Just say no to 29ers

[Marc_250]

I got a a Ghost eMTB with a 29 front and 27.5 rear a few weeks ago to make sure I covered both basis

 

[Al Boneta]

I got a a Ghost eMTB with a 29 front and 27.5 rear a few weeks ago to make sure I covered both basis

Smart thinking

 

[The Flying Dutchman]

Dear diary,

Today as a grown-ass man I argued with other grown-ass men on the internet about what wheel diameter is the betterer for an electrically-assisted mountain bike. I fear I have not persuaded anyone today that my wheel size is superior, but tomorrow we fight on.

May my keyboard strike true

Sincerely yours,

{you}

 

[slippery pete]

I say no to 29ers that turn ebikes in a mainstream product.

Mainstream = bad? That is a philosophy of "pioneer exceptionalism". e.g. "You're only a proper EMTBer if you got an early one before the bugs were ironed out and they all began to look like Treks. BORING!!!"

Because...
... a 29er is way more railed than a 27.5
... and a 455 is way more stable than 440 etc etc

Those are contributory factors in an entire package of geometry. You keep isolating single parameters and extrapolating general conclusions. That's why your argument is a dead duck. You seem to imagine a single way of riding that is *proper* and an ideal ebike specification to facilitate *proper riding* by *proper riders*. That is the philosophy of exceptionalism again. The truth is that ebikes offered on the market promise a range of capability and riding styles (most importantly, colours) for a range of riders - big ones, small ones, park rats, back countryists, pootlers, weekend warriors, enduro wannabes... It is a burgeoning market and, yes, marketing will take place.

ebikes are getting
... easier,
... safer

That's a bad thing? Oh, I get it. Exceptionalism again. ebikes *must* be difficult and unsafe to ride otherwise they're not proper ebikes.

... not faster

Is this a race? If racing, is it really true that racers do not prefer 29ers? Some do? Some don't? If not a race, maybe you're making a "weight" point.

Statement: 29ers will have some components carry more weight than 27.5er equivalents.
Q: How much?
A: It is a linear relationship.

e,g, Taking ETRTO as the measure, the difference between 584 and 622 is 6.5%. We can imagine 6.5% more weight for tyre. 6.5 % more weight for rim. 6.5% more weight for spokes. That will be a slightly flexier wheel. To counter that you might build your wheels with 4 extra spokes per wheel at which point the wheel will be stiffer at a further ~12-13% increase in spoke weight. So 6.5% for tyre. 6.5% for rim, 20% for spokes. 2kg tyres get 130g heavier. 1.2kg rims get 78g heavier. 400g of spokes get 80g heavier (20%). That is the total. ~288g. If you're coping with flexier wheels (with the same spoke count) it would be ~234g.

Now where I think it gets interesting is when you take into account the trend we've seen where 27.5ers have been specced with bigger tyres (even plus sizes) to make up for not gripping as well as 29ers (you used the word "rails"). And those bigger tyres are... heavy, flexy and imprecise. For a certain type of rider it is quite possible for 29ers to be lighter, stiffer, grippier and better suited to a particular riding style through choice of tyre (and maybe spoke count).

So the weight argument is moot. It remains a parameter that cannot be taken out of context of the whole ebike specification. Once again, the market exists and the market is served. Marketing will be a factor.

I kinda get your point on integrated batteries. We do seem to be seeing many brands (not all) pick up a weight gain when they've gone integrated. We also see a three way battle between : 1. designs that facilitate battery removal (off-bike charging); 2. designs that look sleek; and 3. designs that don't need extra structural material (fixed battery). If you have electric power in your shed/garage, off-bike charging won't be an issue. If you do need a removable battery it might be a feature that costs some weight gain or a less sleek (non-integrated) look. If you session laps and want to swap batteries, it is a different need to someone seeking the longest range on a single fitted battery with the lowest whole system weight. Again, the variations in the market exist. The market is served. Marketing will be involved.

Side note:
I find the rush to carbon construction at the top end to be a disappointment. The weight saving is deeply in the realm of diminishing returns. ebikes have the opposite of a proven track record for long service life. The wear and tear and onset of reliability/maintenance issues means that ebikes transition rapidly from factory to landfill. Maybe the economics will level out but for now a carbon ebike is essentially a disposable item with a large environmental impact.

...or funnier

If that is a chainstay point, I'll refer you to my previous answer. The whole package is important.

We have seen the broader MTB concerns of long/low/slack geometry transition over to eMTBs in the current generation. eMTB has become more acceptable to a broader swathe of the existing population of analog MTBers. There may well be a shift in the eMTB riding demographic. Different riders seeking different things from their rides. Variations in the market exist. The market is served. Marketing will be involved.

 

[GrandPaBrogan]

I've run out of pop corn...

.

 

[knut7]

I've run out of pop corn...
.

Have you tried cauliflower? That's allegedly an amazing popcorn substitute!
https://www.organicfacts.net/popcorn-substitutes.html

 

[Eddy Current]

Mainstream = bad? That is a philosophy of "pioneer exceptionalism". e.g. "You're only a proper EMTBer if you got an early one before the bugs were ironed out and they all began to look like Treks. BORING!!!"



Those are contributory factors in an entire package of geometry. You keep isolating single parameters and extrapolating general conclusions. That's why your argument is a dead duck. You seem to imagine a single way of riding that is *proper* and an ideal ebike specification to facilitate *proper riding* by *proper riders*. That is the philosophy of exceptionalism again. The truth is that ebikes offered on the market promise a range of capability and riding styles (most importantly, colours) for a range of riders - big ones, small ones, park rats, back countryists, pootlers, weekend warriors, enduro wannabes... It is a burgeoning market and, yes, marketing will take place.



That's a bad thing? Oh, I get it. Exceptionalism again. ebikes *must* be difficult and unsafe to ride otherwise they're not proper ebikes.



Is this a race? If racing, is it really true that racers do not prefer 29ers? Some do? Some don't? If not a race, maybe you're making a "weight" point.

Statement: 29ers will have some components carry more weight than 27.5er equivalents.
Q: How much?
A: It is a linear relationship.

e,g, Taking ETRTO as the measure, the difference between 584 and 622 is 6.5%. We can imagine 6.5% more weight for tyre. 6.5 % more weight for rim. 6.5% more weight for spokes. That will be a slightly flexier wheel. To counter that you might build your wheels with 4 extra spokes per wheel at which point the wheel will be stiffer at a further ~12-13% increase in spoke weight. So 6.5% for tyre. 6.5% for rim, 20% for spokes. 2kg tyres get 130g heavier. 1.2kg rims get 78g heavier. 400g of spokes get 80g heavier (20%). That is the total. ~288g. If you're coping with flexier wheels (with the same spoke count) it would be ~234g.

Now where I think it gets interesting is when you take into account the trend we've seen where 27.5ers have been specced with bigger tyres (even plus sizes) to make up for not gripping as well as 29ers (you used the word "rails"). And those bigger tyres are... heavy, flexy and imprecise. For a certain type of rider it is quite possible for 29ers to be lighter, stiffer, grippier and better suited to a particular riding style through choice of tyre (and maybe spoke count).

So the weight argument is moot. It remains a parameter that cannot be taken out of context of the whole ebike specification. Once again, the market exists and the market is served. Marketing will be a factor.

I kinda get your point on integrated batteries. We do seem to be seeing many brands (not all) pick up a weight gain when they've gone integrated. We also see a three way battle between : 1. designs that facilitate battery removal (off-bike charging); 2. designs that look sleek; and 3. designs that don't need extra structural material (fixed battery). If you have electric power in your shed/garage, off-bike charging won't be an issue. If you do need a removable battery it might be a feature that costs some weight gain or a less sleek (non-integrated) look. If you session laps and want to swap batteries, it is a different need to someone seeking the longest range on a single fitted battery with the lowest whole system weight. Again, the variations in the market exist. The market is served. Marketing will be involved.

Side note:
I find the rush to carbon construction at the top end to be a disappointment. The weight saving is deeply in the realm of diminishing returns. ebikes have the opposite of a proven track record for long service life. The wear and tear and onset of reliability/maintenance issues means that ebikes transition rapidly from factory to landfill. Maybe the economics will level out but for now a carbon ebike is essentially a disposable item with a large environmental impact.



If that is a chainstay point, I'll refer you to my previous answer. The whole package is important.

We have seen the broader MTB concerns of long/low/slack geometry transition over to eMTBs in the current generation. eMTB has become more acceptable to a broader swathe of the existing population of analog MTBers. There may well be a shift in the eMTB riding demographic. Different riders seeking different things from their rides. Variations in the market exist. The market is served. Marketing will be involved.

Thanks for this well detailed, respectful and argumented answer

Let me take cars again to explain myself

The Nissan GTR is a hell of a car. Is fast and nobody can say is a boring car, despiste it weights almost like a SUV and it’s has front engine and is a tall car, but is like you’re less important at the steering, it has 4wd auto gearbox, it’s turbo, all the electronic sensors ...

Take a manual GT3 Porsche, rear wheel drive, a car that’s requieres you to go fast.

This where i think the ebikes ahead, beautiness and gentle, not bad if you want it, not bad if it’s a bit, but SO BAD if all they goes that way, with the help of 29ers long chainstays etc ...

A bike doesn’t have to be boring because it’s 29er or it weights 23kgs but if it’s proper designed it’s going to be even funnier and probably fast with 27.5 and 20nkgs ... stop that kinematics magician thing ebikes are tending to go to the easy side, Sam Hill can drift a tank and maybe you and maybe Gary, but any single brand that developed a no compromise ebike release a 27.5 with sub450 chainstays and there you have the Norco Sight the Shuttle the Whyte the Rocky Mountain the Spectral and many more ... but at the next model there you go, L-EVOlution comes: 29er integrated and you know how the story goes.

What the media is going to say “is less nimble than the previous, honestly” ... no way

To summarize:

Ebikes are going mainstream. 29er is marketing. Is an XC thing that works in XC.

A good 29er can be agile, a good 27.5 is going to be even more agile!

Why you don’t just say, hey, that’s true but I prefer trade agility for stability? Ain’t easier than try to deny the evidence?

 

[outerlimits]

This thread reminds me of a song by The Living End

.......
Well we don't need no one to tell us what to do
Oh yes we're on our own and there's nothing you can do
So we don't need no one like you, to tell us what to do
We don't refer to the past when showing what we've done
Our generation gap means the war is never won
The past is in your head, the futures in our hands
'Cause I'm a brat
And I know everything
And I talk back
'Cause I'm not listening
To anything you say
And if you count to 3
You'll see it's no emergency
You'll see I'm not the enemy
Just a Prisoner of Society

 

[Beekeeper]

The marketers are going to just love this thread and will dine out on it for many years to come.

Get ready for the new standard of 28.25 inches coming to your local bike store very soon ?

 

[GrahamPaul]

The marketers are going to just love this thread and will dine out on it for many years to come.

Get ready for the new standard of 28.25 inches coming to your local bike store very soon ?

It's already here!

I've been watching this thread with mild amusement and much confusion... One of the other old codgers who comes out with us on the Friday morning coffee run has an e-bike. Not an eMTB. A straightforward e-bike that his partner bought him as a birthday present from Decathlon. So he can't really dump it without lots of hurt feelings.

This e-bike is meant for touring on the roads. We don't do much technically exciting on Fridays because otherwise they all get off and walk, but this particular bike has real problems with some of the sandy tracks that we do take.

For the laugh, last year I took my clockwork MTB full-sus over the Alpine passes on a road trip with a German mate of mine. He was on his German touring roadster. It wasn't long before the discussion/argument turned to wheel size and tyres. I'd fitted 2" Hurricanes to my twenty-niner. There didn't seem to be any difference in the wheel sizes between my 29" and his 28" x 2" tyres. A little closer inspection and, lo and behold, both sets of tyres on 622 rims. Basically the same wheel with a different size of tyre.

Point of the tale: I switched out the road tyres on the street e-bike for the Hurricanes that I no longer need. My 29" tyres quite happily fitted the 28" wheels and are good enough for the chap's competence level.

Thus, the size should really be "28-29 inches", no? So we already have 28.25"

 

[slippery pete]

A bike doesn’t have to be boring because it’s 29er or it weights 23kgs but if it’s proper designed it’s going to be even funnier and probably fast with 27.5 and 20nkgs

The weight difference between 29er components and 27.5 is in the realm of ~300g-500g. Getting a 3kg variance in bike weight is a lot more than picking a smaller wheel.
The difference between a 23kg bike and a 20kg bike is money; typically €3000. (NOTE: the Focus does it on battery capacity).

The same group of bikes vs wheel size shows the 29ers tend to be the lighter bikes...

But that may be because the selected group includes more expensive 29ers.

FWIW, I bought the cheapest 29er from this test.

 

[Mikerb]

Just read this thread! Having built and raced them I know a lot more about cars than bikes . Forgetting about engine power for a moment by far the most significant design element that defines ultimate performance is the chassis ( for a bike...frame design). Second is the position of centre of gravity and turing moment when the heaviest components are added ( including the driver/rider). Several different suspension designs deliver similar results (RS/Fox/air/coil) with tuning more important than design. Every attempt is made however to make the unsprung weight (wheels tyres hubs suspension and suspension arms) as light as possible whilst maintaining strength and stiffness. This becomes even more important the lighter the sprung weight is.
So we come to wheels and tyres. The most important consideration is the type of terrain the car is designed for. In general bigger diameter wheels and higher volume tyres for rougher terrain ......BUT......both chassis and suspension design will have specified in advance the overall diameter of wheel and tyre with only marginal room for variation. It is only when you push a car beyond its limits of adhesion that you find out how good or bad the overall design is. Stability, understeer/oversteer predictable breakaway, balance.....all contribute to speed. A leary car is not fast...its just an accident waiting to happen!
Summary.....performance comes from the sum of all the parts and a good design defines all those parts as an integrated package.

 

[Zimmerframe]

Opinion is not fact. What works for one person, will not work for every person.
If you find what works for you great, but don’t state your experience and anecdotal evidence as the way they things should be for everyone else.
Pick a wheel size and go on with your life.

I was hoping with your new persona, Al Burtoneta, we'd be getting a few more Burt quotes mixed in .. like :

Marriage is about the most expensive way for the average man to get his laundry done.

 

[Mikerb]

I was hoping with your new persona, Al Burtoneta, we'd be getting a few more Burt quotes mixed in .. like :

Marriage is about the most expensive way for the average man to get his laundry done.

You could get whipped with stretched chain for saying that in the new world order

 

[Zimmerframe]

You could get whipped with stretched chain for saying that in the new world order

True.. please insert person or thing, instead of man.

 

[118]

 

[GrandPaBrogan]

^ Oh man, I just lost it laughing.

Scary that a component of that is true - in every consumerist industry.

 

[Ananda]

I detest all ready made ebikes. I am all in for analogue bike conversions even if they have no torque sensors. Long live bafang.

Opppps I am in the wrong thread!

 

[CjP]

That’s the best laugh ever!

 

[Mcharza]

Haha, mostly so true

 

[Eddy Current]

Hey you stubborn sons of the perfide Albion ... im back. Iiiiiiih ihihihiii ... ay!

Do you remember the Pivot Shuttle? For many the best ebike.

Conclusion (2018)
The Pivot Shuttle has proven to be a successful foray into the eMTB segment for the American brand. They’ve created a bike for riders who are primarily looking to have a lot of fun on the downhills, excelling there with its simultaneously playful and composed handling. Details such as the overly complicated battery integration and small weaknesses in the spec, however, cloud the otherwise positive impression. The price is hefty, of course, though it promises exclusivity.

Pivot Shuttle Review | E-MOUNTAINBIKE Magazine

Guess what they do for the 2020? Aaaaajajaja ... ay!

And the same web that rated the best handling machine a year ago is now a crap with (29) wheels .... ahahahahaaaaah ... ay! And they made it more comfy with shorter reach and higher stack aahahahahaha ihhhhhiiiiii ... ay!

Conclusion (2019)
The name of the Shuttle promises more than the bike can deliver: it’s nerve-racking on steep descents and isn’t composed to enough for rough terrain and big hits when compared to the best bikes in the test field. This is surprising since Pivot are known for their awesome enduro, freeride and DH bikes. As well as that, the battery concept is now outdated, which given the € 10,499 price tag is no longer justifiable. If you’re looking for a lightweight and comfortable eMTB for flow trails and more moderate climbs and descents, you will find the Pivot an expensive but well-suited companion.

Pivot Shuttle 29 Team XTR in Review | E-MOUNTAINBIKE Magazine

 

[outerlimits]

Hey you stubborn sons of the perfide Albion ... im back. Iiiiiiih ihihihiii ... ay!

Do you remember the Pivot Shuttle? For many the best ebike.

Conclusion (2018)
The Pivot Shuttle has proven to be a successful foray into the eMTB segment for the American brand. They’ve created a bike for riders who are primarily looking to have a lot of fun on the downhills, excelling there with its simultaneously playful and composed handling. Details such as the overly complicated battery integration and small weaknesses in the spec, however, cloud the otherwise positive impression. The price is hefty, of course, though it promises exclusivity.

Pivot Shuttle Review | E-MOUNTAINBIKE Magazine

Guess what they do for the 2020? Aaaaajajaja ... ay!

And the same web that rated the best handling machine a year ago is now a crap with (29) wheels .... ahahahahaaaaah ... ay! And they made it more comfy with shorter reach and higher stack aahahahahaha ihhhhhiiiiii ... ay!

Conclusion (2019)
The name of the Shuttle promises more than the bike can deliver: it’s nerve-racking on steep descents and isn’t composed to enough for rough terrain and big hits when compared to the best bikes in the test field. This is surprising since Pivot are known for their awesome enduro, freeride and DH bikes. As well as that, the battery concept is now outdated, which given the € 10,499 price tag is no longer justifiable. If you’re looking for a lightweight and comfortable eMTB for flow trails and more moderate climbs and descents, you will find the Pivot an expensive but well-suited companion.

Pivot Shuttle 29 Team XTR in Review | E-MOUNTAINBIKE Magazine

Yawn ?

 

[knut7]

So other factors, like the 363mm BBH has got nothing to with why the Shuttle performs worse on the descents??

 

[04fuxake]

26", 27.5", or 29" - it doesn't matter what your preference is.

 

[paquo]

26", 27.5", or 29" - it doesn't matter what your preference is.

I switch between a rigid 26, full squish 26 and 29 and the levo, i like them all

 

[Rusty]

So - the Pivot is a shit ebike compared to others .... happens all the time and wheel size has nada to do with it. A friend with the 2018 Pivot doesn't really like it at all compared to his 2017 Levo 27.5. Like everything - it is all down to ones perspective .... or in the case of a Magazine the editors perspective.
Did many MX bike shoot-outs in the mid 70's for several magazines and quite often what was decided as the best was not the one the riders preferred.

 

[paquo]

this is a 29er, it is utterly and completely lust worthy

 

[Rusty]

this is a 29er, it is utterly and completely lust worthy

ummm - looks like they forgot the motor ...............

 

[jooles]

Been riding a 29er for nearing 10 years now (Gary Fisher originally). My non Emtb is an Enduro 29er which is superb. Agile (if you learn how to turn a 29er by cranking it over) does roll over stuff well when you mess a line (which I do a lot) and are IMHO popular for a reason thats more than just marketing hype.

As mentioned above 27.5 came in to fill the gap between 26-29. I've had 27.5 bikes and just didn't feel that much difference to 26". Perhaps as I was used to 29" ?

From experience 27.5 in the back is fine - the old wheelbarrow rollover syndrome. Where 29 seems to shine is up front. Liteville were pioneering this with variable length rear chainstays. From memory UCI DH rules didn't allow mixed wheel sizes ? It seems Emtb geometry is as much governed by motor size as it is wheel size.

As with many sports, it is what you are used to: It takes a while to adjust, more than just a few rides. Just like jumping onto an eMTB after being on an "analog" for many decades.

A 27.5 wheel with 2.8" tyre is nearing a 2.35 Magic Mary shod 29". An eMTB especially the 29/27.5 setup with a big tyre on the back really seems to work well for traction and putting down torque on the steep climbs. On the DH stuff the rear 27.5 wheel is a little stiffer than the 29 making the back end feel a little more taught.

I bought a cheap Diamond Back ranger about a year ago to dip my foot in the electric pond: E8000/Yari/XT/Mondraker zero suspension and plus sized wheels: Changed the front to a 29er shod with MM, stuck a (superb) Hunt 27.5 wheel in the back with a Wild 2.8 on it and dwanged the fork out to 160 with a Debonair. Hey presto - feels like my trusty E29. Familiarity rocks. I did shorten the cranks to 165 from 170 and that helps ref pedals strikes.

Sometimes also ride mullet on the E29 and have done for a few years. Pedal strike galore on the climbs, cornering like a demon on the DH. Less rear end wheel flex.

However there are far, far faster riders than me on 27.5 wheels and they are likely to stay for sure.

Perhaps the key is - enjoy what you ride, fettle it to your likes, marginalise the dislikes and go get muddy !

Enjoy.