Tire inserts - do you run them?

I've had very good results with cushcore, and the Trail version is the goldilocks version for me for the rear tires on my Trail, Enduro, and DH bikes. I run the XC version on my XC bike as well. 

I originally got cushcore back in the day right when it came out because I had just got a new to me used DH with Enves on it and wanted to protect them since I didn't have warranty and no money after that purchase. Since then, I have been a user on every bike. What is interesting is that I use XC on my DH bike and Pro on my trail bike. I have been considering going down to XC on my trail bike recently but I certainly smash way more unexpected rocks on my trail bike whereas I know where every rock on a DH track is so I feel better. I liked the idea of rim protection. Then I got used to the slightly lower pressure and have enjoyed that as well!

I have also broken 3 rims with cushcore in but my inserts show a million gnarly gashes that maybe they could have been worse without? or broken more without? there's so many conflicting experiences, thoughts, reviews, etc on whether to use or not. I personally think I will continue to use but just pair DD with XC on trail bike and DH with XC on DH bike. I was always on EXO+ with pro on the trail bike but even with the support of CC, the sidewall breakdown of EXO+ is just too soft. Ive managed a lot of years and a lot of gnarly stuff life that which is awesome! Through those experiences, I am ready to try something slightly different now. 

I was an insert denier until this winter... I've destroyed a freshly built-up FR541 (which I put on a rear wheel to replace an EX511 that lasted maybe a year and never survived Northstar season) by hucking into a root on upper Jugs.  That somehow didnt impact the sidewalls at all, but made a big enough well on the bead shelves so the system wouldnt hold air. It did not help to put tape pieces or rubber repair thingies to smooth it out too.

Given the NA prices for DT Swiss, I figured I can eat the cushcore price.  It would likely be different if we could get DT Swiss for European prices, though.

FWIW, I have been using Cushcore Pro rear, then switched to Tubolight inserts (Commencal MucOff used to run those before the new version came out), and now I'm using Vittoria's Airliner trail inserts. Same weight (100g), pretty much same size and foam thickness. I didn't feel much damping difference from the Cushcore pro inserts VS the Airliners, but I like that they are much lighter (260g vs 100g). Since I build my own wheels, I use expensive DT rims and I don't feel like paying a lot to replace them, I like to spend 36euro to have the peace of mind. So far, my rear rims stayed dent-less!

Huge cushcore fan and user here. Absolutely must have a Cushcore pro in rear wheels otherwise I will destroy them. The tire support for cornering is a nice benefit. I think I like the damped feel too, but that's definitely not the main reason I run them. I used to go through multiple rear wheels a year before Cushcore, which got really old. As others have mentioned, when I take a used Cushcore Pro insert out of my rear tire, it's completely knackered, covered in knife slits from the rim, which leads me to believe it's really doing it's job down there. I use the XC insert in my front wheels about half the time, but my front wheels and tires seem to last for an eternity compared to rear wheels and tires, so the XC insert up front is less of a must-have and more of a nice-to-have.

That said, I don't think everyone needs to run them. I think the best indicator of whether you'd benefit from Cushcore is if you're currently smashing rims, folding tires, or pinchflatting. If that's you, I think Cushcore is a great solution. If not, carry on.

I have used CC pro, trail and more recently vittoria airliner, which I think is a good compormise of protection and weight, as mentioned above.. but this is tire brand specific.. I have used previous and current version of Michelins DH22/DH34DH16 and for these I dont see you need any insert.. Contis, Schwalbe, Maxxis are a different story.

Team Robot is spot on with why you might need them. It's interesting reading everyone's different uses and setups.  Particularly Storm Racing with the thicker with skinny tyres and thinner with DH tyres. I get that, even if at first it makes no sense, especially as now my use has changed.  Also interesting to note that many DH pro's don't use them these days after the initial buzz, but I think almost all XC pro's, even some cyclocross and roadies use them to allow them to keep going until a replacement is available on the course.  Cobbled classics season, perfect evolution.

I live in the Alps and ride a variety of rocky and rooty trails so rim protection was important to me.  I'm pretty light so as tyre construction has got better that ability to run lower pressures for feel and grip, whilst having protection for big impacts, was important to me. I was on Rimpacts for years which worked well, then on something cheap and foamy when my Rimpact supply ran out. It lacked feel, on or off so I cut it down to be more like a CC XC, to get that little bit of protection. Conti's sideswalls in Enduro are so good these days that also helps. Tyres, since the CC first came out have evolved to be even better so this could be why inserts have gone down in populairty.  But alas, my cheap rim started leaking at the weld seam and I couldn't run tubeless so I am now on a tube and Conti DH which doesn't feel as bad it should, but I can't run super low pressure.  I would say that a modern DH tyre and big insert might be a waste as the sidewalls as increasingly better.

I run Cushcore Pro F/R on my park bikes in the summer. North east rocks EAT wheels alive, and they seem to help save the rims from this. I'll still get a good ding here and there, but the rims definitely last longer. The downside is slower acceleration due to the heavier mass, but that's somewhat compensated for by the extra mass helping to carry you through chunk. 

i'm in the same region (mid atlantic, southeast PA).  blue is my primary mountain and can attest to the rocks.  as a bigger guy (225+) that still rides fairly hard cushcore was a revelation for me. after my first day riding DH on them i was never going back. i never ate rims at the same rate as Charlie, but the wear and tear on them was certainly a consideration. 

to OP's question - my primary reasons for running CC are rim protection and sidewall support.  although the damping / dampening is certainly a nice benefit. 

 for my trail bikes, I run rimpact.  still gets me the rim protection and sidewall support, but with less weight penalty. 

No insert guy here. 

I'm around 265ish and have been on WAO Strife (dh) rims on dh casing tires for the past three seasons and no rim failures and no flats. I'm a pretty smooth rider, but ride pretty hard and live in the rockies and terrain can be pretty unforgiving. If that ever changes, might look into them, but for the time being, life is fine without them.

last two bikes i had the vittoria airliner in the back, new bike gets the new airliner enduro. 

Tire tech and rim flange designs have improved enough that I don't think there is a need for inserts anymore.
In fact, inserts can cause more headache than benefit. They can act as a lever and promote blow offs.

First hand account from one of our Enduro racers a couple of seasons back:
So, turns out it was my insert that was causing the tires to fail and blow off. I put a new tire on, did some rides, was practicing for the race this past weekend and the exact same thing happened. Luckily just in practice this time. Something to do with the insert puts too much pressure on the bead and they blow out. I don't believe they are deformed prior to blowing out, but the process of actually being blown off the rim is what causes them to be deformed afterwards. I raced with no insert on a DH casing and was all good and I kinda liked the no insert feel! 

In that instance, you'd think not landing straight on a landing is more to blame with the crash than the tire potentially blowing off because of a insert?

The instances where i've heard of tires getting levered off the rim from a insert has been in higher speed cornering scenarios, usually on natural terrain.

Mandatory rear inserts for all of my bikes and my rate of flatting has gone way down as a result. I mostly just do it to protect the tire and also rim to some extent.Running CC trail inserts in the rear of the enduro bike with front also on gnarly gravity days. SS hardtail gets XC insert in the rear and that has been working well with 2.3"ish trail casings and ~28psi. I can't imagine how many plugs I'd be using on the HT rears as the insert is covered in rim stab scars.

To Schwalbai's point, I could see how some combinations of stiff insert, stiff tire wall and rim type could make the insert act as a wedge or rigid member that couples the sidewalls together and levers the tire off in high load situations. I go with the CC Trail insert over the PRO to save 50g's but maybe the perforations and smaller cross section allows for more compliance and a better compromise  between protection and tire roll? 

Increasing rim profile area makes sense; decrease the pressure by increasing area. But something will still have to give when you pinch rubber between granite and high modulus carbon/aluminum and I'm betting it still going to be the tire or rim without some other member to dissipate energy. 

Remember when everyone started to use inserts in DH?  now hardly anyone uses them - XC wernt and now alot of them are.

some wheel brands are still hesitant to warranty broken wheels when Inserts were used.

I started having rim issues(yes i got caught in the insert game)  but when i Stopped using inserts the Wheels on the DH bike survived so much longer


 

I tried a few different inserts (CC XC, CC Pro, Tubolight, Tannus) when they took off, mostly with lighter weight casings, and hated them.  Besides the ride feel being yuck, they repeatedly warped casings.  Heavier casing with no inserts feels much better to me.  I'm a lighter rider, and don't ride a lot of rocks though, so that's a factor. But even if I did, I feel like it's way less hassle to just run DH casings, appropriate pressures, and decent rims.  Also, FWIW, 1 of the 2 rim failures I've had was with an insert.  (The other was just incredibly unlucky landing where the DD tire flatted and rim cracked, but aired back up fine after patching.)  Anyways, I wouldn't run them now even if you paid me, assuming I can pick my tires/rims.

I started using inserts a while back so I could run low enough pressures and not destroy my rims. I'm pretty light, 63kg with gear, and was going through 1-2 rear rims per season with DH tyres and tubes. Started with Schwalbe Procore at first then switched to cushcore, victoria and an amazon insert which takes up practically the whole tyre. Procore was cool but the valves get clogged pretty quick. Inserts allowed me to run singleply tyres, have the grip required for the terrain (low for natural and +3psi for bikepark) I rode with sidewall support.  
Since trying Schwalbe DH radials I only run inserts with singleply tyres for bikepark or very rocky terrain. For natural terrain radials provide all the grip I need. 

Remember in the vital 17 questions that loic said he runs cushcore in the front and rear. (I think). Which ya dont hear too much of these days except in privateers

Always cushcore pro in the back.

I do all day E-mtb adventures from my house to middle of nowhere places exploring. If I get an un-repairable flat you can ride home at least. 

It's saved me quite a few times now. I run one in the hardtail too to get super low pressures for a bit of forgiveness.

Like a lot of people, I am not very smart. Also, I have been riding tubes quite some time and when I switched onto tubeless back in 2018, on my Intense Tracer VP, I thought that will protect me from flats. I only knew DH tires, I didn't care much about wall thickness, soft compounds etc. But I learned with or without my will. The next year I got a 29” Foxy and kept flatting with tubeless. I got sick of this, after I ruined what should've been a good enduro race at the beginning of the season. This involved me struggling to put on a recycled DH tire from the World Cup on my rear wheel early morning on race day and a huge explosion sound, plus a lodge kitchen smeared with tubeless milk. Did I mention I am very very stupid?

Nobody sold inserts here back then, so I literally begged my friend, who ordered a pair of CushCore from abroad to share one with me. He agreed, I repaid him later, when the first import came to our shop. I never rode without an insert in the rear since then and I think I got 1 or 2 flats in this whole time. I think this should say it all.

For a long time I rode a CushCore Pro in the back and a Huck Norris in the front and they have been excellent for me. I once burped my front tire, didn't have pump with me, but still got home on 2 wheels, thanks to the Huck Norris. 3 years ago my e-bike came with some Tannus inserts which were also pretty cool and I liked them a lot. I rode my new Slayer without inserts on the first test ride one and a half year ago and killed a brand new perfect tire in one run. This says a lot too. I kindly remind you that intelligence is not my main strength.

In the last two years I have been pretty much riding whatever insert I had around on the back and tire without insert in the front and I can't remember flatting. But I do thing of putting that Huck Norris back.

I wholeheartedly recommend inserts to anyone who doesn't have tire/wheels sponsors and/or a personal mechanic.

That's pretty much it. Don't be stupid like me!
Mx

Throwing in my 2 cents - I’ve had very good luck running rim saver inserts: https://www.savetherims.com/?srsltid=AfmBOop7KinRNnjwigDuUX5L9IT4FgTlIUBT2qJZ2bBNrLiDaaS1Le5c

They’re great if you don’t want to change your “tire feel”, but just want to add pinch flat protection/rim protection. Added bonus is they last much longer than a foam insert that gets cut up by the rim. If you’re looking for more sidewall support/damping from your insert, then they probably aren’t what you’re looking for. 

I've started using tannus tube inserts and tubes again just for the complete lack of upkeep required. Im an outlier 

haven't read all the replies but I'll put my input in. having broken a total of 6 reserve rims using CC pro i knew there was something up. turns out the pressure from "rim strikes" was transferred directly to the center bead; the thinnest spot of the rim and causing it to break over and over again, i had to buy another wheelset just to use the rims while the broken ones were in warranty process. ditched the rims and the inserts and changed my setup to Zipp/CB rims with newly released (at the time) Conti tires per recommendation of Wyn. they have that plastic strip on the tire bead on EN and DH tires which works great and protects pinch flats and rim breaks. must have! Schwalbe does the same now too

front wheel is Zipp, built it in oct 2020 and haven't touched it since (wow)

i broke one CB Enduro carbon rear racing big bear, rim was completely separated and tire didn't go flat. finished 3rd. i still have all my cushcore boxes, i was the biggest fan- trust me. but time goes on and i realized they just don't work for me.

take with a grain of salt! we're all on different bikes/tires/wheels/riding styles and terrain. i still recommend & even install cushcore regularly. just not on my bikes ha

edit- i did ride for tannus early/mid 2020 and they absolutely did not work. flat after flat i went through so many tires that season. eesh definitely take CC over Tannus, no offense to them. just simply didn't work for me

Well, it depends. 

Tires, Bike, am I racing? Do I need time to change tires and tire goo? Ugh. Sometimes there's no time for that when you have a wife and kid and job and house and life and stuff. Jus sayin

I'm getting older and have raced a ton. From Schwalbe Procore to Cushcore. They all work great. But you have an extra variable to your flat tire fix situation equation. If it should arise. And it will. 

These days? It's just DH casing Maxxis Meat with tubes. I still have inserts. But I'm not racing. And I want to keep it simple. 

just curious - were the reserve rims you broke carbon or alu?

this was long before the aluminum ones. and aluminum doesn't "break" like i mentioned.

i went through both versions, on two bikes, both v1 and v2 of 27.5's and 29's, 6 broken rims of 4 different versions, yeah it was really annoying especially after watching the danny mac launch vid, friggen snake oil... I've had my fair share with them. which was fun mid race season.

29"; both 591 and 596 ERD when they first changed them. I'd send a warranty out then get an updated version back- not knowing that then having to source spokes with a limited time frame was fun. ha.

second version held up much better but didn't have that stiffness like the original. although it measured 1mm thicker rim sidewall which was nice.

Out of curiosity are you destroying carbon wheels or alloy?  

I'm 225lbs geared up, Slow pro/expert DH rider.  I used to run the Cushcore's with DH Tires on various alloy dh wheels.  They would all inevitably break.  A few years ago I bit the bullet and got some Carbon rims and it has been a game changer for me in terms of not having to constantly tighten spokes and getting multiple seasons out of a wheelset.

Another aspect that would really piss me off was getting a sidewall cut and needing to put in a tube trailside.  You are stuck with a pool noodle covered in sealant that stains your gear and is a general mess that you can't just leave on the trail.