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Meta 55 - RH Crank close to swing arm

dmortondmorton Posts: 244
edited February 2013 in MTB workshop & tech
I built up a 2010 Meta 55 frame last year. I have a problem that my right hand crank is very close to the swing arm. This causes my heel to occasionally clip the swing arm. I've found that I'm pushing my heel out to avoid this, that in turn twists my knee and after a while starts to ache. I think it's straining one ligament.

I don't get this issue with my other bike.

The cranks are Raceface Ride.

Here's a pic:

8453246644_317bb6e295_z.jpg

The crank has 1mm spacers that can be swapped side to side to adjust the chain line. What should the chain line be on this frame, anyone know?

Any other ideas? Shorter Crank arms?

Posts

  • The RookieThe Rookie Posts: 27,802
    Looking at that pedal position you must be cycling toe out to get your heel anywhere near the swing arm....so perhaps longer term you are better off training yourself to do that, it may hurt for a while but longer term will be of benefit (the son had this problem and was told by the doc to cycle to train his foot to put the toes forward, walking doesn't help as it's easy to forget to do it).
    Current steed - Whyte T129, 2013 frame, mongrel Revelations, Giant dropper, Stans S1 wheelset. 12, Magura Trail Sport brakes, 1x11. 12.8Kg
  • nicklousenicklouse Posts: 50,675 Lives Here
    looks normal to me.

    chain line is as should be with what you say.

    the only thing you can do other than changing the way you ride is to measure the distance between the Arms and find some with a greater distance which is not that likely.

    shorter cranks will not help.

    and clipping the swing arm is quite normal on many bikes.
    "Do not follow where the path may lead, Go instead where there is no path, and Leave a Trail."
    Parktools :?:SheldonBrown
  • EH_RobEH_Rob Posts: 1,134
    Yup, the same thing happens to me with my bike (Santa Cruz Nomad). I use flats though, so when it happens it just means my foot position is off.
  • dmortondmorton Posts: 244
    Thanks for the replies guys

    If I was cycling toe out then I'd also scrub my cranks too? I don't scrub them. Also I only tend to catch the swing arm when going through twisty more technical stuff and I'm shifting weight about on the bike. However will make a mental note to check on where my feet are next time I'm out. Or get someone else to look, although it will be at night!

    For a sanity check, I've just measured (with a caliper) the back wheel rim to inside crank arm distance. Did this in several place on rim to account for true-ness. There is about 1-2mm difference between LH and RH cranks to each side of the rim. LH is slightly further out but I don't think 1-2mm is significant. Seems that I put the bike together correctly and it is a bike fit or technique problem

    I did think of another way my knee is being twisted and that is my foot is rolling over slightly and my knee is outward off it, looking from above. I've not adjusted the pedal clip tightness in a while, maybe that would help keep it flat

    There's also saddle height and position too to play around with....I seen that saddle height and knee pain are linked
  • EH_RobEH_Rob Posts: 1,134
    dmorton wrote:
    I seen that saddle height and knee pain are linked

    If I were you I'd use that excuse to get a Reverb
  • nicklousenicklouse Posts: 50,675 Lives Here
    EH_Rob wrote:
    dmorton wrote:
    I seen that saddle height and knee pain are linked

    If I were you I'd use that excuse to get a Reverb
    but that will not fix it.

    you still need to get the hight right.
    "Do not follow where the path may lead, Go instead where there is no path, and Leave a Trail."
    Parktools :?:SheldonBrown
  • EH_RobEH_Rob Posts: 1,134
    I know, its easier to change it though innit.

    I only said it as I'm looking for an excuse to buy one.
  • The RookieThe Rookie Posts: 27,802
    dmorton wrote:
    If I was cycling toe out then I'd also scrub my cranks too?
    No, if you look at your photo, an angle that would catch the swing arm wouldn't catch the cranks.

    If the cranks are offset to the left by 1-2mm I'd be inclined to swap a 1mm spacer over if that is possible.
    Current steed - Whyte T129, 2013 frame, mongrel Revelations, Giant dropper, Stans S1 wheelset. 12, Magura Trail Sport brakes, 1x11. 12.8Kg
  • dmortondmorton Posts: 244
    No, if you look at your photo, an angle that would catch the swing arm wouldn't catch the cranks.

    My heel would catch the cranks if they were 180 deg of where they are in the picture and I was toe-ing out/heel in. That's what I was thinking.
  • HuckfinnHuckfinn Posts: 142
    Is this not a combination of pedaling style and bike design?
  • dmortondmorton Posts: 244
    Went for a ride last night and think I have this sussed! The crank distance from frame seems to be a red herring.

    Seems I'm not a duck and I naturally position my feet straight/slight heel out.

    I tweaked the saddle position, moved it forward on the rails and slight up in height. No stretching of my knee occurred. However the interface between my right shoe and pedal is not quite right. Doesn't feel like I'm clipped all the way in, my foot rolls over slightly. The left one clips in flat. I think that this exaggerated the effect of the incorrect saddle height and caused the pain in my knee.

    The pedals on my other bike where I didn't have a problem are the Shimano ones without the cage. Maybe the cage is interfering with the ridges on the bottom of my shoe.
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