You have a couple different options. I think the cheapest would be to switch to a compact crankset which would change the front chainrings from 52-39 to 50-34. I'm pretty sure you could do this while still using the same shifter. Changing the front shifter is required if you want to go from a double to a triple, as is changing the front derailleur. If you switch to a compact I'm pretty sure you can keep the same derailleur and shifter.

Another thing you'll want to look out for is the rear derailleur. You currently have a short cage derailleur, and you may need a medium or long cage derailleur when you go with a compact crankset.

I don't think a triple should really be necessary on a 10 speed system. I have triple, but I have an 8 speed cassette. I find in that case the triple is nice because you can still get lots of gear range while still keeping the gears close together, However, on a 10 or 11 speed cassette, this isn't really necessary. I think that switch to a compact crankset is a much better option.

Also, according to This post, the maximum cog size of a short cage Shimano short cage is 27 and the total drivetrain capacity is 29. To use a larger cassette, you would have to switch out the rear derailleur. If you used a compact crankset, you should be probably also replace your rear derailler for a medium cage, as your total capacity would be (50-34) + (27-12) = 31. However, if you changed the cassette to a 12-25, you could get away with not replacing the rear derailleur and still getting a little bit lower gearing, although possibly not enough for your needs.

You'll need to swap out your left (front) shifter and front derailleur to utilize all three chainrings of a triple.

Between the cost of that and the cranks, I think a better option would be to swap out your rear cassette for something with more range. Since you've already got a 12-27 on there, a 12-32 would give you I believe the range you need.

My hunch is that you'd be able to fudge it with your current short cage rear derailleur, but a medium cage mechanism will probably be less hassle in the long run.

Since cassettes are consumables and need to be replaced periodically, this cost of the just rear mechanism is likely significantly less than the shifter, front mechanism, and the crankset.

When you say two lower gears, you presumably have 25 and 27 as the largest gears in your cassette. Does that mean 39/31 would be low enough? If so, the compact with a 34 will get you there, but 34/25 will be too high. Shimano makes a 12/30 10speed cassette in the CS4600 line, which I have coupled to a 50/34 compact. You will be in for a new rear derailleur that way. They also make a 11/32 11speed, but that needs new shifter as well. This might avoid the crankset change, however.

我不會三連冠，這是為什麼這些產品逐漸退出市場的原因。如果您要在陡峭的山坡上攀登並希望降低傳動比，可以考慮改換您的卡帶，也許是環，那麼我建議首先嘗試的是將您的卡帶換成山地自行車卡帶，這可能需要您還將後撥鏈器換成長臂撥鏈器，您將需要一條新的鏈條，但是無論如何無論何時更換卡帶，都應該更改它。如果需要更多，請嘗試將小戒指換成較小的戒指。您也可以通過這種方式省錢，因為您不必更換曲柄或變速桿。

When I made this change 15 years ago, as well as the new triple chain rings I needed to change the bottom bracket - cotterless square taper type - (which needed to be longer to correct the chain line), front derallieur (needs to be able to cope with extra travel and larger difference in chainring sizes) and rear derallieur (needs to be able to cope with larger total difference in teeth).

You will also need to change your shifter to use the new range on the front.

儘管社區中有很多好的答案，但這全都取決於騎手。作為這種情況下的騎手，正確的答案是要堅強起來，只是增強肌肉來爬坡。自從一個多月前發布此問題以來，我能夠進行足夠的培訓，以適應在較高檔位的陡峭山坡上行駛，從而無需更改組件。感謝大家的幫助，為大家投票！