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I’d say my degree in the field more than “fancies” me.
Put your math where your mouth is. Easy to make statements like that but I want to see the calculations.
 

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I assume fox has done that already and they say no more than 30mm.
surely you’re not advocating his setup as safe.
I suspect that if you analyze the torque from the extra length is it well within design parameters. I suspect that Fox is just being very conservative and has a rather large safety margin.
 

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Armature speller
Unit, Anthem, Stumpy, Secteur
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I assume fox has done that already and they say no more than 30mm.
surely you’re not advocating his setup as safe.
Cannondale says 40mm.
Surly doesn't have a limit.
Z-Pro said:
Spacer stack height limit on the Z-pro is 130mm from frame to top of stem. With standard stems and headsets, that works out to about 90mm of spacers, which is quite a lot. There is no magic to this number, but we need to set a limit somewhere. The issue is not so much safety as it is stiffness. The steerer is not going to break because you put extra spacers above the upper bearing. As you know, the deflection of a cantilevered beam increases exponentially with distance. Adding spacers quickly adds up to a less stiff cockpit.
 

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Did my last race on this frame, it's been quite a reliable prototype of what I wanted over the past 4 years and will go to a tall friend. Yesterday was very muddy and this photo was after I drove home through a thunderstorm. Still picking mud out of my eyes today... but I cleaned a muddy technical climb as good as anyone that had many guys walking, which felt great.

The old Formula R1 brake pads completely wore out, which isn't surprising, but besides sounding like a freight train, they braked just as well. I did get some brake drag on the rear for the last couple of laps. I'm preparing myself to be disappointed with modern brakes like the SRAM Guide Ultimate, since I can't get the R1s in the USA anymore.

The Syncros Hixon bars at 800mm feel great. Colorado trails seem ready for them, but the 770mm Enve M9s I raced prior fit a little better through tighter trails with less stress.

The AXS XX1 shifted amazingly through the nastiness. The lockout managed to stay working, which was a relief. Rocket Rons continue to be a choice mud tire.

1939609


1939608


Sorry the photo of the bike still has me attached ;)

Tallboy 3 CC size XXL sanded and repainted with gold trim, 23.7 pounds.

  • Hand-built wheelset with Berd spokes and Carbonfan 30.5mm internal rims, 1250g.
  • AXS XX1 group including dropper optional.
  • Enve 770mm M9 bars, 35mm stem (about to replace with a 800mm Syncros Hixon)
  • Formula R1 brakes -- going on ten years old!
  • Vittoria Barzo 2.35s with trimmed center knobs or Addix Rocket Ron 2.25 tires depending upon weather, 18/20 psi
  • Fox 34 Stepcast 120mm connected to rear Fox Factory 110mm shock with dual remote lockout.
  • Time ATAC XC pedals, Quarq power meter, WTB Volt carbon saddle on both posts, ESI Chunky foam grips.
  • Replacement of all bolts with gold titanium from BetterBolts.com and lightweight rear and front hex axles.

View attachment 1932814
 

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I assume fox has done that already and they say no more than 30mm.
surely you’re not advocating his setup as safe.
Given that they say nothing about stem length or handlebar width, that 30mm number borders on meaningless. If his steerer is going to shear off where it exists the headset because of those spacers, I'd be awfully worried about my 27.2 seatpost where it inserts into the frame, or where my fork's upper tubes insert into the crown.
 

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Given that they say nothing about stem length or handlebar width, that 30mm number borders on meaningless. If his steerer is going to shear off where it exists the headset because of those spacers, I'd be awfully worried about my 27.2 seatpost where it inserts into the frame, or where my fork's upper tubes insert into the crown.
This stem was popular (and I believe reliable) in the quill stem era. 22.2mm diameter vs. 28.6mm, 160mm sticking out at max insertion, just a wedge holding it at the bottom instead of the much stronger externally clamped design at the stem extension base:

Nitto Technomic Forged Aluminum Stem | Jenson USA
 

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This stem was popular (and I believe reliable) in the quill stem era. 22.2mm diameter vs. 28.6mm, 160mm sticking out at max insertion, just a wedge holding it at the bottom instead of the much stronger externally clamped design at the stem extension base:

Nitto Technomic Forged Aluminum Stem | Jenson USA
In fairness, that isn't a perfect comparison. It'd be harder to break a steel steerer with a quill stem than one for a threadless (aluminum) steerer. The point stands though; given what didn't break in the old days (e.g. 25.4 DH handlebars weren't snapping off all the time), Mikesee's set up should be fine.

Also, it's a custom modern Slingshot. It's kind of a sign saying "Please don't tell me my bike isn't up to safety code".
 

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Given that they say nothing about stem length or handlebar width, that 30mm number borders on meaningless. If his steerer is going to shear off where it exists the headset because of those spacers, I'd be awfully worried about my 27.2 seatpost where it inserts into the frame, or where my fork's upper tubes insert into the crown.
We’ll there you have it, rikmc says its ok so it must be ok. Why heed any manufacturers warnings or recommendations when rikmc knows more than the people who designed it. Why do you suppose forks have max rotor size warnings Einstein? Or why do frames have a max fork travel limit? Don’t worry tho about any of the manufacturer warnings, rikmc says run what ya brung it‘s all safe from him eyeballing it up.
 

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We’ll there you have it, rikmc says its ok so it must be ok. Why heed any manufacturers warnings or recommendations when rikmc knows more than the people who designed it. Why do you suppose forks have max rotor size warnings Einstein? Or why do frames have a max fork travel limit? Don’t worry tho about any of the manufacturer warnings, rikmc says run what ya brung it‘s all safe from him eyeballing it up.
I'm speaking about stem spacers, not rotors or fork lengths. I'm saying their recommendation is incomplete if they don't factor in stem length. Show me how a 40mm stem with 40mm of spacers (not safe) puts more bending force into a steerer than a 120mm stem with 30mm of spacers (safe), with the same load applied at the end.
 

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In fairness, that isn't a perfect comparison. It'd be harder to break a steel steerer with a quill stem than one for a threadless (aluminum) steerer. The point stands though; given what didn't break in the old days (e.g. 25.4 DH handlebars weren't snapping off all the time), Mikesee's set up should be fine.
Actually it's a good comparison. The 7/8" diameter part vertical part of the quill stem is the weak point in the quill stem that I'm comparing to the 1-1/8" aluminum steerer. Both are serving the same purpose of serving as the vertical portion that extends the height of the stem.

I have actually had a quill stem that was broken there. It was on my first non-kid's bike, a ~1970 Steyr Clubman road (now would be called) gravel bike that had been left in my parent's garage by a relative. I claimed it and fixed it up when I was in junior high in the early '80s when it was already a vintage bike, and rode it through high school. One time, after already riding around on it for years, I pulled the stem all the way out, and found that vertical 7/8" part was in two pieces. It must have broken under the previous owner, who just shoved it deeper into the steerer and carried on riding it with just the wedge bolt holding the stem together. The Nitto Technomic was forged and much stronger and better quality than the stem on that bike though.
 

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Actually it's a good comparison. The 7/8" diameter part vertical part of the quill stem is the weak point in the quill stem that I'm comparing to the 1-1/8" aluminum steerer. Both are serving the same purpose of serving as the vertical portion that extends the height of the stem.

I have actually had a quill stem that was broken there. It was on my first non-kid's bike, a ~1970 Steyr Clubman road (now would be called) gravel bike that had been left in my parent's garage by a relative. I claimed it and fixed it up when I was in junior high in the early '80s when it was already a vintage bike, and rode it through high school. One time, after already riding around on it for years, I pulled the stem all the way out, and found that vertical 7/8" part was in two pieces. It must have broken under the previous owner, who just shoved it deeper into the steerer and carried on riding it with just the wedge bolt holding the stem together. The Nitto Technomic was forged and much stronger and better quality than the stem on that bike though.
Fair point, you’re right. I guess it’s a good thing there was a bolt holding the stem together inside the steerer.
 

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Sorry for the gigantic image size. And for the fact that it looks like it was taken with a potato.

This is the most comfortable yet fastest bike/configuration I've thrown together so far. Intense Sniper with 180/Berd/Nextie 30mm internal/30mm deep rims, Hollowgram SRM, XO1 drivetrain, and Magura MT7/8 brakes.

1939771
 

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Sorry for the gigantic image size. And for the fact that it looks like it was taken with a potato.

This is the most comfortable yet fastest bike/configuration I've thrown together so far. Intense Sniper with 180/Berd/Nextie 30mm internal/30mm deep rims, Hollowgram SRM, XO1 drivetrain, and Magura MT7/8 brakes.
So what kind of impact do the berd spokes have on ride quality? Do they help mute the harshness of carbon rims, or is more of a weight thing?
 

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Sorry for the gigantic image size. And for the fact that it looks like it was taken with a potato.

This is the most comfortable yet fastest bike/configuration I've thrown together so far. Intense Sniper with 180/Berd/Nextie 30mm internal/30mm deep rims, Hollowgram SRM, XO1 drivetrain, and Magura MT7/8 brakes.

View attachment 1939771
You must have 1/2 the worlds aluminum supply tied up in that stem!
 
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