• 02-16-2013
    4nbstd
    1 Attachment(s)
    Wheel Alignment on Sliding Drop Out.
    Does anybody have any tricks for aligning wheel axel in a sliding dropout after changing a cog?

    (picture not mine, just here to explain what I did)
    Attachment 772370

    I did matching turn for both side on the far left screw from the picture (i.e., 2 turn on right side, 2 turn on left side, and repeat) till what I heard is a good chain tension (about a half inch of play at the middle point between chain ring and cog). At the most, there's half a turn of screw variation between the two, and I'm fairly confident that it is straight, but I think I'm gonna stop by at the LBS just to make sure.
  • 02-16-2013
    SlowPokePete
    Does it look centered in the chain stays / seat stays?

    SPP
  • 02-16-2013
    bart bakker
    You can check if the wheels are aligned by putting a long straight object allongside the rims at a couple of inches of the floor. If the straight touches both rims at the front and rear you've got it right.
  • 02-16-2013
    4nbstd
    Quote:

    Originally Posted by SlowPokePete View Post
    Does it look centered in the chain stays / seat stays?

    SPP

    It looks centered, and rim seems to be in the center when I spun it with cable ties around seat stays (tip of the tie barely scraping the rim, tip moves while my wheel spins if it's out of true), but tire seems to wobble when spinning.
  • 02-16-2013
    Walt
    If it looks like it's pretty much centered, and your bike goes straight when you want it to, you are done, go for a ride.

    -Walt
  • 02-16-2013
    cstem
    Motion Pro Wheel Alignment Tool 08-0368 : Amazon.com : Automotive

    its for moto- but the principal is exactly the same. Put the hook end in on of the crank arm bolt heads, slide the adjustable portion to the rear axle center and secure, switch to other side and it should match up if straight. Easily makeable. I just look down the chainline from the back to front paying attention to gap between cog/sprocket and inside plate of chain at both ends.
  • 02-16-2013
    Nrs1Rider
    I usually just do the equal turns on both sides as you described and then just eye up the wheels position in the chain stays and the bolt position on the sliders to see if they look even.
  • 02-16-2013
    4nbstd
    Quote:

    Originally Posted by cstem View Post
    Motion Pro Wheel Alignment Tool 08-0368 : Amazon.com : Automotive

    its for moto- but the principal is exactly the same. Put the hook end in on of the crank arm bolt heads, slide the adjustable portion to the rear axle center and secure, switch to other side and it should match up if straight. Easily makeable. I just look down the chainline from the back to front paying attention to gap between cog/sprocket and inside plate of chain at both ends.

    I'm gonna measure the distance between one of the bolt on the slider and inside of chain/seat stays with a vernier caliper, and see if that'll remove my doubt.
  • 02-16-2013
    4nbstd
    Quote:

    Originally Posted by Walt View Post
    If it looks like it's pretty much centered, and your bike goes straight when you want it to, you are done, go for a ride.

    -Walt

    Still quite a bit of snow around here, I have at least another month of being OCD over little things. lol.
  • 02-16-2013
    febikes
    Quote:

    Originally Posted by 4nbstd View Post
    I'm gonna measure the distance between one of the bolt on the slider and inside of chain/seat stays with a vernier caliper, and see if that'll remove my doubt.

    If you measure anything measure the gap between the tire and the chainstay.

    But seriously just eyeball the tire gap and you are good to go. Basically you will be fine provide the tire has proper clearance for mud and dirt. In fact, the rocks on the last trail I was on seemed to be more then 2mm out of spec.
  • 02-17-2013
    fer83
    the easyest way to me is to look for chainring and cog alignement respective to the chain. I know that my chainline is correct so...
  • 02-17-2013
    cstem
    Wheel Alignment on Sliding Drop Out.
    Eyeball method is good and I use it and counting turns on adjusters after I have it all set up.

    The biggest reason to give a damn (besides chain derailing) is excess wear and tear. An in correct chain line places constant side load onto the chain, gears and bearings. I you or someone you know is breaking chains- I will almost guarantee they are running a slightly out if whack chainlne.

    A used chain can also throw you off with the eyeball method since the side play can make it hang straight. That is where the alignment tool comes in handy after resetting adjustment screws on dropouts.


    Sent from your Moms phone.
  • 02-17-2013
    4nbstd
    Quote:

    Originally Posted by cstem View Post

    The biggest reason to give a damn (besides chain derailing) is excess wear and tear. An in correct chain line places constant side load onto the chain, gears and bearings.

    Ya, uneven load on my hub is pretty much the only thing I'm actually worried about, as it won't be cheap to replace.

    I measured every single possible ways, and it seems it's on straight.
  • 02-17-2013
    fishcreek
    Quote:

    Originally Posted by 4nbstd View Post
    It looks centered, and rim seems to be in the center when I spun it with cable ties around seat stays (tip of the tie barely scraping the rim, tip moves while my wheel spins if it's out of true), but tire seems to wobble when spinning.

    tires will never be perfectly round. but if the wobble is caused by your wheel, its time to put it on the truing stand and check the vertical true..