sbs z31

So I decided to try fixed yesterday and love it. I keep hearing people say to practice riding a fixed in a parking lot or around the block before getting on the road because it will throw you over the handle bar. I don't think it's a problem as long as you have a front brake and remember you're riding fixed. Rode fixed for three miles and just fell in love with it lol not going back to freewheel. My question is do I really need 165mm cranks? I'm currently using Sugino RD2 172.5mm cranks at the moment and not sure if it is a good idea or worth going with shorter cranks. Any advice(s) will be greatly appreciated and happy thanksgiving to you all!

Nagrom_ 

If you aren't having pedal strike issues and you're comfortable, stick with it.

sbs z31

I guess I'll ride some more and then decide. I'm out of town right now visiting the inlaws and all I think about is riding lol. Hopefully it won't snow/rain this weekend so I can go for a 30mi ride on fixed, still have to learn how to skid and slow down without using my front brake.

hairnet

You're most likely fine unless your frame has a super low BB. I have done it and was tempted to eventually go with 175

LesterOfPuppets

I'd rather get fatter tires than shorter cranks personally but it's a kinda personal choice. (that is assuming pedal strike in corners is bothering you)

I'm just running 170s tho.

sinikl

My concern would be that you may not know you have pedal strike issues til you're hauling ass and lean it in and then BAM. not sure you could simulate that well at low speed in a parking lot to check...

hairnet

Even with a freewheel, that amount of leaning takes practice and skill to execute without having the bike just slip out from under you (been there, done that) otherwise you can just slow a little and continue to pedal through most corners. FWIW, I have only had recurring pedal strike issues with 180 cranks on an average road frame. On a conversion or road geo "track" frame maybe limit the crank but I think a real track frame will let you get away with a lot.

If you don't know how to really corner, and don't kid yourself, then just slow down and go about your business.

LesterOfPuppets

I pedal strike on fw bikes all the time and have never gone down. I had peg strike on a Honda Spree now THAT was scary. My fixed BB is 11" high so have only struck a couple times on it. NBD.


Disclaimer:
Umm, wear your helmet.

Bat56

I like them short and it has nothing to do with pedal strike. Spin.

lhbernhardt

The shorter cranks are an advantage on descents. For a given angular velocity (basically rpm's), your foot will be traveling at different linear velocities (inches per second) depending on how close it is to the center of the circle. Thus, the further away from the bottom bracket spindle your foot is, the faster it has to move for a given crank rpm, because the foot has to travel a greater distance (circumference) to get around the circle.

The tradeoff comes when you're going up the hill. You get more leverage with longer cranks, so you can push a bigger gear. So when you go down that hill, you don't have to spin as fast to go downhill at the same speed as on the smaller gear.

Nevertheless, I use 165's on the road and the track (I'm 6'1" with a 35" inseam). I don't find that they make any difference going uphill, and I can spin faster going downhill. My road fixie has a 60mm bb drop, which is great for riding on a 47-degree indoor velodrome; I don't even come close to striking a pedal. In my mind, fixed gear riding is all about spinning, and the shorter cranks facilitate that.

Luis

cruiserhead

I have 172.5's and 165's. Both are fine, so running what you have is totally fine.
If you feel like changing it up later, go for it.

JohnDThompson 

Short crank arms aren't strictly necessary unless you have problems with pedal strike. This typically happens when taking a corner fast, and the bike is leaned well over. Take it easy on corners until you've learned how fast you can take them. If you find yourself hitting your pedals often, shorter arms will help.

Another area where shorter crank arms help is in spinning, as on long downhills. The shorter arms don't make your knees bend as much so you can sustain a higher cadence, at the cost of slightly lower leverage.

Dannihilator

I had 165's for awhile, but am more comfortable with 172.5's.

sbs z31

Thanks for all the advices guys I really appreciate them!

hairnet

I almost feel dumb for having ridden 165s for so long. Too damn tall

jimmytango

Yeah, man. I ride 172.5, and you're taller than I am.

GENESTARWIND

thats kind of how i feel now, i run 165 omniums after i switched from my schwinns 170's or 172's.. i dont quite like it as much, i noticed a large loss in leverage although i can spin quite well with them i think id rather shoot up to 167s or 170s but i got the omniums w bb for a 100 so...but i did get pedal strike with this frame and the stock cranks quite often, you could see the pedals where just grinded down where i constantly would scrape. god i need a proper track frame with a higher bb so i can run longer cranks.

hamfoh

I run 170s most of the time, 167.5s because of a trade on my everyday bike. I sold a friend a set of 172.5s before and he rides that thing actually on the track without an issue too. You should be fine

Scrodzilla

What frame are you riding? Longer crank arms pose more of a threat on converted road frames (which have a lower BB) but on a "track" frame, you should be ok.

I use 170s on all my bikes except for my Raleigh Conversion.

sbs z31

It's a 75' Schwinn Traveler III 10spd.

Scrodzilla

That frame most likely has a pretty low BB. I'd be careful.

LesterOfPuppets

Especially if ya happened to go from 27x1-3/8" to 700x23, by any chance.

FixedDriveJess

I ride a track bike (track bikes tend to have a higher bottom bracket to prevent striking) and 165mm cranks, and I still manage to strike every once in a blue moon. 170 is the longest I would ever do.

Scrodzilla

No-handed trackstands can be pretty tough on crank arms. You most likely stretched them out from putting too much pressure on them.

FixedDriveJess

Yep.