Bent Rear Axle Bolts at Glendale - How?

501Ross
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2/3/2025 7:47pm

Was it Roczen talking about how gnarly the flat landings were on the press release?

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JM485
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2/3/2025 7:47pm

I don't think the OEM axles are as strong as most people believe them to be, I remember running a quick harness test on a Yamaha axle years ago and it wasn't anything special (essentially just mild steel if I'm remembering correctly).  If I had to guess the reason for this is likely wanting a fair bit of separation between the yield and failure points of the material, aka you want to know very early on that it's bending and replace it rather than having no warning and immediate failure, even if that failure is harder to achieve (think extremely hard but brittle materials like ceramics).  Or, maybe the OEMs are just cheap and I'm giving them too much credit, since even a cheap axle is good enough for 99.99% of riders.

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501Ross
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2/3/2025 7:49pm
I think I'm more impressed that there weren't any blown wheels with all those bent axles. Stout stuff.Wonder what the next weak link in the chain...

I think I'm more impressed that there weren't any blown wheels with all those bent axles. Stout stuff.

Wonder what the next weak link in the chain would be if they beefed up the axles? 

ML512 wrote:

Schock blew a bunch of rear spokes out trying it first in the morning. I'm not sure if anyone else did though.

Do some of the riders still zip tie the intersection of spokes together? I wonder if this also actually helps maintain the ridgidness of the wheelset?

Village Idiot
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2/3/2025 7:54pm
I think I'm more impressed that there weren't any blown wheels with all those bent axles. Stout stuff.Wonder what the next weak link in the chain...

I think I'm more impressed that there weren't any blown wheels with all those bent axles. Stout stuff.

Wonder what the next weak link in the chain would be if they beefed up the axles? 

ML512 wrote:

Schock blew a bunch of rear spokes out trying it first in the morning. I'm not sure if anyone else did though.

501Ross wrote:

Do some of the riders still zip tie the intersection of spokes together? I wonder if this also actually helps maintain the ridgidness of the wheelset?

My understanding is that this can increase the chance of a wheel failure since the spokes can't flex/deflect as intended and transmit more force into the hub.

3

The Shop

LungButter
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2/3/2025 8:14pm
My understanding is that this can increase the chance of a wheel failure since the spokes can't flex/deflect as intended and transmit more force into the...

My understanding is that this can increase the chance of a wheel failure since the spokes can't flex/deflect as intended and transmit more force into the hub.

Was it at A1 that Anderson was praising Kawi for wire tying his spokes cause it saved his race?


Always interesting to learn about the give and take with stuff. 

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Village Idiot
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2/3/2025 8:52pm
My understanding is that this can increase the chance of a wheel failure since the spokes can't flex/deflect as intended and transmit more force into the...

My understanding is that this can increase the chance of a wheel failure since the spokes can't flex/deflect as intended and transmit more force into the hub.

LungButter wrote:
Was it at A1 that Anderson was praising Kawi for wire tying his spokes cause it saved his race?Always interesting to learn about the give and...

Was it at A1 that Anderson was praising Kawi for wire tying his spokes cause it saved his race?


Always interesting to learn about the give and take with stuff. 

Can't say; I didn't hear/read the comment. Was he alluding to them being loosely tied so they didn't fling around and cause more problems or that he thought it strengthened the assembly? I thought his broken spokes at A1 came from a competitor's peg or something in the first turn, not impact/jumping stress.

I do remember guys in my youth using a heavy gauge solid wire to tie their spokes in an effort to strengthen the wheels, only to grenade them because they became too rigid.

2/3/2025 9:15pm

You have to remember they are on SX suspension. That stuff is s t I f f.

I'm surprised we haven't seen shock bodies split.

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Bearuno
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2/3/2025 10:48pm
mrpip wrote:

I didn’t hear the interview, but was he talking axles or chain adjuster bolts? I’m thinking chain adjuster bolts was more likely.🤷‍♂️

ML512 wrote:

Axle.

Like mrpip, I wondered if it was the adjuster bolts, or the axle, with that quote / wording from Dylan ( I haven't listened to that interview, yet) so, thanks for the info, ML512 !

When I PDS'd my 500, I also machined back the axle slot as far back as I dared - around 15mm to my dim recollection -  for a longer adjustment / well, longer swingarm. But, with that, a std. Adjuster bolt , it would not be long enough, or, barely be in the thread of the swingarm. So, I made some longer, high strength bolts, but also made  20mm x 20mm spacers to go between the swingarm and the lock nut - I've seen far to many adjuster bolts, even in std. swingarms,  cark it over the years.

I was wondering about the damage totals over the night, with those HUGE slap down, flat landings - I'm so glad we didn't see an exploding wheel / shock 'Et al',  and an accident from such a thing.

philG
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2/4/2025 4:21am
philG wrote:

used to bend them flat landing to tarmac at Supermoto, and the middle of the axle used to move forward, not up, which was nuts

Graybeard wrote:
Man, that had to be sketchy as heck, to do it lap after lap knowing what was happening at the rear wheel! How do you not...

Man, that had to be sketchy as heck, to do it lap after lap knowing what was happening at the rear wheel! How do you not explode the wheels first? I would have thought the spokes, hub, or rim would be a weaker point than the axle!

We bent a few wheels, but like the SX guys, who rolled the wall , we didnt do it unless we had to, but a couple tracks it was a case of send or go home, so you did it.  And we are running way stiffer suspension and slicks with 25 PSI in them as well. 

SM wheels have a hard life, especially if you come up short anywhere. 

 

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AMetts
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2/4/2025 4:48am
My understanding is that this can increase the chance of a wheel failure since the spokes can't flex/deflect as intended and transmit more force into the...

My understanding is that this can increase the chance of a wheel failure since the spokes can't flex/deflect as intended and transmit more force into the hub.

LungButter wrote:
Was it at A1 that Anderson was praising Kawi for wire tying his spokes cause it saved his race?Always interesting to learn about the give and...

Was it at A1 that Anderson was praising Kawi for wire tying his spokes cause it saved his race?


Always interesting to learn about the give and take with stuff. 

Can't say; I didn't hear/read the comment. Was he alluding to them being loosely tied so they didn't fling around and cause more problems or that...

Can't say; I didn't hear/read the comment. Was he alluding to them being loosely tied so they didn't fling around and cause more problems or that he thought it strengthened the assembly? I thought his broken spokes at A1 came from a competitor's peg or something in the first turn, not impact/jumping stress.

I do remember guys in my youth using a heavy gauge solid wire to tie their spokes in an effort to strengthen the wheels, only to grenade them because they became too rigid.

Yeah they don't add any strength at all but when you break a spoke it hopefully keeps it from getting tangled into something. 

DH mountain bike guys have been doing this a long time and those guys are freaks about spoke tension they change it as a setting like a suspension clicker, so id think if it hindered flex at all they wouldn't be doing it. 

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wvumounty
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2/4/2025 5:07am

The pro rider is a different animal. I have always wanted someone to do a post race “ pit bits”. Ripped graphics, grips, pictures of tires, frame wear, engine cover etc.

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PNWMXer
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2/4/2025 5:18am
wvumounty wrote:
The pro rider is a different animal. I have always wanted someone to do a post race “ pit bits”. Ripped graphics, grips, pictures of tires...

The pro rider is a different animal. I have always wanted someone to do a post race “ pit bits”. Ripped graphics, grips, pictures of tires, frame wear, engine cover etc.

A few years back (on here I think) there was a picture of Roczen’s rear tire next to Tomac’s, after an epic main event battle. Ken’s looked like you could line up next week on it…Eli’s looked like it had been ridden on the freeway. 

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Village Idiot
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2/4/2025 6:29am
LungButter wrote:
Was it at A1 that Anderson was praising Kawi for wire tying his spokes cause it saved his race?Always interesting to learn about the give and...

Was it at A1 that Anderson was praising Kawi for wire tying his spokes cause it saved his race?


Always interesting to learn about the give and take with stuff. 

Can't say; I didn't hear/read the comment. Was he alluding to them being loosely tied so they didn't fling around and cause more problems or that...

Can't say; I didn't hear/read the comment. Was he alluding to them being loosely tied so they didn't fling around and cause more problems or that he thought it strengthened the assembly? I thought his broken spokes at A1 came from a competitor's peg or something in the first turn, not impact/jumping stress.

I do remember guys in my youth using a heavy gauge solid wire to tie their spokes in an effort to strengthen the wheels, only to grenade them because they became too rigid.

AMetts wrote:
Yeah they don't add any strength at all but when you break a spoke it hopefully keeps it from getting tangled into something. DH mountain bike guys...

Yeah they don't add any strength at all but when you break a spoke it hopefully keeps it from getting tangled into something. 

DH mountain bike guys have been doing this a long time and those guys are freaks about spoke tension they change it as a setting like a suspension clicker, so id think if it hindered flex at all they wouldn't be doing it. 

I'm assuming they very loosely tether them, versus tightly cinching like I've seen on off-road wheels, so it won't affect the action but act like a lasso if they break. I'm not a bicycle guy so I've got nothing to draw on from that arena.

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TBOLTUSA
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2/4/2025 6:35am

Regular guys bend pitbike axles all the time
That track had some big flat landings that did a number on the equipment

twotwosix
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2/4/2025 7:15am Edited Date/Time 2/4/2025 7:15am

Those damn wall jumps are brutal. Add in 3 quads (jump over the start is quad size to me) and those bikes took a beating. 

2/4/2025 7:30am Edited Date/Time 2/4/2025 7:34am

Do the teams uses oem axles?
or produce their own

High strength steel

 

mx317
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2/4/2025 7:53am

You have to remember they are on SX suspension. That stuff is s t I f f.

I'm surprised we haven't seen shock bodies split.

Like this?

splitshock.jpeg?VersionId=qPGRB6lOz9IHEh8ZE.
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pummel
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2/4/2025 9:11am

Hey ML it sure would be cool and interesting if you could get pictures or videos of these parts. I'd sure like to see Dylan's axle rolled on a strait edge  . Or a close up of JA21's broken spokes. 

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AMetts
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2/4/2025 9:22am
wvumounty wrote:
The pro rider is a different animal. I have always wanted someone to do a post race “ pit bits”. Ripped graphics, grips, pictures of tires...

The pro rider is a different animal. I have always wanted someone to do a post race “ pit bits”. Ripped graphics, grips, pictures of tires, frame wear, engine cover etc.

Id love to see this too but the manufactures will just see that as a lose lose situation. Pictures floating around of bent and worn out parts after one race isn't necessarily the best look for OEMs or Sponsors even though that's the reality. 

1
2/4/2025 9:24am

You have to remember they are on SX suspension. That stuff is s t I f f.

I'm surprised we haven't seen shock bodies split.

mx317 wrote:
Like this?

Like this?

splitshock.jpeg?VersionId=qPGRB6lOz9IHEh8ZE.

Yes, and Kenny's last year at Nashville.

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Village Idiot
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2/4/2025 9:49am

You have to remember they are on SX suspension. That stuff is s t I f f.

I'm surprised we haven't seen shock bodies split.

mx317 wrote:
Like this?

Like this?

splitshock.jpeg?VersionId=qPGRB6lOz9IHEh8ZE.

Yes, and Kenny's last year at Nashville.

I thought Kenny's was a result of the circlip letting go and the shock then coming apart as opposed to actually splitting? Or did it split first and that caused the flying circlip?

Never saw any photos of the falied shock so that's why I'm wondering.

mx317
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2/4/2025 9:51am

Yes, and Kenny's last year at Nashville.

Yes, teammates shock pictured. I was at Nashville and saw Kenny's wild ride through the whoops ending in a crash. I saw some SX valving stacks one time and I'm surprised more don't split! They have to build tremendous pressure when they slam through stuff like they do.

2/4/2025 9:54am Edited Date/Time 2/4/2025 9:59am
mx317 wrote:
Like this?

Like this?

splitshock.jpeg?VersionId=qPGRB6lOz9IHEh8ZE.

Yes, and Kenny's last year at Nashville.

I thought Kenny's was a result of the circlip letting go and the shock then coming apart as opposed to actually splitting? Or did it split...

I thought Kenny's was a result of the circlip letting go and the shock then coming apart as opposed to actually splitting? Or did it split first and that caused the flying circlip?

Never saw any photos of the falied shock so that's why I'm wondering.

It was reported the shock body split. The circlip was clearly visible flying out in the whoops, but it is clear that something catastrophic occurs in the landing prior.

ML512 reports on it here and says shock failure occurred before circlip ejected: https://www.vitalmx.com/features/ken-roczens-shocking-crash-sequence

Those pictures won't be coming.

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Village Idiot
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2/4/2025 9:58am

Yes, and Kenny's last year at Nashville.

I thought Kenny's was a result of the circlip letting go and the shock then coming apart as opposed to actually splitting? Or did it split...

I thought Kenny's was a result of the circlip letting go and the shock then coming apart as opposed to actually splitting? Or did it split first and that caused the flying circlip?

Never saw any photos of the falied shock so that's why I'm wondering.

It was reported the shock body split. The circlip was clearly visible flying out in the whoops, but it is clear that something catastrophic occurs in...

It was reported the shock body split. The circlip was clearly visible flying out in the whoops, but it is clear that something catastrophic occurs in the landing prior.

ML512 reports on it here and says shock failure occurred before circlip ejected: https://www.vitalmx.com/features/ken-roczens-shocking-crash-sequence

Those pictures won't be coming.

10-4, thanks. 

Yeah, I saw the UFO/circlip photo that everyone else likely saw but had heard that it was a circlip failure and never got clarification on the exact cause.

NotTheStig
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2/4/2025 10:07am
pummel wrote:
Hey ML it sure would be cool and interesting if you could get pictures or videos of these parts. I'd sure like to see Dylan's axle...

Hey ML it sure would be cool and interesting if you could get pictures or videos of these parts. I'd sure like to see Dylan's axle rolled on a strait edge  . Or a close up of JA21's broken spokes. 

From the latest team fried video 

Firefox Screenshot 2025-02-04T18-06-50.113Z 1.png?VersionId=CP0HVtKzioE5ioT

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Brent
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2/4/2025 5:49pm

..so, Ferrandis is able to bend the steel rear axle on his Hondas?   Broken spokes happen all the time, but the force needed to do this is just extreme, unless they are using non OEM axles?

If he is actually able to do that, what is happening with his back wheel bearings or the rear hub? you would think they would explode before the axle bent?

I'd love to see a photo of the damage...

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Idp57
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2/4/2025 10:36pm

I thought that Dylan was talking about the axel bolts not the axel.He sad that chain was coming off and on the rear sprocket because the wheel moved forward.

2/5/2025 1:58am
wvumounty wrote:
The pro rider is a different animal. I have always wanted someone to do a post race “ pit bits”. Ripped graphics, grips, pictures of tires...

The pro rider is a different animal. I have always wanted someone to do a post race “ pit bits”. Ripped graphics, grips, pictures of tires, frame wear, engine cover etc.

Great idea. 

CPR
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2/5/2025 3:38am Edited Date/Time 2/5/2025 3:39am
wvumounty wrote:
The pro rider is a different animal. I have always wanted someone to do a post race “ pit bits”. Ripped graphics, grips, pictures of tires...

The pro rider is a different animal. I have always wanted someone to do a post race “ pit bits”. Ripped graphics, grips, pictures of tires, frame wear, engine cover etc.

I’m all in on that idea 👍

I used to always find it interesting to look around at the end of the race to see what bikes were spitting coolant, who’s clutches were smoked, what parts wore the quickest etc.

Would be really cool to see it at this level, but my guess is that most of the teams/ sponsors would not be so keen.

Rickyisms
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2/5/2025 8:32am
wvumounty wrote:
The pro rider is a different animal. I have always wanted someone to do a post race “ pit bits”. Ripped graphics, grips, pictures of tires...

The pro rider is a different animal. I have always wanted someone to do a post race “ pit bits”. Ripped graphics, grips, pictures of tires, frame wear, engine cover etc.

Would love to see photos Tomac’s clutch stack after the motos at Southwick or Red Bud. 

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