EBB or Sliding Dropouts? – Rohloff Custom Frame

I’m looking at getting a custom frame built, rigid 29+ with rohloff. My current frame will be the basis of the geometry with changes to rectify it’s faults. The major one is the rearward facing dropout which makes wheel removal,insertion and disc alignment a right faff on.

I’ve basically got the choice of paragon sliding(or rocker) dropouts where disc alignment isn’t necessary as it’s fixed on the sliding dropout

Or

An eccentric BB where the dropouts are fixed…

EBB seems the neatest solution but I’m concerned about having to adjust saddle to account for BB adjustments for chain tension etc….. Or is it not that noticeable/done infrequently it doesn’t matter?
Sliding dropouts give the same benefits of EBB but without having an effect on saddle height but have the potential to slip or creak as there’s more moving parts potentially..

Anyone had experience of these two systems that can help me decide?

Does a Rohloff work with sliding dropouts? Not saying it doesn’t, just wondering if would be problems with the torque arm.

I’ve had good experience of a Phil Woods EBB on my singlespeed. Have never noticed changes in seat angle / saddle height.

I’d go EBB. The tension adjustment are small, and fore-aft to affect chain length. The height changes are tiny at that part of the rotation.

Also, how often do you really tweak tension? Moving the saddle (if you can notice the difference) a couple of mm now and then isn’t a problem?

I’d not worry about effective seat tube angle changes either… they’re small!

I’m currently waiting for mine (from China….)
I went with sliding drops for mine, mainly to allow chainlength adjustment. I really like the clean look of an EBB, like on my Singular.
This frame will be used mainly for bikepacking / long gravelly days out. Chainstays will be extended out towards 460mm for a nice stable planted feel. It’ll also be used as a SS for knocking around in the woods, in which case the stays can be shortened down towards 440mm.
I’ve actually gone for a 46mm PF BB on this , so I could potentially have an EBB and sliders combined 🙂

Are you going to fit mudguards? Sliding dropouts will be a pain if so

I’d go EBB for ease of taking wheel in and out

Stories of creaking EBBs made me go sliding for my singlespeed (they take a Rohloff I’m told). Possibly lighter?

Do people really worry about a few mm of saddle height? I mean the BB height change will have destroyed the handling already.

Does a Rohloff work with sliding dropouts?

Yeah. Specific dropout to accommodate the small OEM torque arm.

Are you going to fit mudguards?

Yes I am. Current setup is a pain so I’d like this sorted. I have to let the tyre down and/or loosen the guard off a bit. From what I’ve seen of the paragon dropouts though wheel removal is straight down/slightly forward so shouldn’t be a problem.

I’d go EBB. The tension adjustment are small, and fore-aft to affect chain length. The height changes are tiny at that part of the rotation.

Also, how often do you really tweak tension? Moving the saddle (if you can notice the difference) a couple of mm now and then isn’t a problem?

I’d not worry about effective seat tube angle changes either… they’re small!

Good to hear. Thank you.

But

Stories of creaking EBBs made me go sliding for my singlespeed (they take a Rohloff I’m told). Possibly lighter?

Do people really worry about a few mm of saddle height? I mean the BB height change will have destroyed the handling already.

These points makes me want to pick sliding dropouts…

Back and forth, decisions decisions 😂

Custom? Then I’d go for Bushnell EBB and a quality BB shell that’s accurately reamed. Faultless system. Separating all the disc brake and rear axle forces from the chain adjustment mechanism is a good thing to do, partic for a Rohloff with its gearing torque at the axle.

I’ve had both types sliders and EBBs on MTBs and I’m not sure why but I notice the BB axle position change less than the rear axle movement, even though the EBB also changes CS length. Something about bar/HT to rear axle consistency maybe. My MTB BB height varies when I fit winter tyres, varies by less when I adjust the chain tension through maybe a 60 degree rotation range. It’s one of those things that makes me realise I only notice small fit changes for a few miles then I adapt. Maybe I’d notice it more on a road bike with an EBB.

Separating all the disc brake and rear axle forces from the chain adjustment mechanism is a good thing to do, partic for a Rohloff with its gearing torque at the axle

Any evidence that this is relevant, or just an opinion?

I notice the BB axle position change less than the rear axle movement, even though the EBB also changes CS length

Do we need a thread about the subjectivity and unreliability of personal experience and confirmation bias?

I’ve had both. EBB set up correctly, even a cheap one (Charge Plug Grinduro with Chinese crapola) won’t creak. Key is a good clean, good greasing, repeat occasionally if gets especially mucky/dusty.

Adjusted the EBB every once in awhile when tensioning needed, and never noticed any issues with saddle adjustment. Different shoes/socks probably have as much effect, when doing simple “tightening the chain” adjustments.

Sliding dropouts nice, but I find more of a faff – more movable parts to rust/seize, tighter space/packaging constraints if trying to fit disc + Rohloff (I don’t have experience with this) + mud guards.

Both good, neither option well-built will be any problem, but given the choice I’d go EBB.

As the op asked for people’s experience with these two systems not where he could find hard statistically backed evidence of which is the best system I would suggest jameso has given a more helpful reply than cynic Al . Just my opinion mind you , perhaps we need some peer reviewing before it carries any weight mind .

I confess I don’t notice millimetres of change in my chainstays or BB height!

EBB. Plenty good ones about that run silently. Shit ones and oversized BB shells are awful and lead to them all being tarred with the same brush.

Well that’s 6 to 2 in favour of EBB. Who’d of thought this could be a controversial topic 😂.

Paragon sliders every time. I have used them on every frame I built. All my own frames have been built up using a rohloff. PWM sliders also have the benefit of being able to swap the inserts for any axle type you may want to use in the future.

I’ve had both and would take an EBB EVERY time. With an EBB there’s only a single thing to adjust, with sliders, you have to make damned sure that each side changes exactly the same or the disc will rub. Even with Tugnuts, this is a pain. Dependent on the frame, you’ll also need to adjust your brake position each time with a sliding dropout.

Good quality EBB.

Got both. Had quite a few EBBs over the years.

My experience of EBBs is that provided you haven’t allowed a knuckle-dragging neanderthal to adjust the EBB and over tighten it, thereby ovalling the shell and ruining it for ever, then it is the perfect system.

That’s assuming you start with a decent quality frame in the first place.

Can’t comment on EBBs or relative merits of either system, but I have been riding an old Kona with sliding dropouts for the last year (3000km) and been very pleasantly surprised, from a sceptical starting point. No creaking or movement at all. Moving the dropouts all the way back from initially having them forward made a surprising difference to the bike in terms of handling – significantly more planted front end, despite the minor amount of adjustment.

I’d go EBB for ease of taking wheel in and out

The wheel is removed vertically in either case, so there’s no difference.

Had both, both work fine. Personally I’d have a slight preference for sliding dropouts, if they’re Rohloff-specific; but then I’ve not used many types of EBB, and they vary quite a bit.

One marginal difference for a custom build is that the larger shell of an EBB may, I suppose, offer greater scope for strength and stiffness in that area, so if you’re a clydesdale or you’re planning on carrying luggage then maybe it’s a marginally better platform.

Whichever you choose (assuming you choose a good quality implementation of each) you almost certainly won’t end up constantly wishing you’d chosen the other.

Separating all the disc brake and rear axle forces from the chain adjustment mechanism is a good thing to do, partic for a Rohloff with its gearing torque at the axle.

I’d agree with James on this.
I had a custom frame built for a Hoff and the torque it put through sliding dropouts caused constant creaking in the lower gears.
I had it setup with both the custom slider built for Rohloffs and then a Monkeybone.
Monkeybone was a little better but still not great.
A mate also had a custom frame with sliders built for his Hoff and it snapped the chainstay on the brake/torque side…

Sliders are great for singlespeed though as theres no torque kick back like there is with a Rohloff.

I had a Rohloff a few years ago, and based on that experience I’d say EBB for distribution of weight. The Rohloff wheel is a chunkster, and shifts the centre of mass back in the bike; adding more weight at the rear via sliding dropouts (admittedly marginal) wouldn’t be my recommendation.

EBB – but it has to be a Bushnell. Do not skimp on this.

PWM sliders also have the benefit of being able to swap the inserts for any axle type you may want to use in the future.

Good point but I honestly can’t see me ever ditching the rohloff on this bike. It’s perfect for how I will be using it

with sliders, you have to make damned sure that each side changes exactly the same or the disc will rub. Even with Tugnuts, this is a pain.

This is the problem I have now with rear facing dropouts. PMW sliders would solve this though wouldn’t they as the brake is mounted to the slider so move with it. Or is there still a little aligning to do? Johnm18? How did you find this?

One marginal difference for a custom build is that the larger shell of an EBB may, I suppose, offer greater scope for strength and stiffness in that area,

Good point. Probably minor but every little helps. It will be loaded up with kit every now and then.

I’d agree with James on this.
I had a custom frame built for a Hoff and the torque it put through sliding dropouts caused constant creaking in the lower gears

Another good point. Separating drive, torque and braking from the chain length adjustment makes sense to me as well.

EBB for distribution of weight.

Again. Every little helps

EBB – but it has to be a Bushnell

Builder I’m looking at uses these.

@survivor there is no issue with brake alignment as the axle and brake mounts are fixed relative to each other.

Here is the frame I’ve just finished showing the brake, rohloff insert and sliding dropout. The last one had hooded PWM sliders and lasted 11 years and more than 10000 miles of hard mtb riding.

EDIT: With a chainstay/seatstay brace there is no issue from drive torque. The braking forces are far higher than the drive forces and the frame should be built to survive the brake forces anyway.

Yeah. That’s what I assumed originally but the post above had me wondering if there was a bit of play etc… no bother though…

Cool. Have you used a brake rotor as a brace there?

EBB.

Yeah, the brace is a bit of old brake disc.

The only play is standard amount of wiggle you get to adjust all post mount calipers.

There is a lot of love for EBBs. They are good but the main reason I prefer sliding dropouts has been hinted at above. If the EBB is overtightened then it can go oval then it will never be right again. This is what causes most complaints of creaking. If you use a torque wrench every time or are not a ham fisted spanner monkey then they are fine. On the other hand overtighten a slider all you may do is strip the thread and for $12 for a new insert you are back to fully working again.

For me – EBB – more elegant engineering. Taper wedge type tho.

I’ll throw these Salsa Alternator Dropouts into the mix:

https://salsacycles.com/components/category/alternator_dropouts

qwerty
I’ll throw these Salsa Alternator Dropouts into the mix:

I’ve never used them, but they look like an elegant solution and preferable to sliders.

EBB on my BMC.
Rotates with a pin spanner and locks with 4 grub screws. Effortless.

Aren’t grub screws known to fail over time, by making indents?

I don’t know that. I do leave tensioning a bit longer than I should so I get more movement. I also tension the belt at the lower end of the range when new and high end when older.
Plus flipping the BB case when I change the actual BB puts the wear on a different part of the case.
We shall see, it’s only 8 years so no idea of longevity.
I must try and source a spare.

I noticed Phil Wood doesn’t make the old grub screw ebb any more (like Singular used to use).

I’ve never had luck with Bushnell copies and find the gaps in expanding cams just ingest mud by capillary action so they need stripping / cleaning before adjustment if you ride in gritty wet places.

Cannondale ramp-wedge type was pretty reliable on the tandem and didn’t leave gaps for muck.

If you do go ebb, then design the chainstay length around your anticipated ratio – Bushnells don’t have a huge range of adjustment and with chain stretch some ratios won’t work without a half link.

I seem to remember Rohloffs are also designed to run with a large chainring, so a lot of reduction (and hence torque reaction) has to go on in the hub and out through the dropout.

I’ve always found the Cannondale benefitted from being taken out and lubed on a regular basis.

Rohloff + Rideworks EBB here. About to upgrade to Bushnell.

Wouldn’t fancy sliding dropouts tbh.

Any evidence that this is relevant, or just an opinion?

The highest gear torque (low gear ratios) is in the other direction to the braking force which is unusual for a dropout. From what I’ve read an average rider climbing in lowest gear on a Rohloff can put more torque into the frame than a disc brake. Whether accurate or not we could work on it being close to equal at times, a fair bit of back+forth force. It’s a bit like a square taper crank, if you ride right foot forward then landings and impacts torque the left crank opposite to the pedal load and that’s always the one that works loose or gets damaged easiest. I reckon it’s how one set of sliders I saw damaged worked a bit loose, or the loose bolt let it to-fro and cause damage to the Al insert. Another set wasn’t on a Rohloff bike but the dropout’s inset part that sits in the harder frame slot deformed under some hard, loaded riding presumably after the screw loosened. I’ll stick to my opinion that a good EBB (clamp shell or Bushnell) and a fixed dropout is preferable, not to say it’s the only solution.

I notice the BB axle position change less than the rear axle movement, even though the EBB also changes CS length

Do we need a thread about the subjectivity and unreliability of personal experience and confirmation bias?

Probably not but I find it interesting stuff anyway. You can read my post as just an opinion fwiw, I think that was fairly clear from what I said.

I’ve had no issues at all with a Rohloff and EBB with set screws in the 13 years or so I’ve owned it. I’ve occasionally altered the saddle when adjusting the chain tension but it’s a very minor thing. I tend to wait till the chain falls off to adjust it rather than by looking at it and thinking it needs doing. I like it as much as anything because it’s the neatest looking option.

I’ve had both types due to having frames replaced under warranty, twice! First 2 frames were Van Nicholas Redwood 29ers which were a specific model year that came with horizontal track dropouts which, with a bit of torque arm bodging, allowed a Rohloff to work no problem. They replaced the second one which cracked around the headtube/downtube weld with a Zion Rohloff specific frame with Bushnell EBB which needs liberal use of loctite to stop the wedges loosening but otherwise works well. The only other issue I’ve had is the positioning of the double gear cable guides which cause issues with fitting a bar bag when bikepacking. Overall, I’d say EBB offers the least amount of faff and I’ve not experienced any creaking issues.

“Track dropouts” or track ends are not the same as sliding dropouts.