Upgrading freewheel

[srnsuki]

Can I upgrade a 6spd 28 to a 7spd 34 like this one?

https://www.alltricks.es/F-11911-ca...bre_de_rosca_shimano_mf_tz31_14_34_dientes_7v

Could it be done if so what would I need if I had to change anything?

https://imgur.com/a/9dLfmem

 

[C R]

Can I upgrade a 6spd 28 to a 7spd 34 like this one?

https://www.alltricks.es/F-11911-ca...bre_de_rosca_shimano_mf_tz31_14_34_dientes_7v

Could it be done if so what would I need if I had to change anything?

https://imgur.com/a/9dLfmem

I think that should be a straight forward replacement, though you may need a bigger spacer, as I think the 7 speed freewheel is wider than the 6 speed. To do the change you will need a freewheel removal tool, and a spanner with a longish handle or a vice, as the freewheel is likely to be rather tight and difficult to remove. Look in youtube for videos on how to remove a freewheel.

Hope this helps.

 

[Ajax Bay]

what would I need if I had to change anything?

Longer chain once you've got a 34t large sprocket.
I shall assume you are content your rear derailleur can cope with both the additional capacity and the 34t 'higher' sprocket. May need to screw in 'B' screw more (if latter dimension (gap between the large sprocket and the guide pulley wheel) is tight.

 

[Tim Hall]

Do you have indexed changers? If so, you'll need ones that can cope with 7 sprockets.

 

[rrarider]

That looks like an enormous size difference between the largest sprocket and the next largest. I think there will be a hell of a clunk when changing to/from that ratio. I think I'd look to read some reviews of its performance before committing myself to purchasing it.

 

[C R]

That looks like an enormous size difference between the largest sprocket and the next largest. I think there will be a hell of a clunk when changing to/from that ratio. I think I'd look to read some reviews of its performance before committing myself to purchasing it.

I have used one, and it is a big clunk going to the 34T, or down from it, but I din't use it very often, so it wasn't a problem, with a long cage derailleur it works fine, just need enough slack in the chain.

 

[rrarider]

I have used one, and it is a big clunk going to the 34T, or down from it, but I din't use it very often, so it wasn't a problem, with a long cage derailleur it works fine, just need enough slack in the chain.

I think @srnsuki will be pleased to read that. You will need to make the change to that large sprocket whilst your legs are still turning the cranks at a reasonable speed, not just before you have completely run out of strength.

 

[gilespargiter]

Their is a very major problem with your proposed change.

You now have a screw on "freewheel" Which you propose to change for a splined "cassette". So you would have to also change the hub to acheive this.

Here is a "freewheel" https://www.ebay.co.uk/itm/Sunrace-...725582?hash=item3d658cb64e:g:udoAAOSwScJa~rJX or here; https://www.ebay.co.uk/itm/7-Speed-...413165&hash=item41b5607ab6:g:FEsAAOSwI~tai3ZA

Can't seem to shorten the links I'am afraid!

You will also need a special tool to unscrew the old one. You will need to check what sort. They are not the same as cassette removers. Here is a link for an example of one - I say again check the sort you need; http://www.wiggle.co.uk/park-tool-freewheel-remover-tool-fr/

I think you will have to look hard to find a "freewheel" with a 32 tooth bottom sprocket, but they can be found.

 

[C R]

Their is a very major problem with your proposed change.

You now have a screw on "freewheel" Which you propose to change for a splined "cassette". So you would have to also change the hub to acheive this.

Here is a "freewheel" https://www.ebay.co.uk/itm/Sunrace-...725582?hash=item3d658cb64e:g:udoAAOSwScJa~rJX or here; https://www.ebay.co.uk/itm/7-Speed-...413165&hash=item41b5607ab6:g:FEsAAOSwI~tai3ZA

Can't seem to shorten the links I'am afraid!

You will also need a special tool to unscrew the old one. You will need to check what sort. They are not the same as cassette removers. Here is a link for an example of one - I say again check the sort you need; http://www.wiggle.co.uk/park-tool-freewheel-remover-tool-fr/

I think you will have to look hard to find a "freewheel" with a 32 tooth bottom sprocket, but they can be found.

The OP is correct, the link is for a screw on freewheel, rosca in Spanish means thread, and if you check Shimano you will see that that model is a freewheel indeed.

 

[gilespargiter]

I might also add the comment that although you have a very reliable and long lasting type of derailleuer - I have a similar one that has lasted over 25years of operating many miles in wet muddy conditions - it will not like jumping the massive gap between bottom gears on the type of "cassette" you show. I don't think it has got the adjustment screw mentioned above.

 

[gilespargiter]

The OP is correct, the link is for a screw on freewheel, rosca in Spanish means thread, and if you check Shimano you will see that that model is a freewheel indeed.

Oops I do beg your pardon - I stand corrected.

 

[rrarider]

Their is a very major problem with your proposed change.

You now have a screw on "freewheel" Which you propose to change for a splined "cassette". So you would have to also change the hub to acheive this.

Here is a "freewheel" https://www.ebay.co.uk/itm/Sunrace-...725582?hash=item3d658cb64e:g:udoAAOSwScJa~rJX or here; https://www.ebay.co.uk/itm/7-Speed-...413165&hash=item41b5607ab6:g:FEsAAOSwI~tai3ZA

Can't seem to shorten the links I'am afraid!

You will also need a special tool to unscrew the old one. You will need to check what sort. They are not the same as cassette removers. Here is a link for an example of one - I say again check the sort you need; http://www.wiggle.co.uk/park-tool-freewheel-remover-tool-fr/

I think you will have to look hard to find a "freewheel" with a 32 tooth bottom sprocket, but they can be found.

No, it is a frewheel. If you search for that Shimano part number, it is described as a freewheel.

 

[gilespargiter]

No, it is a frewheel. If you search for that Shimano part number, it is described as a freewheel.

Sorry as I say made a mistake there. . . .

 

[C R]

Oops I do beg your pardon - I stand corrected.

The website itself is confusing, because it calls it a cassette, but describes it as a freewheel. You are correct about the derailleur, a long cage derailleur with b-screw will be needed to handle that freewheel.

I am thinking that even though it is technically feasible to change, I am not sure it is worth it by the time you add up the cost of all the parts required.

 

[srnsuki]

Oh my god you guys, I forgot about this whole thing. Thank you so much about the comments. This is still very confusing to me!!! I was thinking that maybe I could buy a 6spd. I don't know if I just take it to a bike shop. Do you think it will cost me a lot?? I will probably need a longer chain and new derailleur like you said. I was going to do it myself, but then I read this and it's more complicated than I thought of. Ugh!!