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How are we feeling about gearbox Dh bikes now ?

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I know with the recent influx of gearbox bikes from Atherton, Gamux, Intense and Zerode that anyone in DH circles was massively interested to see how it went and whether it'd influence the market in the coming years for players like Trek, Specialized, Santa Cruz etc.

The reality is though, gearboxes haven't set the world alight in WCs yet. There's the winner from junior male last weekend of course on the MS Zerode, but apart from that, we've not seen them at the pointy end.

So, what's the thoughts from the masses on here ?

 
Posted : 10/06/2025 11:39 am
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XC is all about weight and efficiency and Gearboxes aren't there yet, but in DH where centralised mass down low helps with stability I can see it growing and becoming normal.

Please less maintenance, as my dad is rubbish at it 😉  

 
Posted : 10/06/2025 11:49 am
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I feel the sudden surge in weights being added to non-gearbox frames is partly driven by gearbox bikes turning up and doing pretty well (and the riders talking to each other, and riding eebs obvs).

And I reckon if Loic or Jackson were on an Intense or Atherton, they'd still have won.

 

 
Posted : 10/06/2025 11:59 am
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If I was buying a DH bike now it would 100% have a belt and gearbox. Just because. 

I'm never going to race in my life so it doesn't matter to me what the world's fastest riders can or can't do on them. If Jackson Goldstone was riding a Zerode it would be a different story.

 
Posted : 10/06/2025 12:01 pm
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Given Jackson Goldstone had 1.3kg of lead strapped to his downhill bike, there certainly isn't a weight penalty from them.

I'm curious if the centalised mass around the bottom bracket is to get them feeling like their ebikes so it's easier to swap between bikes or a genuine advantage to handling.

 
Posted : 10/06/2025 12:03 pm
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I think it won’t change much for the foreseeable future because the big teams are tide to sram / Shimano so won’t change until they make one. The question I guess is has a gearbox bike not won yet because in many cases those more likely to win are not on bikes with them. I can see gearboxes in do becoming the norm eventually but not until the big s’s make them

 
Posted : 10/06/2025 12:21 pm
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I’m curious what is actually in the bottom bracket area of that demo. 
(Edit - Chrismac types faster than me)

but apart from the weird Spesh, most if not all of the other top riders are on factory teams with fairly big ties to either sram or shimano. 

Frameworks probably the most likely switch based on sponsors and ability to make frames quickly… but seems to go a bit against their ethos of making the greatest possible no gimmicks, simple 4 bar, non electronic suspension bike.

if I was buying a new big travel bike (let’s be honest I will never have a DH bike, but maybe a 170-180 travel with removable dropper…) it would be a gear box. 

although lack of maintainence, and mud friendly operation probably mean more to me than someone with a full time mechanic. 

 
Posted : 10/06/2025 12:26 pm
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I would guess that in the bottom bracket area of the demo is an enclosed version of what's on the pivot phenix, that's an uneducated guess with nothing to back it up fwiw...

 

I would further guess that the advantages of the gearbox are real, but in pure performance terms minimal.

maybe more 'feel' than anything else, like, If you put one of the fox factory riders on their rhythm level forks they won't be that much slower...

To me the big advantage is the lower maintenance and no mech smashing.... for WC riders with mechanics, the advantages are lower.

you don't see many smashed short cage mecs on the WC Circuit do you....

 

I for one hope that gearboxes are embraced as the gravity bike solution, and more investment and refinements improves this in short order.... but the downsides are well known.

 
Posted : 10/06/2025 12:39 pm
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Given Jackson Goldstone had 1.3kg 1.8kg of lead strapped to his downhill bike, there certainly isn't a weight penalty from them.

That would significantly lower his CoG considering how light he must be. A definite gain right there, but he's also got 500g of mass damper on the fork so how much would that affect the front end?

That leaves me wondering how much ballast Laurie Greenland and Troy Brosnan have on their bikes? 

Anyway back on thread. Oli Clarke, who is no featherweight deserves more attention for his achievement in Leogang. He's certainly proving a point, as do Charlie Hatton and  Tuhoto for being Elite finalists. 

 
Posted : 10/06/2025 12:43 pm
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I think people would be daft to buy one at the minute. They have not won a race yet, or been used in Enduro

 

A race team will be getting support and parts replaced every race 

 

Then again bike companies have been happy for customers to do the R&D on e-bikes and like mugs we have all said that’s ok 😂

 
Posted : 10/06/2025 12:52 pm
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They have not won a race yet, or been used in Enduro

Hattie Harnden won an enduro world cup round on a gearbox Nicolai this year.

 
Posted : 10/06/2025 12:56 pm
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Presumably interest in sticking a gearbox on a DH bike accelerated significantly when Gates put up €100k for the first winner on a belt drive? 

 
Posted : 10/06/2025 2:01 pm
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Joe Breeden is doing well on his belt driven Intense. He's made every finals so far and straight through in Q1 at the 1st 2 rounds and is 13th in the overall at the moment.

Very interested to see how the gearbox bikes go at VDS in a couple of weeks. If the suspension really does work better on these bikes then it should pay dividends on 4 minutes of roots.

 
Posted : 10/06/2025 2:21 pm
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"in DH where centralised mass down low helps with stability I can see it growing and becoming normal."

There's a good article by Seb Stott which explains how lowering the CoG of the bike towards the BB doesn't increase stability, it actually increases agility, because you reduce the polar moment of inertia around the longitudinal axis. Adding mass to do so increases the sprung to unsprung mass ratio, so you end up with a bike that is more stable vs external forces that act on the suspension but easily to lean over for cornering/scrubbing etc.

 
Posted : 10/06/2025 2:42 pm
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Presumably interest in sticking a gearbox on a DH bike accelerated significantly when Gates put up €100k for the first winner on a belt drive? 

I think that's led things down the wrong path to some degree. For a DH bike I'd take a nice, chunky, singlespeed chain over a belt. I can't see any benefit from running a belt, other than potentially financial

 
Posted : 10/06/2025 2:50 pm
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I can't see any benefit from running a belt, other than potentially financial

Yep I remember watching a vid at Dyfi with one of the Atherton riders. He said there were 2 gearboxes available and both had gears they didn’t use

 
Posted : 10/06/2025 2:53 pm
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Belt probably quieter than a chain?

 
Posted : 10/06/2025 2:56 pm
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Yep I remember watching a vid at Dyfi with one of the Atherton riders. He said there were 2 gearboxes available and both had gears they didn’t use

Not using all your gears is pretty normal in DH. I meant gearbox + chain over gearbox + belt

Belt probably quieter than a chain?

 
Not by a huge amount as you dont have extra length to try and tame like you do on a mech setup. I'm sure there's also a good reason why you almost exclusively see chain drive on off-road motorbikes
 
Posted : 10/06/2025 3:04 pm
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There definitely seems to be issues with belt retention in rough muddy conditions (like Poland). Several of the teams have been 3d printing extra guards to reduce mud ingress. I'm surprised no one is running shrouds around both main cogs to keep them locked in between 0 / 180 degrees.

No doubt Gates will be working on these issues themselves, maybe different cogs, or belt shapes like a narrow wide equivalent. 

I do think gearboxes are the future for DH but when SRAM / Shimano come out with one, I expect them to run chains. For someone like me though? A belt makes sense for the lower maintenance / durability.

 
Posted : 10/06/2025 3:48 pm
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3 races and already the "where are the results" calls are coming in.  🙄 

Trad drivetrains have had 30 odd years of investment and they have effectively blocked anyone trying anything new so for a while everyone is going to be playing catch-up. Add to that that the fastest racers are still on trad bikes and the belt/gearbox gains are marginal and you have where we are.  

The Honda won races even though it was tiny (relative to the riders and current standards) and had a very draggy drivetrain. 

No team with any significant Sram/Shimano sponsorship is going to jeopardise that for the moment.  If when the gaps start to form, that may well change.

 

Posted by: kamakazie

No doubt Gates will be working on these issues themselves, maybe different cogs, or belt shapes like a narrow wide equivalent. 

The Gates belt already has a centre track that does this. It's a very smart system.

The retention issue was, I'd suggest, a bike design issue.  there's no reason for the light, low momentum belt to do anything but go with the suspension unless it gets knocked off by some other force and with only 3 seconds between in and out, I imagine that kind of event would kill any run anyway. 

 

Posted by: mashr

I think that's led things down the wrong path to some degree. For a DH bike I'd take a nice, chunky, singlespeed chain over a belt. I can't see any benefit from running a belt, other than potentially financial

Other than it's lighter which has suspension benefits and noise benefits.  A chain is just a likely to get derailed as a belt and in some ways more so as it has more momentum to do so if things go sideways. You'd still need a tensioner and it'd have to work a lot harder.

 
Posted : 10/06/2025 4:13 pm
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Posted by: Speeder

3 races and already the "where are the results" calls are coming in.  🙄 

I'm not sure how you read that from the posts.

I'm genuinely curious as to peoples thoughts as I've been chatting to one company and it's not an insubstantial amount of cash to spend 


 

 
Posted : 10/06/2025 4:29 pm
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The Honda bike from 20 years back had a gearbox. Made no difference to the bikes people ride everyday. 

 
Posted : 10/06/2025 4:36 pm
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Posted by: thols2

The Honda bike from 20 years back had a gearbox. Made no difference to the bikes people ride everyday. 

 

It kind of had "gears in a box" as opposed to a gearbox

 

 

 
Posted : 10/06/2025 4:50 pm
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It also wasn't for sale, so impossible to say if it would've had an impact (it certainly would've been bought by DHers if the price was close enough to the competition)

 
Posted : 10/06/2025 4:54 pm
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Posted by: weeksy

I'm not sure how you read that from the posts.

I'm genuinely curious as to peoples thoughts as I've been chatting to one company and it's not an insubstantial amount of cash to spend 

Sorry was a bit harsh. Should have had one of these 😉 

 

I think they will be come THE thing in DH - it has every advantage and very few downsides.  If you were given a clean slate and were told to start a design from scratch with belt and chain as your options and all the bits are available off the shelf, you'd go G'Box/Belt. No question. 

 

I think it'll take a bit of time to bed in but as soon as it's shown to be faster in back to back, the riders will demand it. 

 
Posted : 10/06/2025 4:55 pm
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Posted by: thols2

The Honda bike from 20 years back had a gearbox. Made no difference to the bikes people ride everyday. 

That wasn't a proper gearbox - hunt down the video of it's internals.

Inside-Honda-MTB-Gearbox-Drivetrain-768x463.jpeg

https://www.cyclingabout.com/inside-the-revolutionary-honda-bicycle-gearboxes/

 

 
Posted : 10/06/2025 4:56 pm
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Posted by: Speeder

Posted by: kamakazie

No doubt Gates will be working on these issues themselves, maybe different cogs, or belt shapes like a narrow wide equivalent. 

The Gates belt already has a centre track that does this. It's a very smart system.

The retention issue was, I'd suggest, a bike design issue.  there's no reason for the light, low momentum belt to do anything but go with the suspension unless it gets knocked off by some other force and with only 3 seconds between in and out, I imagine that kind of event would kill any run anyway. 

Yes I'm aware of the centre track and it looks neat for most purposes, but is it effective enough at WCDH level? It's not the first time belt retention on WCDH bikes has been raised & several of the bikes in the pits run at least 1 if not 2 additional retention devices )not including the tensioner).

 

 
Posted : 10/06/2025 4:56 pm
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Posted by: Speeder

The Gates belt already has a centre track that does this. It's a very smart system.

The retention issue was, I'd suggest, a bike design issue.  there's no reason for the light, low momentum belt to do anything but go with the suspension unless it gets knocked off by some other force and with only 3 seconds between in and out, I imagine that kind of event would kill any run anyway. 

 

Quite a few of the PB shots in the pits recently showed team adding covers/bodges to keep mud off the belts - mud/stones getting underneath and into the teeth was a problem early on with belts, could even break them. Didn't think it was a problem with newer setups, but wondered when i saw those pics

 

 
Posted : 10/06/2025 5:28 pm
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Posted by: Speeder

I think it'll take a bit of time to bed in but as soon as it's shown to be faster in back to back, the riders will demand it. 

I don't even think for us that's what's holding us back from it, it's more the concern of buying one and something happening that we can't fix quickly, especially with back to back races over 3 weekends that we could possibly end up missing all 3.

However arguably we'd only miss one and borrow/hire/find something for the others 😀 

 

 
Posted : 10/06/2025 5:31 pm
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If I was racing as a  privateer I wouldn’t go gear box at the moment, but then I’m massively cautious of anything new in the bike world! Maybe if you buy a bike with one and it came with a spare so if/when it falls to bits you can still ride the following weekend but can’t see that happening 

 
Posted : 10/06/2025 5:39 pm
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I feel the same as I do when I see a pro rider absolutely bombing it on a DH track without a chain (or belt) at all… 

 
Posted : 10/06/2025 5:51 pm
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Gearbox on a DH and Eeb - Yes from me. Belt drive? Nope. Hard to beat a good old chain that can crush and squish mud, grit and sticks.

Unless you go fully enclosed:

image.png

 
Posted : 10/06/2025 6:06 pm
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Had a couple of different design gearbox DH/freeride/enduro bikes now (still got one) and whilst I haven’t tried the electric shift under power latest pinions, I’m not in any hurry to buy another. Mechs and chains work well enough for me.

 
Posted : 10/06/2025 6:30 pm
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To me the big advantage is the lower maintenance and no mech smashing....

Until something goes wrong.

How user-serviceable are they, what will parts availability be like in five years time and how interchangeable are they? 

I can take my Shimano shifter and mech off and fit a SRAM or Microsoft or whatever one instead to the same frame. I can rebuild a mech myself and I can set them up myself if I change cable or whatever.

I like the gearbox idea but I doubt that the manufacturers will be making everything compatible with everything else because they don't seem able to do it now and I don't want to be binning a three ear old frame when the gearbox fails 

 
Posted : 10/06/2025 8:23 pm
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Interesting analysis (which i'm not going to do) would be to look at the performance of the riders who have moved from chain bikes to belt bikes.

Reece Wilson claims to have been an instant convert but obviously hasn't demonstrated any gains at races yet.

I also wonder if the benefits are likely to show up more in the EDR than DH world, where the longer tracks and increased requirement for durability. Harnden's result doesn't really help given she's so damn good on any bike.

 

Posted by: chrismac

The question I guess is has a gearbox bike not won yet because in many cases those more likely to win are not on bikes with them.

I agree with this. I don't think we've seen any riders do badly because they're on a belt&box bike

 

 
Posted : 10/06/2025 10:34 pm
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Posted by: reeksy

Reece Wilson claims to have been an instant convert but obviously hasn't demonstrated any gains at races yet.

His performances have been a little disappointing given the hype surrounding the new team and that they seem to have put together a dream package but in reality he's still coming back from injury and is now a rider AND team manager. That's a lot of work and it's going to be a distraction. I hope he gets back up to speed because he's a hell of a rider.

Charlie Hatton has said pretty much the same about the new Atherton. I doubt they'd be riding it if it wasn't at least as fast as the regular bike.

 

 
Posted : 10/06/2025 11:07 pm
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It’s an interesting development, for sure and the drawbacks of gearboxes can be advantages on a DH bike.

That said I personally think that the improvement that they make to the bike wouldn’t be enough to upset the order at any level of the sport.

I’m of the opinion, based on nothing more than a hunch, that mastering suspension setup using telemetry and advances in smart shocks would have a bigger impact on the performance of the actual bike than gearboxes.

at the end of the day, it is the humans in the team that win a bike race.

 
Posted : 11/06/2025 12:34 am
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Posted by: reeksy

Reece Wilson claims to have been an instant convert but obviously hasn't demonstrated any gains at races yet

Not at the top end anyway, but he took the first SDA round on his gearbox bike, I think Stan Nisbet was on one too and won juniors. Though tbf Stan Nisbet would win races on a spacehopper. He was 3rd at the IXS Fort William round, Reece was 9th- Charlie Hatton won it by a pretty big margin but now I think of it I've no idea if he was on the gearbox bike. Reece is a contender of course but he's not a consistent top runner- he's got IIRC 1 win at snowshoe a few years back and a third, and obviously the champs. So it's not like we can draw anything from it either way, he's always been capable of a wildcard win.

Reminds me a lot of when the 29ers started to arrive in a meaningful way, it took a while to get a podium and people were very critical of that but it was immediately obvious they were capable of it. I won't quite say just a matter of time, that's not really how racing works, but it wasn't far off.

 

 
Posted : 11/06/2025 1:23 am
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Charlie has been on it for everything. 

Even the Not A Race at BPW which he won.

https://www.rootsandrain.com/event14442/2025-mar-26-bikepark-wales-not-a-race-bikepark-wales/results/#h-openm

George MAdley has only recently got his after using Charlies old blue bike before from the end of 2024. 

Stan and Reece have been exclusively on theirs since the start of the year, as has Henry, Monica and Hattie.  

I don't think the gearbox has held anyone back in terms of performance yet, everyone is doing about what would be expected of them usually, possibly Charlie you'd argue hasn't quite performed as you'd have hoped, but with the levels at the top end being what they are and the runs needed to do so, that's really hard to say as well as it's sooooooo fast at the sharp end. His IXS at Fort William though was massively impressive with a 4s win 

 
Posted : 11/06/2025 6:29 am
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Reminds me a lot of when the 29ers started to arrive in a meaningful way, it took a while to get a podium and people were very critical of that but it was immediately obvious they were capable of it.

I was thinking of the 29er comparison as well.

But I think they were more of a clear-cut advantage at the time.

I think it was Santa Cruz dominated qualifying in their first race on them, but then it rained in finals and they couldn't back it up the next day.

The level of riding is so high now, I feel it's harder for a single rider to dominate anyway. Even if they did have a slight advantage on their bike.

Report

Interesting analysis (which i'm not going to do) would be to look at the performance of the riders who have moved from chain bikes to belt bikes.

That Pinkbike guy who does all the stats reports should do this! Would be more interesting than their usual death-by-graphs race analysis.

 
Posted : 11/06/2025 8:12 am
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Posted by: FunkyDunc

I think people would be daft to buy one at the minute. They have not won a race yet, or been used in Enduro

 

Nicolai have been running them on their bikes for a while. And if you have a look at the pinkbike article from the other day where they compare bike weights, it actually is very comparable with traditional drivetrain bikes.

As far as how I'm feeling about gearbox bikes in general, same as I felt last week/month/year - totally indifferent. I can see the benefits but I can also see the benefits of the traditional setup too.

 

 
Posted : 11/06/2025 9:00 am
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I don't even think for us that's what's holding us back from it, it's more the concern of buying one and something happening that we can't fix quickly, especially with back to back races over 3 weekends that we could possibly end up missing all 3.

Reliability wise I'd personally not be too concerned with the gearbox itself, which seem to be pretty robust.  It's all the other gubbins on the bike to route the chain / belt that I'd be worried about.  You've had issues with the Trek idler and it still seems it's a part that needs regular attention, on gearbox bikes it appears that there are a lot of rollers and guides, often custom items, which creates more risk and maintenance and teams still seem to be finding their way in terms of reliability and poor weather performance over a race weekend.

 

 
Posted : 11/06/2025 9:29 am
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Posted by: razorrazoo

I don't even think for us that's what's holding us back from it, it's more the concern of buying one and something happening that we can't fix quickly, especially with back to back races over 3 weekends that we could possibly end up missing all 3.

Reliability wise I'd personally not be too concerned with the gearbox itself, which seem to be pretty robust.  It's all the other gubbins on the bike to route the chain / belt that I'd be worried about.  You've had issues with the Trek idler and it still seems it's a part that needs regular attention, on gearbox bikes it appears that there are a lot of rollers and guides, often custom items, which creates more risk and maintenance and teams still seem to be finding their way in terms of reliability and poor weather performance over a race weekend.

I think all DH bikes that are raced regularly take a fair bit of upkeep. The Pro bikes less/more in the context that they're clearly getting replacement parts constantly, you can see if in the Tech Randoms on PB, they're getting new brakes 5-6 times a year, new bushings, rebuilds of XYZ etc etc. So they don't need upkeep in terms of the privateer/random bikes where you're replacing stuff as it wears out. Ideally i'd swap the pivot bolt or idler every 6 weeks for example, but that's £100. So you just run them till they die and swap, but that arguably then looks like it needs more attention. 

I chat regularly to people who run Zerodes and they don't seem to need much in truth, less than some bikes i'd argue.

Now that we've got to grips with our Session a bit more it's taking less upkeep than previously, with things like pivots/bearings you now get more of an idea which is needing replacing (usually the pivot bolt rather than the bearings).

We've pretty much moved away from the gearbox bikes for the boy at the moment, especially with his new frame coming in this weekend, but it's interesting to get other peoples thoughts on them.

 

 
Posted : 11/06/2025 10:01 am
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There's a good article by Seb Stott which explains how lowering the CoG of the bike towards the BB doesn't increase stability, it actually increases agility, because you reduce the polar moment of inertia around the longitudinal axis. Adding mass to do so increases the sprung to unsprung mass ratio, so you end up with a bike that is more stable vs external forces that act on the suspension but easily to lean over for cornering/scrubbing etc.

That's some sloppy word soup right there............

First up "polar moment of inertia" is nothing to do with what we're talking about, rather confusingly is has nothing to do with ' moment of inertia". The first is an objects resistance to torsional deformation, the latter is related to angular momentum, which is probably what you meant.

Second, adding mass at the axis of rotation does not reduce the moment of inertia. Moving mass there would, but just adding it doesn't. You can calculate it experimentally as (and IMO it's easier to visualize) moment of inertia = torque applied / angular acceleration, i.e. the resistance something has to being spun. To calculate it theoretically is harder, but it's the sum of the mass times the distance from the axis squared all the infinitesimal elements that make up the system.  So if you choose to think of the BB as axis, the rear cassette is 250g and 0.5m from the BB then it's moment of inertia is 0.0625kg.m^2.  If you make the BB 1.8kg then that 1.8 x 0^2 = 0.

I would argue the opposite of your point, in an off road bike (NOT AN F1 CAR) adding mass at the BB increases stability around the longitudinal axis because you're not so bothered about the bikes ability to rotate around a corner*.  Adding mass at the BB directly between the wheels means that when there's a lateral impact on on one wheel, the other becomes the axis of rotation, so having mass between them resists that rotation. If your rear wheel gets kicked sideways, the front doesn't move in the opposite direction, there's a force there, but it's resisted by the tyres grip. If the other wheel is off the ground then it's different, but then the bike will probably try and rotate around the center of mass (you) and having weight at he BB achieves the same thing, just in a different axis. And by having the mass low down you effectively move the sagittal axis down with it, so that sideways impact will tend to push the bike sideways, not rotate the bike sideways underneath you.

TL:DR - it can't make the bike more agile, it can make the bike bike less agile in certain planes/axis but not others, and as a result you could definitely change how the bike reacts to certain forces from the ground.

And therefore I'd conclude that it's not a performance thing, weight should** probably always slow you down. But it could definitely be because an e-bike feels very different and they've been using those for the majority of their training. And having a  bike that handles in a familiar way is probably worth more time than is lose having to accelerate that weight around. 

 

*to get round a corner a car has to do two things, it has to change the direction it's traveling in, and it has to rotate. A 1ton F1 car takes a lot of force just to rotate it, a 10kg bike you can whip sideways in the air. And things like lean angles complicate it because you're rotating the bike in 2 dimensions.

**then again it's downhill, so maybe

 

 

 

 
Posted : 11/06/2025 10:30 am
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There's a good article by Seb Stott which explains how lowering the CoG of the bike towards the BB doesn't increase stability, it actually increases agility,

think I remember that article - does it use the analogy of balancing a broom on the palm of your hand? its easier (more stable) to do with the broom head at the top than with the head at the bottom, although if you did have the mental reactions to do it at the bottom it would require less physical effort.

Although to bring it back to bikes, just saying stable or agile in terms of the mass, forgets that it is also a 2 wheeled machine moving forwards.

Consider the two extremes.

1) a 2005 20lb hardtail, rider stood up tall (no dropper), 10kg camelback on.

2) modern gravity sled, 40lb bike, all the weight as low as can be. 1500g 29er tyres giving gyroscopic stability at speed, 250mm dropper (or DH seat height) with rider able to crouch and move at will.

By the broom/Seb's method, bike 1 is "stable". But thats counteracted by the 70 degree head angle which gives it lots of agility.

Bike 2 is "agile" in the sense that you can pretty much steer with your body, point it at any line you want. But that is counteracted by the slack head angle and 1400mm wheelbase an wheel innertia which returns stabilty to the system.

Go pile a load of weight on bike 1 and you've got (an old man beardy 4 pannier touring set up) a very difficult to manage bike thats limited to easy terrain.

Magically make bike 2 weigh 20lbs, (think dangerholm got a DH bike to about 27lb with DH tyres, so picture that wearing XC rubber) and you have something that I imagine takes a lot of mental effort/microadjustments to keep on track, although overall its less weight to move around.

Although, as with everything bike related, the rider weight and size makes such a difference. Whats the CoG of Richie Rude vs Jackson Goldstone? Moir vs Melamed? or Pidcock vs Scharzbauer? Playing with a few kilos of mass on the bike frame isn't going to overcome those differences. People only have their own body as a frame of reference and adapt to what they know.

 
Posted : 11/06/2025 10:52 am
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TL:DR - it can't make the bike more agile, it can make the bike bike less agile”

I’m really busy running my own business so don’t have time for an essay, which is why my previous post was written very quickly, and that phrase was technically incorrect even though that phrase could mean exactly the right thing because of the actual words in it!

(Consider the definition of “inertia”)

My point was about moving mass towards the BB,  not adding mass. Lowering the CoG of a bike reduces the distance it has to move when you lean the bike over, therefore meaning less force is required, therefore you increase agility.

So many people saying “lowering the shock in the frame makes the bike more stable” but it doesn’t. Obviously added mass doesn’t increase agility.

 
Posted : 11/06/2025 11:22 am
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I still think that it makes more sense for gearbox bikes to have the drivetrain fully enclosed. Similar to the Millyard bike. Totally isolate it from mud and debris. 

I think gearbox DH bikes make 100% sense a friend has had a Zerode Taniwa for a few years and it’s been faultless. 

 
Posted : 11/06/2025 12:25 pm
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Posted by: chiefgrooveguru

My point was about moving mass towards the BB,  not adding mass. Lowering the CoG of a bike reduces the distance it has to move when you lean the bike over, therefore meaning less force is required, therefore you increase agility.

So many people saying “lowering the shock in the frame makes the bike more stable” but it doesn’t. Obviously added mass doesn’t increase agility.

another can of worms opened here...

while there are two different issues on CoG - system CoG including the rider, and bike CoG.

Overall bike CoG is probably most important to overall speed etc.

But bike CoG maybe more important for "feel"

You are moving the bike around underneath you (or having it moved by external forces).

Realistically that is felt through the feet - so at BB height. So if the CoG of the frame is further above that point, it will feel like it takes more effort to move. Also the gyroscopic effects of the wheels are going to have an effect, and one that is applied at axle height.

 

 
Posted : 11/06/2025 12:32 pm
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The waffle about weight/CoG and geometry is 'interesting' enough I suppose but coming back to the original question about how the current lot of Gearbox DH bikes being ridden at 2025 WC rounds might influence the wider future market for MTBs, I suppose the question is more what appetite do privateers and muggles have for gearbox bikes?

Offhand I'm sure everyone who's ever owned and had to maintain any MTB (especially a DH bike) would be very enthusiastic about the idea of not having a gear dangler on the back to catch rocks, But I have to question the reality of it. Gearboxes have been on the horizon for 20 odd years now, but the available solutions have always come with compromises and price tags that never quite seem appealing enough for mass adoption.

These days I still think there's a problem with common mounting standards, or a lack thereof (correct me if I'm wrong here). I see a similar issue with mid-drive E-bikes and there is some potential to help align all the miscellaneous things people might want to bolt into a frame instead of a BB and nudge the world a bit closer to gearboxes that way...

I also question the inherent loss of efficiency in most gearboxes, but I think a fair few would accept that compromise if pricing was on par and maintenance burden was reduced... But is that what we'll be offered?

Then there's the issue of just how many DH bikes are being sold each year, or not. Is there really the worldwide market now for relatively "non-standard" (and therefore more expensive) DH bikes? Is DH really a growth market? or should the effort be expended on Enduro and E-MTBs where more punters seem inclined to throw their money now...

Do Gearbox DH bikes necessarily translate to Gearbox Enduro and Trail bikes? Yes they exist, but they're not a product for the masses still... 

Despite a WC DH field full of fancy new toys, I'm not sure the bike buying public are any closer to affordable Gearbox bikes today than they were five years ago...

 
Posted : 11/06/2025 12:39 pm
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Posted by: cookeaa

Despite a WC DH field full of fancy new toys, I'm not sure the bike buying public are any closer to affordable Gearbox bikes today than they were five years ago...

Well the Zerode is £8500 and the Gamux is about £10500. Both are expensive yes, but not completely insane in the current market of elite level bikes.

 

 
Posted : 11/06/2025 12:41 pm
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I always wondered why singlespeed DH bikes never became a thing.

If I was in the market for an out and out downhill bike I'd definitely be giving Starling a call to see if they would make a Sturn 🙂

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Posted : 11/06/2025 12:52 pm
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