Freewheel Swapping
 

This is probably a stupid question, but if I have a 1985 era wheelset, with shimano 600 hubs, and a six speed hyperglide freewheel, can I just replace it with a 7 speed speed freewheel? I am pretty sure the answer is yes, as long as the threads are the same.

And if so, what brand/type freewheel should I buy if I want compatibility with Shimano index shifting? What are my options? Most freewheels (at least those on ebay) don't really specify the spacing between gears, and it seems like that would be the critical feature.

Shimano

I should have seen that answer coming. And I should have posted this question in the right forum. Can it be moved? Although it doesn't really need to be, since I have my answer.

Jared

do you have 6spd index now? if so you need a 6spd freewheel however I think you can use Shimano Sachs (Aris) and Sunrace
if a 14/28 will work for you, here is one for $21

http://www.loosescrews.com/index.cgi...id=61098162185

How about this one?

http://harriscyclery.net/product/shi...wheel-2694.htm

Seems amazingly cheap. Although technically the ultegra 6503 RD I am using is only rated to 27 tooth. But shimano is conservative, right?

Jared

I don't think one tooth would make a difference.

FYI I moved this to the general C&V forum for you.


OH wait that is a 7spd FW. are your shifters 6 or 7 spd? if they are 6 you need a new shifter. friction nost any FW will work but a hyperglide will shift better

Why? The wheels are currently 6 speed, but they came from another bike. I thought they were interchangeable.

I am switching the entire drive train. The shifters are 8 speed shimano bar ends-- hence the desire to compatible with shimano index shifting.

Jared

OH OK your OP does not only indicates that your wheels are 6spd hence your shifters may or should be 6spd. you did not mention that you were changing the whole drivetrain.

you may need to respace and then redish the wheel slightly.

This I did not know. I was under the impression that since the axle was 126mm for both six and seven speed, that no spacing or re-dishing would be required.

How can I tell if I will need to space or redish the wheel?

Jared

Are 7 and 8 speed cogs spaced the same?
I put a 7 speed IRC Hyperglide freewheel on my previously 6 speed Trek. It's got Suntour friction DRs but man is it smooth. I recommend the IRC if it's compatable.

You do not need to re-dish the rear wheel if you don't make any changes to the hub/axles/spacing. A 6s and 7s freewheel should fit within the 126 spacing you have (mine do but the 7 speed is tight).

However you said you are going to use 8s bar ends for shifters? and a 7s freewheel? Are these friction or index shifting?

Now that you guys mention it, for some reason I thought the 8 speed shifters could index 7 speeds. But I don't remember where I read that. I will have to look into that. . . .

And now I have:

http://www.bikeforums.net/showthread...speed-cassette

http://www.bikeforums.net/showthread...rs-for-7-speed

Doesn't sound ideal, but it sounds like it may work. It makes sense, when they went to 8 speed they also went to 130 spacing, so the difference between cogs did not really have to change much.

Jared

I've done several 6-to-7 upgrades.
Some were just a matter of switching the freewheels.
Some required a couple of spacers.
Some needed re-spacing and re-dishing.
It's going to depend on your hubs and how close the small cog it to the drive side drop-out.
Top

Odds are you'll be OK if you stay with a 7-speed Shimano freewheel.