Changing from a 7 speed rear wheel to an 8 speed

gt-arrowhead

Hi, I recently nicked the wheels off of my GT to build another bike and i am now left without a pair of wheels for it. I was having a look on eBay and i saw a nice pair on sale locally but they take 8 speed cassettes. The rear wheel that i previously had took a 7 speed cassette. Will the wheel still fit on the frame if it is an 8 speed, or will it be too wide? Logic tells me that an extra gear means that more space is needed, but im not too sure...

My intention is (if i do end up with an 8 speed wheel, and it does fit) is to get a 7 speed cassette on there with a spacer. Reason being is that i only have 7 speed mechs left as spares, so going 8 speed will mean that i will have to buy an 8 speed mech aswell which i dont want.

Thanks

cooldad

7 and 8 speed mechs are the same. The shifters are different.

And it depends if your 7 speed wheel has a freehuib or a freewheel.

If a freehub 7,8 or 9 speed cassettes will fit.

The Rookie

You can fit an 8 speed cassette and index it to use either top or lower 7 then swap the shifter later for an 8 speed, and you then have an 8 speed rear.

gt-arrowhead

cooldad wrote:

7 and 8 speed mechs are the same. The shifters are different.

And it depends if your 7 speed wheel has a freehuib or a freewheel.

If a freehub 7,8 or 9 speed cassettes will fit.

I didnt know they were the same...So my 7 speed Acera will work with my 8 speed Deore LX shifter on an 8 speed cassette?

It will be a freehub, and my previous was also a freehub

So that must mean that 7,8 or 9 will all fit on my frame, since they are all the same length of freehub?

gt-arrowhead

The Rookie wrote:

You can fit an 8 speed cassette and index it to use either top or lower 7 then swap the shifter later for an 8 speed, and you then have an 8 speed rear.

That would be a good idea to fit an 8 speed cassette because i already have an 8 speed shifter, and going by what cooldad says, my 7 speed mech will work on all 8 gears.

Thanks for the help again you two!

The Rookie

Sorted then, all 8 it is!