Hi, I have a 2023 ibex 800. I'm experiencing a bucking and surging when I downshift.

I noticed this mostly when I'm downshifting to third gear or second approaching a corner.

Yesterday the rear wheel locked up when I was about to corner due to a little bit of sand in the roadway when it buck and surged.  What's the fix?

This is getting dangerous!!

Hi, I am in South Carolina.
I have a 2023 ibex 800.
Don't know if anybody else is experiencing it, but my bike likes to buck and surge when I downshift, especially into second or third gear approaching a corner, this downshift is to slow down for the corner.
I've noticed when I downshift about 20% of the time the bike likes to Buck/Surge forward.

When I slow with a downshift the bike Bucks and Surges, then repeat this several times. Then returns to normal slowing with the downshift.

Was trying to slow to take a corner yesterday and experience this going into second gear the rear end locked up due to some sand on the roadway.

Has anybody else experience this and what's the fix?

Finding it to be super dangerous!!