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There is no magic solution to that, it’s fundamental to how gearboxes work.
depends on how the gearbox works. If you're using a gearbox like a car one (I don't know the technical term) then you're right - if its just a mech and chain in a box (as the honda system, and the shimano patent) then you can still have the cost/friction benefits of a mech system, but without things dangling off the back of the bike
for me, Rapid Rise mechs worked really well with gripshift. you could shift into easier gears whilst rotating your hand to grab the brakes, it was a subtle move, but worked well compared to the push thumb whilst extending forefinger operation of normal trigger shofter and normal mechs.
I think I could use a 10 or 11 speed gripshift (x-actuation) old 9 speed mech and a j-tek shiftmate to get that to work on my 10 speed setup..
I loved that combo as well lovewookie… rapid rise + Sachs wavy shifter.
Pace did this too in ooh, 2004?
Yup, I owned an RC-40 for a while. The travel adjust was a PITA, sometimes you’d be riding along a perfectly flat surface and would hit a small pebble, there would be a “zzzp!” noise from the right leg and 30mm of travel would magically disappear.
I had some RC40's too and loved them. From memory it was the other way round, you turned the lever to lock it down but if you hit something they'd go back to full travel? Could be getting them mixed up with the Pace based DT Swiss I had later though? Thinking about it, mine were 2006ish so they'd maybe fixed it by then? Either way, they were ace.
Yup, I owned an RC-40 for a while. The travel adjust was a PITA
I'm not talking about travel adjust, I mean the lock-down feature that you describe in your second paragraph. It was useless for locking out on the road, as I hated riding with the bars 30mm lower, but it was quite nice on silly steep climbs.
Upside down forks.
We've just had some well used SIDs and an RS1 serviced. Forks mainly die due to dirt and water ingress. The RS1s were like new inside as water just can't get in unless you store them upside down, and the bushes are permanently bathed in lube oil. The SIDs scraped through service but are on their last legs. We've been paranoid about not bashing the stanchions on the RS1 (would prefer if they had a bashguard kit) but otherwise they've been ridden in the same conditions.
if its just a mech and chain in a box (as the honda system, and the shimano patent) then you can still have the cost/friction benefits of a mech system, but without things dangling off the back of the bike
Good point about the friction benefits, but that depends on whether it can be made reliable enough - a snapped chain in a gearbox is a whole different thing than in a traditional derailleur system.
A derailleur-in-a-box will always be more expensive than a traditional system because there are more parts to manufacture. You need a casing that has to be mounted in the frame and sealed against dirt and water. The frame will have to be designed around the packaging limitations of the transmission, which may add expense, especially for suspension bikes. There will be packaging limitations because you need a certain amount of chain slack to be able to shift gears, so there will be a limit to how close the two cassettes could be, plus you need to fit in a chain tensioner.
Plus the derailleur and shifting mechanism will probably need to be more precisely manufactured. Instead of one cassette, you need two, otherwise you'd need an insane amount of chain slack. You need at least two shafts and two sets of bearings, and you may need two derailleurs or some sort of complex derailleur that alternately moves the tensioned and slack sections of chain (i.e. you're basically alternating between shifting front and rear gears on a traditional derailleur system). It might be cheaper than a traditional gear set, but that's assuming that it can be made reliable enough for mass-production.
The grease ports WTB used to have on some of their hubs. In fact, it'd be amazing if all bearings on a mtb had grease ports or similar.
There was a compression blow off valve on the right leg that allowed you to slap a dial on the right leg and lock the fork in a reduced travel mode until the fork encountered a bump and you’d ping back to full travel again.
I don't think anyone has mentioned Terralogic. It sounded like a great idea, apparently the reality was that you hit a bump, lost your fillings, and only then did the fork release?
Wasn't that adjustable? It's what Specialized have on their XC bikes isn't it?
Electronically controlled suspension damping should be a mainstream thing by now.
K2 / Proflex were messing with this in the late 90s. Yes it was a bit rubbish but everything was a bit rubbish back then.
mick_r
....water just can’t get in unless you store them upside down, and the bushes are permanently bathed in lube oil.
Yeah, they just make sense. Weird that nobody has made it work for mass market, you hear the stiffness argument but the Lefty seems to manage with half a fork
Geomatron, remember them? Adjustable on the fly geo.... Not sure what happened to them. Never owned one.
The main difference and why motorbikes have upside down forks is that you have the biggest tubes at the head tube area, with triple clamps so maximising stiffness. Plus you can have a massive bolt through axle without worrying about ease of removal etc.
And weight isn't as much of an issue on a motorbike that weighs 180kg.
I don't think gearboxes will ever hit mass market, they're too expensive to make and require a proprietary mount so the bike has to be designed specifically for them. On the shifting under load subject, it's not that you can't shift under load, it's that your hand can't generate the require force to shift under load - a future electronic system with a strong servo/motor might get around this.
I’m not talking about travel adjust, I mean the lock-down feature that you describe in your second paragraph. It was useless for locking out on the road, as I hated riding with the bars 30mm lower, but it was quite nice on silly steep climbs.
That's how it's meant to work, but the right leg travel adjust on my RC-40s regularly failed and I ended up having to return them to Pace several times. Mine never quite worked properly.
I had some RC40’s too and loved them. From memory it was the other way round, you turned the lever to lock it down but if you hit something they’d go back to full travel? Could be getting them mixed up with the Pace based DT Swiss I had later though?
No, you're absolutely right - I was referring to the build quality of my own RC-40 forks which was patchy at best. When they worked, they were lovely forks but all too often they didn't.
Geomatron, remember them? Adjustable on the fly geo…. Not sure what happened to them. Never owned one.
Bionicon, wasn't it?
why’s that? 29ers (similar gap to a 26″ wheel) are percieved by many to be better overall these days – 32ers are coming (trek are playing with them I think), its just a matter of time. They would definitely have some disadvantages, especially on smaller frames, I’m curious why large BB drop is one of them though?
You can't just keep adding. More must be better, not always.
Greater BB drop = harder to lift front end. Add the additional wheel size and the bike is going to be much harder to manipulate (more leverage harder to move weight over pivot). MTBs are already quite hard to get the front up as seen by everyone having to push down to pull back and up. 32" wheels would be very hard work for all but the tallest.
ta11pau1
Full MemberThe main difference and why motorbikes have upside down forks is that you have the biggest tubes at the head tube area, with triple clamps so maximising stiffness. Plus you can have a massive bolt through axle without worrying about ease of removal etc.
All motorbikes have triple clamps regardless of fork design though, and the bolt through axles work the same way whether up or down, and are pretty comparable. Big tubes are good for fore/aft stiffness but losing the fork brace is bad for twist
That’s how it’s meant to work, but the right leg travel adjust on my RC-40s regularly failed and I ended up having to return them to Pace several times. Mine never quite worked properly.
Ah, so you were riding along with them locked down?
Weirdo!
you hear the stiffness argument but the Lefty seems to manage with half a fork
Ah, Leftys. I think the most interesting think about them is that they use square slider tubes needle roller bearings, and rely on a boot for a top seal, in the name of friction reduction. And it works too. I think the single-sided bit came about because this solution is heavy, but has the side-effect that it can't twist like cylindrical bushings can. So you can get away with one leg to eliminate the weight penalty.
Wondered when a lefty fork would come up and as an owner of one I was going to suggest it myself. The thread title could pretty much apply to Cannondale anyway. The lefty though, great when working properly, massive pain when it isn't and usually hugely expensive to rectify.
Leftys do work pretty well, and no doubt if they were mainstream with the same sort of budget as other forks would be better still. They just look weird, is all.
Unless on a fatbike, where they look awesome.
Wasn’t that adjustable? It’s what Specialized have on their XC bikes isn’t it?
TerraLogic was just a basic lockout with a blow-off / bypass valve.
Before suspension design and tech had learnt how to overcome wallowing and sagging, you had to put a lockout on it to be more efficient but then riders would forget to unlock it and set off on a descent with the fork or shock still locked out which usually broke it.
TerraLogic wasn't necessarily an improvement in suspension tech, it was a way of trying to make the thing more idiot-proof!
Specialized refined the concept with the Brain rear shock which (after a couple of iterations) was very good indeed.
I’m nt sure 1.5″ steerers are lighter, given the need for a much larger had tube on the frame, a bigger stem, etc Tapered is strong where it needs to be – at the join to the crown.
1.5in was better, looked FAT and was also much cheaper in terms of machining especially on aluminium frames. This and the prohibitive cost of retooling for smaller frame manufacturers has lead directly to the straight 40mm headtube with silly external bearing on the bottom bodge.
@honeybadgerx I have a WTB Momentum headset on my folder (itself a long bankrupt Mezzo) with grease ports on both races. Works a treat even after 15 years.
Before suspension design and tech had learnt how to overcome wallowing and sagging, you had to put a lockout on it to be more efficient but then riders would forget to unlock it and set off on a descent with the fork or shock still locked out
That's an experience everyone should have at least once.
good ol' Cannondale with the ideas 🙂
Is my memory faulty, or didn't they do a rear suspended road bike way back when?
Do you mean Bionicon bikes?
By the time I was on suspension bikes, decent forks and shocks had blowoffs anyway. (my Revs made a funny noise if you rode them too hard while locked out).
This is another "bike technology that did work, and does work, and has gone away a bit, but should and probably will come back" though- propedal. I hate this current idea that you just throw antisquat at everything and suddenly all bikes can climb and descend perfectly on a single shock setting. Never ridden a bike yet where it's remotely true (the closest I've found is Trek, but that's because they basically have 2 shock settings in one- the antisquat and the clever shock work in hand. But it still benefits from propedal).
I'm not saying that it's not a valid way to build a bike- I had a BMC Trailfox 29, which was genuinely brilliant- fantastic shape, best geometry I'd ridden at the time, it's one of those bikes that you can look at new bikes today and see much the same numbers. But I hated, absolutely hated the suspension. Bottom line was, it didn't know whether the lump you're pedalling at was a rocky climb, or a fort william downhill rock garden, and it reacted the same to both.
The race team loved it- and to bbe fair, most times for me, it was fast. Just, fast and horrible feeling.
Meanwhile, the propedal also can't tell if you're on a climb or a rocky downhill, but it has a lever. There's other tricks like brain shocks, sensor controlled shocks etc but all their development has done is made them react faster and faster- which no matter how fast you get, can never beat foresight.
Today's awesome bikes with today's awesome materials and designers AND a propedal switch, that's an awesome combo.
1.5 steerers, (imagine the One Up EDC on that).
Upside down forks, we’ve been sold on the ‘stiffness = better’ marketing but whenever I’ve ridden Dorados they’ve been as good as any thing else out (and much older) and my only SC Shivers might have been been a bit flexy but they rode as well as anything else in the market.
Gearbox will get there one day.
20mm front axles
Grease ports
Sensible standards that last more than 10 minutes.
Sensible standards that last more than 10 minutes.
Ha! Good one. 😀
Is my memory faulty, or didn’t they do a rear suspended road bike way back when?
I can remember there was a Bad Boy version of the Jekyll in the early 2000s
All of that can be addressed through engineering design and development…
Rohloff have been developing their gearboxes for what? 20 years now? And Shimano have been doing gearboxes for years and years as well, and don't rate theirs for off-road at all. If they thought that 1. there was a market for them, and 2. they could make them cheap and reliable, they would've done so already, no?
I like the Honda cassette and derailleur in a box though, that is a good idea. Comes with many many issues of it's own though.
I don’t think gearboxes will ever hit mass market,
Hub gears are the norm most of europe on anything but entry level bikes - but then that market is utility led not fashion
but then that market is utility led not fashion
Oh shut up.
Hub gears are the norm most of europe on anything but entry level bikes – but then that market is utility led not fashion
Difference being that you can buy a shimano hub gear for £100, that requires only sliding dropouts, nothing more. That same bike will also fit regular derailleur gears.
A pinion gearbox is close to £1000, and a frame that will fit one cannot fit regular gears with a normal bottom bracket chainset.
For the MTB market that's not an issue, but getting costs down to a few hundred quid will be extremely difficult. I have no issue with this.
I did a cost comparison using a Ti frame and an XT groupset vs a Pinion gearbox with belt drive, the pinion works out at around £900 more. If you're building a several thousand pound bike, it's not so hard to accept that cost.
As someone else said, if there was a market for mass produced gearbox drivetrains, you can bet either Shimano or SRAM would have developed one by now. I for one like that MTB has the 'cutting edge' area of development.
@crazy-legs @molgrips I thought Terralogic was the one with (IIRC) some sort of brass weight that acted as an automatic lockout, rather than just a blow-off?
I-Beam saddles. Never tried one but it always looked like a promising idea.
I guess having to change both seatpost and saddle put a lot off and it never really established itself as a standard.
Surely an i-beam saddle would not have any 'give' in it which would make it pretty harsh?
Surely an i-beam saddle would not have any ‘give’ in it which would make it pretty harsh?
Definitely. I'd forgotten all about it but this reminded me. When I got my singlespeed (an eBay bargain) it had an iBeam saddle on it. I'm used to riding lightweight saddles with very little padding but that thing was like it was made of concrete. Easily the least comfortable saddle I've ever ridden on.
I think someone up there mentioned bionicon bikes. I rode one at a demo day at Laggan once and loved it, but don't think I'd ever want to own one. Can't even begin to fathom how to fix all that hydraulic stuff if it went wrong.
Had a couple of I-beams. Passable on the DH bike, but not sprung like a traditional saddle as mentioned above. Also, the post never gripped the saddle as well as a normal 2-bolt setup anyway so it could end up pointing up/down. One of them did have a ratchet sort of setup, but then you lost the ability to adjust it exactly as you wanted.
The clamping bolt was always slipping on the 2 or 3 Ibeam posts I had, annoying at best...
ooh I'd like to add the 8pins seatpost. how every dropper should be made..
https://www.eightpins.at/en/technology-en/
Hub gears are the norm most of europe on anything but entry level bikes
Like bikes 40 years ago in the UK that mostly had Sturmey Archer 3 speeds, they may have been, but they're not now. Most bikes in Europe (like most bikes in the UK) have derailleurs, because; cheapness.
Not once you get above entry level. Most have hub gears. Just check it out in the low countries and germany. entry lever - derailleur, mid range - nexus and sram 3 - 8 speeds. top of range - rohloffs
https://www.gazellebikes.com/en-gb