SRAM PG830 vs PG850 interchange?
 

Hi all,

I'm looking to assemble a custom 8-speed cassette. Do you know if the sprocket and spacer widths are the same for the PG830 and the PG850 cassettes? Has anyone ever mixed cogs from these two cassettes?

If there are differences they are probably minor. I think the difference between the cassettes is in materials but 8 speed cogs are all the same width as are the spacers (within a manufacturing group)

Following up on my old post... Yes, they are the same thickness. The Performance house brand 8-speed cassette also has the same thickness cogs.

I now have a custom frankencog that works great....

I was looking for a new cassette for my old MTB and I thought SRAM PG 850 looks good. Then I noticed there is also PG 830, but I did not find a difference. This caused some confusion.

So, I wanted to know what is the difference if there is any. Then I found an old SRAM document. And the specifications look identical. Except that there is something.

There are three versions of PG 830:

1. MTB 11–32T with sprockets 11-12-14-16-18-21-26-32
2. MTB 11–30T with sprockets 11-13-15-17-20-23-26-30
3. MTB 11–28T with sprockets 11-12-14-16-18-21-24-28

There are five versions of PG 850:

1. MTB 11–32T with sprockets 11-12-14-16-18-21-26-32
2. MTB 11–30T with sprockets 11-13-15-17-20-23-26-30
3. MTB 11–28T with sprockets 11-12-14-16-18-21-24-28
4. Road 12–26T with sprockets 12-13-15-17-19-21-23-26
5. Road 12-23T with sprockets 12-13-14-15-17-19-21-23

So there they are, the only two differences I found. According to 2008 SRAM TECHNICAL MANUAL everything else seems identical. I just did not find any difference between PG 830 11-32T and PG 850 11-32T.

Now I wonder what would be the best option to get a 12-32T version that would have the sprockets 12-13-14-16-18-21-26-32. Because I think I don't really need an 11T sprocket.

Don't be afraid to look at other Shimano compatible brands.

Likely the differences between the 830 & 850 is likely finish and/or weight.

You could -
Use the 6 largest cogs from option 1 of either the 830 or 850.
Add the 2 smallest cogs from option 5, of the 850.


To be honest, you could probably sneak in a Shimano cog or 2 if you really need to.
OR
Just buy this-
https://bikable.com/parts/cassettes/...rew-ring-13-32

Back from the dead after 16 years

There is more to cogs than thickness and spacing. The teeth on neighboring cogs are shaped to work together in upshifts and downshifts. The tips of teeth can be positioned differently within the thickness of a cog. My experience with mixing cogs from different cassettes has been mixed. The shift quality often deteriorated enough to offset the expected gains from more optimal gear ratios.

The Beauty of the Resurrection

The higher numbers denote better materials/heat-treatment/finish; 850 is notionally better than 830, but they're otherwise interchangeable.