Off topic: Fixie Advice- Mtbr.com
Results 1 to 6 of 6
  1. #1
    mtbr member
    Reputation:
    Join Date
    Jan 2004
    Posts
    109

    Off topic: Fixie Advice

    Hello all,
    I know that this is a little off topic but I realize that may of us SS freaks ride fixed too. So here goes. I'm gonna take the plunge, buildin a commuter fixed gear, old trek 520 frame, old parts.

    What i need help on is this:

    Ratios
    I ride 34 x 16 on my 26" off-road and 34 x 18 on my monkey but what is ok on a fixie, I like in IL so pretty flat and it is a short commute. I will also use this bike to fart around on the paths and road too as it will be my only skinny tire bike.

    Crank Length
    Shorter or longer? I ride 175 on all of my others, any great reason to change? I need to purchase a crankset for this bike so I can choose my length.

    Thanks in advance,

    Winky
    I'll post pics when I'm done if no one objects (and I can figure out how).

  2. #2
    mtbr member
    Reputation:
    Join Date
    Jul 2005
    Posts
    383

    Good job!

    Quote Originally Posted by Winky
    Hello all,

    Ratios
    I ride 34 x 16 on my 26" off-road and 34 x 18 on my monkey but what is ok on a fixie, I like in IL so pretty flat and it is a short commute. I will also use this bike to fart around on the paths and road too as it will be my only skinny tire bike.

    Crank Length
    Shorter or longer? I ride 175 on all of my others, any great reason to change? I need to purchase a crankset for this bike so I can choose my length.

    .

    Excellent; you'll love fixed-gear commuting!

    Gearing: I use a 46 X 17. It puts me at about 71 gear inches. By comparison, your offroad 26" SS is about a 55. I can accelerate well, climb (almost) everything, and descend all but the steepest hills without bouncing around. Out of fear of spinning out on downhills, I had been using a 16T cog, but I started to get a few knee twinges and was really grunting on some of the uphills. It was unbelieveable what a difference that one-tooth cog change made! I recommend that you shoot for 69 - 75 g.i. and if you can swing a flipflop hub, it's nice to be able to switch it when you get to work if it's mostly uphill one way and downhill the other.

    For crankarms, I'm running 165s. You can probably safely go to a 170, depending on BB height. 175 and up and you risk pedal strike when cornering; remember, that inside crankarm is going to come around no matter how far you're leaning -- and pedal strike on a fixie WILL put you on the ground, unless you have made prior arrangements with God.
    Consider also your pedal choice. You'll learn to take your turns differently on the fixie, swinging out and entering the turn on the outside to avoid braking and leaning, but until then, run something without much width/depth.

    Good luck and enjoy the new ride experience!

  3. #3
    ballbuster
    Reputation: pimpbot's Avatar
    Join Date
    Dec 2003
    Posts
    12,717

    Kinda new myself...

    Quote Originally Posted by Winky
    Hello all,
    I know that this is a little off topic but I realize that may of us SS freaks ride fixed too. So here goes. I'm gonna take the plunge, buildin a commuter fixed gear, old trek 520 frame, old parts.

    What i need help on is this:

    Ratios
    I ride 34 x 16 on my 26" off-road and 34 x 18 on my monkey but what is ok on a fixie, I like in IL so pretty flat and it is a short commute. I will also use this bike to fart around on the paths and road too as it will be my only skinny tire bike.

    Crank Length
    Shorter or longer? I ride 175 on all of my others, any great reason to change? I need to purchase a crankset for this bike so I can choose my length.

    Thanks in advance,

    Winky
    I'll post pics when I'm done if no one objects (and I can figure out how).
    .... but 63 gear inches is a place to start. I ride 63 or so, and it feels a bit tall for my fat arse on the hills of Oakland, CA. I'm still trying to learn to track skid and stuff, tho. I still run brakes on my street fixie.

    You can calculate gear ratios here:

    https://sheldonbrown.com/gears/

    I would say go slightly shorter cranks than you would normally use. I use 175s on mountain, but use 170s on my fixie. I also use 170s on my roadie, but they feel a tad short there.

    Check out https://www.63xc.com for fixie info, as well as the fixie forum on www.roadbikereview.com






  4. #4
    SS Clyde 29er
    Reputation: fire horse's Avatar
    Join Date
    Mar 2004
    Posts
    607

    my thoughts...

    to share with you are:

    RATIOS-there are a couple of diff umm...paths ..hehe of thought on this one:
    --first id say, play around w/ a couple of gear ratios before you settle in on just one. this is why flip/flop hubs are so cool. not only do they come in fixed/free but, also fixed/fixed: Kogswell, Phil Wood, etc. so IF you can afford to put together a solid fixed gear wheel this is the way to go in my opinion. this way you could run a higher gear ratio for flats on the street (gettin yo ass ta work on time), or a lower gear ratio for trails, mud, rain,.. whaterver (or playing on the way home).

    since im on the topic of hubs, make sure you carry the appropriate wrench/tool in your commuter bag/repair kit. some newbies forget this essential item until they get their first flat

    on gear ratios, you can essentially have the same gear inches with a bigger chain ring and bigger rear cog (ex. 46 toothed chainring x 20 cog= 63 gear inches) or smaller combo (37x16=63 gear inches). Essentially these are both the same gear ratio or gear inches. so why bring it up? Depends on you application. if you are going to mostly be on the road, id say go with the bigger combo. why? with a bigger chainring/cog, you pedaling motion tends to feel smoother. with the smaller combo (37x16) the smoothness may not seem so much so less smooth BUT, you are less likely to bash the smaller chain ring against say...a log. soo..the smaller combo is better for running off road!

    i like running a 46x20. you will see people with bigger gear ratios (ex. 46x17) but, for me id rather spin a little more than have to torgue a bigger gear thus saving my knees a little stress.

    CRANKS- id echo what others have said. unless you are going to be climbing hills, OR you have say a size 14+ shoe, 170mm cranks are the way to go. first off you are going for RPMs here. being on a fixie means keeping cadance, esp on downhill descents, so the shorter cranks help make that happen. also, pedal strike, if your commute is on tame streets at moderate speeds you may never have to really worry about this, (ohh did i mention neogoating curbs?) id worry more about learining how to get up and down curbs, bumps, etc. in that dept most of the worry is in your head, you will get skill as you practice.

    TIRES- you may want to go with some good ol cross tires, say in the 32-35c department for soaking up bumps, potholes, and forgiving beginner type mistakes when not avoiding obsitcales or just to be ready for fire road level, off road fun, (say 50-60 psi MAX!).

    BRAKES- if you dont have anyone to impress, one on the front and back is a good idea. yeaa i could tell you some tricks for stopping without breaks but i dont like to encourage dumb ideas and im sure your name aint Bevis or Butthead.

    PEDALS- if you are going to ride a fixie, use clipless pedals so your feet will stay attached to the pedals when you are riding (i think thats the point of it all anyway). nothing looks more silly than a fixie with platform pedals. it says im not committed and im not skilled enough to really be riding this thing, therefore im...a...POSER! besides, if you go into a high RPM spin, platform pedals wont stay connected to your feet and you are going to get your feet cought in the pedal/crank arm blender or you are going to have to lift your feet above your spinning mess below you, upping your center of gravity, and if yuou do it long enough, cause your rear of your bike to start fish-tailing, (this = accident

    NUTRITION- if after a while of trying this grand experiment you find that you are aching in places from torn muscles, strained ligaments/tendons, etc. you may want to, if you arent already, start taking some glucosamine and condrotin joint formula (500mg/day or 1,500mg/day if recovering from an injury). this is provided that what u are experienceing isint bad enough to see a doctor and is simply joint or muscle strain (<<disclaimer). riding a fixie can be way more taxing than riding a singlespeed,and definately takes more skill. anyway, good luck!

  5. #5
    mtbr member
    Reputation: Legbacon's Avatar
    Join Date
    Jan 2004
    Posts
    8,566

    46 x 18/17

    I started 46 x 18 and switched to 46x17 as I got used to it but switched back because I moved to a hillier place. It depends how strong you are vs how hiily your riding is. What ever you decide I recommend a Miche splined carrier and cog. It allows you to swittch cogs by just removing the lockring, no whip required. My LBS suggested it and now I have it on my IRO Mark V, and Kona Explosif w/ENO. As for cranks my Mark V is designed with a higher BB so I get away with 175 cranks and eggbeaters. With a lower BB I would probably let shorter cranks.
    Formerly Travis Bickle

    Team Robot. "modulation is code for “I suck at brake control.” Here’s a free tip: get better."

  6. #6
    "Mr. Britannica"
    Reputation: roadiegonebad's Avatar
    Join Date
    Jan 2004
    Posts
    1,818
    I'm assuimng a Trek 420 is a road bike with 27" or 700c wheels.

    Ratios
    The typical road FG gearing is 65 gear-inches, which translates to 42x17 or 39x16. Of course some go higher, and some go lower.

    Crank Length
    175 is pretty long for a road bike, but you could use them. Typical road cranks are 170 or 172.5. 165 is you really want to spin.

Members who have read this thread: 0

Posting Permissions

  • You may not post new threads
  • You may not post replies
  • You may not post attachments
  • You may not edit your posts
  •  

THE SITE

ABOUT MTBR

VISIT US AT

© Copyright 2019 VerticalScope Inc. All rights reserved.