lkyjoker86

Hello,
I posted this in Commuting and they suggested to post it here. I have been commuting (14 miles round trip) on my old 1984 Ross convert to a fixed gear (46/16), 700x23 tires, with a front brake. I average about 18/19 mph. I want to go faster! I started two years ago. I pedal as fast and as hard as I can every morning. I have a hill half way through my commute and I conquer it now but when I mash I can feel flex. I use my commute as a workout. My bike is not a typical commuter. It doesn't have fenders, a rack, mirrors, or water bottle carriages. I have the ability to take showers at work and store food there for lunch. With all that being said, I am upgrading to a new setup over the winter so it is ready for spring. Do you think this new setup (Frankenstein) will help in what I am trying to achieve with a little comfort for some occasional longer rides (25 miles)? And will the carbon fork and seat post help with comfort? By the way, I can get all these parts cheap from friends with too much money and indecisive minds. So don't let sticker value sway opinion, please.

I was thinking of upping my chain ring to a 48t

Frame - Leader 721
Fork - I803 CF
Seat post - Origin8 CF
Brooks - Cambium C15 (from current bike)
Stem - Origin8 (from current bike)
Bars - Crew bullhorns (from current bike)
Crank - Eighthinch courier crank 165mm (from current bike)
BB, rear cog - Eightinch
Wheels - Mavic Ellipse 20h front/rear
Tires - 23's (don't know yet)
Pedals - IDK but they are metal toe clips with straps (from current bike)

IFPCL

if you're getting all those new parts you might as well throw in a couple hundred for a cheap alu or steel frame with track geometry.

GhostSS

A carbon fork will make more of a difference with vibration dampening than a carbon seatpost. Also drop handlebars would provide better aerodynamic potential than bullhorns. If you have to go faster, think about changing up your gear ratio with your cog as well. I was running a 53x16t at 87 gear inches for a while and I quite liked it on the flats and learned to put power down from a stop.

If you REALLY ACTUALLY want to go faster you'd be better off getting a road bike.

Leader 721's are aluminum with track geo brah.

lkyjoker86

Thanks for your input. I would like to use drops but I have a recurring back injury I find it hard to get into the drops. I would get a road bike but these parts are what I have available to me and are really cheap, really. All the parts/components are second hand.

Kindaslow

Cheap road bike, scooter, motorcycle, ....

hardboiled718

If you can spin it efficiently the 48t chain ring will do more to increase your speed than most of the other stuff you plan on buying. Or drop a tooth on the rear cog, it's cheaper.
Do you have a lot of traffic? It's hard to increase average/top speed if you have to slow down at every light and keep an eye on cars and potholes, etc. If you got a lot of straight aways with minimal traffic the larger ratio will work well.

lkyjoker86

I have almost no traffic in the morning and only one stop light. During my lunch once/twice a week I ride around the compound. It is a 9.5 mile ride with almost no cars with no lights/stops. Pretty flat. The way has some traffic but no urban by any means.

hardboiled718

^ Definitely try gearing up then. Also you could just work with what you got and practice spinning faster. Since you want to use your ride as a workout, try sprints and stuff.

lkyjoker86

The chain ring and cog sound good to me. Does anyone use a 54/16, 48/16, that has used a 46/16 in the past? If so how much of a difference?

john4789

First off, the motor is the most important thing. Are you riding through the winter? I'm not sure based on your post. Riding more and cross training will probably do more than the upgrades. That being said upgrades are fine.

You are suggesting a 48/16 combo. This is probably too high for your speed. The goal should be to ride around 90rpm at your cruising speed. For 48/16 this would be 21.1 mph according to sheldon. If you are riding 18.5mph now that would require about 30% more power which is a big number. I think your gears are fine, but you should learn to "spin" if you want to go faster.
Sheldon Brown's Bicycle Gear Calculator

GhostSS

Cadence is self selected, his goal shouldn't be anything if he's not racing. 48x16 isn't that big. I cruised at 80 rpm at 20 mph just fine. Also I'm no physics professor, but I don't think an roughly 2 mph increase is a 30% increase in effort. EDIT:There were some discussions in the past with those watt calculators regarding sustained effort and accuracy of the calculator. Either I'm averaging 340+ watts on my daily rides and I'm stronger than I thought, or there some real world variables that aren't being accounted for.

john4789

I agree with you completely, to each their own.

My only point is that wisdom would dictate that you should spin and keep your effort levels as aerobic as possible, so that each days performance is similar. If mashing you might have a couple fast days but lots of not great days. Over the long term spinning wins, which means 90rpm plus. This is my advice but people are free to do as they wish, that's OK. When i first started to ride SSFG I thought i push a much, much, higher gear. Years in not so much.

The 30% figure comes from the squared ratio of velocity, as wind resistance becomes the dominant issue above 15mph.

hohum

+1 for not spinning. Not everyone rides for aerobic exercise. Some just want to get places.

I personally wish I lived somewhere flatter so I could go to a slightly higher ratio.

lkyjoker86

I do not ride through the winter but this year I am going to spin on a stand in my heated garage. With my new set up I should be under 20lbs from my 24lbs bike I have now. So this will have no effect on what I put out, speed an cadence wise?

hohum

The size of your tires slightly affects your ratio. But the weight of your bike doesn't mean anything.

john4789

Speed at 20mph and greater is about air resistance, not so much weight (rolling resistance). Unless you are commuting on hills, the weight is not the issue and will only slightly change the result due to higher acceleration but not top end speed. If you are trying to upgrade for speed beyond 20mph, on flat terrain, think about aerodynamics, not weight.

Do you use panniers? Does your bag hang wide of your torso? What type of clothing (tight/baggy)? These will make more difference above 20mph.

IFPCL

Lol I misread that and thought he was putting all those parts on the Ross conversion

hardboiled718

if you're on a 46, try the 48 before jumping to a 54. try to keep the cadence you currently spin at or improve it if you can.

also weight only really matters for accelerations or climbs, even then you're only talking about a few pounds so don't sweat it.

GhostSS

I stand corrected on those figures, since I used to be a aero weenie I should've known better.

TejanoTrackie 

Having a light, stiff, lively bike is fun regardless of the potential performance gains. It will encourage you to ride harder, which in general will make you fitter. It's more a matter of feeling good about your commute and being a happier person. It looks like what you've spec'd should result in what you want. Unless you want to get involved in competition, don't worry too much about watts, average speed etc, and just do it.

lkyjoker86

Thank you

seau grateau

Leader geo is a little weird because they have steep angles but long wheelbases. I could never get really comfortable on mine, though it was probably a combination of fit issues, frame geometry (steep 75.5 degree seat tube), and an aluminum fork. If you're going to buy one, make sure to take accurate measurements and buy the right top tube length.

ufbeans

Commute faster = low rider weight + low wheelset weight + low rolling resistance tires pumped up high/ how many red lights you run.

TenSpeedV2

Running red lights increases your chances of commuting to the hospital in an ambulance or the morgue in in the back of a wagon faster. You choose.

ufbeans

There's running red lights like you're in a Macaframa video and then there is the slow down first and then accelerate into a sprint red light running. Bikes running red lights is common practice here/