromises one that people can live with and would pay for over another given set of compromises…
that pinion ain’t perfect and requires some compromises in service, like shifting under load, weight and possibly gear box efficiency? better than another AM bike with a 2×10 XT drivetrain? maybe…
thisisnotaspoonFree MemberPosted 12 years agoThe trouble with building a gearbox that will fit any frame is that it will always be compromised.
This, except replace ‘comprimised’ with ‘****’.
Where would you put it? Under the BB, fine as long as everyone rides arround on steel hardtails with identical downtube diameters so it has something to clamp to.
And how many riders of hardtails (so frames costing £100-£400) are going to want to spend £2k on gears (and you still need cranks) when SLX is only £250.
The people with money to spend will spec them on new bikes, the people who dont will use mechs and cassetts like normal. It might trickle down to an XTR pricepoint, and become fairly widespread, but I can’t see it dropping much below that, look at the cost of an alfine 11 Vs XTR, and alfine is definately the Deore to rohloff’s XT.
All bikes have compromises of some sort, the real trick is making the set of compromises one that people can live with and would pay for over another given set of compromises…
Sums it up, the advantages of a gearbox are
*centralised mass
*ground clearance (no mech, and possibility to run tiny chainrings)
*low maintenanceTry and retrofit that to an existing bike and you end up with less ground clerance as it would probably need to sit under the BB somehow. And you’d add a lot of weight as the box would still need 2 shafts but now you’ve got a third (the cranksaft) and primary drive chain adding weight and maintenance.
thepodgeFree MemberPosted 12 years agoTINAS, the people who like ihg will go for it and clamps can come in any size & shape.
Plus current ihg don’t cost 2k so why should any other retrofit gearbox?
thepodgeFree MemberPosted 12 years agoYou’d probably have less chain links on a twin system than a standard setup, ergo, less chance of failure when you consider no side to side loads
simons_nicolai-ukFree MemberPosted 12 years agoYou can get a Hope V2 floating rotor now
V2 Rohloff floating rotor[I don’t like their prices much. Basic Hope/Rohloff disc £61! Wiggle list those at £26rrp.
Floating vented rotor £91!
simons_nicolai-ukFree MemberPosted 12 years agoPeople get too hung up on the retro fit thing
I’d go for different examples but the argument is sound –
– suspension forks. Longer travel suspension forks.
– rear suspension (the Thudbuster was the ‘compromise’)
– Disc brakes
– 29ersEven on a Nicolai build the frame is usually less than half the total build cost. On a mass market bikes it’s probably less than 10%.
Efficiency is the real bugbear
Is there any reason it should be large problem? On ‘adapted’ designs like the G-Boxx 1 you have secondary drives and things but this should be far more transparent. Claimed 95% but I can’t find the source at the moment.
thisisnotaspoonFree MemberPosted 12 years agoTINAS, the people who like ihg will go for it clamps
Why would they (mass centralisation would be the only benifit), and most rohloff users tend to buy into it for it’s low maintnance. I can see gearboxes taking that market, but only as a neater solution with advantages.
can come in any size & shape
Yes, but the gearbox is going to need to be mounted pretty rigidly to the frame, which means close fitting, which means following the shape of the frame.
If it hund down under the BB (and therefore below the level of the Bash guard, how long untill someone bottoms one out on a rock and writes it off?
Plus current ihg don’t cost 2k so why should any other retrofit gearbox?
Becasue the pinion one does?
A 10 speed hammerschmit would be great as a retro fit option, but isn’t available (or in my mind even possible to package). And anything below the BB is comprimised in terms of packageing and protection, and anything above the BB is limited to hardtails or a very small number of FS designs. And both designs would need a primary drivetrain from cranks to gearbox, a secondary drive back to a gear running cocentric with the cranks, and a tertiary drive to the rear wheel (otherwise it’s going to clash with the chainstays), hardly maintenance free? and even if you develop all that, you’ve got just a few years to make your money back as the people looking to spend that level of moeny are probably the type to buy a new frame every 2-3 years.
I think this ideas going to be either a ‘standard’ mounting, or bespoke gearbox/frame packages (no reason the internals couldn’t be licenced and put inside different frames though).
Edit: this makes my point much more clearly.
rear suspension (the Thudbuster was the ‘compromise’)
Rohloff is the ‘compromise’ (or a hammerschmidt dinglespeed).
thepodgeFree MemberPosted 12 years agoI took 2k from your example.
I’m thinking of ways to make it work, you’re thinking of ways it won’t.
I can put equal counter arguments to all your points but I’m at work so I’ll do it when I get home instead of on my phone
jesFree MemberPosted 12 years agoI don’t like their prices much. Basic Hope/Rohloff disc £61! Wiggle list those at £26rrp.
Floating vented rotor £91!
😀 The floating vented rotors are exspensive (even 6 bolt versions) which is why I live with the standard version.
The company is pricy but I guess thats down to be being one of the few that stock parts and spares for a range of IGH.Any thoughts on demo’s for the Helius AM Pinion ? 🙂
TandemJeremyFree MemberPosted 12 years agoEfficiency – I hope they can get it down to similar to conventional gears but its tricky. the pinion gearbox at lest is not planetary gears son stands a chance but gear trains always absorb some energy
messiahFree MemberPosted 12 years agogear trains always absorb some energy
That’s my experience of Alfine and Rholoff… going back to normal drivetrains on lighter bikes was a revelation 😆
TandemJeremyFree MemberPosted 12 years agoPlanetary gears as in rolf and alf are worse than conventioal gearboxes as in pinion design tho
cookeaaFull MemberPosted 12 years agoTINAS – Eh? what?
Gearbox under the BB?
New set of cranks?
10spd Hammerschmidt?Where’d you get all of that from?
I would propose a basic spec based around providing a retro-fittable gearbox that could live somewhere inside the nominal free space of the front trinagle of say a 14″ or larger, 68/73mm wide Euro BB, hardtail frame, and would be mounted to the BB shell and/or seat tube clamp(s) (Sorry no space for bottle cages now, first compromise is that you buy a camelbak, die of thirst or drink from puddles).
The drivetrain would be a 3 stage affair based around the following loose requirements:
the Gearbox will accept input (by chain, belt or pinion gearing from a ‘standard’ set of cranks (104/64 PCD HT2 or similar, 5 arm compact if you wanted perhaps).
The gearbox (would by whatever means the designer(s) chose) provide a gearing range at least equivalent to that of a 1xN 11-36 cassette with a 32t chainring and ideally greater (again in whatever increments and whatever number of gears the designer felt appropriate/practicable.
The Gearbox would output drive to the rear wheel by chain or belt drive (whichever the designer(s) felt most appropriate).
Gear change shall be affected by use of a handlebar or frame mounted shifter, which may be of any configuration the Designer(s) choose (Twist, trigger, thumbshifter – indexed or friction)…
There’s a starting point anyone who can’t dream something up to meet that must be completely devoid of any mechanical imagination…
The Compromises with it would be obvious no doubt, COG may be more central but wouldn’t be low, there would be limited frame compatibility of course but you can design it to work with the largest practicable range of frames and current standards, you would be limiting your market to hardtails, but seeing as the majority of bikes are Hardtails that’s probably not as much of a limit as inventing a new bespoke geabox mounting standard (again)…
I’m thinking of ways to make it work, you’re thinking of ways it won’t.
+1
It’s quite easy to pick holes in most things, quite another to think your way around them…
simons_nicolai-ukFree MemberPosted 12 years agoHelius AM Pinion demo
Not any time soon – supply of gearboxes has been delayed so it’s looking like first bikes with customers in August/September. We’ve been prioritising customer bikes rather than getting one as a demo for the moment but will be looking at getting one in (although if it’s for me it will be in XL).
kimbersFull MemberPosted 12 years agoim just quietly hoping that somewhere in the recesses of shimano R&D that a team is battling away at designing a gearbox that will fit inside an extra large BB – 12 speed would be plenty imho
they are the only people that could realistically make it happen and have the industry design bike around it
guess ill have to wait a few more years then
jesFree MemberPosted 12 years agoOk that’s a shame, and XL is a fail as I believe I need a medium.
Don’t normally demo bikes but I think in this case I would like to just to see if sizing and function match expectations/cost ratios. 🙂Thnaks you for the feedback.
simons_nicolai-ukFree MemberPosted 12 years agoJes – Moonglu in Ripon are planning on running a Large demo (and they’re in the first delivery) which would let you judge function.
Sizing will be the same as the regular frame design (Pinion is now an option on all Argon and Helius frames) so won’t be a problem for you to ensure you get the correct size.
NicknoxxFree MemberPosted 12 years agoI’d go for different examples but the argument is sound –
– suspension forks. Longer travel suspension forks.
– rear suspension (the Thudbuster was the ‘compromise’)
– Disc brakes
– 29ersYes, my examples were rubbish, I was in a hurry, but frames do evolve all the same. As well as your examples there’s ISCG, Funny headset sizes, new materials. . .
People who are likely, and able, to buy a Pinion compatible frame aren’t going to be too bothered about buying a new frame. As I said, it’s the cost that’s the crucial factor.
jesFree MemberPosted 12 years agoMoonglu in Ripon are planning on running a Large demo (and they’re in the first delivery) which would let you judge function.
Thanks again, I will keep an eye out for dates.
thepodgeFree MemberPosted 12 years agoCookeaa, your reply is almost exactly what I was going to.
Kimbers, limiting something to fit a standard that it was never designed for is the first rule to making things fail. they should not be designing something to fit in an extra large BB. Sram have the I-motion 9 and the Hammerschmidt under their belt so I would have thought they’d be first out of the blocks, not Shimano.
Simon / Nicknoxx, all of those examples (except the 29er & rear suspension) can all be fitted and removed without any bother, you dont need anything built in into the frame from the start (discs are a slight grey area) and if you didn’t like them you can revert back to what you used to use with no bother so I don’t really see what you’re getting at.
ratherbeintobagoFull MemberPosted 12 years agoPinion is now an option on all Argon and Helius frames
Including the hardtails?
Andy
compositeproFree MemberPosted 12 years agolimiting something to fit a standard that it was never designed for is the first rule to making things fail.
Gets it!!!
thisisnotaspoonFree MemberPosted 12 years agoThe Compromises with it would be obvious no doubt, COG may be more central but wouldn’t be low, there would be limited frame compatibility of course but you can design it to work with the largest practicable range of frames and current standards, you would be limiting your market to hardtails, but seeing as the majority of bikes are Hardtails that’s probably not as much of a limit as inventing a new bespoke geabox mounting standard (again)…
Exactly, so the ‘comprimises’ in getting an after market universally compatible gearbox to work rule out pretty much all of the advantages with the exception of no mech, (but you have added 2 maybe 3 chains).
And the point about the majority riding hardtails defeats itself.
Firstly the majority won’t buy it, they can’t afford to, however good it is only a handfull of people can buy a £2000 drivetrain.
And what proportion of hardtail riders do so for any of the following reasons:
a) efficiency
b) lightness
c) cheepness
d) nichenessa and b won’t buy a gearbox regardless of what format it’s in, that last 5% efficiency matters too much in an XC race.
c won’t buy it
d will buy it, but would probably buy a niche frame with a gearbox mounted properly.Think if it this way, I could buy a on-one hardtail for £150
I could buy a hardtail with a geabox (if on-one made one) for ~£2000
Or I could buy a gearbox that would cost at best the same, or more likely a lot more as it’s going to need all kinds of fixings and bodge it into my current frame and weigh more.
I think the intended market is far more likely to swallow buying £3000 full susser frames (which already exist, and you’re effectively getting a free drivetrain with that) than £2000 add ons which don’t offer all the advantages. Especially when they can get a rohloff already.
Edit: how much is this gearbox? pinkbike seem to think it’s a 2000euro add on, the nicolai site puts it s smidge over 1000euro (which makes it a bargain IMO).
simons_nicolai-ukFree MemberPosted 12 years agoPrice is looking like a c£1400 upcharge on top of the frame cost.
paulrockliffeFree MemberPosted 12 years agoYour a,b,c,d list is missing the most important factor; e) Fit and forget.
That would be the most important thing for me. I’d happily trade a little inefficiency for knowing my bike is going to work exactly the same for a long time without having to worry about indexing gears, stretching cables, rings wearing, chains wearing etc etc.
Without riding one, I expect that you’ll find that it’s 5% less efficient than a chain setup (for example) but that 5% is only 20% of the drivetrain losses, the other 80% being the interface between tyre and ground.
The box design looks fairly easy for anyone to design a bike around, it just bolts to the bottom of the bike. I wonder if there’s any mileage in Pinion making custom cases that are structural for disipating shock loads for designs like the Trek Fuel. That could allow slightly lighter tubes.
Looks very interesting and I’d love one of those Nicolai’s!
thepodgeFree MemberPosted 12 years agogears are a compromise over singlespeed regarding maintenance but people put up with it, suspension forks are a compromise over rigids regarding maintenance but people put up with it. why wouldn’t they put up with supposedly more maintenance (though I disagree there would be any) for the benefits of a retrofit gearbox? The design concept I have uses just one more bearing and although I’ve not measured it, I’m estimating pretty much the same overall chain length as a derailleur set-up. hardly more maintenance.
there are loads more categories of cyclist than a b c & d that you mention above.
paulrockliffeFree MemberPosted 12 years agoI was saying there would be less maintenance, which is a massive plus for me. Sorry, I was talking at cross-purposes as I didn’t realise you’d moved on to a retrofit kit rather than the Pinion one.
Anyway, on your idea, obviously without seeing it it’s hard to comment, but I’d imagine I’m the sort of person that would be most amenable to the right idea.
The thing is I can’t see a pressing need for it so I’d be in no rush to upgrade despite how much I like the idea. I can’t see I’d bother upgrading an existing frame when I can wait until the next time I buy a new frame and have it all properly integrated.
simons_nicolai-ukFree MemberPosted 12 years agoe) Fit and forget.
That would be the most important thing for me. I’d happily trade a little inefficiency for knowing my bike is going to work exactly the same for a long time without having to worry about indexing gears, stretching cables, rings wearing, chains wearing etc etc.
That’s pretty much my experience of Rohloff. I know there are a few people who’ve had trouble but for most of us it’s maintenance free for over a year at a time. Sprocket/chain/chainring do wear but not in the problematic way they do on a conventional system and those parts will still wear on the Pinion.
MidlandTrailquestsGrahamFree MemberPosted 12 years agoPinion is now an option on all Argon and Helius frames
This thread suddenly got a lot more interesting. 😀
There’s been no mention of a pinion gearbox combined with a belt drive yet, unless I’ve missed it. Would that be an option on the Argon 29er ?
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