Rear Tire Alignment / Chain Tension

[fyl1982]

So, I replaced my rear tire and noticed... before I took the wheel off, the markers for the rear tire were off by about a full mark. I intended to correct this when putting on the new tire but I have a problem. The bar that holds the brake hub assembly is VERY close to my tire. Between tensioning the chain properly and aligning the rear tire to the markers, if I do that the tire will rub against this bar.

Here is a diagram I threw together in MS Paint...

So with the chain at proper tension I am about 5 and a half to 6 marks back on the chain side. On the brake side, about 4 and a half to 5 marks back before I get to within 1mm of the tire hitting that bar.

Is the chain too stretched out? Frame bent? Tire too wide?

This bike is in pretty good condition. Any help or advice would be appreciated. Thanks!!!

 

[jd750ace]

The marks are not accurate. If you drop a plumb bob from the swingarm pivot on both sides of the bike with it on the center stand, mark those spots on the ground, then drop one off each end of the rear axle and measure from the axle mark to the corresponding pivot mark, then you will know if you are truly aligned. The plate index marks are very often inaccurate.

 

[5twins]

What size tire have you mounted? A 130 is the standard Special size but one manufacturer's "130" can be different than anothers. Is your brake torque arm "dimpled"? The Special torque arm had a depression in the side specifically for tire clearance .....

If yours has no "dimple", it may be from a Standard. Make sure it's mounted correctly as well with the offset towards the front.

 

[XSLeo]

In my experence the mark on the swingarm are very accurate. If you want to check them there is a much easdier way than described by jd750ace. Just use a tape measure, hook the end over the grease zerk on the swing arm pivot bolt, measure from there back to the center of the rear axle. Do this on each side. Set the axle so the measurements are the same. Now look at the adjusters. How close are they. Pretty close I bet.
If you do this then adjust them evenly as you set the chain tension too about 5/8 to 3/4 inch play while the bike sets on the tires with you on the bike as you are riding.
If your tire is still a bit close you can bend the brace just enough to clear.
Another thing, on the front end of the brace is it in between the two sides of the bracket or on the inside of the bracket, Maybe even in with the front to the rear?
Leo