Large chainring pins
 

Lately I have had some shifting problems. I cut my ride short after I dropped my chain while shifting to the large ring (by mistake, on an uphill). I put the bike on the stand and eventually realized, when cross-chained on the small-small front-rear cogs, that the chain was getting hung up on (only) one of the pins on the large cog. (These, along with ramps, supposedly facilitate shifting up to the large chainring.)

Thinking that this might be caused by a bent chainring, I was trying to psych myself up to bending it back when I noticed the pin itself was not flush with the chain-ring. The "nail head" was hanging out a little, and I managed to gently coax it back into place by squeezing it with a vice grip wrench.

Then I got to thinking -- is there any reason one of the pins should protrude more than all the others? Has anyone else run into this issue?

It is a White Industries crank/chainring, FWIW.

Well if you were able to move it perhaps your chain can move it also. I would suggest a chat with White Industries, maybe this is a warranty issue. Perhaps some thin (wicking grade) cyanoacrylic glue might help keep it in position.

Of course cross-chaining into small-small is kind of poor form...

Well, this was for diagnostic purposes (but I am guilty of poor form as well), and it was the only way for me to figure out what was going on.

I think you are right. It might be worth asking them about it. I don't think I could bring myself to ask for a warranty replacement.

I'm having a similar problem with a IRD Defiant. I think I'm tracing mine to a displaced rear triangle. My chain deflection in small-small is greater on this bike than on my other bikes with 46/30. I think the wheel hub is displaced toward the drive side. I balanced the position of the rim and tire by dishing the rim away from the drive side by about 3 mm, but I neglected to consider shimming the hub to align the rear chainline with the front chainline. I'm not sure how to do that for a White Industries hub. Adding a mm on the drive side and subtracting one on the NDS would probably do the trick.

Press-fit parts are supposed to stay put in service; if they don't that would certainly be a manufacturing defect. I woulds expect that a high-end manufacturer like White Industries would stand by their product; their stuff carries a top-shelf price, the quality and reliability should be held to the same standard. Of course it is your call.

If it keeps doing it, I agree. If all that was needed is a squeeze on the vice grip once ever few years, then I wouldn't bother.

Maybe even think of staking the edges of the pin. Press it together, then use a hardened steel punch and hammer to deform the outside of the pin so it doesn't slip out.

Modern rings with their varying tooth profiles and lift pins are notoriously "un true". So many stamping steps in manufacturing to maintain flat/straightness. That a lift pin is slightly off is no surprise. If the pin is still solid in the ring (an easy thing to confirm with needle nose pliers) then I would attack it's standoffness with possible grinding of the end. If it's loose in the ring then replace the ring, or live with it. And this pin catching is but one more cost for the current designs we all lustfully suck up to. Andy

I've had this happen on a couple of my bikes, I believe both Shimano rings. I just filed them down a bit and all good.

Being a part that was pressed, crimped, or swaged into place onto an aluminum chainring, it was already cold-set once. Aluminum likes being cold-set far less than steel, even hardened steels like 753, 953, Nivachrome, and OX-Plat. After you have re-crimped this a few times or squished it once really good, the aluminum is likely seriously weakened. If you are squishing a steel or stainless steel pin, you're not likely to make much progress in reshaping that part.

For my bike, my first step is to pull the rear wheel and see if I have a shim between the cassette and the freehub. Also I need to look at whether I can disassemble the axle (it's a White Industries Speedy) and adjust the shimming. I'll also check the installed chainring to see if it spins true, and if a simple gentle cold-set can help. Then try to shim the BB. Those are the simple things. I'm reluctant to have the rear triangles cold-set.

I am fairly confident I just pushed the pin further into the hole a fraction of a mm and didn't deform anything.

If all else fails, I just bought a $150 Shimano 46/30T GRX crank as a backup. (If this shifts smoother than the White Industries crank, the WI crank will become a very expensive spare part.)