How do I adjust chain/rear wheel alignment?

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  • There are hash marks on either side of the rear wheel that are supposed to help you align it. The hash marks (on all bikes) are notoriously off. Some may be 2 or more marks off. The correct way to align the rear (for those who haven't trained their eye) is to measure from the center of the swingarm pivot point (has a chrome cap), to the center of the rear axle on both sides. Be picky to within 1mm difference.
This is the same as riding a pedal bike with the dérailleur not adjusted correctly. The chain is causing lots of friction and constantly tries to jump the sprocket. Annoying on a bicycle, it can easily cause one to be asphalt surfing on a motorcycle.
  • Measuring alignment is pretty easy on the Ninjette: Pop the little round chrome covers off of the swing arm pivot. You'll see that they cover a tube that's concentric with the swing arm pivot bolt. Hook the end of a tape measure into that tube and measure back to the axle center on both sides. Adjust until that measurement is equal on both sides.
After you get that measurement correct, check your chain slack. If that is out of spec, all you need to do is turn both of the adjusters the same amount (1/4 turn, 1/2 turn, etc...) That way you don't have to worry about your alignment getting off again.
  • An inexpensive alignment tool is the Motion Pro Chain Alignment Tool. It clamps to the sprocket and provides a straight bar with which to judge how straight the chain is from the rear sprocket (because "Aligned" is just the chain having a straight run from the rear sprocket to the front sprocket.)
  • Once you have done this: If the alignment marks were out of sync from each other, measure the difference and write it down somewhere. Next time you need to do something to the rear wheel you won't need to go through all these steps again.

Is there a tool for doing this?

This one is cheap, simple, and reliable.

Get a length of steel rod or all-thread (steel rod that's threaded) with one end bent to 90 degrees and a zip-tie on the other.


Put the bent end on the center of the swingarm pivot and move the ziptie to the center of the axle. When the distance is the same (you don't need to move the ziptie for either side) you have an aligned wheel and chain.

Is there a tool for doing this? 2

Of course there is a tool. And with this one, you get the added double satisfaction of being able to make it yourself and of it being cheap. This shouldn't really be necessary, but if you can't get the hang of the tape measure method, it's something you can try. This performs the same function as tools you can get from Muzzys and Race Tools.

Materials (all available from your local home improvement store for under $10):

  • (1) 1/2" EMT Conduit (sold in 10ft sections)
  • (2) 1/2"-1" Zinc Ground Clamps
  • (2) 1/4 - 20x4 Hangar bolts (pick ones with a pointed end)
  • (2) Nuts for the 1/4 hangar bolts
  • (2) 5/8" Hole plugs - Nylon (these are optional- they just look nice)


  • Phillips Screwdriver
  • Tubing cutter



1. Use the tubing cutter to cut your conduit to length. This one is 39 inches, but that's not a hard & fast number.

2. Set the tubing aside and remove the center screw from both ground clamps.


3. Take the 1/4" nuts and screw one onto each of the hangar bolts.


4. Screw the hangar bolt all the way into the ground clamp, then tighten the nut down (this locks the hangar bolt in place)


5. Secure both of the modified ground clamps onto the conduit. Place one at the end of the conduit and tighten with your screwdriver. Tighten the other by hand. It will be adjustable so that it can slide up and down the tubing.


6. If you've opted for the extra fancy version, insert the nylon hole plugs into each end of the conduit.


7. Your tool should look like this:


8. You will now be able to measure from the swing arm pivot (under that shiny chrome cap) to the axle bolt center. To use the tool: Place the fixed hangar bolt onto the center of the rear axle. Use your hand on the adjustable hangar bolt to tighten/loosen the slide as needed (see picture) to the swing arm pivot.


9. When both sides measure the same, your wheel is in alignment.