jdogg111

Hi all, I'm just wondering, since I've heard conflicting stories, about the actual range of the rear derailleur. As a for instance, I currently have a 8 speed cassette on my folder, thinking of going to a 10 since I have one laying around,. I know I have to change the shifter and chain, but won't that same derailleur work, since shifting is indexed? Thanks in advance, I hope it can work, if not with a trigger shifter maybe friction?

Bill Kapaun

What brands, era, road or mountain??

IF you had Shimano compatible components I'd say 8 to 9 speed is no problem. 10 adds a maybe a problem.
There are always exceptions such as some real old Shimao Dura Ace stuff.
Provide more details about what you have re brands & model numbers and one can give much better answers.

SpedFast

Disregard, sorry

SoSmellyAir

Assuming (based on market share) that all components you have mentioned are made by Shimano, theoretically, yes, even with an indexed shifter.

What are the standard speeds? - Bike Forums

Lombard

Need more info. Shimano, SRAM or Campy? Road or mountain group set?

If Shimano road, 8, 9 and 10 speed are interchangeable since the shift ratios are the same, so the 10-speed shifter will work fine with the 8-speed derailleur. If Shimano mountain, 10-speed is a different shift ratio and an 8-speed derailleur won't work with a 10-speed shifter.

kommisar

I find this crib sheet to be particularly useful when dealing with drive trains:


https://sheldonbrown.com/cribsheet-spacing.html

SJX426 

@jdogg111 - You said you have a folder. What size wheels? Shimano made a rear cassette with a 9 tooth sprocket. It is only compatible with itself. check it.
What size wheels do you have or what brand folder is it? Some have really unique components.

momoman

jdog111, I had the same question in mind! Like you, I was also thinking of upgrading the Zizzo Liberte’s stock drive chain from an 8-sp to either a 9 or 10-sp.

The stock components are:

Shimano Revo 8-Speed Grip Style Shifter with Gear Viewing Window
Shimano Altus 8 speed direct mount RD
Suntek Nickel Plated 11-32T 8-Speed cassette
20” 406 130mm OLD rear wheel.

jdogg111

yea. sorry for not mentioning the name of the bike. zizzo liberte, i'm thinking its sora on the rear.

Lombard

8-speed derailleur will work fine with 10-speed Shimano road shifter and cassette. Keep in mind that 8, 9 and 10 speed cassettes are all the same total width, but the spacing between cogs became less as number of cogs increased. The range of the rear derailleur is the same.

Camilo

There's a delete function.

Bill Kapaun

Actually, this poster shouldn't have deleted their post-
I beat them by a few seconds and we were pretty much saying the same thing.
However, this poster also mentioned a maximum cog size being a possible factor. I failed to do so.
2 people answering the same way within minutes of the OP simply reinforce each other.

Camilo

I only mentioned it, not to scold (hope it didn't come off that way), but in case the poster didn't know there's a delete function. Machts nichts either way.

HTupolev

It'll only work with the shifter if it's pre-2015. Starting with Tiagra 4700, Shimano's road 10-speed groupsets have shared rear derailleur actuation with the 11-speed road stuff.

Lombard

True. I stand corrected. But so far, the newer Tiagra is the only 10-speed group with the 11-speed shift ratio.

The OP needs to look for a shifter that is 5600/6600/7800 or earlier generation.

Iride01 

If you already have the stuff, then why not try it and see? However if you have indexed shifters, then you need to get 10 speed indexed shifters. Of course friction shifters might work. But I'll think that finding the right place to catch a particular gear will be a little more fiddly for you. But I don't know I went to indexed after leaving 6 and 7 speed freewheels.

Width difference of a 8 speed cassette and 10 speed cassette might be the same to a couple mm depending on what exactly you have. A bigger concern for the cassettes might be if the large cog on the 10 speed is larger than the large cog of the 8 speed. Some DR's might not clear that gear as they travel to the low gear side.

If you adjust your limit screws out all the way then you can see what the full swing is on your DR by disconnecting the cable and simply pushing on it and measuring.

SpedFast

Thanks Bill,

SpedFast

Yeah, but I still wanted to follow the thread and the edit was quick and easy.

Lombard

The other possible issue here is total chain capacity of the RD cage.

HTupolev

GRX400 also fits the bill.

Lombard

I didn't know GRX400 was only 10-speed. Noted.