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I recently broke my rear Derailleur in my Super Sport 700c SCHWINN S35408M10DSG-LG 7-speed hybrid bike. I tried the Shimano Altus MTB rear Derailleur but I don't like it as much, it feels a bit harder or stiffer to pedal. I appreciate any recommendation or suggestions for a good or great rear Derailleur for a hybrid bike.

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    When shifting requires a lot of force it’s usually more because of friction in the cables than the choice of rear derailleur. Did you install new cables and housing? Did you install it properly? If you are re-using the old cable, maybe it is frayed and leading to increased friction?
    – Michael
    Jun 19, 2022 at 15:21
  • Thanks Michael. I'm re-using the old cable and housing, I only changed the rear deraileur. I didn't think the was cable bad, just noticed the difference btween the old derailleur that came with the bike and the Shimano Altus MTB is replaced it with.
    – jaggsharry
    Jun 19, 2022 at 17:15
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    I think it’s generally better to avoid re-using cables. The ends tend to fray and even if you can get it back in, chances are that it has started to unravel a bit somewhere or has a permanent kink in exactly the wrong spot. For old, dirty cables+housing you can try some thin penetrating oil (like WD40) or silicone spray to improve friction. But generally cables are a wear item and switching to new ones improves shifting more than any other upgrade.
    – Michael
    Jun 19, 2022 at 17:32
  • Thanks, I’ll get new cables with the new derailleur.
    – jaggsharry
    Jun 27, 2022 at 1:33

1 Answer 1

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Based on the information supplied, it appears that your original rear derailleur is a Shimano Tourney RD-TY300. This is a relatively inexpensive rear derailleur, and for your purposes, I would simply replace it, like for like. The Altus RD you tried to use "may" have a different pull ratio or than what your shifters. I did not think that the Shimano pull ratio was different on these up to 9 speed (the Altus appears to be a 9-speed derailleur), but I could be wrong.

To find a direct replacement online, search on "Shimano Tourney RD-TY300"

I found a link to Amazon and a couple other places just with that search.

Searching on your bike revealed the RD is what is shown in this image

Super Sport 700c RD Image

Ensure that the upper mounting point is the same. There are two versions of this RD out there. Make sure it looks like this:

enter image description here

and NOT like this (unless your original one did look this way):

enter image description here

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  • Have you tried looking up the pull ratios?
    – ojs
    Jun 19, 2022 at 22:11
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    All Shimano rear derailleurs marketed at 7, 8, or 9 speed, and whether marketed for road or mountain bikes, all share the same actuation ratio (the lateral movement of these derailleurs is the same per mm of cable pulled by the shifter). Road 10 speed derailleurs (except Tiagra 4700) also have this same actuation ratio. While there are other aspects such as cage length, total capacity and minimum and maximum tooth counts to consider, rear derailleurs from these speed classes are interchangable with each other.
    – Jeff
    Jun 19, 2022 at 23:03
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    It is advisable to replace the internal and external cabling and the installation of a new derailleur is a perfect opportunity to do so. I recommend Shimano branded Stainless steel internal cables with SP41 housing. Complete kits retail for around $20 USD and include inner and outer cables for front & rear derailleurs, all the ferrules you may need and the inner cable end caps. The outer housing is prelubricated but needs to be trimmed to length for the various runs between cable stops on the bike.
    – Jeff
    Jun 19, 2022 at 23:14
  • @Jeff thanks for the confirmation on the common actuation ratio's of the 7-8-9 speed Shimano RDs.
    – Ted Hohl
    Jun 20, 2022 at 15:54
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    Thanks @Ted and Jeff for your input. I’ll get same derailleur with new cabling as suggested.
    – jaggsharry
    Jun 27, 2022 at 1:37

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