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Daily Archives: August 13, 2021

Air Kiss CO2 Inflator for Gravel and Road Bikes – A Much Needed Review

I should have posted this review years ago but I never thought to. Here’s what I have to say about the Air Kiss CO2 Inflator: My mother always told me, “If you don’t have anything nice to say, don’t say anything.”

Well…

Anyway, let’s just say, if it wasn’t for my buddy, Chuck saving the day with his most spectacular Lezyne inflator, I’d have been walking home last night. A few of my friends had the Air Kiss inflator and I think I was the last of us to still have one in their saddle bag. I have a Specialized inflator in my tool pack for the Venge that’s worked quite well.

My Skipping Shifting On a Classic Trek 5200… Chain Line, A Fix (Possibly), And The Funniest Idea For A Fix I’ve Ever Heard

[Ed – The information contained in this post is solid, though digging deeper into the problem I eventually came to find that the main culprit to my tale of woe was a bad chainring.]

Vacationing down in Georgia, I had a serious shifting problem. Whenever I was in the small ring and put power to the pedal, say climbing a hill (of which there are many where we ride on vacation), I had the potential to drop the chain into the bottom bracket. If I was careful and didn’t lay down too much power, I’d be okay, but judging what would be acceptable and what would drop the chain, while climbing a hill, was near impossible and certainly frustrating.

Thankfully, weather limited our ability to ride – it rained at night, rendering the morning roads treacherous and too dangerous to bother with on vacation. We stayed active in other ways, swimming and hiking.

It wasn’t until I got home and rode easy, the day after a 100-miler, that I picked up the click while pedaling in the small ring. The rear derailleur was out of adjustment. A full two turns of the barrel adjuster. After months of perfect shifting, I don’t know how it became that bad on the ride down to Georgia, but it was. I thought that would fix the problem. I was wrong.

Later on in the ride, testing it out on a small hill, I skipped the chain again but didn’t drop it off the front ring. I was absolutely flummoxed. New derailleur, fairly new cassette, new chain and a system that shifted magnificently… and I was dropping the chain from the little ring. Then it occurred to me that this had been going on for a while. Years. I thought back and remembered dropping my chain in the same place on the first day of DALMAC every year. I started researching and came up with chain line. Several years ago I changed my 3×9 speed drivetrain to a 2×10 and upgraded the wheels to a 10/11 speed set. Perhaps all the new changes messed up the chain line?

That was the only thing that made sense. The problem was possibly in the crank… but fairly common sense dictated the chainrings needed to move in, toward the bottom bracket. I could move it out, say with a shim, but in was impossible. I resorted to what you’re not supposed to do in this situation and added a half-millimeter shim behind the cassette – and that was on top of the shim that came with my wheels for a 10-speed drivetrain. The chain drop got better, it would still skip under power. I changed the half-millimeter spacer out for a full millimeter. The chain drop stopped altogether but it still skipped in the smaller cogs on the back under climbing pressure, say the four smallest…

Shimming the cassette further is not the answer. I’m running out of space between the lock ring of the cassette and the dropout. That, and you’re not supposed to shim the cassette to fix that issue, anyway – you’re supposed to fix it at the crank, with the set screws and shimming the crank. While I understand that, there was some thought that went into the decision to shim the cassette a bit more that I wanted to touch on. Getting into nitpicking, I have about a turn and a half of play in the rear barrel adjuster before clicking can be heard. Dead center is 3/4s of a turn, then. Well, that’s where the shifting worked best, dead center, but that produced an almost imperceptible skip every now and again that I described earlier in the post. If I turned the barrel adjuster clockwise, the skip would fade away to nothing, but the shifting was slightly compromised… so my thinking was, if the derailleur likes the cassette further out (which is why it wanted the barrel adjuster turned clockwise), then simply move the cassette that way. I should also add, the set screws on both derailleurs were dead nuts, right on – and checked by the pros at the local shop.

Now, that led to one excellent benefit: the drivetrain has never been this quiet. I mean whisper quiet. It’s fantastic. Shifts are smooth and crisp… everything is awesome except for that little skip in the smallest four cogs in the back under power. I just can’t get it to go away completely… and that led to the best advice I’d ever seen on a YouTube video (paraphrasing):

Once you’ve taken everything as far as you can possibly go, accept that your bike just can’t do some things because the chain rubs on the big chainring in the small/second-to-small or small/small combination. If your bike presents issues in a couple of gears, especially in combinations you don’t commonly use anyway, don’t use them like that. Just don’t do that.

I never, and I mean never, use the last two cogs while in the small ring. I also would never climb a hill in the last four on the cassette in the small ring – I have big ring gears for that.

So, with all of that being said, I’ve got to check my thinking with he pros at the shop. I have no idea how this will turn out, but you’ll hear it here when I finally get to the bottom of everything.