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Hack Norris..

Wuffles

Monkey
Feb 24, 2016
157
98
Clearly there is some sort of translation issue going on here- "anti-pinch flat" for "tubeless systems". Tubeless already by definition precludes any sort of pinch flat since there is no tube to pinch. Now maybe this does help with blowing out sidewalls or dinging rims, but you know what else does that? Beefier casings.

Seems kind of like a solution in search of a problem.
 

landcruiser

Monkey
May 9, 2002
186
40
San Jose, CA
Clearly there is some sort of translation issue going on here- "anti-pinch flat" for "tubeless systems". Tubeless already by definition precludes any sort of pinch flat since there is no tube to pinch. Now maybe this does help with blowing out sidewalls or dinging rims, but you know what else does that? Beefier casings.

Seems kind of like a solution in search of a problem.
Pinch flats don't just happen to tubes. A lot of cut tubeless tires are due to pinch flatting the tire. Most of those little 1cm cuts right along the rim line are pinch flats. Even a lot of those straight line 1cm cuts right in the intermediate part of the tread are pinch flats. Whenever you pinch the tire between the rim and a hard object with enough force, something is going to give, whether it's a tube, the base of the casing, or the top of the casing.

Yes, a beefier casing helps prevent those pinch flats by increasing the material between the rim and whatever it's striking, but there's still room for a solution that reduces pinches in lightweight casings as well.

The concept of a floating protective layer inside a tubeless tire has been brought up many time, but I have yet to see an effective implementation of it.
 

troy

Turbo Monkey
Dec 3, 2008
1,006
739
How da f*ck do you pinch flat a tubeless tire?

Anyway, 70 EUR for a foam strip. Nice one.
 

Wuffles

Monkey
Feb 24, 2016
157
98
Pinch flats don't just happen to tubes. A lot of cut tubeless tires are due to pinch flatting the tire. Most of those little 1cm cuts right along the rim line are pinch flats. Even a lot of those straight line 1cm cuts right in the intermediate part of the tread are pinch flats. Whenever you pinch the tire between the rim and a hard object with enough force, something is going to give, whether it's a tube, the base of the casing, or the top of the casing.

Yes, a beefier casing helps prevent those pinch flats by increasing the material between the rim and whatever it's striking, but there's still room for a solution that reduces pinches in lightweight casings as well.

The concept of a floating protective layer inside a tubeless tire has been brought up many time, but I have yet to see an effective implementation of it.

As you said, those cuts are sidewall cuts or tread punctures. By definition, a pinch flat is what happens when a tube gets pinched between the tire and the rim and punctures without the external tire being punctured. You need a tube to pinch flat. They could have said something like "reduce sidewall tears" or something like that, but a pinch flat does not makes sense.

Regarding the lightweight casings- they're adding 70g (650b) and 90g (29er), which happens to be just about the weight difference between a maxxis skinwall and EXO/TR casing for most of their tires. If I was concerned about tearing casings, I'd just go with the beefier casing, skip this invention, and get some improved puncture resistance as well.
 

'size

Turbo Monkey
May 30, 2007
2,000
338
AZ
How da f*ck do you pinch flat a tubeless tire?
i've done it. mavic 819's with a wire bead DHF (not DH casing) set up tubeless. landed off a small jump and the rear tire hit a square edged rock just right i guess. snake bite just like the old tube days.
 

landcruiser

Monkey
May 9, 2002
186
40
San Jose, CA
As you said, those cuts are sidewall cuts or tread punctures. By definition, a pinch flat is what happens when a tube gets pinched between the tire and the rim and punctures without the external tire being punctured. You need a tube to pinch flat. They could have said something like "reduce sidewall tears" or something like that, but a pinch flat does not makes sense.

Regarding the lightweight casings- they're adding 70g (650b) and 90g (29er), which happens to be just about the weight difference between a maxxis skinwall and EXO/TR casing for most of their tires. If I was concerned about tearing casings, I'd just go with the beefier casing, skip this invention, and get some improved puncture resistance as well.
But the mechanism causing those cuts can be a pinch flat. The tire has been pinched between the rim and a hard object. A tear usually refers to a cut that happens after riding along or past a sharp object.

We're getting into semantics here, but using the term pinch flat with respect to a tire failure is completely appropriate (saying this as a former tire engineer).

I agree that a beefier casing is a better solution, especially for most of the readers of this forum. There's still riders who would prefer the supple ride of a thinner casing, while looking for fewer failures. If this product does that for them, great. I wouldn't bother personally.
 

slyfink

Turbo Monkey
Sep 16, 2008
9,289
5,029
Ottawa, Canada
As you said, those cuts are sidewall cuts or tread punctures. By definition, a pinch flat is what happens when a tube gets pinched between the tire and the rim and punctures without the external tire being punctured. You need a tube to pinch flat. They could have said something like "reduce sidewall tears" or something like that, but a pinch flat does not makes sense.

Regarding the lightweight casings- they're adding 70g (650b) and 90g (29er), which happens to be just about the weight difference between a maxxis skinwall and EXO/TR casing for most of their tires. If I was concerned about tearing casings, I'd just go with the beefier casing, skip this invention, and get some improved puncture resistance as well.
Just last week I "pinch flatted" my Slaughter GRID tubeless tire in the exact manner landcruiser described. In fact, I go through about 1.5 tires a season in this manner. It's a rather annoying habit, and expensive to boot.

26 Butcher DH: 1250g
26 Butcher GRID: 900g.

1250g is too heavy. I can deal with 900g. I also generally find the 900g casing to be about right for my style of riding and my terrain.

If this things works, it would be ideal for me. @landcruiser, I'd be interested to hear more about this: "The concept of a floating protective layer inside a tubeless tire has been brought up many time, but I have yet to see an effective implementation of it."
 

landcruiser

Monkey
May 9, 2002
186
40
San Jose, CA
If this things works, it would be ideal for me. @landcruiser, I'd be interested to hear more about this: "The concept of a floating protective layer inside a tubeless tire has been brought up many time, but I have yet to see an effective implementation of it."
Well, that's effectively what this Huck Norris thing is trying to be. It's a protective element that's not rigidly held in place inside the tire. It's a hard balance to actually meet. In terms of allowing the element to float, you don't want to affect the ability of the tire to conform to terrain but you have to grantee some sort of constant alignment between the protection and the rim. In terms of material, low weight and energy absorption don't usually go hand in hand. In my limited experience with using foams around tires for other projects, the density required to actually support rider weight and prevent tire damage is quite high.

@slyfink if your primary problem is pinching the tires, I'd look at Maxxis Double Down casings. Like DH tires, they feature rubber Apex inserts inside the casing at the bead to reduce pinch flats. The fabric layers in Specialized's Grid tires can't compete with that.
 

SuboptimusPrime

Turbo Monkey
Aug 18, 2005
1,658
1,633
NorCack
Not sure this is the way to get there but I buy the idea that there is value to blunting impacts between the tire tread and the rim. I've def cut a tire this way. Interestingly, Graves mentioned in an interview that he runs "ghetto tubeless" because he thinks the extra tire used to seal the rim and which basically sits between his rim and the real tire reduces his rate of "pinch flatting" tires.
 

slyfink

Turbo Monkey
Sep 16, 2008
9,289
5,029
Ottawa, Canada
Well, that's effectively what this Huck Norris thing is trying to be. It's a protective element that's not rigidly held in place inside the tire. It's a hard balance to actually meet. In terms of allowing the element to float, you don't want to affect the ability of the tire to conform to terrain but you have to grantee some sort of constant alignment between the protection and the rim. In terms of material, low weight and energy absorption don't usually go hand in hand. In my limited experience with using foams around tires for other projects, the density required to actually support rider weight and prevent tire damage is quite high.

@slyfink if your primary problem is pinching the tires, I'd look at Maxxis Double Down casings. Like DH tires, they feature rubber Apex inserts inside the casing at the bead to reduce pinch flats. The fabric layers in Specialized's Grid tires can't compete with that.
thanks landcruiser. I have a WTB Trailboss in their Tough casing on the way. I didn't realize Maxxis was releasing the Aggressor in 26 DD. When I last checked (maybe a month ago?) it wasn't an option on their site. If the trailboss disappoints, I will definitely be acquiring an Aggressor, and perhaps even a Minion SS, both in DD.
 

trib

not worthy of a Rux.
Jun 22, 2009
1,458
388
Looks like it makes the tire a little squarer. This has to be better than the THE rims from a while back that came with a massive plastic sleeve to try and reach the same result.
 

xy9ine

Turbo Monkey
Mar 22, 2004
2,940
353
vancouver eastside
was actually part of the rim extrusion. heavy, and absolutely heinous getting tires on there. has me wondering though - how about a cheaper / easier to set up procore-esque solution that's just comprised of a solid, small diameter foam noodle that stretches onto the rim? would be (should be) cheap & easy to set up. anyways, feast your eyes:

 

Happymtb.fr

Turbo Monkey
Feb 9, 2016
1,907
1,252
SWE
I did that on the back wheel of my hardtail and it works just fine: no more pinch flat, no burping and no more dented rim! I have used it now for a month and half.

The valve core on tubular is not threaded and I had a leak there until I threaded it with a M6 x 0,75 die which is finer than usual M6 (I don't know how much tpi that would be...). I also put a piece of tube through the valve core of the tubular before inserting it in the rim becauce I did not trust the fabric at the bottom of the tubular to be tubeless compatible...
I found out that 25mm tubular might be a little too wide for my i25 rims so that the tubular sits on the top of the rim walls and not on the rim bead. This could also explain the issue I had with the leak described above. I have 23mm tubular on their way. 21mm tubular were too small and did not push the tire against the side walls of the rim thus allowing burping...

28" tubular will work fine on 26" rims according to my experience. I not sure how it works on 27,5 rims so check your spoke tension after inflating the tubular!


About hack norris, the inventor did comment on a swedish forum that the stuff is made of PE foam and has a limited life length: it will also get cut like your tube or sidewalls after repeated pinch flat like moments.
Apparently it is something used in the mx world...
 

saruti

Turbo Monkey
Oct 29, 2006
1,167
73
Israel
Not sure this is the way to get there but I buy the idea that there is value to blunting impacts between the tire tread and the rim. I've def cut a tire this way. Interestingly, Graves mentioned in an interview that he runs "ghetto tubeless" because he thinks the extra tire used to seal the rim and which basically sits between his rim and the real tire reduces his rate of "pinch flatting" tires.
its interesting to see that Graves is flating every race this year, since he moved to regular tubeless
 

Gary

"S" is for "neo-luddite"
Aug 27, 2002
7,541
5,472
UK
its interesting to see that Graves is flating every race this year, since he moved to regular tubeless
No.
Enduro.
Therefore it is not interesting in the slightest.

Graves was one of the only dudes to regularly flat in 4X too. I'd be looking for my tyre advice elsewhere.
 

mtg

Green with Envy
Sep 21, 2009
1,862
1,604
Denver, CO
How da f*ck do you pinch flat a tubeless tire?

Anyway, 70 EUR for a foam strip. Nice one.
Brace yourself for some opinion, with a strong side of sarcasm.

I pinched a tubeless tire on Wednesday. Here's the recipe, it's so easy, you can do it yourself at home!
Step 1. Inflate tire to reasonable pressure (29psi rear for me)
Step 2. Ride
Step 3. When you get to that rock garden that you normally slow down for, don't. Try to gap it.
Step 4. Woops, my rear wheel tagged something sharp
Step 5. Now you have a slashed, pinch flatted tubeless tire

I think Huck Norris is a good idea. It's cheaper than Procore, lighter, simpler, and shows promise to reduce pinch flatted tubeless tires. I've tried a few similar ideas of my own and haven't nailed it yet, whereas it looks like they have something that likely works.

As far as the "it's so expensive for a piece of foam" argument....there's more to it than you're realizing. I've spent time looking into different foams for the same purpose, and if you think you're going to go down to a hardware store and tell them you want a foam that does exactly this for 50 cents, you aren't. I tried a foam in my tires last year, and it didn't work, looked into some other foams, realized it's pretty difficult to find something that will actually provide cushion without weighing 200g per tire (or more), shelved the idea, recently tried again with another foam, it didn't work, inquired with the local rubber and foam supplier, and their response was literally "we are going to no-quote this".
 

troy

Turbo Monkey
Dec 3, 2008
1,006
739
@mtg fair point. I always thought pinch flatting is reserved for tubes only and the situation You have described is just a slashed/cut tire.

What kind of foams have You tried? You should check out some military grade foams or Rubatex products...
 

mtg

Green with Envy
Sep 21, 2009
1,862
1,604
Denver, CO
@mtg fair point. I always thought pinch flatting is reserved for tubes only and the situation You have described is just a slashed/cut tire.

What kind of foams have You tried? You should check out some military grade foams or Rubatex products...
A pinch flatted tubeless tire does end up cut/slashed, the cut will be on the tread and/or by the bead. That's just about the only way I get flats these days.

The first foam I tried was the "I have this laying around and it's cheap/free" variety. It was an open cell, probably PE foam, not heavy. It absorbed the tire sealant and didn't really provide any noticeable cushion. The second one, I'm not sure what it was. Originally I thought it was a low density closed cell foam, but after pinch flatting, when I pulled the tire off the rim, that has also absorbed the sealant, so it was also open cell.

I'll check out Rubatex.
 

SylentK

Turbo Monkey
Feb 25, 2004
2,287
854
coloRADo
I am skeptical at best. The claims they make under the "what huck norris does" seems a bit overhyped imo. Actually, impossible. My take is that it might help you in case you tag that sharp rock it is supposed to cushion the blow. I would not trust it with lower pressure.
 

Jm_

sled dog's bollocks
Jan 14, 2002
18,855
9,560
AK
I am skeptical at best. The claims they make under the "what huck norris does" seems a bit overhyped imo. Actually, impossible. My take is that it might help you in case you tag that sharp rock it is supposed to cushion the blow. I would not trust it with lower pressure.
Instead of running 5 more PSI for that one in a thousand sharp rock, it's important to lug around a bunch more weight all the time.
 

Kanye West

220# bag of hacktastic
Aug 31, 2006
3,740
470
This doesn't act as a bead lock in any way to prevent burping like the ProCore/Nuetech Tubliss ripoff, right?
 

vinny4130

Monkey
Jun 11, 2007
450
207
albuquerque
I'm stoked to see a 700c would go around a 26" I just assumed it wouldn't so when I did this I used 650c tubulars. Worked great just a tad heavy. Maybe the next 650b DH bike will use the 700c.
 

Happymtb.fr

Turbo Monkey
Feb 9, 2016
1,907
1,252
SWE
I tried a 23mm tubular, Vittoria Rally which can be found quite cheap here in Europe, it fitted nicely between the sidewalls of my i25 rims. The 28" or 700c tubular needed around 8 bar / 115 psi to make contact with the 26" rim.
If used on 27.5 rims, check your spoke tension while inflating and 8 bar is likely to be too much for this wheelsize.
 

Happymtb.fr

Turbo Monkey
Feb 9, 2016
1,907
1,252
SWE
Have you seen that on one of the Demos at WC
Apparently it did not help against burping, the rim might be untouched...? ;)
hack norris II.jpg