Need a New Hyperglide Cassette.....

StuInTokyo

Maximum Pace
Dec 3, 2010
1,662
62
78
#1
OK, my old 7s hyperglide cassette is giving up the ghost, I have several "Crunching" moments on almost every ride.

I recently bought new wheels, Shimano WH-M505, yeah I know heavy, but so am I and they are supposed to put up with daily abuse, so that is what I got.

My bike is a 1988 Cannondale SM500 MTB, that I only ride on the road now, I use it to haul my trailer around doing deliveries for our liquor shop.

View attachment 656
Before the fenders, rack trailer hitch etc.

The new wheelset will let me put an 8 speed cassette on the bike, and I have a nice NOS set of Shimano Deore thumb shifters that have the 8th ghost click, so I'm going with the 8 speed cassette.

Now I have this for gearing...

Front:
28T
36T
48T

Rear:
(7 speed)
13-23T (12,13,14,15,17,19,21,23)

I'm looking at this cassette...
View attachment 657 View attachment 658
8-speed
12-25T (12,13,15,17,19,21,23,25)
This is the "W" group cassette.

Not a huge change, but a change.

I understand that the 11T cog cassettes will only work with the Hyperglide Compact
I would not mind having the lower gears for climbing with a full trailer, so the 12-25T looks good

I also see a "V" group cassette
13-26T (13,14,15,17,19,21,23,26)

I know it comes down to a personal preference, so what I'm asking is if this is "Correct" as in do these parts play well together.

Cheers!
 

AlanW

Maximum Pace
Jan 30, 2007
1,214
435
103
Tokyo
#2
Should work fine.
8 speed with the Deore shifters is a little bit fussy to set up as the inter-cog spacing is very slightly different but it will work. 7 speed rear mech will be OK.

If your wheels are modern MTB wheels they will most likely take an 11 tooth top cog cassette but you probably won't get much use from a 48/11 gear on a mountainbike - best to stick with the 12 or 13.

Don't forget to change your chain as well when you change cassette. The 7-speed chain a) will not work very well and b) as it's old, will eat your new cassette. And you will need to add extra links to allow for the larger bottom cog (25/26 vs old 23).
 

StuInTokyo

Maximum Pace
Dec 3, 2010
1,662
62
78
#3
Should work fine.
8 speed with the Deore shifters is a little bit fussy to set up as the inter-cog spacing is very slightly different but it will work. 7 speed rear mech will be OK.

If your wheels are modern MTB wheels they will most likely take an 11 tooth top cog cassette but you probably won't get much use from a 48/11 gear on a mountainbike - best to stick with the 12 or 13.

Don't forget to change your chain as well when you change cassette. The 7-speed chain a) will not work very well and b) as it's old, will eat your new cassette. And you will need to add extra links to allow for the larger bottom cog (25/26 vs old 23).
Great, thanks Alan, and I always change my chain when I get a new cassette.

I thought that the 7 and the 8 speed cassettes had the same, or very similar spacing, so I figured the 8 speed shifter that works great on the 7s cassette, adding one more cog to make it 8, it would work fine...?

The front chain rings should be OK, I guess, the middle one, which gets the most use, is only about a month old.

Cheers!
 

StuInTokyo

Maximum Pace
Dec 3, 2010
1,662
62
78
#5
7 speed spacing is 5mm between cogs; 8 speed is 4.8mm.
There's enough tolerance in the system to deal with this small difference.

The late Sheldon Brown, as ever, has all the answers.

http://sheldonbrown.com/cribsheet-spacing.shtml
Thanks Alan, I had looked at that site, but I did not see that page.

I shall find out, on they way home from the hospital I went to Y's Road Shinjuku and got a new cassette and chain, now I'm off to my workshop to do the swap.

Cheers!
 

StuInTokyo

Maximum Pace
Dec 3, 2010
1,662
62
78
#7
I futzed with it last night and on my daily ride to the hospital to get my interferon shot (OUCH) I tried it out..... :thumb: shifts are now super smooth and no crunching or skipping of gears. I got to pushing the big gear more on the flats, and my average speed certainly improved, but boy does it knock me on my arse, still looking for that fitness I lost before I got sick, anyone find it? :D

Thanks again Alan for confirming my selection of parts, it was dead easy to go down to the Shinjuku Y's Road and pluck the bits from the shelves, and as a bonus, they were cheaper there than where I was looking online! Only 2,411 yen for the cassette, online it was 2,500 yen plus 550 yen shipping.