MTB Tech Rumors and Innovation

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dolface
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5/20/2025 7:25am
Yes many factors with axle thickness can play a roll. The clamps make a giant change as well. The dorado going from 1 bolt upper to...

Yes many factors with axle thickness can play a roll. The clamps make a giant change as well. The dorado going from 1 bolt upper to 2 bolt upper added a lot of torsional rigidity.

IMG 6707.jpeg?VersionId=RGetYimUZ KtVppBk7aklcBHpl.0IMG 6708
cstone28 wrote:

Who makes this 20mm to 15mm adapter and is it Boxxer specific or do they make them for other forks? 

1
cstone28
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5/20/2025 7:40am
cstone28 wrote:

Who makes this 20mm to 15mm adapter and is it Boxxer specific or do they make them for other forks? 

az2au wrote:
Freaky Nuts also makes them.  I'm considering put a Fox 40 on my A.170 for park use this season and ordered one of these for the...

Freaky Nuts also makes them.  I'm considering put a Fox 40 on my A.170 for park use this season and ordered one of these for the conversion if I go that way.  The materials seem to be of high quality.  Compatible with Boxxer, Fox 40 and Rux38.

https://www.freakynuts.com

Thanks everyone. Looks like Freaky Nuts doesn't do Ohlins so that doesn't work for me but still looks like a great solution.

An A.170 with a DC fork is very nice.

IMG 8814
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Digit Bikes
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5/20/2025 9:08am

Most 15mm axles are hollow aluminum. The easiest solutions to making them stiffer is to not hollow them out, and/or to make them from steel or titanium. I've not done the calculations (@Primoz, didn't you do that?), but I imagine it could be as stiff as thin walled aluminum 20mm axles.

If you look at huck to flat videos it seems that the worst of the flex is at or around the crown. The most productive solution for single crown forks might be to return to 100mm OLD - a 10% narrower CSU would be 10% stiffer.

10
5/20/2025 10:07am

Something new on the way from EXT?

IMG 2486 0.jpeg?VersionId=oxA89HS2VC

P.S I have a 190mm air spring for a fox 40 available for anyone looking to lower a set for their park / enduro setups 🙂 drop me a message if you’re interested

6
1
Primoz
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SI
5/20/2025 11:58am
Most 15mm axles are hollow aluminum. The easiest solutions to making them stiffer is to not hollow them out, and/or to make them from steel or...

Most 15mm axles are hollow aluminum. The easiest solutions to making them stiffer is to not hollow them out, and/or to make them from steel or titanium. I've not done the calculations (@Primoz, didn't you do that?), but I imagine it could be as stiff as thin walled aluminum 20mm axles.

If you look at huck to flat videos it seems that the worst of the flex is at or around the crown. The most productive solution for single crown forks might be to return to 100mm OLD - a 10% narrower CSU would be 10% stiffer.

Yeah, it was included (had to even check it as I didn't remember).

https://www.vitalmtb.com/forums/The-Hub,2/Are-Upside-Down-forks-really-flexy,11099?page=0

15 and 20 mm axles with thicknesses of 1, 2, 2,5, 3 and 4 mm were compared. Thickness and diameter have an effect on torsion with USD forks, but still somewhat minor (roughly 10 % going from 10 to 20 mm with the same thickness).

While clamping width was tested I think the main difference was the stiffness of the 'dropout' as the whole assembly was bonded together. Ideally a system with realistic clearances would be simulated (and tested) to show real world differences as it will not be the same, even with pinchbolts clamping down on the axle.

FWIW, old 20 mm Maxles were interesting as they had expanding cones on both sides wedging themselves into the dropouts of the fork AND a step in the axle pressing the hub towards the NDS dropout (aligning the rotor every time) and possibly allowing some float in the dropout for the lower to run smoother. Come to think of it, do modern forks have more clearance in the bushings to offset this issue? @Dave_Camp any insights on this one?

2
sharpy212
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Location
GB
5/20/2025 12:20pm

Anyone know what brake lever Troy is using on his Mavens? 

IMG 7458.png?VersionId=Bjmp9tYTcojtTC80NrQ5
4
Digit Bikes
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180
Joined
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Location
Irvine, CA US
5/20/2025 12:24pm Edited Date/Time 5/21/2025 8:11am
Most 15mm axles are hollow aluminum. The easiest solutions to making them stiffer is to not hollow them out, and/or to make them from steel or...

Most 15mm axles are hollow aluminum. The easiest solutions to making them stiffer is to not hollow them out, and/or to make them from steel or titanium. I've not done the calculations (@Primoz, didn't you do that?), but I imagine it could be as stiff as thin walled aluminum 20mm axles.

If you look at huck to flat videos it seems that the worst of the flex is at or around the crown. The most productive solution for single crown forks might be to return to 100mm OLD - a 10% narrower CSU would be 10% stiffer.

Primoz wrote:
Yeah, it was included (had to even check it as I didn't remember).https://www.vitalmtb.com/forums/The-Hub,2/Are-Upside-Down-forks-really-flexy,11099?page=015 and 20 mm axles with thicknesses of 1, 2, 2,5, 3...

Yeah, it was included (had to even check it as I didn't remember).

https://www.vitalmtb.com/forums/The-Hub,2/Are-Upside-Down-forks-really-flexy,11099?page=0

15 and 20 mm axles with thicknesses of 1, 2, 2,5, 3 and 4 mm were compared. Thickness and diameter have an effect on torsion with USD forks, but still somewhat minor (roughly 10 % going from 10 to 20 mm with the same thickness).

While clamping width was tested I think the main difference was the stiffness of the 'dropout' as the whole assembly was bonded together. Ideally a system with realistic clearances would be simulated (and tested) to show real world differences as it will not be the same, even with pinchbolts clamping down on the axle.

FWIW, old 20 mm Maxles were interesting as they had expanding cones on both sides wedging themselves into the dropouts of the fork AND a step in the axle pressing the hub towards the NDS dropout (aligning the rotor every time) and possibly allowing some float in the dropout for the lower to run smoother. Come to think of it, do modern forks have more clearance in the bushings to offset this issue? @Dave_Camp any insights on this one?

I forgot to mention that 100mm OLD would also be 10% stiffer for the axle and for the arch.

I remember various fork and component engineers shaking their heads in disbelief when the industry decided to settle on 15x110 rather than 15x100. Spoke triangulation has always been better for front wheels than rear, wheel manufacturers seem to chase front wheel compliance. 

4
AndehM
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El Granada, CA US
5/20/2025 12:26pm
sharpy212 wrote:
Anyone know what brake lever Troy is using on his Mavens? 

Anyone know what brake lever Troy is using on his Mavens? 

IMG 7458.png?VersionId=Bjmp9tYTcojtTC80NrQ5

Looks like Freedom Coast.  In another shot I saw the little flag etching near the pivot.

7
ebruner
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Location
Tustin, CA US
5/20/2025 12:40pm
sharpy212 wrote:
Anyone know what brake lever Troy is using on his Mavens? 

Anyone know what brake lever Troy is using on his Mavens? 

IMG 7458.png?VersionId=Bjmp9tYTcojtTC80NrQ5
AndehM wrote:

Looks like Freedom Coast.  In another shot I saw the little flag etching near the pivot.

That's correct, those are freedom coast.  I have those on one bike and a set of oak components on another. I prefer the oak components.  

6
AndehM
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5/20/2025 12:43pm
ebruner wrote:

That's correct, those are freedom coast.  I have those on one bike and a set of oak components on another. I prefer the oak components.  

You put either of them on Mavens?  I know the PB review of both on TRPs preferred Oaks as well.  I was curious if they change the Maven feel at all other than adding texture.  I don't have any issue with the stock Maven levers, but the Oaks look pretty.

1
FaahkEet
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Falls Church, VA US
5/20/2025 12:57pm
ebruner wrote:

That's correct, those are freedom coast.  I have those on one bike and a set of oak components on another. I prefer the oak components.  

How do the Oaks compare to the Freedoms in shape? Are the Oaks any closer to the bars, or basically the same? Have the Freedoms but would be interested in Oaks if they sit closer to the bars.

1
swadd1er
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GB
5/20/2025 1:05pm

I wasn't too sure where to post this so feel free to delete or move accordingly if it's in the wrong thread. Troy Brosnan's mechanic seems to be double taping the rim. Once with the Dt-Swiss rim tape and then a layer of Gorilla Tape over the top?

What could the reasons be behind this? It looks like the DT tape is going from edge to edge so the Gorilla wouldn't be offering any additional adhesive. Is it a tape thickness thing? Never seen anyone double tape like that before. Screenshot 2025-05-20 210427.png?VersionId=h096LVSEtJF4L03L4dmrzD6Ueap4Slg

11
5/20/2025 1:17pm
swadd1er wrote:
I wasn't too sure where to post this so feel free to delete or move accordingly if it's in the wrong thread. Troy Brosnan's mechanic seems...

I wasn't too sure where to post this so feel free to delete or move accordingly if it's in the wrong thread. Troy Brosnan's mechanic seems to be double taping the rim. Once with the Dt-Swiss rim tape and then a layer of Gorilla Tape over the top?

What could the reasons be behind this? It looks like the DT tape is going from edge to edge so the Gorilla wouldn't be offering any additional adhesive. Is it a tape thickness thing? Never seen anyone double tape like that before. Screenshot 2025-05-20 210427.png?VersionId=h096LVSEtJF4L03L4dmrzD6Ueap4Slg

One reason might be to prevent flats. I've only had 2 flats in the past year and a half, but both were from breaking a spoke, which then pushed back through the hole in the DTSwiss rim and punctured the rim tape. Regular rim tape (stans, mucoff, etc) isn't good against spoke impacts, but it doesn't leave residue when you peel it off like Gorilla tape. If combined, you get no residue, but also better resistance against spoke punctures. 

19
MikeyE
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POWAY, CA US
5/20/2025 1:18pm
swadd1er wrote:
I wasn't too sure where to post this so feel free to delete or move accordingly if it's in the wrong thread. Troy Brosnan's mechanic seems...

I wasn't too sure where to post this so feel free to delete or move accordingly if it's in the wrong thread. Troy Brosnan's mechanic seems to be double taping the rim. Once with the Dt-Swiss rim tape and then a layer of Gorilla Tape over the top?

What could the reasons be behind this? It looks like the DT tape is going from edge to edge so the Gorilla wouldn't be offering any additional adhesive. Is it a tape thickness thing? Never seen anyone double tape like that before. Screenshot 2025-05-20 210427.png?VersionId=h096LVSEtJF4L03L4dmrzD6Ueap4Slg

I would think it would be to get the tire tighter on the wheel. 

15
ebruner
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5/20/2025 1:21pm
ebruner wrote:

That's correct, those are freedom coast.  I have those on one bike and a set of oak components on another. I prefer the oak components.  

AndehM wrote:
You put either of them on Mavens?  I know the PB review of both on TRPs preferred Oaks as well.  I was curious if they change...

You put either of them on Mavens?  I know the PB review of both on TRPs preferred Oaks as well.  I was curious if they change the Maven feel at all other than adding texture.  I don't have any issue with the stock Maven levers, but the Oaks look pretty.

8
kane
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Iederwangen CH
5/20/2025 1:49pm
I forgot to mention that 100mm OLD would also be 10% stiffer for the axle and for the arch.I remember various fork and component engineers shaking...

I forgot to mention that 100mm OLD would also be 10% stiffer for the axle and for the arch.

I remember various fork and component engineers shaking their heads in disbelief when the industry decided to settle on 15x110 rather than 15x100. Spoke triangulation has always been better for front wheels than rear, wheel manufacturers seem to chase front wheel compliance. 

I'm not sure that is correct when talking about the torsional stiffness because for a given handle bar / wheel torque spacing the fork legs further apart will reduce the force acting on them, causing a smaller deflection of each leg and a lower rotation angle of the wheel relative to the bars. This is obviously simplified but in general spacing fixings further apart improves stiffness, provided the hub and axle are stiff enough.  

2
trexyz
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RO
5/20/2025 1:51pm
Something new on the way from EXT?P.S I have a 190mm air spring for a fox 40 available for anyone looking to lower a set for...

Something new on the way from EXT?

IMG 2486 0.jpeg?VersionId=oxA89HS2VC

P.S I have a 190mm air spring for a fox 40 available for anyone looking to lower a set for their park / enduro setups 🙂 drop me a message if you’re interested

Cheaper rear shock from EXT

5
pinkrobe
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Revelstoke, BC CA
5/20/2025 2:19pm

Vorsprung are working on a 38/Zeb damper! 

19
PJ205
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Somewhere In, CA US
5/20/2025 2:28pm

I put Oak levers on my Maven's last week and rode them over the weekend. I originally planned to buy the Freedom Coast levers because one of the owners there/at Better Bolts has always been overly nice to me, but I got these for a good price at my job so I can't tell you the differences between the brands. I ride gloveless as often as possible so I bought the Oak's mainly because of the dimples on the lever only to quickly feel like they're almost a little too abrasive for my bare fingers. It was cold out so I wore gloves all day, but really appreciated the hooks at the ends of the levers being pronounced so your fingers are locked when braking and they don't slip at all. And they look good.

 

IMG 4478IMG 4480
7
Nobble
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5/20/2025 2:54pm
pinkrobe wrote:

Vorsprung are working on a 38/Zeb damper! 

The new Grip X2 damper is already superb. I’m curious how they could improve on it.


Maybe bring the shock retune tech from the Telum over to a drop in fork cartridge?

5
ebruner
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Tustin, CA US
5/20/2025 3:40pm
pinkrobe wrote:

Vorsprung are working on a 38/Zeb damper! 

This is pretty amazing news, where did you hear this from?  

1
pinkrobe
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5/20/2025 4:17pm
pinkrobe wrote:

Vorsprung are working on a 38/Zeb damper! 

ebruner wrote:

This is pretty amazing news, where did you hear this from?  

Somebody asked about fork dampers on Vorsprung's IG last week, and they said "sure", or words to that effect. I emailed Vorsprung asking if they could make a 38 damper, and they replied that Steve has designs started, there is no guaranteed timeline, but that they can likely make one that's cost competitive vs the GRIP X2 and Charger 3.1 dampers.

When I regained consciousness, I posted about it here.

25
5/20/2025 4:32pm
Something new on the way from EXT?P.S I have a 190mm air spring for a fox 40 available for anyone looking to lower a set for...

Something new on the way from EXT?

IMG 2486 0.jpeg?VersionId=oxA89HS2VC

P.S I have a 190mm air spring for a fox 40 available for anyone looking to lower a set for their park / enduro setups 🙂 drop me a message if you’re interested

trexyz wrote:

Cheaper rear shock from EXT

What I heard as well. 

Slavid666
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Santa Rosa, CA US
5/20/2025 4:36pm

From what I was told originally, he was interested in developing a complete fork. Steve said that the newer chassis out there are good enough to not make it worth their time to worry about a full package. It was about a year ago that he told me the fork cart was coming after the Tellum release, I've been patiently waiting ever since. I personally am not impressed with the charger 3 or the X2. I like my MRP V1 lift over both, and like my Ohlins TTX in the 38M2 over everything else. 

12
boozed
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AU
5/20/2025 4:46pm Edited Date/Time 5/20/2025 5:23pm
pinkrobe wrote:

Vorsprung are working on a 38/Zeb damper! 

ebruner wrote:

This is pretty amazing news, where did you hear this from?  

pinkrobe wrote:
Somebody asked about fork dampers on Vorsprung's IG last week, and they said "sure", or words to that effect. I emailed Vorsprung asking if they could...

Somebody asked about fork dampers on Vorsprung's IG last week, and they said "sure", or words to that effect. I emailed Vorsprung asking if they could make a 38 damper, and they replied that Steve has designs started, there is no guaranteed timeline, but that they can likely make one that's cost competitive vs the GRIP X2 and Charger 3.1 dampers.

When I regained consciousness, I posted about it here.

I hope they've considered total conversion sticker kits too.  For those forks that no longer contain any OEM parts.

I'm keen to see how this does against the Lift when it's available.  Having just worked out where to get one of those locally, now I suppose I'm going to wait a little longer!

Dave_Camp
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CO US
5/20/2025 5:20pm
Primoz wrote:
Yeah, it was included (had to even check it as I didn't remember).https://www.vitalmtb.com/forums/The-Hub,2/Are-Upside-Down-forks-really-flexy,11099?page=015 and 20 mm axles with thicknesses of 1, 2, 2,5, 3...

Yeah, it was included (had to even check it as I didn't remember).

https://www.vitalmtb.com/forums/The-Hub,2/Are-Upside-Down-forks-really-flexy,11099?page=0

15 and 20 mm axles with thicknesses of 1, 2, 2,5, 3 and 4 mm were compared. Thickness and diameter have an effect on torsion with USD forks, but still somewhat minor (roughly 10 % going from 10 to 20 mm with the same thickness).

While clamping width was tested I think the main difference was the stiffness of the 'dropout' as the whole assembly was bonded together. Ideally a system with realistic clearances would be simulated (and tested) to show real world differences as it will not be the same, even with pinchbolts clamping down on the axle.

FWIW, old 20 mm Maxles were interesting as they had expanding cones on both sides wedging themselves into the dropouts of the fork AND a step in the axle pressing the hub towards the NDS dropout (aligning the rotor every time) and possibly allowing some float in the dropout for the lower to run smoother. Come to think of it, do modern forks have more clearance in the bushings to offset this issue? @Dave_Camp any insights on this one?

The bushings are sized to give minimum friction without having to worry about customers complaining about bushing play.  Obviously misalignment from an under or oversized hub width is going to cause more friction, but the tolerances on the bushings are TINY and the basic rule is make the clearance as big as possible without crossing into the warranty loose bushing danger zone. 

I think floating axles are a small performance benefit, but I also enjoy the simplicity of the regular 15mm axle when I load a bike into the back of my car.  

8
Nobble
Posts
225
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9/24/2010
Location
Lakewood, CO US
5/20/2025 5:43pm
Primoz wrote:
Yeah, it was included (had to even check it as I didn't remember).https://www.vitalmtb.com/forums/The-Hub,2/Are-Upside-Down-forks-really-flexy,11099?page=015 and 20 mm axles with thicknesses of 1, 2, 2,5, 3...

Yeah, it was included (had to even check it as I didn't remember).

https://www.vitalmtb.com/forums/The-Hub,2/Are-Upside-Down-forks-really-flexy,11099?page=0

15 and 20 mm axles with thicknesses of 1, 2, 2,5, 3 and 4 mm were compared. Thickness and diameter have an effect on torsion with USD forks, but still somewhat minor (roughly 10 % going from 10 to 20 mm with the same thickness).

While clamping width was tested I think the main difference was the stiffness of the 'dropout' as the whole assembly was bonded together. Ideally a system with realistic clearances would be simulated (and tested) to show real world differences as it will not be the same, even with pinchbolts clamping down on the axle.

FWIW, old 20 mm Maxles were interesting as they had expanding cones on both sides wedging themselves into the dropouts of the fork AND a step in the axle pressing the hub towards the NDS dropout (aligning the rotor every time) and possibly allowing some float in the dropout for the lower to run smoother. Come to think of it, do modern forks have more clearance in the bushings to offset this issue? @Dave_Camp any insights on this one?

Dave_Camp wrote:
The bushings are sized to give minimum friction without having to worry about customers complaining about bushing play.  Obviously misalignment from an under or oversized hub...

The bushings are sized to give minimum friction without having to worry about customers complaining about bushing play.  Obviously misalignment from an under or oversized hub width is going to cause more friction, but the tolerances on the bushings are TINY and the basic rule is make the clearance as big as possible without crossing into the warranty loose bushing danger zone. 

I think floating axles are a small performance benefit, but I also enjoy the simplicity of the regular 15mm axle when I load a bike into the back of my car.  

What are your thoughts on suspension shops “sizing” bushings.


I’ve heard some people claim it’s mandatory if you want the fork to work right and I’ve heard others claim that it just makes your fork sloppy and loose.

2
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