Freewheel / Casette Wobble

[GoatBeard]

The threaded bolt in the middle spins if I undo the nut on the opposite side. The whole thing slides out. There's some wobble on the casette so I'm hoping to tighten it.

 

[DCLane]

If you're undoing the threaded bolt that's the axle, not the cassette. Depending on the bearing type they may fall out everywhere.

You need a chain whip and a cassette lockring tool. Yours is a SRAM one, so a Shimano/SRAM one will fit. Have a look at: https://www.parktool.com/blog/repair-help/cassette-removal-and-installation

 

[Ajax Bay]

Is the lockring of the cassette tight? Can you 'wobble' the sprockets around (by hand)? If you can, you likely have freehub/cassette speed mismatch and a spacer is required. If no 'hand wobble' the issue is the bearing adjustment (no need to take cassette off but would normally do so).
What is the make/model of hub?

 

[GoatBeard]

Is the lockring of the cassette tight? Can you 'wobble' the sprockets around (by hand)? If you can, you likely have freehub/cassette speed mismatch and a spacer is required. If no 'hand wobble' the issue is the bearing adjustment (no need to take cassette off but would normally do so).
What is the make/model of hub?

I think it's possibly loose but I've ordered a chain whip so I'm going to see if I can get it tightened up. Unfortunately the whole setup is that lovely, murky grey area between BSO and 'Bike' - hello Carrera Subway. Might just ditch the no-name wheelset for something lighter and brighter. Would cost the value of the bike but ah well!

 

[figbat]

I think it's possibly loose but I've ordered a chain whip so I'm going to see if I can get it tightened up. Unfortunately the whole setup is that lovely, murky grey area between BSO and 'Bike' - hello Carrera Subway. Might just ditch the no-name wheelset for something lighter and brighter. Would cost the value of the bike but ah well!

To be clear, you don't need a chain whip to tighten it - you need the cassette lockring tool. something like this:

You need a chain whip if you want to undo the lockring - the chain whip holds the cassette still whilst you undo the lockring with the above tool.

 

[GoatBeard]

Just realized my rear mech is good up to 8 speed. My casette is a SRAM 7 speed! No wonder I felt a pretty massive jump between some gears. I think SRAM casettes are great though, any suggestions on ones compatible with the TX?

 

[Ajax Bay]

I think it's possibly loose

Think? Possibly? Commit yourself. Or you'll end up fixing (waiting for tools to fix) the wrong thing.

 

[Ajax Bay]

What shifters?

 

[DRM]

Sounds like you have Shimano Tourney 7 speed, so you will need an 8 speed shifter, and an 8 speed freewheel, or cassette depending on what’s fitted, if not an 8 speed cassette and a free hub type wheel as well, in all honesty it’s not worth the time and expense, you might as well go for at least a ten or 11 speed setup if going to do the 7 to 8 speed conversion

 

[DRM]

The cassette needs to be secured very tightly, 40nm iirc so you may need at least a strong arm bar to tighten it, but better with a torque wrench

 

[Ajax Bay]

40Nm (marked on lockring) is 20kg force with a 12" spanner (effective lever 8"). "Strong arm bar" definitely not required. A 70kg person will push about 20kg with one arm when doing a press-up (offered for calibration purposes).

 

[Ajax Bay]

an 8 speed freewheel

No such thing (sold) as an 8 speed freewheel.
Also any suggestions are complete guesses until more information is shared.
All we know (I think) is that the RD is marked Tourney TX and that the OP has a 7sp SRAM cassette (which of course is entirely compatible with the Tourney TX RD).

 

[GoatBeard]

It's only a cheap semi BSO bike (old Subway) so taking it up to 10 or 11 speed is a bit OTT. Just looking for a cheap and cheerful run about. I had 8 speed on a Claris roadie and got good results with a small range. Was thinking of getting second hand bits to do the subway up you know a used 8 speed grip shifter (got 7 speed) and a £15 SRAM casette. 13-26 would be very sweet.

 

[ColinJ]

40Nm (marked on lockring) is 20kg force with a 12" spanner (effective lever 8"). "Strong arm bar" definitely not required. A 70kg person will push about 20kg with one arm when doing a press-up (offered for calibration purposes).

Well said - I keep overtightening the lockrings on my singlespeed bike and end up breaking the chainwhip trying to get them undone again!

 

[Drago]

If your shifters or mech are Tourney it's likely - but not guaranteed- that your rear end runs a freewheel and not a cassette so won't go to 8 speed. worth checking before spending any lolly.