Cranks: 170mm vs 175mm

[jbird]

Does anyone have an opinion on 170mm cranks vs 175mm? I hear some trials riders use shorter cranks to decrease the distance of rotation during engagement. I can see where that with a CK hub would be interesting, assuming it's true.

I'm about 5'10" (if that makes any difference) and want to buy new cranks. I'm more of a street trials rider that likes to use a 22t chainring and 17/18 in the back. I'd like to reduce slack in engagement, but also recognize torque with longer cranks.

[vaughn]

If you've never run 175s you should try them out and see if you like them. It's not a huge difference. Most people settle on 170s eventually but you may make good use of the extra torque with that gearing. You'll also be able to rest on your pedal on more things.

More people use 170s than 175s though.

>Probably no help whatsoever

[jackflash]

im more of a street rider, i originially had 175s then got 170s when i finally got good cranks, its hardly any different, i think i like it a bit better but it doesnt really matter, dont go out and get new cranks just for length. i would suggest you get a bigger cog in the back, like a 19 tooth, 22-18/17 is a bit of a high gear for trials

[vaughn]

it's all about style...I run a 22/16 (i think, or 17...not sure) But I still don't know how to front touch so probably shouldn't listen to me.

[jbird]

I run 175's now, but need another pair of cranks for a second bike. So I thought trying 170s might be worth it. I'm only interested in 170s if most trials riders agree that 170s are an advantage in some way. 175s are a good fit, but I like to experiment. Since I need new cranks for another bike, I'm just contemplating if it's worth trying 170s. 22/19 just seems overly responsive (at this point). I can only gap about 4.5' from a stand still right now. I need more work on the body talk. I'd have to say I'm putting too much emphasis on the pedal torque and not enough on body motion. I'll get there.

Thanks for the input so far. I'll take more if you have it.

[carnagr]

Honestly the gapping 4.5' probably has a lot to do with the damned hard ratio. Try a bike with a normal ratio and you'll go up a foot easy. The problem with the high gear is that you cannot put body language into it when it's that high - you'll just fall flat on your face.

[DRUM]

22/18 is fine for trials, i rode that for my first year. Especially with 175's it is definetly rideable.

Ithink you should stay with 175. The less things you have to get used to when swapping bikes the better. The differences between them are neglible

[jbird]

carnagr, what is a normal ratio..22/19, something else? 22/18 just feels better now, but that may change slightly as my skills improve. I watch trials videos and it seems like most guys are barely "kicking" when gapping yet their still doing monster gaps. If they're running gearing like 22/19 (or even 22/18 for that matter) then that tells me I need to focus on body language a lot more.

DRUM, I appreciate your insight and kind of agree with it, but I think I'll try the 170s anyway. Mean Todd at WebCyclery says he sells more 170 for trials than any other size, and I would like to get a little tighter engagement. So, I'll try them and let everyone know what I think the results are. I don't compete, I just ride for the fun, so it's not a critical issue. We'll see if I wasted $ or not.

Thanks for the input!

[hasa2006]

i m using 170mm crank wit 22T/18T. i tink there is no much problem between 170mm n 175mm. But i used 175mm crank last time.

[eturt9]

22-19 is great. 22-18 is good too, especially if doing mostly street and gives a little more explosion for faster street moves. having 170 vs 175 cranks shouldn't make a huge difference.. definately wont make much of a difference in gap distance. If you running a CK or white industries will help with that quick engagement short pedal stroke you were talking about. Essentially having a shorter crank will also help slightly but i htink most run them because.. thats just what size most trials cranks are... or/and you get a little better clearance.

If you're changning the cranks purely because you think the size differnce will help, i wouldn't get them.. If your getting new ones because you need some, try some 170's. By your first post, i interpreted that you don't run a king. So if your lookign to spend some money, get that over the cranks.

[carnagr]

carnagr, what is a normal ratio..22/19, something else? 22/18 just feels better now, but that may change slightly as my skills improve. I watch trials videos and it seems like most guys are barely "kicking" when gapping yet their still doing monster gaps. If they're running gearing like 22/19 (or even 22/18 for that matter) then that tells me I need to focus on body language a lot more.

DRUM, I appreciate your insight and kind of agree with it, but I think I'll try the 170s anyway. Mean Todd at WebCyclery says he sells more 170 for trials than any other size, and I would like to get a little tighter engagement. So, I'll try them and let everyone know what I think the results are. I don't compete, I just ride for the fun, so it's not a critical issue. We'll see if I wasted $ or not.

Thanks for the input!

With 175's I guess 22-18 wouldn't be too bad. The thing is, they may not be kicking far, but its not about the distance you kick, but about the explosion. Trials is all about accelerating as fast as possible, and the lower ratio allows you to get a really fast, yet still powerful kick in.