can't pedal backwards on Saris M3 Direct Driver Trainer

First time using trainer. And without the bike, i can spin the casette backwards no problem. but once i put the bike on, i can't pedal backwards, the chain just lose tension pedaling backwards... is this normal? or something is wrong.

I am using a XDR casette with SRAM FORCE AXS 12Speed Casette. (my bike came with RED AXS 12SPeed). They are exact same casette size 10-28.

Comments

  • tyw214
    tyw214 Posts: 52
    oh, i also forgot to mention, when i am not pedaling, the cranks are very stiff to turn with my hand, and it gets easier as i go faster. is this normal....?
  • tyw214
    tyw214 Posts: 52
    Ah forgot again, Coasting seems to work. When i stopped pedaling i can still hear the hub spinning rapidly.
  • me-109
    me-109 Posts: 1,915
    Sounds like the outer end of the cassette might be dragging on the inside of the dropout. Loosen off the QR a little, just opening the lever for example, and see if it is any easier to turn. Might give an indication of where the issue lies.
  • tyw214
    tyw214 Posts: 52
    me-109 said:

    Sounds like the outer end of the cassette might be dragging on the inside of the dropout. Loosen off the QR a little, just opening the lever for example, and see if it is any easier to turn. Might give an indication of where the issue lies.

    I am using thru axle, but you are right, once i losen up the thru axle, i can pedal backwards without problem... but the thru axle right now is quite lose, because there is a little bit of side-way wobbling if i shake my bike left and right... that's not good right.
  • me-109
    me-109 Posts: 1,915
    If you haven't already you might want to check there really aren't any spacers behind the cassette from the factory. I presume the are like a microspline greeting so can't imagine they would have, unlike a regular 11s one might. Bit of a bridge but you could try squeezing in a large washer (diameter, not thickness) over the outboard end of the freehub to space it off the frame.
  • DeVlaeminck
    DeVlaeminck Posts: 8,709
    There is an issue with a top hat shaped washer that can crack on these - take cassette off and check.
    [Castle Donington Ladies FC - going up in '22]
  • DeVlaeminck
    DeVlaeminck Posts: 8,709
    Should add no it's not normal - I've got the same trainer and I can back pedal fine.
    [Castle Donington Ladies FC - going up in '22]