Flat tires suck, plain and simple, especially if they happen during a race run. That 'pssst' of air escaping, followed by the feeling of your rim hitting the ground is gut-wrenching, and something that still happens far too often, even to the best racers in the world. Just ask Aaron Gwin, Greg Minnaar, Jared Graves, or Richie Rude how they felt when they got flat tires this season.
CushCore Details• Closed cell foam
• 27.5 and 29" options
• Fits tire widths 2.1 - 2.5"
• Fits rims with internal width 22 - 35mm
• Weight: 290 grams (29" version)
• Price: $149 USD (pair), $76 (single)
•
www.cushcore.com Schwalbe's ProCore system kicked off the tire insert party nearly three years ago with their tire-within-a-tire design, but more recently we've seen a number of foam inserts hit the market that are designed to help prevent pinch flats and damaged tires. Huck Norris, Flat Tire Defender, and CushCore have each released their own spins on flat prevention, but they're all designed around the premise that a section of foam placed in between the tire and rim will help keep the tire's sidewall from getting pinched and potentially sliced against the rim during an impact.
CushCore is made from closed cell foam that's been molded into sort of a T-shape, with the narrower portion sitting in the rim bed, and the upper part extending over the sidewall. CushCore doesn't just bill their system as something to protect against flats – they call it an 'Inner Tire Suspension System', claiming that the insert acts as a damper, with the air in the tire above the insert acting as the spring. That's supposed to lead to better traction, cornering, as well as a smoother ride in rough terrain. Does it work? That's what I wanted to find out.
The kit, which includes two inserts and two valve stems, retails for $149 USD, or a single insert and valve can be purchased for $76. CushCore is currently only available for 27.5 and 29” wheels, but 26” and 27.5+ kits are on the way. Even though it's “just” foam, the inserts aren't super light – our 29” version weighed in a 290 grams per insert. However, the protection that the insert provides may allow some riders to run a lighter weight casing than usual, which would help counteract a portion of that weight penalty.
The CushCore insert is designed to work with rims from 22 - 35mm, and tire widths from 2.1 - 2.5".
InstallationThere's no getting around it – installing a CushCore system can be a royal pain in the ass. A lot of that has to do with the tire / rim combination, and familiarity with the process. Once you've done one install, the next one is easier – at the very least you'll know what to expect.
Before going near any tools, I'd recommend putting on some soothing music, doing some meditation and deep breathing, and possibly consuming an adult beverage or three in order to ensure that you don't end up snapping tire levers and throwing your wheel across the room in a fit of rage. Once you're all Zenned out it's time to grab everything and get to work.
CushCore recommends stretching the insert over the rim first, and then installing the tire, working your way around one side of the tire at a time. Don't do that. I found that getting one side of the tire seated on to the rim, and then sticking in the CushCore insert was much easier. That way, once you get the insert into place all that's left to do is dump in a couple scoops of sealant and get the other side of the tire seated. Of course, that's easier said than done.
The hardest part of the installation will be getting the final eight inches or so of the tire beat to pop over the rim's sidewall and into place. Be patient, and work your way around the rest of the tire, tucking the bead into the center of the rim as much as possible. This should help create enough room to pop that bead into place, although it probably won't be easy. A spray bottle of soapy water and strong tire levers are going to be very helpful at this stage.
PerformanceI don't usually get a ton of flats (knock on wood), but with the Whistler stop of the Enduro World Series looming on my calendar, I decided to install a CushCore insert in my rear wheel for a little extra peace of mind. I typically run 23 psi in my rear tire, but after some experimenting settled on 20 psi with the CushCore insert. Running a CushCore insert is similar to installing volume spacers in a fork – it allows you to run a little less pressure without worrying about bottoming out. And believe me, I smashed that wheel into all sorts of things – curbs, rocks, roots – and the rim survived without any damage at all.
The insert also adds sidewall support, which helps keep the tire from folding over in hard turns. Even at silly low pressures it feels like it's only the top 1/3 of the tires that's really moving around – the rest stays the same shape thanks to the insert, and no matter how hard I tried I couldn't get the tire to burp or peel off. There's a more muted feeling when you hit something hard, similar to the way a dead blow hammer behaves, or a medicine ball. In rough sections of trail it felt like my rear wheel wasn't getting bounced around as much, giving the bike a more planted feeling - it's genuinely impressive how much of a difference such a simple product can make.
After weeks of running the CushCore insert without any issues, I did still manage to get a small puncture on race day – even with a Maxxis DoubleDown tire a sharp rock was able to jab through the center of the tread. Luckily, the slit was small enough that the sealant helped slow down the amount of air leakage, and I was able to add more air and finish the last stage of the day. Punctures or slices are scenarios that CushCore can't completely prevent, but I think it does help – it limits just how far a sharp object can penetrate, which could reduce the amount of damage that occurs.
Pinkbike's Take:  | If you're continually plagued by pinch flats, or can't seem to keep your tire from blowing off during hard cornering, I'd highly recommend CushCore. Yes, it can be tricky to install, and it's not light or cheap, but when compared to the alternative – flat tires and dented or cracked rims – CushCore starts looking more and more appealing. — Mike Kazimer |
- Me
That's when I cut a Pool Noodle into the shape of my rim and tape it on there.
Wish me luck
cush core system, $150
pool noodle system $3.50
knowing you're only out $3.50 for a system that works as equally as $150 (trend); priceless.
The benefits far outweigh any harm you might experience using Cushcore....
IMO
@fedemeta, I assume that Huck Norris makes wonderful sculptures from the sealant. AKA Stanimals.
www.instagram.com/p/BW4ZlRsAmer/?taken-by=angrybikemechanic
I have been running CushCore all season in Whistler and can honestly say they are worth every penny!
Yes they arnt cheap but the amount of money you save on inner tubes and rims far outweighs the cost of Cushcore.
And it improves the ride and feel of the bike a lot + let's you run LESS AIR!! Worth every penny guys!!
my solution: wrap the noodle in fibre glass tape at 90deg to the direction that the rim will impact it, the tape will not tear and will give the noodle that outer skin it needs.
My advice after the experiment: it totally works and is much cheaper than any retail alternative, but unless you use at least 30mm thick pool noodle you will still damage your rim, even if you dont damage your tyre in big impacts
what i learnt: the tape at 90deg to the rim bead is brilliant and will stop the snake bites in the foam and help your insert survive longer, whatever insert you used (I've since changed to another insert, but still wrapped it in tape) the problem is that it gets in the way of your sealant flow, only i'm not sure if that is actually a problem or not because i cant see inside my tyre
That being said, I will switch to a Cushcore once they make them for 27.5+ in a month or so.
Other than that its pretty rad and not too bad to install with lots of soapy water.
I have only one set of wheels. At the moment set uo tubeless with cross country tyres. Say this weekend I want to do a shuttle day, changing to DH tyres. When I unmount my xc tyres, which have only been on for two weeks, can I just leave them leaning up against the wall for a day or two with the sealant in, and then put them on again? Or will the sealant be ruined? Should I use bulldog clips around the bead to keep the two sides together?
That Stan's ain't cheap, so I don't want to throw it out every time I change tyres.
What do you reckon?
@jaame - However I would personally recommend finding a cheap second hand rear wheel for DH. I've done a lot of remounting/resealing this year and it's just a god damn pain in the bottom. I mention back wheel because I run my front wheel with tube anyways. I do puncture the front occasionally but it's a hassle either way.
/Wacek
I was planning to get another set of wheels with hope/dt swiss... but I changed my mind. I'm getting a road bike instead, then I won't need to do xc for fitness anyway
I use split tube ghetto tubeless and you get a reasonably good seal between the tyre and split tube without sealant so reckon I could use the bare minimum to seal the tyre joint - maybe 30ml
I also rarely get flats (touch wood) which are mostly thorns and don't race so time is not an issue if I have to use a plug and pump up the tyre.
I guess the other issue is air leakage but I generally check my tyres before every ride.
Anyway its worth a go if you aren't racing.
Install was pretty straight forward, followed their instructions with soapy water on the first one. made a big mess in the living room and got into trouble with the wife...
installed the second one without water and it actually worked better because the stuff wasn't slippery as f##k and I could push it into its placeway easier.
bottomline, grab the whole tire and insert, bend it so the tire can slip under the insert and the bead sits all the way in the sent or the rim, if you do that and start opposite the the valve it works like charm.
wasn't even able to finish a single beer it went so smooth and quick...
only problem, the supplied valves don't really fit enve wheels, stay with the enve ones! they work just fine!
It can be a problem with normal valves because air pressure makes the inser block the valve hole.
@SlodownU: I broke one of my rims the second day i was riding them going through a rock garden.
they came with the bike and i would have definitely not bought enves... hate their stupid nipples and DT centerlock stuff.
I decided to try the cush core because i destroyed tons of rims both alloy and carbon in the past and this time had to wait good 5 weeks till i got my replacement wheel and i really don't want to not ride my new bike for that long again...
Anyways, I really like the stiffness of carbon wheels compared to alloy ones specially on the big wheels...
-rider buys (insert brand here) insert
-rider drops psi because more traction and new possibilities
-rider starts getting cocky
-rider blows through insert and still ruins rims and tires
These guys were all running inserts when they flatted this season.....
not saying they aren't useful, just that it's a pretty ironic statement to make, considering....
can see it here, both the enve insert and the foam: ep1.pinkbike.org/p6pb15097177/p6pb15097177.jpg
Install was way easier than everyone whines about. Follow the video instructions carefully and it's really not that bad. Maybe I just got lucky with my tire rim combo, but it really wasn't bad at all.
Secondly, my reason for getting them was 2 parts. First I just want to ride trouble free for as long as possible. I don't get to ride as much as I like, so nothing is more of a bummer than having to waste time fixing a flat or dented rim. Secondly, $150 is pretty cheap rim insurance. I just bought a new wheelset and I wanted it to last.
So far, no dents or flats. I have run them on really low pressure, and they do their job. I will say, surprise benefit they do "soften" the ride a little. The foams acts as a bit is suspension, and I honestly do feel like they have helped in the arm pump battle.
I went with a lighter sidewall tire as suggested. I will say I feel the weight a little on climbs. Not a huge deal to me as I ride a lot of park, and when I ride real trails, I have no problem putting it in the granny gear and taking my time so I can enjoy the down more. If you're a weight weenie, obviously not for you, but I just want my bike to be as indestructible as possible so I can have the most fun, and for that reason I love them and will keep using them.
Everyone on bottoming out shocks: What pressure you running? What's your sag? What's the rebound? Do you have any bottomless tokens in place? Can we look at your progression curve? Have you tried a ramp cartridge?
Back then i switched to a 2.8 michelin dh comp to fix my pinch flatting issues, seems like 2.6 minion wasn't enough.
Could we rather get a comparison with the other alternatives (procore etc)?
Inserts aren't cheap and comparative info is scarce
www.instagram.com/p/BXv5mlxjZ7P
I installed these on my hardtail and am completely sold. Running cross country tires paired with fairly light rims so overall weight is not crazy. I weight 155lbs .Beyond the obvious benefit of being able to drop from 27psi on the rear to 22psi on a hardtail, the amount of support and dampening that this gives the tires is crazy. Can slam corners and tires feel stable, this was not the case when I was running 27psi without cushcore. The tires really do feel damped which translates into more chassis stability, less fatigue, more predictable drift, less rolling resistance in high amplitude bumps.
Why not just run a heavier weight casing (which is probably less added weight than this) with tougher sidewalls that don't get cut so easily, chunkier sidewalls also dampen better so that gives you the improved cushioning too.
It's also just as expensive as a new rim and if you do still puncture out on a ride its going to make removing it and putting a tube in trail side a royal pain in the a$$.
I guess at least we are trying to improve the puncture issue, this just has too many negative side effect in my eyes especially the weight in an area we all agree it makes a big difference.
Why is it better than a DH tire setup as tubeless? Because it a) prevents burping since it holds the tire to the rim more securely and b) prevents pinch flats even if that is harder to get with thicker DH casing tires
I was running DH tire with tubes for year and though flatting was not so common I still managed to damage rims, especially rear ones. After two years running singleply tires with schwalbe procore system I know I will never go back! Way more grip=way more confidence, no more flats ever and it is lighter!
I run DH casings on all of my bikes personally...not going for any records on the climbs, so why not
While i don't see harm in running this if you want i don't think the advantages are very big or outway the disadvantages.
in response a) I run Spank rims with beadbite which adds zero weight and holds the bead like glue, never burps and i recently changed my tire and even with no air in i had to use quite a bit of force to unseat it, so absolutely no need to make that more secure if you have the right rm.
b) Pinch flats are only a real issue with tubes and with tubeless id argue a thicker tyre is less likely to get cut by a sharp rock that a thin tyre with cushcore, yes cushcore with stop your rim cutting the tyre but ive never found that an issue, sharp rocks on the other hand will cut a thin tyre.
As for it being lighter a Double Down or Super gravity tyre is approx 200g heavier than a trail tyre and a DH tyre is 200g further so whichever tyre you usually run one step up in tyre is only 200g vs 290 for cushcore.
I just know how much difference rotational (and unsprung) weight makes having changed rims a few years back saving 200g per wheel and i instantly noticed the difference.
I have run Tubeless with super gravity tyres (saving further weight over DH tyres) on my DH bike for years and cant remember my last puncture, even after weeks in the alps and races at Fort william. admittedly i am only 70kg, bit more with kit, but this is probably why i can get away with things more.
i will admit the one and only thing maybe worthwhile with cushcore is stopping rim dents with lower pressures as i have dented rims (although never causing a puncture) but the weight and fitting hassle just isn't worth this alone.
I would be tempted to try Huck Norris tho as my spank rims mean i don't need the cushcore to hold the tyre bead but it will help protect the rim for a much more acceptable 70-80g weight penalty, and much simpler and cheaper.
Sorry that got a bit long...
Well if it works for you great!
I just love the advantages of the insert system. The added grip even with a less grippy compound compared to DH super soft durometer is mind blowing! I can ride offcamber roots and rocks like never before!
Before I was running super gravity tires with tubes and going to single ply tires with procore I still lost weight off the bike. I heard so many nightmare stories from friends that I never tried tubeless for mountainbiking.
Now all that was great but I really appreciated not having my back wheel full of flat spots at the end of every lift season!
I am interested in cushcore as an alternative to procore if I upgrade to some bigger wheels next year seeing as it is slightly cheaper.
@mikekazimer
Given that these are, at best, a bit tricky to install in a shop: how have you dealt with flats in the wild? Can you get the tire off, core out, and do the necessary repair in a reasonable amount of time? Then do you shove the core in a pack for the remainder of the ride?
For context, I am 80kg, run 2.5 DH casing DHR2 on 31.6mm internal carbon rims.
I usually run 38psi in the rear in Whistler BP, and my sidewalls still get threadbare criss-crosses before the tread is worn out completely.
I realize 38 is higher than almost everyone. But at 26 psi I would destroy the sidewalls in a few days of park riding (and my rims). As for traction, in dry conditions it hooks up much better at high pressure than at low pressures like 20psi, where I find it just starts breaking loose and keeps going because there is no support for the knobs to bite under hard cornering.
When I had narrower Mavic 823's with UST Minion DH's (shitty sidewalls) I used to run 30psi front and 40psi rear and flat all the time. After my 2nd flat of the day and hearing about the 4th person suggest it was because my tires were too hard, I tried 25 and 30; first corner I flatted front and rear tires so back to 30/40 I went. It wasn't until I went carbon rims that I could drop it to 28/38 and get almost no flats, but still occasionally crack rims. After procore, I thought it would be cool to go really low, but I settled on 24/32 in the dry and don't like the feeling of anything less. After blowing the procore in the rear, I'm back to just running 38psi and no insert. I do like the front procore so I can run 24 without cracking rims, which for me is just not possible without it.
Anyway, long boring story over. From my perspective I'd say it's all about preference and riding style above all else. I don't know anyone else running as high as I do, but it works for me.
I imagine CushCore and Flat Tire Defender offer a much more pronounced dampening. And MrWolf's Banger probably even more.
Well, I used to do the same.
I ran the minions at 38 PSI to stop them from giving me flat rear tyres all the time. Also, even those heavy reenforced tyres tend to bounce to much at those pressures. I think it makes ProCore even more of an archivement that it stopped me from flattening, allowed me to go tubeless and with about 10 PSI less I got more grip and less flats.
The minions also tended to move on the rim under hard braking and if I wasnt careful I sometimes ripped the valve stem out of the tubes. Another problem ProCore solved entirely. I am full of love for the system.
@sp00n82:
If ProCore feels like a 2 step tyre you need to play with the pressure more in the outer and less pressure in the inner tyre. after fiddling for about 20 runs I got it dialed and wont ever go back to riding without. At least as long as this bike only sees bike park and lift service
both should provide the same benefits right ?
You may still flat sometimes, but so far none of these expensive magic bullets have actually solved that problem, and they make fixing the inevitable flat exponentially more annoying. You may damage a rim sometimes, but again...same rules apply.
/endrant
Just like it took years for tubeless tires and rims to get truly reliable, this is (for all intents) a beta product and you get to pay too much money to help develop the final, sorted version if you buy it.
One final thought-the claim that you can get away with lighter tires using an insert strikes me as specious. I don't wreck rims (at least if they're strong enough-currently running WTB Frequencies), but have grendaded several tires with lighter casings (esp. on the rear wheel). Switching from something like a Maxxxis DD casing to an EXO casing and then slamming through rock gardens at speed is a recipe for a massive casing cut across the carcass of the tire. The insert on the far side of that casing from the rocks won't do squat to prevent that. In fact, if the tire feels more supported, it'll happen sooner. So...like I said-this technology needs to be holistically incorporated into a rim/tire/insert design to optimize function (and minimize weight).
The install sucks.. But more beer = less suck
Hmmm...
Rider weight 85kg, 25mm internal width, and zero flats on rocky and rooty trails.
Like: adjust pressure for better feeling and grip and not worrying about flats.
Don't care about weight
Conclusion: Best upgrade by far! You pay for performance and not bling!
PS - I've ditched extra-tubes and pump (yes I know... but 1 year/zero flats adds a lot of confidence, until "The Day". Until then... no extra weight besides Procore)
If your valve leaks or air escapes the central chamber, the impregnanted 18 psi external "core" remains and you literally do NOT flat. Ever.
so here's a fact.... I ran these all summer, going out almost every day...... my wheels are still true after hundreds of lines shot down Steven's pass's gnarliest rock garden at pretty decent speeds, for a good chunk of the year. I believe in these systems. Tried a pool noodle and got one ride out of it before it was shreded in my tire.... messy.... dont do it.
Cush core takes a while to install for a noob. But it's worth it for a pro. Suck it up boys, and ride faster.
I replaced them with my whatever brand of tubeless valves which have a larger rubber "stopper".
This prevented the air leakage I was getting, this is good, the only problem now is i cannot let air out of the tyre as i pumped it up to 50psi to get a secure bead,.
I removed the tubeless lock ring and then pushing the valve back into the rim to let air out, but it worked. the cushcore valves are special , i.e. they have some cut outs. so you can add sealant remove air etc.
what i will do next is remove the tubeless valve and cut a small section out which will hopefully give the option to normally add sealant or remove air.
Rim used Spank ozzy 345, tyres used Bontrager se5 and Minion dhr II
I don't like dinged rims, where we ride is all rock garden and sandstone.
that is all
Thats what she said...
with cushcore (did 3 rides with it this week) i felt more tiresupport -also no burping but a whole different trailfeel -the wheels bounce of obstacles far less and calm down much faster -i have beaten all my strava (descending) times around here during the week and conditions are not even completely dry. As i already stated above look at the smashtest vid of cushcore -you can see the regular tubeless tire wobbling after the impact -the one with cushcore calms down way faster.
www.bicidamontagna.com/shop-ita/kit-tubeless-e-valvole/1133-ptn-cerchi-29-e-275-pepis-tire-noodle.html
People worried about price...bike hobbies cost $$$ no matter which way you spin it.
Just installed with Minion EXOs. Didn't even use a tire lever. Soapy water was likely the key.
My Freeride Schwalbe tube is 200g.
www.urbandictionary.com/define.php?term=cush