Gears shift when shock compresses

Dr_Tinkle
Dr_Tinkle Posts: 13
edited May 2013 in MTB workshop & tech
New bike Whyte T-129s.

Normal trail riding (not extreme)

When the rear shock compresses the gears shift to the next smallest ring on the rear cassette, sometimes fully, sometimes a half way shift.
Is this to do with the chain length, gear indexing or something different?
I just assumed that because it came straight from the shop things like this would be sorted.

Any advice would be most appreciated.

Comments

  • benpinnick
    benpinnick Posts: 4,148
    probably due to cable run. but then that normally causes upshift to a bigger cog not down. But worth checking the routing anyway.
    A Flock of Birds
    + some other bikes.
  • nicklouse
    nicklouse Posts: 50,675
    poor cable routing. too short cables. mucky cables with too much friction in them. cables moved in the cable ties causing the above.
    "Do not follow where the path may lead, Go instead where there is no path, and Leave a Trail."
    Parktools :?:SheldonBrown
  • Dr_Tinkle
    Dr_Tinkle Posts: 13
    Thanks Nicklouse.
    Assuming its routing or lengths then since bike brand new.
    Is it just trial and error on cable length or is there an ideal length for each section?
  • Chunkers1980
    Chunkers1980 Posts: 8,035
    Enough for all movement and smooth lines
  • nicklouse
    nicklouse Posts: 50,675
    Dr_Tinkle wrote:
    Thanks Nicklouse.
    Assuming its routing or lengths then since bike brand new.
    Is it just trial and error on cable length or is there an ideal length for each section?
    or they have moved and are being restrained by something.

    Pics would allow use to tell you where the issue is likely to be.
    "Do not follow where the path may lead, Go instead where there is no path, and Leave a Trail."
    Parktools :?:SheldonBrown
  • Dr_Tinkle
    Dr_Tinkle Posts: 13
    Thanks so much.
    Too late to go out there tonight so I'll inspect tomorrow and take pics if i can't solve it from this.
    Will deflate shock so I can simulate full movement and see what gives.
    Thanks for advice. Thanks also Chunkers.