tpadul 

I知 still very much a newbie when it comes to bicycle mechanics so be gentle in your responses . I just purchased this old Fuji all terrain bike that is set up to utilize a 6 speed freewheel/cassette and it has a triple chainring. I know the rear derailleur and the shifters will not accommodate a 9 speed cassette but I知 ok with the cassette only being able to utilize 6 speeds.

The 9 speed cassette came with a 26 inch wheel set I just bought the other day. The frame does not come with the original wheel set so I wanted to use the wheel set I just bought but I知 not sure if it will work or not?

I would rather not put a lot more money into the bike so changing the rear derailleur and shifter would probably not be as cost effective as just removing the cassette and getting a 6 speed cassette. I know a 6 speed cassette is $35 at my LBS. Figured I could sell the 9 speed cassette for a couple dollars.

I知 not planning on flipping the bike at all so if I can somehow still use the 9 speed cassette with the knowledge that it will not be able to use all 9 speeds I知 ok with that.

Thanks so much for your advice.

alcjphil

Nobody makes 6 speed cassettes any more. If your wheel has a 9 speed cassette, what you are thinking of buying is a 6 speed freewheel, not a cassette. They are not interchangeable. If you want to use your current shifters you will need a different rear wheel

icemilkcoffee 

1. The shifters are indexed to 6 speed. So it will not work with that 9 speed cassette. Nor will it shift (well) through 6 of the 9 speed, bbecause the cog spacing is different.
2. You pretty much will not be able to find a 6 speed cassette (as opposed to a 6 speed freewheel). Even if you do, the 6 sp cassette is UG, and might not fit onto a newer HG hub.
3. The rear wheel you bought has 135mm spacing. Your frame probably has 130mm spacing. Or maybe even 126mm for a few odd ducks.
If I were you I would hold out for rear wheel with the right 6 speed and the right spacing.

Bill Kapaun

Measure your spacing first. It's conceivable it might be as narrow as 120mm, but likely 126mm.
Spreading the frame to 135mm without aligning the DO's will cause short bearing life. You can typically spread about 4mm and not be too bad.

tpadul 

Yes, I meant swapping out a the 9 speed cassette with a 6 speed freewheel, and this is the info I was looking for, I wasn't sure about the 9 speed cassette working because I remember someone else talking about the spacing between the cogs being different in another post. Thank you so much for your replies, I will keep my eyes open for another wheel set that will fit this Fuji bike.

Iride01 

If that is really the goal, then just get everything running as it is. If that is your goal in a future purchase, make certain everything works.

Cheap components work for some upgrading their bikes, but they don't for me. I'd stick to Shimano, SRAM and Campagnolo. Out of those three Shimano usually has lower tier inexpensive groups.

Eric F 

You have opened a much bigger can of worms than you know.

The spacing between cogs on 6-speed is different than 9-speed. This means that your 6-speed shifters will never properly index with a 9-speed cassette, and things will be messy. There are 6-speed cassettes available on eBay (make sure it's a cassette, not a freewheel - search for "Shimano 6 speed uniglide cassette") that will probably give you the result you want. If your LBS has one, that's a good option, too. All that said, I'm not 100% sure if the freehub body on the 9-speed wheel is the same size needed for a 6-speed cassette. Spacers may be required, or it might not work at all. Your LBS might be able to help you with this issue, too.

To use the 9-speed cassette, you would need (at a minimum) a new rear derailleur, rear shifter, and chain...and probably derailleur cable and housing.