Too much torque on axle?

[witek]

My chain was loose a couple of days ago, so I tightened it up and all was well, everything was equal, everything was balanced. So I tighten up the rear axle and replace the cotter pin. Take it for a test drive and there's a hissing. Sounds like something is rubbing at the rear wheel. I quickly turn around and head back home to investigate. Both sides of the axle are on the same notch, and everything is equal. I re-check the alignment and try again. Same thing.

I might be wrong, but I've come to the conclusion on the third try that the axle might be too tight, after all the wheel moves much more freely when the axle is loosened up. So I have a question, how would I know how tight to tighten the axle without having a torque wrench with a readout? that or what else am I forgetting?

The numbers by the way are: Rear axle nut - Normal nut with cotter pin (US models)   50 - 80 Nm  36.0 - 58.0 ft-lb

[bassman]

I overtightened my first chain way too much.  When I took the bike out after overtightening there was a sort of intermittent 'swishing' which was probably the chain rubbing on the sprockets.  Eventually the chain failed (after several months of the chain being set correctly - the damage had been done!).  Make sure you are not setting too little slack.  Slack should be between 20mm to 30mm (which translates to an overall degree of play of 30mm to 40mm when measuring from the bottom surface of the chain to the top surface of the chain).  What I mean by this is that when the chain is just hanging, the underside of the chain is at 0mm.  When you lift the chain with your finger, the top surface of the chain should deflect up no more than 40mm from that 0mm position.  The mistake I used to make was to measure that overall deflection as 20mm to 30mm.  This meant that I was adjusting the chain to just 10mm to 20mm freeplay when considering the measurement from the centre of the chain.  10mm to 20mm is way too tight, and I'm sure this cooked my chain which eventually failed after I started adjusting it correctly.  And , of course, make quite sure the rear wheel is not crooked.  Don't rely on the visual adjusters - they're next to useless!  I measure the length of the adjuster thread sticking out of the end of the swingarm.  Not a perfect solution - but a lot more accurrate than those adjusters!

Bassman

[witek]

check again, and still have the same problem. This is frustrating.

[bassman]

Could it be your rear brake?  When you tightened the chain you moved the wheel backwards a mm or so.  Even that short distance changes how the brake pads are bedded against the rear disc.  You might have crud that has built up on the brake pads, and the crud is rubbing against the disc, possibly causing the 'swishing' sound.  I had that exact problem after I had pulled and replaced the forks.  Even though the front wheel doesn't move backwards and forwards like the rear, when I replaced the front wheel it caused the crud that had built up on the (quite new) brake pads to cause an intermittent 'swish' when I pushed the bike by hand.  I cured it by taking the pads off and tidying the crud off the edges of the pads with a file.  Fixed!!!  I was really worried that something was wrong with the way I had re-installed the front wheel.  But i hadn't done anything wrong, it was just a build up of crud that I hadn't seen!

bassman

[witek]

I had thought of that, but didn't have time to check it. I was actually going to try that exact method tomorrow.
Let's just hope that rain that is coming isn't going to last through to tomorrow.

[bassman]

Any luck with sorting it yet?

bassman