Inserts to prevent pinch flats?

I’ve long been against the idea of inserts. Mainly because I don’t need them.

A bit like 29″ wheels, eMTBs, 12sp drivetrain, full suspension frames and tyres with thick sidewalls.

So, my 12sp equipped, full suspension ebike now has tyres with thicker sidewalls. And as it turns out, I’m fairly fond of them. I prefer the feeling of a stiffer tyre at lower pressure. Not sure I could explain why but I do.

Trouble is to me, thicker sidewalls feel terrible a higher pressure and so I’ve gone low to maintain some control and grip.

Things like rain bars and random pointy rocks have lead to multiple rear tyres with multiple repair noodles stuffed through the sidewall around the bead which is becoming a bit of a problem.

I’m not riding particularly hard or fast. Just generally trying to enjoy myself. I don’t ride bike park or trail center stuff. It’s mainly ‘natural’ riding on bridleways and the occasional ‘accidental’ exploratory jaunt along things which aren’t bridleways in areas such as Surrey Hills, Peak District, Wales etc. If I happen across built trails on my way then I’ll happily ride them but I’m not hitting G out speeds on berms etc.

A lot of inserts seem to be quite volumous and the marketing nonsense blurb claims things like enhanced sidewall stability and ride damping qualities and whatnot. All I really want (I think) is something to help protect the tyre from pinching against the rim when I do something silly.

Does such a thing exist?

Cost and weight are both a factor.

Looking at Cushcore, the trail versions weigh 212g each. So having bought new wheels to save a bit of weight, I’d be spending £135 to make the wheelset just as heavy as it was before.

Firstly the cost is ridiculous and I’m not sure I want to add that much rotational weight. I know they have a huge following and I’m sure they have their uses but I don’t see them being suitable for me?

Anyway, are there any inserts around that don’t weigh a daft amount and just help protect the tyre from pinching? I like the look of the Tubolight SL but it looks like it’s been discontinued. Vittoria Airliner is probably the next best thing? I like the concept of the Schwalbe ProCore but that’s something trying to solve a problem that I don’t think I suffer from.

Happy with various previous version Vittoria Airliners. Suspect the new shaped one will be just as good

I stuck a Rimpact v2 in the rear wheel of my full sus beginning of last year, don’t think I’ve had a flat since then. Less pricey than the other options at ~£45 a wheel, but still pricey for a bit of fancy foam! Personally I can’t recall more than 1 front wheel flat in the last 10 years, so I’ve not needed one in the front wheel. Have since bought another Rimpact for my hardtail.

Rimpacts are half the price of Cushcore and do the same thing. They’ve saved me a fortune in tyres and rims.

Yes they change the ride feel, it’s like adding suspension to your tyres. I like it.

Yes they make the sidewalls more rigid making it much harder to burp a tyre.

I think a pair of them weighs around the same as one decent 29er innertube.

It sounds like you don’t need or want them so I wouldn’t bother.

Just go tubeless with a decent tyre and sealant? A good tyre at the right pressure will feel great. Thick sidewalls feel awful.

You could still get tougher tyres instead of inserts which could solve your issues, unless you’re already riding DH casing tyres?

I can’t say that I notice the supposed improved ride quality aspects of inserts but I guess it makes them sound better from a marketing perspective.

rimpact make riding far smoother, got them in all my bikes, including gravel.

a few grams of foam isnt gonna make much difference to a ebike weight, i cant tell on a 9-10kg gravel bike

that last pinch flat/ding i had was on some brand new dt swiss alu rims, i’d received the rimpact the day before but decided i didnt have the time to fit them and sods law was looking at my garmin went over a water bar and properly dinged them. :0( last time i had to dig out a tube

i tend to bunny hop (badly) water bars, easier on rims

Get Rimpact Pro inserts, they have virtually eliminated pinch flats for me.

You’ll be raving about them if you’re gettign a load now.

Rimpact original v1s on my trail bike. The v2 are a bit wider which I feared would make tyre fitting more difficult, so on my lite ebike I’ve just fitted Panzers. More difficult rim profile on these wheels but difficulty was about the same, so perhaps balanced out.

Trouble is to me, thicker sidewalls feel terrible a higher pressure and so I’ve gone low to maintain some control and grip.

Same. And at the lower pressure where they feel good, burping air and sealant. That’s without an insert, which I couldn’t manage to fit, and really was meant to be a net neutral weight exchange anyway by dropping the insert.

I think a pair of them weighs around the same as one decent 29er innertube

90g each for rimpact original 29er. As it happens I just weighed a 29er tube and it was 270g.

I use Panzers coz a big Pinkbike review said they were pretty good, light, cheap, and easier to install than most. Found that to be true, and I prefer the feel of less stiff sidewall tires at lower pressures with the insert. It stopped rim pinch snakebites on the tubeless set ups so yes, it will resolve your issues.

Hate: getting them into tires & onto rims, and even worse getting tires off again, has taken a lot of screaming frustration and thumbs like Geoff Capes. If I ever have a huge tire slashing issue on a trail I’m not sure I’d be able to resolve.  The way they turn any sealant into rolling stanimals inside the tire a bit of a pain.

Love: the traction they give, esp on the rear, at lower than normal pressures, the support they give to both tires at lower than normal pressures when leaning over in hard turns, that it removes snakebite risk.

EDIT: additional note – have thus far failed to be able to install in a kryptotal enduro casing on the rear of my eeb. after an hour of trying I sat on the floor of garage, sobbing, covered in sealant and trying to figure out how I would pull myself up with forearms and hands as useless as a t-rex.

have thus far failed to be able to install in a kryptotal enduro casing on the rear of my eeb. after an hour of trying I sat on the floor of garage, sobbing, covered in sealant and trying to figure out how I would pull myself up with forearms and hands as useless as a t-rex.

Haha, if you don’t have one of these, you can thank me later:

IceToolz DH Tyre Lever for Aluminium or Carbon Rims

I’ve got some large metal tyre levers which make the job slightly easier. Top tip is to wrap the ends in insulation tape to stop them gouging your rims.

I have 2 pairs of Rimpact Pros and 2 new bikes. Both pairs of Rimpacts are hanging on the garage wall because I’m not ready for the physical and psychological battle of fitting them. I do much prefer having them in there though. The ‘feel’ isn’t just marketing waffle. It’s like turning down the volume on trail chatter and I find it almost impossible to burp the tyres so I hit corners much harder.

One of mine needs to be converted to 27.5 to fit the new mullet. I’m going to try shortening it by cutting a chunk out and gluing it back together. It might save me £40 which is the cost of a new one.

I’m a fan of lighter tyres at lower pressures with inserts.

I used Cushcore because that’s what I tried first. Some people say that inserts can make the tyre feel dead through the high ramp up, but I don’t find that with Cushcore.

If I was buying again, I’d use the slightly lighter weight Cushcores.

Examining them whenever I change tyres is interesting because it shows just how many pinch flats they’ve prevented.

I actually find it easier to fit tyres with Cushore than without because they tend to inflate straight away.

“I’ve long been against the idea of inserts. Mainly because I don’t need them.”

Sounds like you do though! Get some Rimpacts – the normal ones, not pro will be fine. They’re light and not too horrible to fit. I recommend buying a Cushcore Bead Dropper tyre lever to help fit them – I’ve got pretty strong hands and it still makes a useful difference in easing the job.

” I’m not ready for the physical and psychological battle of fitting them”

Buy a Bead Dropper! If you use that and make sure you push the bead right under the insert as you work your way around you’ll find it’s really not that hard.

Examining them whenever I change tyres is interesting because it shows just how many pinch flats they’ve prevented.

Same. One pair of my Rimpacts went to Malaga for a week and when I came back it looked like I’d attacked it with a knife.

When I was there in 2012 with DH tyres I remember fixing lots of punctures and truing my wheels every night.

I run a pair because the last tyre I destroyed was on the front. This was on the sharp edge of a tiny rock on a fairly tame trail. For the value of the increased protection the weight is meaningless.

We’ve got a couple of bikes running Vittoria Airliners in the rear for pinch flat protection and they work great (fixed the issues we were having and been good for the last year). Just running the small xc size even in 2.5″ tyres so they are easy to fit and work with standard tubeless valves. Got them for £20 at the time but no offers at the moment, and the new version is a different shape. Amazon seems to do some with very similar cross section for not much money. Shape is like this:

Vittoria Air-Liner Mountain Bike Tubeless Tyre Insert

Buy a Bead Dropper! If you use that and make sure you push the bead right under the insert as you work your way around you’ll find it’s really not that hard.

dont use gorilla tape as rim tape with rimpact insert as the tyre glues itself to teh tape and its a right bastard to get the tyre off. i ended up having to cut the tyre to get the insert out to allow me to get the tyre off!

The original Vittoria Airliners do exactly what you want. I’m not convinced the new version will work as well. There’s ZZTO copies of the originals on ali express that are cheap enough to be worth trying.

I ran one on the rear and still got pinch flats which is much more annoying trail side than when you don’t have an insert in.

Went back to heavy duty tyres and 30psi. Lasted well until recently when I must have landed on a an edge. Won’t rush back to inserts.

There’s no way I’d run 30psi in a DH tyre. It must bounce down the street like a skateboard. Maybe for commuting or canal paths but nothing else.

I run tannus armour insert and tube on my ebike rear wheel.  Been faultless for 3 years now.

There’s no way I’d run 30psi in a DH tyre. It must bounce down the street like a skateboard. Maybe for commuting or canal paths but nothing else.

Not at all. I’m putting 115kg through it and riding fairly rocky tracks. I’ve never liked less than 26 anyway, but I certainly don’t suffer from lack of traction.

Have some Nukeproof ones in a set of 27.5 wheels and xc tyres. Have also used the old barbieri (pipe lagging) in cx tyres and wheels for racing. Have been pleased with both although getting the cx inserts and then the 33c vittoria wets  on was an absolute bastard. If I were using that tyre/wheel combo for road/bridleslaying I’d not bother with the inserts and just use higher pressure

Thanks all. Some good points raised here.

Just to clarify a few things, I’m already setup tubeless using Stans. I’ve always ridden Maxxis EXO but for the last ~6 months have been on a Bontrager SE6/5 combo which are definitely stiffer in the sidewall. Similar to an EXO+ but possibly a little stiffer.

They feel really good and I prefer the more damped feeling  vs the lighter tyres which always feel a bit pingy. I used to like that feeling but now in on the fence.

I’m only looking at the rear wheel as I’ve never had a problem with pinching the front, even at 15psi.

(did I mention I don’t ride hard…)

I guess with an effective insert, I might get away with lighter tyres and still manage to achieve a more damped feeling by dropping the pressure and relying on the insert to keep the tyre in one piece.

That’s kind of not what I had in mind though. I see the idea of an insert to be a bit like a seat belt in a car. It’s there for emergencies when I would otherwise be pitching the tyre rather than rely on it entirely.

I did think about heavier still carcasses (Maxxis DD or Schwalbe Gravity) but it’s a huge jump in woeght and I think it’s overkill for my riding. I try and squeeze as many miles in as possible and I’m not pinching the tyres every ride. But, it’s been happening fairly often recently where I’ve been out riding rocky terrain.

If I put more air in the tyre to stop it pinching, the handling suffers. If I run the tyres at a sweep spot for grip and compliance, I’ll ding the rims and pinch the tyres which is why I thought an insert would help.

There’s a few ‘flat’ looking inserts kicking around like  Rockstop  and  Slicy Smooth. They seem like they’re designed to do what I want but I can’t help thinking that they would move around in the tyre and end up twisting.

I’m liking the look of the Tannus Armour as a sort of in-between a full insert and a flat one. The Vittoria XC looks good too but I think it might be a bit undersized in a 2.4/2.5 tyre. Maybe that’ll make it easier to fit!

I like the look of the Rimpact (Original v2). Similar shape to the XC Airliner but made for bigger tyres so possibly the sweet spot for me. For some reason, they hadn’t show up while I was searching around. The Panzer look pretty similar in terms of shape and price so they’re in the running as well.

Seeing as its a Friday, I might allow wine to make a decision for me later.

To give an idea of what the original Rimpacts can do, I dented the (very soft) rear rim on my Levo within a few weeks of getting it, and that was riding on muddy rooty trails, so slower and almost no rocks. I then put the Rimpacts in and got through literally a few years without adding any obvious rim dents, so plenty of miles on faster rougher trails, and that includes swapping those wheels onto my hardtail so the rear took quite a few hard hits.

I’d take the very marginal weight difference of the Rimpact Pro.

I’ve killed a rim with the original Rimpact in, but don’t think I’ve even dented one with a Pro. They last much better too, as the denser cap layer is less prone to tearing.

If you just want pinch protection and easy fit / removal then adding an xc size old shape Vittoria (copy) works great in a 2.5 tyre for very little money. You don’t get the same tyre support benefits of some other systems, but you also don’t have the cost and fitting hassles.

I have used the cheapo ones from ebay on my old bike but since switching to a 29er I haven’t bothered. I’m not saying that the wheel diameter makes the difference. But they roll for me over more obstacles more easily. Might be a coincidence but on Wednesdays night ride, only the 27.5 wheel guys got punctures.

The real reason is I now use the DH versions of the MM & BB tyres. Not by design but by chance as they were all I could get my hands on when I bought them and I felt sticking an insert in was a bit over kill.

You could just go to a tougher rear tyre – looks like the SE5 is quite light – found a review that suggests the 29×2.6” one is barely over 1kg.

I’m generally liking the enduro casing Contis which are quoted at 1125g but are probably more like 1200g. Not as heavy as a full on DH tyre and I’m pedalling them round quite happily on a Transition Sentinel that weighs 34-35lbs depending on which shock I’m running.

I have run the original rimpact in lighter tyres but I find them a bit annoying. The valves seem to clog up quite quickly with sealant and then it all has to come apart to sort it out (it’s not just the unscrewable core – but the side facing holes in the rimpact valves).

That said – they may well do what you need them to.

The Panzer look pretty similar in terms of shape and price so they’re in the running as well.

First ride on these today, I’m not sure I can recommend them for anyone looking for improved tyre hold on the rim to prevent burps.

Wild Enduro Front normal version, ran one for ages on my trail bike with a Rimpact original v1. It has the most supple sidewall I’ve had to feel by and on an MTB. Ran at 20psi, no burps. Same tyre now with Panzers, and on a tighter fitting rim, and on my light eMTB (4kg heavier than my trail bike) it’s burping little bits of sealant at 23psi.

I can imagine the lack of a flat base (https://www.pinkbike.com/photo/24968667/) means it doesn’t hold the bead in place as good as Rimpact does.

Rimpact fan here too, had them in the rears on both the hardtail and full suss for over a year with no dramas yet (got fed up of splitting sidewalls on otherwise good tyres) Bit of a faff to fit though!

I just cut up one of my Rimpact Pros to try to shorten it. I’ve made a right mess!

First attempted to glue it with 2 pack epoxy Gorilla glue because I already had it in. It was impossible to hold it still in my hands without it sliding around and coming apart. Eventually the glue got too tacky and it was never going to work.

Second plan is this …

I’m leaving it overnight so if it works I’ll let you know tomorrow. If not I’ll be spending 40 quid on a new one.

I fitted the 29er to the front no problem. It actually went on really easily.

@sharkattack I once bought some factory seconds Rimpact, and one turned out to be a 26″ with a piece glued in to make it 29″. Turns out it wasn’t meant for sale and I got a refund. It’s held for over two years.

Might be worth asking them what they use, or what common alternatives they recommend.

I am kind of curious how they do it but I don’t want to turn this into a major operation. Basically I had a spare 29er and thought it was worth a try.

If it doesn’t work I’ll suck it up and buy one. If it gets me through 2 days of BPW next weekend I’ll be very happy.

What glue did you use on the cable tied attempt?

I’d have thought something to bond the ends together rather than stick them. Something which melts the foam and creates a single piece. Bit like the glue for airfix but for foam instead.

What that is though, I have no idea.

What glue did you use on the cable tied attempt?

Same again as it’s all I’ve got apart from tiny tubes of super glue.

My theory was that the first attempt at least built up a coating on the ends and prevents the second lot from being absorbed so much. It might be a better surface to for sticking together.

I’ll check on it tomorrow. Don’t let the suspense keep you awake tonight.

It’ll probably be fine as you’ve got the cable ties as well – normally you’d want the glue to be as flexible as the foam. I did it with contact adhesive, evostik, as advised on here – cover each end, let it dry fully, then add another coat and press them together once tacky as usual with evostik. No cable ties and still good some months on.

I think it’s worked pretty well. On my test piece, with no cable ties, I tried to pull it apart and the foam failed before the glue.

It survived installation. It’s inflated and holding air, even though the tyre has 3 plugs in it.

I’m not riding it because I’m full of cold and absolutely knackered. If it lasts a few month it was worth the effort.

Extra mass and power of an e-bike leading to pinch flats in spite of tougher tyres? This is why e-bikes cause more trail erosion. I know it’ll likely lead to a flaming, but haven’t seen anything to lead me to question the basic physics behind this. The increased erosion on trails around here (N Lakes) since e-bikes took off is also clear. I guess people want more fun and the consequences have to be accepted.