Question: Would FH-RM30 7-Speed Freehub Body work on 8/9-speed FH-M570 hub?
#26
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I tried that, wrote it on Word and then copy/pasted it. Seems to be the website with excessive roadblocks and repeated needs to log in, probably for security reasons.
I appreciate detailed thoughts, which can require equally detailed responses, which can take time to write, which brought me to Word and copy/paste.
I appreciate detailed thoughts, which can require equally detailed responses, which can take time to write, which brought me to Word and copy/paste.
#27
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7 speed freewheels became so prevalent in the 80’s because the upgrade was so easy back then. With friction shifting, just thread on the freewheel, adjust the limit screws and you were set. 6 speed virtually disappeared since the upgrade required no modification of frame or hubs.
When 8 speed came along, (especially HG only “C” freehubs that ushered 11t cogs), that was the base for 9 and 10. Why run 8 speed when you can run 9. We only have one 9 speed bike, but I think 9 might represent some of the best that Shimano produced.
9 speed is backward compatible and across road and mtb, with the FD being the only hiccup. Increased capacities and max cogs with a spacing makes it pretty trouble free regardless of the abuse.
I am fine with 8 speeds because I’m old and don’t mind giving up some top end. Going to 9 or 10 speed just adds 11t and 12t cogs. Now if I were 40 years younger, I’d probably toss all this garbage out and run 11speed.
John
When 8 speed came along, (especially HG only “C” freehubs that ushered 11t cogs), that was the base for 9 and 10. Why run 8 speed when you can run 9. We only have one 9 speed bike, but I think 9 might represent some of the best that Shimano produced.
9 speed is backward compatible and across road and mtb, with the FD being the only hiccup. Increased capacities and max cogs with a spacing makes it pretty trouble free regardless of the abuse.
I am fine with 8 speeds because I’m old and don’t mind giving up some top end. Going to 9 or 10 speed just adds 11t and 12t cogs. Now if I were 40 years younger, I’d probably toss all this garbage out and run 11speed.
John
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And such questions really belong in the Forum Suggestions & User Assistance . That way they won't de-rail a thread further than the stuff that has already derailed this thread.
#29
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#30
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But over the years I have acquired a stash of enough various cassettes, individual cogs, and spacers that I can build just about anything I want by mixing and matching cogs and brands. My franken-cassettes include 8 speed 13-40 and 14-36.
If I were starting from scratch today, I’d just go to 9 speed.
John
If I were starting from scratch today, I’d just go to 9 speed.
John
I think the 36T freehub cog was the main attraction of 9-speed, but 9-speed was the beginning of gear train strength and durability compromises, although not by much, and then 10-speed went off the edge of a cliff.
Last edited by reroll; 07-21-22 at 01:43 PM.
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I am a member of the Frankenbike gear train club and have my own collection of various components, too.
I think the 36T freehub cog was the main attraction of 9-speed, but 9-speed was the beginning of gear train strength and durability compromises, although not by much, and then 10-speed went off the edge of a cliff.
I think the 36T freehub cog was the main attraction of 9-speed, but 9-speed was the beginning of gear train strength and durability compromises, although not by much, and then 10-speed went off the edge of a cliff.
My 14-36 consists of a Shimano 14t 11 speed first position cog (ebay), 16t-18t-20t-23t-26t-30t Shimano HG 50 9 speed, I added a Sunrace 36t (9). The theoretical 8 speed cog thickness is 1.80mm and 9 speed cogs are 1.78mm. I imagine the same sheet stock is used for both since .02mm = .0008" and probably within the stock material thickness tolerance. 7 speed cogs are 1.85mm so the max cog difference to 9 speed is .07mm or .003". Even that is within the plastic spacer tolerances I have seen.
John
#32
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You could easily be right as I am not using a Microsoft or an Apple browser, what I am using is set for high security, I did mention this could be a security matter and here on Bike Forums I continue to encounter what appear to be security-oriented roadblocks, including getting timed out. But OK, this is a long established forum and website having many years of online experience, where security and website success and longevity would be of high priority and methods would have been devised to provide such security. I just need to figure out how to negotiate this format which would take some experimental time for me to do, no problem.
#33
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Funny, I always think of 7-speed cassette as that forgotten middle child. Bikes were largely 6-speed up to the late 80s, then Shimano would upgrade a group to 7-speed, only to bump it up again to 8-speed within a couple years. And frames and freehubs intended for 7-speed didn't provide as easy a path for upgrades as 8-speed... so 7-speed became a mid-to-lower tier thing pretty rapidly.
Once upon a time there were 5-speed hubs which fit into 120mm dropouts and then efforts were made to fit 6 speeds into 120mm, the narrow Ultra freewheels, for instance. But they met with only limited success and so dropouts were commonly changed to 126mm to fit 6 cogs with "regular" cog spacing. Then it was discovered that freewheels could work successfully with narrower cog spacing, that a 7-speed freewheel could be only slightly wider than the earlier 6-speed freewheel, and because bicycle rear dropout spacing had never been entirely standardized it turned out that 7-speed freewheels could often fit into dropouts designed for 6-speed freewheels although it also often happened that maybe a few millimeters of spacers would be needed to spread the dropouts outward slightly to get the 7-speed freewheels into place. Yet despite such occasional needs to use thin spacers and although 120mm rear dropout spacing became obsolete near the end of the 1970s or so, 126mm dropouts and 7-speed freewheels were in use until the later 1980s along with reported axle troubles with 8-speed freewheels using 130mm dropout spacing, when Shimano introduced its SIS shifting system in 1986 which Shimano made available only on its newer freehub hubs with 6-speed cassettes, followed by 7-speed cassettes in 1987, followed by 8-speed cassettes in 1988 and which soon caused freewheels to become obsolete in the Western bicycle market although even now, in 2022, the massive Eastern bicycle market still includes the widespread use of freewheels.
Last edited by reroll; 07-22-22 at 06:16 AM.
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