originsoundd
Kona Fan
Ahhh, I see. Thank you! Didn't know that. Is that on the majority of chainrings? I don't recall the previous ones having it.
1996 Kona Hahanna
- Thread starter originsoundd
- Start date
Guinessisgoodforyou
rBotM Winner
Guinessisgoodforyou
rBotM Winner
Fault diagnosis is also easy "Ben what's wrong with this"Shimano middle chainrings got the profiling with M900 XTR. The outers a year or so later with SG-X Dual SIS. The whole range got it in 93. Everyone else had a version soon after as is the way these things go.
bikeworkshop
Old School Grand Master
The rise of front indexing brought us details on the front rings to allow shifting up onto a bigger cog without much overshift, which thumbies were more capable of.
Additionally, the teeth in line with the crank arms are cut down to allow the chain to fall onto a smaller ring.
See how the short teeth are just before the crank alignment pip:
It's a pretty complex design, and if you have the wrong rings or the right ring but with the wrong orientation, the front shifting will be poor.
Cheaper chainrings had less detailing initially, around 1993 it was getting common.
Nowdays if you change one ring size by a tooth or 2, the indexing can become almost unusable, as the chain off the smaller ring might be out of step with the larger ring!
...
Additionally, the teeth in line with the crank arms are cut down to allow the chain to fall onto a smaller ring.
See how the short teeth are just before the crank alignment pip:
It's a pretty complex design, and if you have the wrong rings or the right ring but with the wrong orientation, the front shifting will be poor.
Cheaper chainrings had less detailing initially, around 1993 it was getting common.
Nowdays if you change one ring size by a tooth or 2, the indexing can become almost unusable, as the chain off the smaller ring might be out of step with the larger ring!
...
originsoundd
Kona Fan
Wow, simple and effective. Was wondering why the front mech shifts much better now. Was this ever developed on? By Shimano or anyone else.The rise of front indexing brought us details on the front rings to allow shifting up onto a bigger cog without much overshift, which thumbies were more capable of.
View attachment 943660
Additionally, the teeth in line with the crank arms are cut down to allow the chain to fall onto a smaller ring.
See how the short teeth are just before the crank alignment pip:
View attachment 943664
It's a pretty complex design, and if you have the wrong rings or the right ring but with the wrong orientation, the front shifting will be poor.View attachment 943659
Cheaper chainrings had less detailing initially, around 1993 it was getting common.
Nowdays if you change one ring size by a tooth or 2, the indexing can become almost unusable, as the chain off the smaller ring might be out of step with the larger ring!
...
bikeworkshop
Old School Grand Master
Several companies were working on rear indexing simultaneously, but the introduction of rapidfire plus front indexing necessitated these complex ring shapes to enable the chain to climb up or drop down onto the chosen ring as soon as the derailleur took up that position.
Most other brands stuck with an infinitely adjustable front gear lever, until the point where rf+ dominated the quality mtb scene.
This olders style, particularly the thumbshifter, is still popular with people who like to build their own bikes with a level of mix-and-match, because front indexing needs all components to be compatible.
Most other brands stuck with an infinitely adjustable front gear lever, until the point where rf+ dominated the quality mtb scene.
This olders style, particularly the thumbshifter, is still popular with people who like to build their own bikes with a level of mix-and-match, because front indexing needs all components to be compatible.
