I got a new set of FSA road cranks for next to nothing and chucked them on. tried 50/16 which is about 84ish doing a short 4km commute this morning and it was fine but couldnt push up the final hill (doubt I could maintain it for too long either)
Next cog down on it is a 38 so might be too small. aiming for about 75-80 ideally
All the qas kids including 15 year old girls run tiny gears and smas the guys on big gears with what you call “legs”
Ok, maybe it’s time to stop swinging our e-peens around in this thread with our massive legs or huge cadences.
lmpc92, to start perhaps grab a 19/20T sprocket and use that with the 50T for 67.5-71". Surly make good ones.
Then after a while if you find you’re spinning out too much of the time, go down to an 19/18T.
If you can’t find a large sprocket or your chain’s too short, 38/15 will give you ~68.5".
^^^ u know i got twig legs right?
in all seriousness, you have 2 options,
you can spin comfortably along in tiny gear. downside is at even the slightest of descents, get ready to do the crazy hampster on crack.
you could avoid said “hampster on crack” but it will cost a bit more effort in your day to day commute, and pobly an acl or two
lol - don’t you read the Courier Mail??? Brisbane cyclists don’t stop for traffic signals and stop signs
53/39 up front, 12-25 on the back. All the gear ratios you need.
Yeah booooyi. A struggle up the hills will rewarded with mack’n down the other side at 60kmh + before ya spin out 
what - where’s the 11???
In his pants
Oh the quandary of a single gear.
another reason for spinning is still having the use of your knees when you’re 40
not if your spinning out down some slight ant mound and a car pulls out in front of you… “LOW gear, no brakes… cant stop, wish i could”…
your not serious.
48/17 and I live at the top of a hill. This is good enough for short steep hills if you are willing to power into them but if you’ve got long steady climbing go smaller. This also seems a good gear for me for city riding (to maintain car-ish speed). trouble comes when you are constantly being overtaken
Ok so now you have your gear sorted I guess you will be doing some bike tags and rides
I commute on 70" 48/18 and ride in bunches on 82" 50/16. 70" is good for cruising in the mid-30s and fine for Gailey Rd and Cemetery Hill. Anything over 40 gets me puffing in short order. 82" is okay for cruising mid-40s but hard work on those sharp pinches. Downhill means fast pedalling with 70km/h at 210rpm on 70" - I haven’t spun out on the 82". You just have to start around 70" and move to what suits your routes and style from there. It will change slightly as you get stronger, too. Rabbit, a singlespeed and fixed-gear cycling calculator, is great.