Rear derailleur compatibility quesion

sonofsouth
sonofsouth Posts: 7
edited January 2018 in The workshop
Hi guys.

My lad broke his 8 speed rear derailleur.

Shimano Tourney TX35 on ebay is being advertised as both 6,7 speed and 6,7,8 speed with some sellers.
All major retailers are describing it as 6,7 speed only.
I ask because 8 speed derailleurs are double the price of 6,7 speed ones and if i can get away with using it, why not?

Will TX35 work as 8 speed derailleur?

Thanks.

Comments

  • The Rookie
    The Rookie Posts: 27,812
    Probably......
    It will shift just fine but there is a small chance (though very very unlikely now) that the 6,7 are old stock and don't have enough movement for the extra gear, but to be honest, by now, its vanishingly unlikely.
    Currently riding a Whyte T130C, X0 drivetrain, Magura Trail brakes converted to mixed wheel size (homebuilt wheels) with 140mm Fox 34 Rhythm and RP23 suspension. 12.2Kg.
  • This is the Shimano drivetrain hierarchy;

    http://productinfo.shimano.com/#/lc/2.4

    Ideally you should buy a TX-800 its a pretty decent derailleur or try to find a Altus or Acera cheap most can be got sub £15 on occasion. It should work though but might need more maintenance. If he broke the last derailleur somehow maybe something stronger is needed. A derailleur guard/protector too?
  • 9-speed rear derailleurs will work with 8-speed too and can often by found under £30.

    What I cannot remember in my sorry state today is whether road and mtb drivetrains are inter-changeable up to and including 9-speed, I think they are.

    I've been thinking about replacing/upgrading the RD-M310 on my Wazoo with either RD-M591 eg. http://www.wiggle.co.uk/shimano-deore-m ... -rear-mech or RD-M592 http://www.halfords.com/cycling/bike-pa ... leur-black (but being a rookie in replacing default rear mechs, I've no idea whether both are even an option for me).
    ================
    2020 Voodoo Marasa
    2017 Cube Attain GTC Pro Disc 2016
    2016 Voodoo Wazoo
  • The Rookie
    The Rookie Posts: 27,812
    Road and MTB are compatible up to 9 speed MTB and original 10 speed Road, after that it all goes a bit bananas with dynasis and then some road stuff changing as well.
    Currently riding a Whyte T130C, X0 drivetrain, Magura Trail brakes converted to mixed wheel size (homebuilt wheels) with 140mm Fox 34 Rhythm and RP23 suspension. 12.2Kg.
  • cycleclinic
    cycleclinic Posts: 6,865
    O wrote a reply about shifters! Doh
    http://www.thecycleclinic.co.uk -wheel building and other stuff.