A granule disabled my Abound!

spokewrench

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USA
I have ridden my Abound about 30 miles. I used it to get groceries in this afternoon. When I rolled it out an hour later, the back tire was flat. I took the wheel off, cleaned the tire, and found no evidence on the outside. In a case like that, I mark the tire at the valve on the chain side, and I mark the tube at the valve on the same side.

I found the puncture in the tube, but the casing felt smooth in that area. Matching the tube to the tire, I determined the exact spot and saw a bit of discoloration. Digging with my fingernail, I got out a granule that had been completely imbedded in the soft rubber. It had once been broken glass, but being run over countless times had worn it too smooth to prick my skin when I rolled it between my thumb and forefinger. It was like a grain of sand, but at 2.5 x 3.5mm, slightly bigger.

It reminds me of the time I had a flat from a 1/4 inch length of thin stick, not like a thorn, but fairly soft, almost like the stem of a leaf. What's wrong with ebike tires these days? In the days of the classic 26 x 1-3/8 tire, it took something like a nail to get through to the tube. One reason I bought the Abound was standard rims. The OEM tires are Innova. Schwalbe has more than one puncture-resistant tire that would fit.

An ebike flat can happen any time, and ebikes are harder than pushbikes to patch in the field. Pushing an ebike with a flat could be a drag and cause damage. Reinflation can usually make a bike rideable at least for a few minutes. I guess I'll start carrying a pump with a built-in gauge, whether it's manual or rechargeable.
 

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ya most of the time I got a flat I could not find it from the outside so the sealant would not work. tubeless is nice the thing is ejected now.
 
I ride $26 knobbies from Kenda or Giant. As long as the knobs are taller than 3/32", they roll right over junk like that glass fragment. Too thick to go through the knob, too tall to allow small glass or metal fragments to touch the thinner part. I get <1 flat a year with 2000 miles annual use. I use no sealant or liners, and standard $8 tubes. Slime sealant plugs up schrader valves if left alone for a year. I ride on road, although the knobs are useful for climbing at an angle the driveways the city+state have designed to have a 1 1/2" vertical ledge.
 
Thread count! (TPI or EPI) There's no sign of tearing, so the granule, 2.5 x 3.5mm, must have lodged between threads. That looks very bad. Schwalbe says the cheapest tires have 20 to 24 EPI. That would be one every 1 to 1.25mm. Tires with low counts are usually made with thick threads, so the spaces would be far smaller than 1mm. These Innova tires must have a very low count of thin threads. I guess somebody in authority at the Abound factory doesn't know tire specs. My trip meter keeps telling me how many trees I've saved, so there must be incompetence on the design team.

Putting the center stand on an 8 x 8 x 16 cement block was a great way to remove the back wheel... until a shove caused it to roll off the stand because I'd neglected to secure the front wheel with a bungee cord. I guess I could carry that 43 pound block in my pannier to be ready to patch a flat on the road. (Speaking of weight, the back wheel weighed 17 pounds. The tire, tube, rim, disk, and spokes are obviously quite light. That's a massive motor!)

These OEM tires can't be trusted. Schwalbe says 67 EPI is the best for low rolling resistance and high puncture protection. They don't make anything less than 50, and almost all include puncture protection belts.

For 3 years I've hated my 30 TPI Radrunner tires. I would have replaced them if I'd known of something better that would fit a rim of that width. Aventon has proved to me that there are even worse tires. I love my OEM Radmission tires. I think they're marked 60 TPI.
 
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I've tried Slime in six cases. Two were tubeless mower tires with slow leaks. It worked on one. The other four were bicycle inner tubes that were more porous than butyl tubes used to be. Slime didn't help. The Area 51 dealer was a Slime believer. Then he tested it against other products, including at least one puncture protection belt. The winner was Flat Out.
 
I did not know that about TPI. Good info.

I've also had slime clog up my shraders. You don't know when it works, but you do when it doesn't. I think it works more than it fails, but have seen the green liquid ooze out of a pinhole when I removed the tube. The holes was caused by the rim though. Tossed out some stuck valve cores, before I realized they clean up up in hot water. ||

I've heard Flat-out works nice.
 
I ordered a Schwalbe Pickup, designed for cargo ebikes. Most Schwalbe tires seem to have 67 EPI with a puncture-protection belt. The Pickup has two 67 EPI layers, to carry more weight besides resisting penetration. It weighs 2 pounds, which I'm sure is much more than the OEM tire. It's rated at 125 kg. It would have to carry more than that with a 250-pound rider and 143 on the rack and perhaps 2/3 of the weight of the unloaded bike. It's hard to believe the OEM tire is rated for what the Abound is rated to carry.

Modern Bike advertises it for $48, but they're out and I don't know if that includes shipping. Amazon is charging about $62 including tax. I haven't owned the Abound long enough to see if the tubes lose air inconveniently fast. I may end up installing Schwalbe low-porosity tubes.
 
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