Road Bike, Cycling Forums banner

1 - 10 of 10 Posts

·
Registered
Joined
·
425 Posts
Discussion Starter · #1 ·
Just got a new SRAM cassette and I see that the spacers between cogs are plastic? I assume you actually install the plastic ones as I can't see how to do it otherwise. Looks like the spacers don't see any real stress or load so I guess it is no big deal but it seems strange to me. Am I missing something?

Mike
 

·
NeoRetroGrouch
Joined
·
6,491 Posts
mprevost said:
Just got a new SRAM cassette and I see that the spacers between cogs are plastic? I assume you actually install the plastic ones as I can't see how to do it otherwise. Looks like the spacers don't see any real stress or load so I guess it is no big deal but it seems strange to me. Am I missing something?

Mike
Would you be happier if the stuck some carbon fibers in the plastic? - TF
 

·
Registered
Joined
·
442 Posts
Nope.

Nope, you are not missing anything. I just got my first 970 and those orange spacers are indeed plastic.
 

·
Registered
Joined
·
100 Posts
mprevost,

What are the weight differences between your old casette and the new one? Sram may be making a smart move on a part that most people wear out & toss into the trash.

When I hear the words plastic I am wont to shudder as I think of shearing forces, but on a free hub perhaps the loads aren't going to be an issue. Now if it were a fixed gear that'd be another issue. Does someone else with an engineering degree wish to elaborate??

Keep in mind that high impact plastic is used for things like SLR camera bodies, laoptop cases, and comsumer electronics. True, they aren't goting to be stressed like a casette, but how much stress does a spacer on a spline go through?

Cheap? Maybe. How much did you pay for it?

You should definately post up in a few months after you've ridden it and let us know how it performs

-Jay
 

·
NeoRetroGrouch
Joined
·
6,491 Posts
giveme2wheels said:
mprevost,

What are the weight differences between your old casette and the new one? Sram may be making a smart move on a part that most people wear out & toss into the trash.

When I hear the words plastic I am wont to shudder as I think of shearing forces, but on a free hub perhaps the loads aren't going to be an issue. Now if it were a fixed gear that'd be another issue. Does someone else with an engineering degree wish to elaborate??

Keep in mind that high impact plastic is used for things like SLR camera bodies, laoptop cases, and comsumer electronics. True, they aren't goting to be stressed like a casette, but how much stress does a spacer on a spline go through?

Cheap? Maybe. How much did you pay for it?

You should definately post up in a few months after you've ridden it and let us know how it performs

-Jay
It's a spacer. The only (small) forces are try to squish it. You could make it out of wood.

TF
 

·
Larry Lackapants
Joined
·
696 Posts
Happened before

I had an old shimano 7 speed cassette 13-21 which also had plastic spacers. It was made/bought a long time ago when 7 speed was not that cheap or outdated, like today it is. I don't think it was high end either (most likely 105 or lower- still it was a cassette and no freewheel). Anyway i've used it for about 15.000km with no issues,the 14 teeth cog was slightly starting to wear out. Then I built up a new bike and sold the old one with this cassette on it.
I don't think you have to worry about the lifespan of those spacers. They can't be destroyed that easily

Cheers
br
 

·
Registered
Joined
·
1,859 Posts
It's common, and not an issue

mprevost said:
Just got a new SRAM cassette and I see that the spacers between cogs are plastic? I assume you actually install the plastic ones as I can't see how to do it otherwise. Looks like the spacers don't see any real stress or load so I guess it is no big deal but it seems strange to me. Am I missing something?
Campagnolo 7spd, 8spd and 9spd cassette spacers have always been plastic. Suntour 7spd and 8spd cassette spacers were plastic. Many Shimano cassette spacers are plastic. I have never heard of an issue with plastic spacers.
 

·
Banned
Joined
·
2,767 Posts
TurboTurtle said:
It's a spacer. The only (small) forces are try to squish it. You could make it out of wood.

TF
Eggzactly! Once the lockring is torqued, those spacers don't really experience anything else. Plastic is perfect for that purpose.
 
1 - 10 of 10 Posts
Top