"E-bike" rated Forks - hooey?

[Jeffsy29]

Everyone laughs about "E-bike" rated lube, seats, grips, valve-caps and tire levers.....who doesn't enjoy a good chuckle at eMTB Marketing Gone Wild??

I've been conversing with a *very* helpful and patient Tech Support rep from Fox, but no matter what fork I seem to discuss, they seem to have a hard-and-fast response of:

"For your bike/rider configuration...we highly recommend the E-tuned fork"
OR
"I would caution you as the Z1 isn't rated for ebikes"
OR
"We don't have a coil e bike fork at this time".​

From my experience, and from what I've read, there seems to be very minor tuning differences limited to either damping or volume reducers between 'standard' and 'E-rated' Fox forks. And in some cases, not in the direction that I'd prefer (I'd like fewer spacers and less compression damping please).

For example, the Fox 36E+ on my stock Decoy29 is essentially a 34 inside so that the tube walls can run thicker. Sure, this helps stiffness a little, but so would a thinner-walled 38mm tube! 36E+ also comes with 4 spacers vs 2 spacers in the standard 36. What on the 36E+ is any better than it's standard brother Fox 36? Nothing that I know of, unless you want an extra 2 spacers. Upgrade path is much pretty dead-end on 36E+.

I was flat-out advised against the Bomber Z1 Coil by Fox since it's "not E-rated", though the Z1 chassis is probably robust enough to deal with my portly 270-275 lb. kitted-gear rider weight. (spring rate is another matter, however).

When I asked Fox Tech Support about Fox 38 vs. 38E+ differences, they said "talk to your local bike shop". Thanks Fox...... I've read elsewhere it's just slight damping differences. But I find the 36E+ HSC and LSC too stiff even in wide-open position. I'm inclined to go for the Standard 38 for some adjustment head-room so I can actually tighten HSC and LSC down somewhere in the middle as proposed in the Fox tuning guide. I have a standard 38 on back-order at the moment - against Fox's advice. I guess I can always jam a Smashpot coil in there if I need more suppleness.

Is there any real benefit to an E-rated fork?, or is it likely just more hooey than anything? I don't see anyone taking the time/money to reinforce their crowns/steerer tubes on E-bike forks like Fox has on the 38 oval steerer. That would be something tangible that one could claim as 'stronger' than the standard version. The rest of the E-rating on forks seems a bit dubious or at least, less important as a bike-stressor than rider weight and riding style. The +15-20 lbs of an E-bike pales in comparison to +100 lbs of variation amongst bike riders.

 

[H.E.]

Think they going to far with the forks, i also would not buy the ebike Fork - makes absolutely no sense to me.
Its kind of like with the brakes you need to break your total weight anyway. (Must say i like that move to more 4Piston breaks
and big Rotors generally)
I've a ZEB R that came with the bike, the trailhead website from Rock Shox gives you settings for youre weight, i found out
later (when you go over the models and not the serial number) that they add +10psi on all ebikes. Run it at 50psi right now so this would
be 20% more pressure and makes that thing really stiff.

 

[Konanige]

Cant comment on the 'E' forks as I ride an SL so can run standard 36, but as an aside being a 240lbs biffer myself I found I couldnt get a good mix of small bump sensitivity and midstroke support from an air spring, so I went with the Smashpot coil conversion. Absolutely transformed the fork, magic carpet, plenty of support in the mid stroke and externally adjustable end stroke ramp up, perfect!

 

[Smittylube]

I went with the Zeb ultimate on my Rail 7 but IMO the main takeaway is you are happy with the ride and feel in the end. Everyone has their own opinion of what good is and there are plenty of good or great options out there. If it keeps you riding or gets you out on the bike then it is 'the right one' for you.

 

[Gary]

Forget Ebike rated
You need 270lb+ rider rated

 

[Jeffsy29]

Forget Ebike rated
You need 270lb+ rider rated

Yuppers

 

[Tim1023]

Forget Ebike rated
You need 270lb+ rider rated

Perhaps they think that "porker-rated" wouldn't sell so well.

Not everyone can cope with "Fat Lad At the Back" humour

 

[Beekeeper]

We have forks which have a sticker on them saying ebike specific. They also have another sticker on them saying no downhill / jumping / or hard riding LOL. Says it all really

 

[Gary]

Perhaps they think that "porker-rated" wouldn't sell so well.

Not everyone can cope with "Fat Lad At the Back" humour

I'm not sure who you even think "they" is bro.

And I'm not sure what's so humerous about being fat either. All cycling is vastly improved with a lean fit efficient body. Even E bicycling.

 

[RustyMTB]

Running a set of old non boost Yaris on a 25kg ebike. Haven't snapped anything yet.

 

[Tim1023]

I'm not sure who you even think "they" is bro.

And I'm not sure what's so humerous about being fat either. All cycling is vastly improved with a lean fit efficient body. Even E bicycling.

"They" = marketing people at fork manufacturers and others in the supply chain. I've worked in marketing.

I wasn't saying weight is humorous as in "look at the funny fat guy". I'm a bit of a porker myself at 114kg and 189cm tall, so I have problems getting decent clothing that fits. However, a bit of self-deprication is permissible, I believe. For me, wearing something from Fat Lad At the Back is also a bit of a "Fuck you" to the arrogant whippets, even if they're too dumb to get it.
Err.. bro.

...still working on that lean body...

 

[Gary]

I don't think I do "get it"

To assume all fit, lean, healthy people who look after themselves and pay attention to what they eat are arrogant just screams of insecurity.
I'm really not sure an overweight guy wearing a badly fitting top with a "funny" slogan on it is even going to register with them. Nevermind be taken as a "fuck you"

 

[Mikerb]

As far as I can see the main difference between stock forks ( and shocks) and supposed E rated forks and shocks is factory tune uprate to hard for compression and maybe also rebound.
I have a 2019 Levo Comp. I changed the fork to a Lyric Ultimate...standard medium factory tune; and the shock to a Fox DPS that I bought unused taken off a Levo SL..also medium factory tune. The ride both fron tand back is plush with really good progression and 100% better than the original RS Deluxe RT/ RS Revelation combo.............in fact transformational!!
My Whyte E180RS has Fox 38 factory 38/Fox factory Float X2 combo and in line with Whyte's suspension set up philosophy the factory tune on both is medium throughout. Fantastic set up.

 

[Tim1023]

I don't think I do "get it"

To assume all fit, lean, healthy people who look after themselves and pay attention to what they eat are arrogant just screams of insecurity.
I'm really not sure an overweight guy wearing a badly fitting top with a "funny" slogan on it is even going to register with them. Nevermind be taken as a "fuck you"

...okay!

 

[ebikerider]

I don't think I do "get it"

To assume all fit, lean, healthy people who look after themselves and pay attention to what they eat are arrogant just screams of insecurity.
I'm really not sure an overweight guy wearing a badly fitting top with a "funny" slogan on it is even going to register with them. Nevermind be taken as a "fuck you"

There is so much you don't "get"

And...."fuck you"

 

[Gary]

You wish big boy

 

[SGS]

I love my non ebike 38's. But the main reason why I bought them is because I wanted 44mm offset in a shiny orange fork, and you can't get that configuration in ebike specification

 

[gbrecke]

Think they going to far with the forks, i also would not buy the ebike Fork - makes absolutely no sense to me.
Its kind of like with the brakes you need to break your total weight anyway. (Must say i like that move to more 4Piston breaks
and big Rotors generally)
I've a ZEB R that came with the bike, the trailhead website from Rock Shox gives you settings for youre weight, i found out
later (when you go over the models and not the serial number) that they add +10psi on all ebikes. Run it at 50psi right now so this would
be 20% more pressure and makes that thing really stiff.

When you give the Marketing Department the lead, you should expect them to market BS, because that's what a lot of people want to buy.

 

[rYz11]

Cant comment on the 'E' forks as I ride an SL so can run standard 36, but as an aside being a 240lbs biffer myself I found I couldnt get a good mix of small bump sensitivity and midstroke support from an air spring, so I went with the Smashpot coil conversion. Absolutely transformed the fork, magic carpet, plenty of support in the mid stroke and externally adjustable end stroke ramp up, perfect!

What spring did you get with your Smashpot? I'm the same weight as you and considering one for my Fox 36.

 

[Konanige]

What spring did you get with your Smashpot? I'm the same weight as you and considering one for my Fox 36.

Went with recommended spring first, but found it too stiff for my liking so went down to a 50lbs that seems about right.

 

[kbass24emtp]

The Fox EMTB 38 fork has a softer compression tune compared to the normal 38. I emailed Fox and that's what the told me.

 

[Jeffsy29]

The Fox EMTB 38 fork has a softer compression tune compared to the normal 38. I emailed Fox and that's what the told me.

Really?? That seems so counterintuitive that they'd choose softer on a heavier chassis that's presumably going faster (on avg.).

Was that the Fox tech support folks? They wouldn't tell me details. If so, I'd choose the softer E+ version every time - you can always add compression it seems on Fox, but I find I run them largely wide open to get suppleness back in.

 

[SGS]

Really?? That seems so counterintuitive that they'd choose softer on a heavier chassis that's presumably going faster (on avg.).

Was that the Fox tech support folks? They wouldn't tell me details. If so, I'd choose the softer E+ version every time - you can always add compression it seems on Fox, but I find I run them largely wide open to get suppleness back in.

Fox's reasoning is that because you are likely to be seated more on an ebike, therefore the softer tune. I have my non-ebike fork set at 5 clicks in from wide open on LSC and 2 from open on HSC and it's beautiful

 

[cguy]

Really?? That seems so counterintuitive that they'd choose softer on a heavier chassis that's presumably going faster (on avg.).

Was that the Fox tech support folks? They wouldn't tell me details. If so, I'd choose the softer E+ version every time - you can always add compression it seems on Fox, but I find I run them largely wide open to get suppleness back in.

If you look at the shim stacks for the 38 vs the 38e available on the fox parts listing pages you can see that indeed the tunes for most of the dampers are softer than the non ebike version. Excepting the Grip 2 damper which shares the same tune, but presumably they'd just expect you to adjust the dials a bit differently on the Grip 2.

I don't think some of the forks having non-hollow crowns and thicker stanchions should be necessarily dismissed out of hand, especially for bigger riders. I bet real stiffness gains are made with those changes. I don't think the 38 has any actual changes there though? But the 36E should be reasonably stiffer than the 36, I'm guessing moving from a 36E to 38 in terms of stiffness wouldn't be that significant change because of that. I guess we'd need more reliable 36E reviews or testing regarding the stiffness of the E CSUs.

 

[kbass24emtp]

Really?? That seems so counterintuitive that they'd choose softer on a heavier chassis that's presumably going faster (on avg.).

Was that the Fox tech support folks? They wouldn't tell me details. If so, I'd choose the softer E+ version every time - you can always add compression it seems on Fox, but I find I run them largely wide open to get suppleness back in.

Yes that was for Fox Support. Like SGS said it’s softer because of being in the seat more.

 

[Tedgar]

The Fox EMTB 38 fork has a softer compression tune compared to the normal 38. I emailed Fox and that's what the told me.

I have em and I agree.

 

[robbydobs]

If anyone's looking into this in the future, Fox actually have a good Q&A on their website. I found this thread after looking for some new forks myself, so thought I'd post up in case it's useful...

Short version - standard Fox 36 fine on an ebike up to total weight of 140kg.

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What is the difference between e-tuned and e-optimized?
E-tuned focuses on the tuning of the fork’s damper, while e-optimization focuses on alterations to the fork’s chassis.

Why isn’t there an E-optimized 38?
The 38 exceeds our stiffness benchmark for eMTB applications, therefore it only requires an eMTB-specific tune.

Can I purchase an E-Live Valve system in aftermarket?
No. We do not offer E-Live Valve system in aftermarket, only on OEM complete bikes.

Do e-optimized 36’s use the same air spring as standard 36’s?
No, the piston diameter is smaller to account for thicker stanchion walls.

Can I run a standard 36 or 38 fork on my e-bike?
You can run a standard 36 fork on a Class 1 eMTB with a max system weight of 140Kg. You can run a 38 fork on a Class 1 or Class 3 eMTB with a max system weight of 169Kg.

Do you sell eMTB-specific rear shocks?
No. Rear shocks on ebikes are tuned to the bikes, if you want to explore custom tuning options, please explore tuning options with our FOX Factory tuning program.

Are Transfer seatposts eMTB rated?
Transfer’s are compatible with Class 1 and Class 3 eMTBs with a system weight up to 169Kg.

Is the FOX 40 ebike rated?
It’s compatible with Class 1 eMTB’s with a max system weight of 140Kg

Are Kabolt X axle’s compatible with EMTB forks (are they strong enough and rated for eMTB)?
Yes. The Kabolt X axle has been tested up Class 3 and 169Kg system weight limit.

Why don’t you make different lowers for e-optimized 36’s?
When lower legs are properly engineered and designed, they pass all standard MTB and E-bike+ lab and field test requirements. In the interest of common parts and quick service, it is advantageous to the customer to have a common lower leg for both standard MTB and E-bike+ fork applications.

What is the weight difference between a E-optimized 36 and a standard 36?
E-optimized 36 is 227.5g [0.50 lbf] heavier than the standard 36.

 

[MO1]

I have the ebike Fox Factory 36 with grip 2 on my Husqvarna MC7 150mm and it is great. Although my regular bike had a rockshox 35 gold rl and ive only been biking 8 months