mtb-timeline

Component	1970s		1980s										1990s
Component	8	9	0	1	2	3	4	5	6	7	8	9	0	1	2	3	4
Rear Derailleur : Suntour	Cyclone GT			Cyclone M2 GT					Cyclone 7000
	36			34					28
	V GT Luxe		aR GT	aRX GT			aR II GT
	36		34	32			34
	AG Tech					AG Tech 5000		AG Tech GTL
	34					34		38
	GT						GT
	36						34
					MounTech 4900				Alpine 5050
					34				38
					MounTech GTL		MounTech II GTL
					38		40
					Superbe Tech L		Superbe Tech GTL			alpha-5000
					34		40
					Le Tech
					40
							XC		XC Sport 6900	XC Sport		XC Pro GX
							38		38	40		40
								XC 3 Pulley¹⁾		XC 9000		XCE
								38		?		?
											XCD6000		XC Comp
											38		39
												XCM		XC Master
												?		?
	8	9	0	1	2	3	4	5	6	7	8	9	0	1	2	3	4
Rear Derailleur : Shimano	600 EX GS						600 EX GS
	34						40
	Skylark			RS12						Tourney TY10				Tourney TY15		Tourney TY20
	34			38						34			34
				Deore	Deore XT			Deore XT (v2)	Deore XT M730			Deore XT M732	XT M735			XT M737
				30		40		40	40			40	40
						Z505		Z503		Z501
						40		40		40
							RD-AL11			Deore RD-MT60		Deore RD-MT62	Deore DX
							40			38		38		38
								Light Action SGS	Light Action SGS	Light Action SGS		Light Action L554
								40	40	40		38
											Exage Mountain		Exage 500 LX			Exage ES
											38		38			38
											Exage Trail		Exage 300 LX			Exage LT
											38		38			38
											Sport LX Long Cage	Mountain LX	Deore LX			LX M560
														XTR M900	XTR M900 SGS		XTR M910 SGS
	8	9	0	1	2	3	4	5	6	7	8	9	0	1	2	3	4
Rear Derailleur: Huret & Sachs-Huret	DuoPar Eco			Duopar Eco
	38			40
				DuoPar Titanium
				36
								New Success			New Success Aris
								42			40
								Rival			Rival Aris		Rival Aris
								40			40		40
Rear Derailleur: Campagnolo	Rally				Rally					Rally
	38				38					34
											Euclid M010-LG
											44
													Centaur
													38
													Themis
													44
	8	9	0	1	2	3	4	5	6	7	8	9	0	1	2	3	4
Component	1970s		1980s										1990s

¹⁾

Disraeligears says this of the XC Triple Pulley: Fantastic - except for the fact that it looked so weird that, as you cycled by, dogs barked, babies cried and your friends laughed. At you, not with you.