EXN Grinding When Going Over Bumps

[Zalagator]

I have a question for anyone who is familiar with the original hallow bore EXN:

When I go over a decently sized bump, or drop off the edge of a curb, I feel/hear a grinding noise in my feet. If I didn't know any better, I would say that it is the bearings grinding under load. I don't jump the wheel, don't do stairs, etc., and when riding over flat ground it feels fine.

Is this a known thing? I only have about 500 miles on it, and haven't used it in wet conditions or anything. With gear I'm about 260 pounds, and run between 35-40 PSI.

I'm just trying to figure out what the grinding is, because it doesn't sound/feel right. The wheel has done this since my first ride when it was brand new.

Thanks for your help!

[EMA]

are you sure you are not referring to the sound of the motor when demanding power at low speed ?

[Zalagator]

I'm not exactly sure what you mean by motor sound, but there is a definite vibration/grinding feeling, so I don't believe so. This happens at low & high speeds, and is always connected with hitting a bump or dip. I'm now wondering if it might be a clearance issue with the tire, given that my wheel seems to also have a small bit of wobble when I spin it by hand. When the rain hits next week I think I'll tear into it and see what I can find. Thanks.

Mark

[EMA]

make a video of it

[Tony Shermax]

I just did a search for this exact sound to see if anyone else has it.

I know the sound you are meaning, it sounds like cogs skipping teeth, but wheel seems 100% after stopping to seeing if the wheel had any sound to it.

Going from footpath to grass with a 2 inch gap and 2inch drop I heard that exact sounds. Heard it again today when I went up the driveway and I got about an inch of air under the EXN HS.

[Tony Shermax]

On 9/15/2021 at 2:31 AM, Zalagator said:

I have a question for anyone who is familiar with the original hallow bore EXN:

When I go over a decently sized bump, or drop off the edge of a curb, I feel/hear a grinding noise in my feet. If I didn't know any better, I would say that it is the bearings grinding under load. I don't jump the wheel, don't do stairs, etc., and when riding over flat ground it feels fine.

Is this a known thing? I only have about 500 miles on it, and haven't used it in wet conditions or anything. With gear I'm about 260 pounds, and run between 35-40 PSI.

I'm just trying to figure out what the grinding is, because it doesn't sound/feel right. The wheel has done this since my first ride when it was brand new.

Thanks for your help!

Do you have EXN HT or HS