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-   -   Chainrings With or Without Pins? (http://www.bikeforums.net/bicycle-mechanics/351563-chainrings-without-pins.html)

Motorad 10-08-07 06:00 PM

Chainrings With or Without Pins?
 
When using bar end shifters for a 10-speed cassette, does it matter (and why) if the chainrings are pinned to ease shifting for a double crankset?

When using bar end shifters for a 10-speed cassette, does it matter (and why) if the chainrings are pinned to ease shifting for a triple crankset?

sch 10-08-07 06:27 PM

Yes it makes a difference, though only going from smaller to larger chain wheels.
So in a double the largest CW and in a triple the mid and large CW should be pinned
and relieved for best shifting. You don't realize what the pins do til you go back to
your old '70s era bike and discover what you have gained.
A study of the cassette will show all the cogs are pinned as well.
It works.

Al1943 10-08-07 07:51 PM

I think ramps and pins are more important for indexed shifting. Friction shifting works fine without.
The ramps and pins help the chain climb from a smaller chainring to a larger chainring. With friction shifting you can over shift and then trim back but with index shifting there needs to be greater accuracy because the derailleur cannot move the chain as far laterally or back up.

Al

HillRider 10-08-07 08:01 PM

Quote:

Originally Posted by Al1943 (Post 5417450)
I think ramps and pins are more important for indexed shifting. Friction shifting works fine without.l

Almost. Ramps and pins are essential for good index shifting. Ramps and pins noticeably improve friction shifting.

I have an old Trek road bike I use as a beater. It originally had an SR triple crank with plain flat chainrings and barcon shifters (friction in front of course). Shifting even from large to the middle ring was not very precise and was very sluggish under load. I replaced the SR with a Shimano 105 triple and, using the same barcons, front shifting is worlds better.

erader 10-08-07 10:21 PM

Quote:

Originally Posted by Al1943 (Post 5417450)
I think ramps and pins are more important for indexed shifting. Friction shifting works fine without.
The ramps and pins help the chain climb from a smaller chainring to a larger chainring. With friction shifting you can over shift and then trim back but with index shifting there needs to be greater accuracy because the derailleur cannot move the chain as far laterally or back up.

Al


"works fine" but shifting under load or any other time is more effortless with ramped and pinned rings.

ed rader

Michel Gagnon 10-09-07 07:06 PM

It depends on what chainrings you have and how you define "good shifting".

Basically, if you have the typical double (53-39 or 48-34 for example), shifting will be quite good without ramped and pinned chainrings, but it will be transparent with ramp and pinned chainrings. On the other hand, if you have cobbled up a really compact wide range double (50-28 on a mountain crankset for example), than the lack of ramps will show.

By "quite good" vs "transparent", I mean that with ramped and pinned chainrings, you will feel confident enough to shift while standing on the pedals, whereas without them, you should ease a bit pressure on the pedals. You'll still be light years ahead of a 1980-style derailleur.

rmfnla 10-10-07 03:37 PM

Quote:

Originally Posted by sch (Post 5416955)
Yes it makes a difference, though only going from smaller to larger chain wheels.
So in a double the largest CW and in a triple the mid and large CW should be pinned
and relieved for best shifting. You don't realize what the pins do til you go back to
your old '70s era bike and discover what you have gained.
A study of the cassette will show all the cogs are pinned as well.
It works.

None of my cassettes have pins.

RockyMtnMerlin 10-10-07 05:32 PM

Quote:

Originally Posted by rmfnla (Post 5430047)
None of my cassettes have pins.

Mine either.


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