Chris O

Hi All,

I have a Saris Fluid 2 indoor trainer with which I use a 700X23c Vittoria trainer tire inflated to 120 PSI. I noticed the steel cylinder that contacts the tire is developing severe wear patterns and pitting. Saris says this is due to slippage of the tire. They sent me a new yellow clutch knob that I installed and tighten it until it clicks (about 3 full turns after contact) indicating proper resistance. Also, I cleaned the tire and cylinder with isopropyl alcohol. I was hoping these two things would stop the tire slippage and wear of the cylinder. But I noticed the tire starting to get black again indicating more wear of the steel.

Funny thing is, this didn't happen at all last winter. The only difference this year is a brand new Vittoria trainer tire of the exact same make. Saris says some wear is normal, but my unit is not particularly high mileage, and as I mentioned, it only just started this year. Anybody have an idea of the problem or solution?

hayden52

Maybe you could try sanding the cylinder with some 320 grit sandpaper to get rid of the shinny smooth surface and give it a little bite.

Iride01 

Have you rode that tire outdoors any and maybe it has some grit embedded in the tire?

Do you check your tire pressure often? The click on the yellow knob is only good for that one day. Tires can loose pressure in a very short time depending on how thick the tube is and some other things.

My son has a cycleops trainer that appears to be pretty much the same model as what you have pictured. He also uses a Zaffiro Pro tire. The person he got the trainer from probably put over 10000 miles on it and the cylinder has very little wear.

TiHabanero

Assuming all things are constant from this year to last year except the tire, then it seems obvious to investigate the tire as it is the only thing that has changed.

caloso

I had a 20 year old Nashbar fluid trainer that had a noticeable trough worn into the cylinder. Never affected the performance of the trainer. It was loud and rusty and the knob broke off so I had to use a vise-grip to tighten up the skewer, but I never worried about the cylinder wear since it was several inches thick.

Chris O

It's a new trainer tire. Never used outside. I pump up the tire each time and set the tension knob each time. Seem to be doing everything right. Maybe Vittoria changed their compound?

Iride01 

Could it possibly be that overspray from something getting on the tire and/or drum? Maybe some Pledge furniture polish that is used on a nearby table or the ArmorAll that you might use to keep the tires and saddle looking nice?

Are there actual groves being worn in the drum or just mostly the black crud from aluminum oxide and something it's mixing with?

chaadster

Interesting case, and I’ll speculate that a reduction in tire pressure might reduce wear by transferring some of the contact force away from the tire-to-drum contact patch and into tire casing flex.


That said, I dunno what pressure the OP was using last year when this was not an issue, nor whether or not any possible change in tire contruction (incl. tread compound) could be at play here, either. However, if rubber resists wear by being springy, and the microstructure of the rubber is harder than the drum and thusly causing wear, it seems to follow that reducing the compression pressure on the contact patch by allowing the casing to deform more might help to reduce wear.

I’m neither a materials scientist nor an engineer, so shoot holes in that theory as needed…