Bicycle Mechanics - Shimano Cassettes inquiry

I am trying to buy a Shimano cassette but am confused that they have a Dura-Ace, Ultegra, 105 line and at same time they have the HG-50, HG-80, etc line. Sometimes the gearing spread of an Ultegra can be the same as one in the HG-50 line.

I can understand the DuraAce, Ultegra, 105 heirarchy but how do they relate or differ from the HG line?

HG stands for hyperglide, which all modern shimano cassettes use. The numerical part of the HG-labeled cassettes will tell you roughly where they stand; for road groups, sora is 3xxx series, tiagra 4xxx, 105 is 5xxx, etc. In the mountain world, they have it a bit different, with plain deore at 5xxx, slx at 6xxx, xt at 7xxx, saint at 8xxx, and xtr at 9xxx. Things don't run congruently on the road and mountain lines; the saint and xtr are no "better" than the dura-zce stuff. They just used to have, like, a million different mtb groups. The second number is typically indicative of a generation; 6600 is the last gen ultegra. The current generation is 6700,When they redesign it from the ground up again, it'll most likely be 6800. Numbers after the second will typically indicate options; ultegra cranks came in fc-6600 (double), fc-6650 (compact double), and 6603 (triple) flavors, for instance. Sometimes, the "50" can be a mid-generation tweak, when they fixed the goofy cassettes and freehub bodies in the dura-ace.

Cassettes marketed as HG-50 are likely to be non-series stuff, oem pull-offs or overstocks, or non-current new stock. These days, the alphanumerics for cassettes tends to be stuff like cs-6700. You can figure that a road hg-50 will be roughly equivalent to 105, but that's sort of arguable. In the end, most of the shimano stuff is compat, assuming the number of speeds match between cassette, shifters, and r.derailer, and that your r.derailer is equipped to tackle the largest cassette cog and the total chainwrap. So, if you're grabbing a cassette for your roadbike, make sure you're getting a 9speed cassette, with no larger than a 28t rear cog. Don't sweaT the label too much; no one will care if you don't.

-rob

Cassettes marketed as HG-50 are likely to be non-series stuff, oem pull-offs or overstocks, or non-current new stock. These days, the alphanumerics for cassettes tends to be stuff like cs-6700. You can figure that a road hg-50 will be roughly equivalent to 105, but that's sort of arguable. In the end, most of the shimano stuff is compat, assuming the number of speeds match between cassette, shifters, and r.derailer, and that your r.derailer is equipped to tackle the largest cassette cog and the total chainwrap. So, if you're grabbing a cassette for your roadbike, make sure you're getting a 9speed cassette, with no larger than a 28t rear cog. Don't sweaT the label too much; no one will care if you don't.

-rob

Current Deore and SLX still use the HG numbers (HG61, HG80, HG81)

HG stands for hyperglide, which all modern shimano cassettes use. The numerical part of the HG-labeled cassettes will tell you roughly where they stand; for road groups, sora is 3xxx series, tiagra 4xxx, 105 is 5xxx, etc. In the mountain world, they have it a bit different, with plain deore at 5xxx, slx at 6xxx, xt at 7xxx, saint at 8xxx, and xtr at 9xxx. Things don't run congruently on the road and mountain lines; the saint and xtr are no "better" than the dura-zce stuff. They just used to have, like, a million different mtb groups. The second number is typically indicative of a generation; 6600 is the last gen ultegra. The current generation is 6700,When they redesign it from the ground up again, it'll most likely be 6800. Numbers after the second will typically indicate options; ultegra cranks came in fc-6600 (double), fc-6650 (compact double), and 6603 (triple) flavors, for instance. Sometimes, the "50" can be a mid-generation tweak, when they fixed the goofy cassettes and freehub bodies in the dura-ace.

Cassettes marketed as HG-50 are likely to be non-series stuff, oem pull-offs or overstocks, or non-current new stock. These days, the alphanumerics for cassettes tends to be stuff like cs-6700. You can figure that a road hg-50 will be roughly equivalent to 105, but that's sort of arguable. In the end, most of the shimano stuff is compat, assuming the number of speeds match between cassette, shifters, and r.derailer, and that your r.derailer is equipped to tackle the largest cassette cog and the total chainwrap. So, if you're grabbing a cassette for your roadbike, make sure you're getting a 9speed cassette, with no larger than a 28t rear cog. Don't sweaT the label too much; no one will care if you don't.

-rob

okay, that's clear. thank you for the help.

Current Deore and SLX still use the HG numbers (HG61, HG80, HG81)

nice to know. =)

-rob

okay, that's clear. thank you for the help.

anytime, bro

-rob

Cassettes marketed as HG-50 are likely to be non-series stuff, oem pull-offs or overstocks, or non-current new stock. These days, the alphanumerics for cassettes tends to be stuff like cs-6700. You can figure that a road hg-50 will be roughly equivalent to 105, but that's sort of arguable. In the end, most of the shimano stuff is compat, assuming the number of speeds match between cassette, shifters, and r.derailer, and that your r.derailer is equipped to tackle the largest cassette cog and the total chainwrap. So, if you're grabbing a cassette for your roadbike, make sure you're getting a 9speed cassette, with no larger than a 28t rear cog. Don't sweaT the label too much; no one will care if you don't.

-rob

Not exactly accurate. HG50 <> 105 level cassette. HG50 is just plain HyperGlide 50. It is below that of 105 which is cs-5xxxx. Current 105 cassettes are 10spd. HG50 or HG70 can be found from mtb to road application. If it is 8-speed road, it is often matched with Sora/2200 groups. If it is 9-speed it is Tiagra/Sora. HG50 can also be found in MTB normally with 32t or 34t as their largest cogs and are often called Deore by some resellers.

See Shimano Compatibility Chart for ref: http://bike.shimano.com/publish/content/global_cycle/en/us/index/tech_support/tech_tips.download.-Par50lparsys-0025-downloadFile.html/01%29%20Drivetrain%20Compatability%20Chart.pdf

Current Shimano mountain cassettes (in ascending order):
CS-HG40-8 - Altus, Acera (8-speed)
CS-HG50-8 - Alivio (8-speed)
CS-HG50-9 - new 9-speed Alivio, Deore
CD-HG61-9 - Deore (9-speed)
CS-M580 - Deore LX (Deore LX is now a trekking group) (9-speed)
CS-HG80 - SLX (9-speed)
CS-HG-81-10 - new 10-speed SLX
CS-M770 - Deore XT (9-speed)
CS-M771-10 - new 10-speed Deore XT
CS-M970 - XTR (9-speed)
CS-M980 - new 10-speed XTR

From SLX level (CS-HG80) and up, the cassettes have spiders/carriers.