CushCore describe their product as Inner-Tire Suspension System®, it's an engineered foam insert that goes inside a mountain bike tyre and, together with the remaining air pocket inside the tyre, creates a kind of spring and damper system to add suspension.To most people the true value of CushCore is hard to determine because it's used as a preventative and you don’t know what would have happened to your rims or tire if it hadn’t been installed. Would that square edged rock have split the sidewall, or damaged your rim? But that is only one side of what they are all about.
I've been using CushCore for 18 months now, and I know for sure that what I get from using CushCore is a reduction in vibrations through the bars, and the softer and smoother feeling on the bike overall when pushing through rocky sections, especially when the rocks are all different in size and shape and consistent feel is hard to find. The CushCore just seems to soak up so much of that, keeps the bike on line and reduces my arm pump. It really feels like it is adding extra suspension. I initially noticed the small amount of extra weight, but soon got used to it. As far as reducing damage to the rims and tyres, my experience has proved CushCore to be worthwhile, and I have an example to share.
My most recent experience, which just proves the absolute value of CushCore, was at the National Gravity Enduro Championships at Fox Creek in October. For this race I ran my standard wheel/tyre combo of 29-inch E*Thirteen TRSr Carbon rims, and on the back wheel a Maxxis Minion DHR2 Double Down with a CushCore insert, running 27 psi.
On Stage 4 of the race I heard the unmistakable sound of a puncture and that hissing sound, and after about three to four revolutions of the wheel, the sound stopped. Upon finishing the stage I found sealant all up the seat tube as the puncture was between the centre knobs. I finished the race, three more stages and all the liaisons stages, without further issues.
On Stage 4 of the race I heard the unmistakable sound of a puncture and that hissing sound, and after about three to four revolutions of the wheel, the sound stopped. Upon finishing the stage I found sealant all up the seat tube as the puncture was between the centre knobs. I finished the race, three more stages and all the liaisons stages, without further issues.Upon finishing and checking my tyre, we found that the hole had sealed, the bead was still intact, but the tyre had lost 10 psi and I had raced the last three stages on 17 psi. I recall that it felt like the tyre was squirmy into corners and draggy when pedalling, but I was still able to continue riding to finish the race.
I have absolutely no doubt that if I did not have CushCore in my rim, there is no way I would have been able to ride as hard as I did, nor maybe even finish the race, with only 17 psi. A damaged tyre and/or damaged rim from the rocky track, one that had some pretty big jumps and step downs, probably would have been inevitable if not for the protection of CushCore, and from the side wall support and bead retention that CushCore also gave me.
The damage done to the CushCore after the weekend of racing is quite small (pictured below), which is great considering that included the three stages on 17 psi and the step down (as shown in the second photo) that wouldn’t have gone down well without the CushCore insert. The CushCore inserts were brand new for the champs so this is only from the one weekend. There are lots of these dents around the CushCore, but none of them have torn through, and the insert still feels solid.
I have CushCore inserts in all my bikes except my Dirt Jumper, and they will be staying in for as long as I ride bikes.