Dumb question re: bottle cage spacers

[henrypretz]

New (to me) bike day! Purchased a demo Niner RLT steel to take the place of my RLT Alloy. I’d been sniffing around for one of them in my size and this popped up.
Anyway, the bottle cage bolts came with these spacers on them and I’m wondering if you all can help me figure out if they need to stay or would I be ok leaving them off? (I told you it was a dumb question)
I wondered if they had anything to do with derailleur clearance, but the cage clears even when they’re not installed.
My other Niner did not have them when I got it.
Thank you for your indulgence.
Henry

https://uploads.tapatalk-cdn.com/20190914/710f01b1a93b65fb85b2391ed3cbf6fc.jpghttps://uploads.tapatalk-cdn.com/20190914/c15c3871aa282f84d8a84e18770c9916.jpg

[Dino Suegiù]

They look like original kit. Why not just use them?

https://content.competitivecyclist.com/images/items/900/NNR/NNR0099/ORA_D1.jpg

https://content.competitivecyclist.com/images/items/900/NNR/NNR0099/ORA_D6.jpg

[Louis]

I would say that if they really don't serve a practical purpose (e.g. providing clearance for the F-der clamp) then don't use them. Mostly because you'll be reducing the size of the overhung moments, and that will buy you a small reduction in the stresses in the seat tube.

[Dino Suegiù]

I would say that if they really don't serve a practical purpose (e.g. providing clearance for the F-der clamp) then don't use them. Mostly because you'll be reducing the size of the overhung moments, and that will buy you a small reduction in the stresses in the seat tube.

With all due respect, are you being serious?
Niner supply them with the frame, so one would guess that they have covered the "overhung moments" issue.
If the very minimal extra offset of that mini-spacer (which actually looks well-designed) is enough to so exacerbate "the stresses in the seat tube", then that frame is unsafe.
All kinds of spacers (frame pump brackets, cage clearance, King Kargo cages, etc.) have been used with no issue for years.

Come on, be, in fact, practical.

[tony_mm]

Which purpose do these spacers have?

[Louis]

With all due respect, are you being serious?
Niner supply them with the frame, so one would guess that they have covered the "overhung moments" issue.

Yes, I am serious. I didn't say it was a huge factor, nor that it save the OP from failure. The moment is linearly proportional to distance from the CG to the support point, so removing the spacer results in a non-trivial reduction in that distance. Certainly more than just one or two percent.

Come on, be, in fact, practical.

My point exactly. If they don't serve a purpose they are not practical, and can be removed.

If the OP wants to keep them on, then leave them. He asked for opinions and I gave mine, along with a reason.

Why keep them if they aren't needed?

At least I didn't say that taking them off would make the bike lighter and allow the OP to ride faster...

[Blue Jays]

The tiny bit of stand-off from the frame might make it easier to clean with a soft towel and soapy water.

[fignon's barber]

My guess is that they put the spacers there to keep the wet bottle a bit further from the alloy, and also give more space for the area to dry. Also makes it easier to clean.

[oldpotatoe]

To keep the bike at the UCI minimum weight, of course..:)

Probably keep the cage off the frame/paint..might relieve the stress a bit if the bottle 'brazeons' are riv-nuts..

[Jeff N.]

I've used the little spinner nuts that come with most inner tubes for cage spacers, but only if there's FD clamp clearance issues. If YOU don't have those issues, no need for them. You can use them or not...no biggie either way. I take Visa, Mastercard, AMEX, well-wrapped cash.

[Peter P.]

Sometimes spacers are needed on the seat tube, if the waterbottle cage design will interfere with the front derailleur clamp.

It depends on the design of the cage.

On the downtube, they could be useful IF the design of the bottle cage causes the body of the cage to contact the downtube before the bolt mounts do. The greater the contact area, the more potential for sweat to collect (on steel frames) and rust to form. The spacers would provide offset, so only the mounting points contact the downtube.

On the underside of the downtube on that frame in the photos, it looks like it's possible for a bottle cage to touch the hydraulic cable guide if there's insufficient standoff. The spacers would come in handy here.

Personally, I'd be really concerned about aerodynamic drag. ;)

[Dino Suegiù]

Sometimes spacers are...[all practical info]...handy here.

Personally, I'd be really concerned about aerodynamic drag. ;)

Yes, of course that would be an additional major worry, as it would probably calculate out to a factor +/- at least somewhat close to the aerodynamic drag of tread nubs on brand-new GP4000s aka "non-trivial trivial aerodynamic drag".

However, to be truly practical and also completely fair and balanced regarding the multitude of factors surrounding this decision, it would be really terrific if someone could precisely calculate the:
A) Positive Effects: just leave the damned spacers on because they're already there + are "sport-beer compatible" + less stress + fd, cable, accessory mount, etc clearance + frame finish protection + cleaning convenience + looks kind of cool + landfill waste reduction
versus
B) Negative Effects: really trivial but therefore technically non-trivial overhung moments/stresses in the seat tube + increased aerodynamic drag + as-yet-unknown/undetermined factors to also worry excessively about.

How do the pros/con balance out?
- Anxiously Awaiting Answers.

If the numbers are overwhelmingly negative (majorly increasing both tube stresses and aerodynamic drag, mainly), then some people could maybe make some big bucks suing Niner, Problem Solvers, Rivendell, Amazon, Ace Hardware, and all the other entities that produce and/or sell these terrible stand-off/space-out spacer things.

Or, just wait for the Silca et al carbon-fiber aero versions to hit the market.

;)

[henrypretz]

OP here - I did all of those calculations detailed here. The results, which were quite complicated, led me to leave the spacers in.
Another problem solved by the Paceline crew!
You all are the best :banana:

Yes, of course that would be an additional major worry, as it would probably calculate out to a factor +/- at least somewhat close to the aerodynamic drag of tread nubs on brand-new GP4000s aka "non-trivial trivial aerodynamic drag".

However, to be truly practical and also completely fair and balanced regarding the multitude of factors surrounding this decision, it would be really terrific if someone could precisely calculate the:
A) Positive Effects: just leave the damned spacers on because they're already there + are "sport-beer compatible" + less stress + fd, cable, accessory mount, etc clearance + frame finish protection + cleaning convenience + looks kind of cool + landfill waste reduction
versus
B) Negative Effects: really trivial but therefore technically non-trivial overhung moments/stresses in the seat tube + increased aerodynamic drag + as-yet-unknown/undetermined factors to also worry excessively about.

How do the pros/con balance out?
- Anxiously Awaiting Answers.

If the numbers are overwhelmingly negative (majorly increasing both tube stresses and aerodynamic drag, mainly), then some people could maybe make some big bucks suing Niner, Problem Solvers, Rivendell, Amazon, Ace Hardware, and all the other entities that produce and/or sell these terrible stand-off/space-out spacer things.

Or, just wait for the Silca et al carbon-fiber aero versions to hit the market.

;)

[Peter P.]

OP here - I did all of those calculations detailed here. The results, which were quite complicated...

I wanna see your paperwork; maybe publish it as a doctoral thesis. :banana:

[AngryScientist]

Probably intended to facilitate cleaning. Especially on an off-road bike, dirt and grime can accumulate behind the cages and a little more stand off distance let’s you get a rag or detailing brush back there easier. That’s my guess.

[duff_duffy]

Saw a poorly designed cage “pressed” into carbon frame once...owner certainly wished there was spacer! The cage design was just too low and when tightened down just hit the frame enough to press onto frame leaving slight indentation.

[cderalow]

Surprised no one is bringing up the concept of isolating a potentially alloy cage from the steel frame to help prevent galvanic corrosion which would either ruin the frame boss, or fuse the bolt into the frame.


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[unterhausen]

Maybe ask the manufacturer?

I probably would leave them off. I don't see the value. But maybe I'm missing something

[p nut]

I have a frame where the front D mounts right in between the bolts. Spacers needed there.

But that doesn’t seem to be the problem here. Take them off. Besides serving no purpose, they look silly.

[PacNW2Ford]

Surprised no one is bringing up the concept of isolating a potentially alloy cage from the steel frame to help prevent galvanic corrosion which would either ruin the frame boss, or fuse the bolt into the frame.


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Unless of course the spacers themselves are aluminum...

[tony_mm]

I would really be interested on what the manufacturer says about these spacers!

[cmbicycles]

Those spacers act like the swirl lip generator on Reynolds wheels, decreasing air turbulence around the water bottle cages. With the massively decreased aero resistance, I wouldn't take them off unless you really want to work a lot harder when pedaling. Leave them on and it's basically like you are riding a e-bike, take them off and... well, you've been warned.

;)

[tony_mm]

Those spacers act like the swirl lip generator on Reynolds wheels, decreasing air turbulence around the water bottle cages. With the massively decreased aero resistance, I wouldn't take them off unless you really want to work a lot harder when pedaling. Leave them on and it's basically like you are riding a e-bike, take them off and... well, you've been warned.

;)



That’s a good one! [emoji23][emoji1787]

[dave thompson]

On aircraft they are known as vortex generators.

[.RJ]

Which purpose do these spacers have?

If I had to guess its dropper post clearance (bolts poke through seat tube) so they serve purpose of niner doing ****ty QC on frames and requiring them post-build to fix problems. If there was FD or dropper post or otherwise clearance problems they should have welded standoffs to the frame as part of the manufacturing.

But hey, even if you have to chase and face every f'ing surface on the bike they tell you that you're dumb and you should be paying your LBS to be doing this for you when they build your bike. The level of work required on this brand's frames before you can build them up is absurd.

I used to be a niner fan. Too bad they stopped innovating 10 years ago.