spokewrench
Active Member
- Region
- USA
After 150 miles, my Aventon Abound began making a brushing noise each time the right pedal passed 5 o-clock. Nothing rubbed when I hand cranked, and I saw that everything was clear when I removed the chain guard. I changed pedals and changed shoes. It didn’t help.
It was coming from the inside, where the bottom bracket was a torque sensor, and 5 o’clock was when the torque relaxed. If I extended the torque by using my foot to pull the right pedal through bottom dead center or by starting to push the left pedal before top dead center, there was no noise.
It was getting worse and I didn’t know much about bottom bracket torque sensors. If it had happened to me in 150 miles, and the model had been sold for a year or so, I figured it had happened to others. I contacted Support for advice.
When I registered, I used the same email address I’d used to order the bike. They had the purchase information on record but required me to provide it again. They said the purpose of registration was to streamline support requests. I used the same email address to contact Support, but they demanded all my purchase information again. They went further, demanding a clear photo of the serial number.
There was no reason for this except harassment. It entailed removing my mirror and horn and moving my gearshift, control pad, and display in order to turn the bike over to try to get a clear photo of what was an irregularity in the thick, glossy enamel.
They also demanded a photo of the problem. I submitted the serial number photo and reminded them that I’d said no cause for the noise was visible. They demanded a video. I said my snapshot camera would make videos but without audio. I said it would be dangerous to ride while using the camera with one hand, and the resulting video would reveal nothing.
They said they would have to see the sound to diagnose it, and if I would not submit a video, I would have to go to a dealer. The only dealer in 50 miles is accessible over 14 miles of narrow, busy highways. I don't have a car, and the bike wouldn't fit in a car anyway. It’s as if I’ve interfaced with a Communist Chinese AI bot who hasn’t learned that you can't see noise or that when you’re told nothing is visible, that means nothing will appear in a photo. It seems as if Aventon’s two-year warranty means that for two years their AI bot will tell you to go to hell.
That was Thursday. Friday, the noise was so loud that I felt like a steam locomotive, chuffing along. On the other side of a wide street, a man was walking his dog 100 yards ahead. He turned around and stood staring. Saturday there was an additional chuff, at 1 o’clock. That’s where the right bearing takes on its load, and 5 o’clock is where it’s released.
Sunday, the noises were miraculously gone. They were still gone Monday but back Tuesday. Now I understood. It’s a lube problem. A warm front had come in on Saturday. Sunday and Monday, the temperature had been around 60 for the first time in weeks. The right bearing takes twice the load of the left and, under a load, a ball bearing squeezes some lube away from the race. The lube is supposed to flow back fast enough to maintain a good film, but it was too viscous below 60 F, allowing the loaded side of the race to run dry. Just as the pressure was lifted, the dry balls would be loose enough to make noise.
The bottom bracket was at 40 when I got the bike out of the garage Wednesday. I kept warming it with a heat gun and taking a short test ride. When the temperature held at 62, the noise went away and didn’t return.
It was cold in December and January, and I rode every day with no noise. That means something has happened to the lube in the sealed bearings. If they lasted only two months, they must be of poor quality, like the tire that lasted a week.
Is it possible to fit an Aventon bottom bracket torque sensor with better bearings?
It was coming from the inside, where the bottom bracket was a torque sensor, and 5 o’clock was when the torque relaxed. If I extended the torque by using my foot to pull the right pedal through bottom dead center or by starting to push the left pedal before top dead center, there was no noise.
It was getting worse and I didn’t know much about bottom bracket torque sensors. If it had happened to me in 150 miles, and the model had been sold for a year or so, I figured it had happened to others. I contacted Support for advice.
When I registered, I used the same email address I’d used to order the bike. They had the purchase information on record but required me to provide it again. They said the purpose of registration was to streamline support requests. I used the same email address to contact Support, but they demanded all my purchase information again. They went further, demanding a clear photo of the serial number.
There was no reason for this except harassment. It entailed removing my mirror and horn and moving my gearshift, control pad, and display in order to turn the bike over to try to get a clear photo of what was an irregularity in the thick, glossy enamel.
They also demanded a photo of the problem. I submitted the serial number photo and reminded them that I’d said no cause for the noise was visible. They demanded a video. I said my snapshot camera would make videos but without audio. I said it would be dangerous to ride while using the camera with one hand, and the resulting video would reveal nothing.
They said they would have to see the sound to diagnose it, and if I would not submit a video, I would have to go to a dealer. The only dealer in 50 miles is accessible over 14 miles of narrow, busy highways. I don't have a car, and the bike wouldn't fit in a car anyway. It’s as if I’ve interfaced with a Communist Chinese AI bot who hasn’t learned that you can't see noise or that when you’re told nothing is visible, that means nothing will appear in a photo. It seems as if Aventon’s two-year warranty means that for two years their AI bot will tell you to go to hell.
That was Thursday. Friday, the noise was so loud that I felt like a steam locomotive, chuffing along. On the other side of a wide street, a man was walking his dog 100 yards ahead. He turned around and stood staring. Saturday there was an additional chuff, at 1 o’clock. That’s where the right bearing takes on its load, and 5 o’clock is where it’s released.
Sunday, the noises were miraculously gone. They were still gone Monday but back Tuesday. Now I understood. It’s a lube problem. A warm front had come in on Saturday. Sunday and Monday, the temperature had been around 60 for the first time in weeks. The right bearing takes twice the load of the left and, under a load, a ball bearing squeezes some lube away from the race. The lube is supposed to flow back fast enough to maintain a good film, but it was too viscous below 60 F, allowing the loaded side of the race to run dry. Just as the pressure was lifted, the dry balls would be loose enough to make noise.
The bottom bracket was at 40 when I got the bike out of the garage Wednesday. I kept warming it with a heat gun and taking a short test ride. When the temperature held at 62, the noise went away and didn’t return.
It was cold in December and January, and I rode every day with no noise. That means something has happened to the lube in the sealed bearings. If they lasted only two months, they must be of poor quality, like the tire that lasted a week.
Is it possible to fit an Aventon bottom bracket torque sensor with better bearings?
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