first trip

can i fit any rear derailleur on a 6 speed freewheel or does the rear derailleur has to be labeled 6.

what about the shifting manettes?
tx

dabac

I believe any Shimano MTB derailer up to 9-speed should work. Pick a Tourney and be Done with it.

Don’t know what a ”manette” is.

dedhed

French for "controller" or lever

_ForceD_

You didn’t mention in the OP...is this an indexed or friction shifting system? If it’s friction...you should probably be able to use just about any derailleur.

Dan

Bill Kapaun

6/7 speed has wider cogs, spacing & chain than 8 & above.
Just get a Shimano Tourney.
DER's for 8 & above start to get narrower and are more prone to chain rub.

cyccommute 

Yes. But I wouldn’t go that far down the Shimano line. Altus is low enough without going into the sewer.

first trip

hi are you saying that investing a bit more money is not worth the quality of alivio or other higher that tourney. Im curious if you could share us what you base your legitimate opinion, it would bring clarity to me tx

first trip

i prefer indexed

first trip

is a 6 speed narrower in its global width than a 7 speed?

about tourney are you saying additional investment is not worth it?

cyccommute 

I would say that spending money on the Tourney is just wasted money. The secondary market Tourney is slightly better then what you’ll find on HelMart bikes but only slightly. I’ve worked on a lot of Tourneys and they are all rather flexible. Flexible and precise index shifting don’t go to together all that well. Alivio and higher derailers are stiffer and work better. Tuning them to shift well is just easier.

70sSanO

I agree that an Alivio or Acera mtb rear derailleur would be a good choice. If you have access to a good mtb rear derailleur from the 90’s that will also work.

Basically any 6-9 speed SIS mtb rear derailleur will work. There is no concern about cage width. KMC sells their X8/X8.93 chain for 6/7/8 speed cassettes. I run this chain through 9 speed rear derailleurs for 7/8 speed setups without any issues.

John

first trip

my bike is not a mountain bike it is a stepthrough norco york ville

im not clear if aliexpress is second market or if shimano is ?
do you mean whatever comes stock with a new bike is lesser quality than a piece of the same name an companie bought separately?


Are you guys saying that whether i choose a claimed 7 rear derailleur or a 9 or 10 or 12 it does not change anything? they will all work well with a 6 speed?
wouldn't that be safer to choose a claimed 7/6-speed

like this one does not say 6 speed it says SHIMANO Alivio M3100 RD-M4000 27 Speed RD M4000 Mountain Bike Shadow 9-speed Rear Derailleur m3100 new model of m4000

would it work well for 6speed??

https://www.aliexpress.com/item/33054482054.html?spm=a2g0o.cart.0.0.11d43c00psAykd&mp=1

Bill Kapaun

You need to read and THINK before you keep tossing questions back.
This isn't Siri!

cyccommute 

The equipment that comes on a bike is called OEM which stands for “original equipment manufacturer”. Ignoring the tortured grammar (would a comma kill ya), OEM just means what comes on the bike. A “secondary market” would be if you bought a replacement part and put it on in the place of the OEM equipment. It’s also called “aftermarket”. Again ignoring the tortured grammar (would a space or hyphen kill ya!), it just means that you buy it and have it put on or put it on yourself. Where you buy it from doesn’t matter. Shimano makes the part but they don’t sell it direct to the consumer. Any item you buy from a shop is “after market”.

HelMart bikes (aka Big Box Store) bikes have even lower quality Tourney rear derailers than what you can buy in the after market. After market Tourney is almost okay but it is still a rather flexible derailer. A stiffer derailer (Alivio and above) is more precise and easier to tune.

Yes...kinda...that is what we are saying (in a less shouty manner). But here’s the kinda bit. As long as the derailer is for a 9 speed (or less), it will work. 10 speed and higher use a different pull ratio and won’t work with your shifters. It doesn’t matter that the derailer is a “mountain bike” derailer, it will work. The derailer is basically a robot and does what the shifter tells it to do. As long as the pull ratio is right, the derailer doesn’t care how many speeds the bike has.

alcjphil

In order for a derailleur to work on a 6 speed freewheel you will of course have to use a 6 speed shifter. If you don't currently have a 6 speed shifter you will have to buy one

70sSanO

I would add this is important, since I don’t think Norco ever made a Yorkville step-Thru with a 6 speed freewheel.

And you should probably talk to the mechanic who is going to install the components for you.

John

shelbyfv

Or just let the mechanic source the proper parts.

first trip

Hi
seems like part of you is insatisfied . sorry for that . since there are many questions, a consider your comment only as semi pertinent. Also asking for a confirmation is an act of gentlement utilizing his pesos wisely if it can reassure you.

first trip

hi,
first sorry for missed grammar, it is not my native language and to be honnest i feel anxiety when i ask for help in a field i dont know so it is possible i m so anxious my typing is less than perfect. that is the way i am today trying to better ...
i never heard avout he pull ratio but i trust you. then how to select the manettes lever control ?

and i dont want to anoy you but would a 6-7 derailleur be better than a 9 speed for example?
tx for teaching me the basics

first trip

you are right originally it is a 21 but since i put a hubmotor electric in back wheel, it need space and 7 speed is too tight so i ll try with a 6 speed hoping it will give me more space... maybe 1 cm? could you say?
tx
since i want to learn and i m broke ill go in a do it yourself shop and order by myself.

first trip

hi
english is my second language . is a shifter the thing you move with your finger to change difficulté speed? or other part?

shelbyfv

Here is good info you can absorb at your leisure. Best to have a basic understanding of these things before you start your project. https://www.sheldonbrown.com/bicycleGears.html

cyccommute 

You don’t really need to worry too much about pull ratio unless you are trying to use a 10 speed and above shifters. The 10 speed shifter has a different pull ratio and won’t work with 9 speed and less shifters. I’m assuming that you are just replacing the derailer on an existing system so shifter selection has already been done for you. That dictates the type of rear derailer you get. If you want to change the number of gears you have, that would mean new shifters as well as other parts. I’d suggest just staying with what you have now.

It doesn’t matter. 6 and 7 speed systems are somewhat obsolete but since they used the same pull ratio as 9 speed, a 9 speed derailer will work. Since those are still available, just use the 9 speed. It won’t make any difference nor will it shift any better or worse.

Iride01 

Until you get some experience, you'll be much better off if you just match all the components of your drive train. Use the same model and series front and back DR and shifters. Pick cassettes and chain wheels that Shimano shows as compatible with that specific model line..

Don't mix up even the same model with a much earlier series of that same model, because many times it will have some incompatibilities. DuraAce today won't work with DuraAce of 10 years ago.

Shimano has compatibility charts and other tables to help you figure this out. https://si.shimano.com/#/

70sSanO

Now I understand. To be honest, the first step would have been to “first” research hub motor over locknut width required and the rear dropout spacing on your bike.

I only spent a few minutes Googling it, but if your hub motor requires 135mm or more and your aluminum frame spacing is 130mm, or worse at 126mm, it will not fit.

I would ask in the Electric Bikes subforum if it will work. And you need details as to the bike you have and the hub motor you want to use.

You will not save 1cm between a 6 and 7 speed freewheel. You “might” be able to use a 5 speed freewheel with friction shifters and re-space the hub motor to fit narrower dropouts. I just don’t know. But it is way beyond just buying a few parts and hoping for the best.

Good luck.

John