Help Me Choose the Correct Rear Sprocket

[Daddio]

So, I am getting ready to order my rear sprocket.
Stock lists the gears at 16/39 with 110\80-18 tires 5280 RPM equals 56.2 MPH
Most run 16/37:
Stock lists the gears at 16/37 with 110\80-18 tires 5280 RPM equals 59.3 MPH
My Wheels 90\100-21
My Setting example A 16/40 with 90\100-21 tires 5280 RPM equals 61.8 MPH
My Setting example B 16/41 with 90\100-21 tires 5280 RPM equals 60.3 MPH
My Setting example C 16/42 with 90\100-21 tires 5280 RPM equals 58.8 MPH
My Setting example D 16/43 with 90\100-21 tires 5280 RPM equals 57.5 MPH

I think my bike is a little lighter (or it is just a real low center of gravity), I weigh 180 and I plan on cruising, can't see ever going over 80 with those narrow tires.
It will have Pod filters, and I think I am going to put baffles in as this thing is just too loud!!!

Please tell me your vote: A, B, C or D.

 

[Daddio]

Come on guys...I can't ride for a few months, so I can't get the butt test. I have had 31 views and only four votes.
Help me out...thanks-

 

[vfost]

Come on guys...I can't ride for a few months, so I can't get the butt test. I have had 31 views and only four votes.
Help me out...thanks-

Wont let me vote or i would!


Edit: It helps when you sign in!

 

[redratbike]

i voted 16:42 sacrifice some top end speed for quicker acceleration

 

[Daddio]

RedRatbike, that was my original choice then I read some comments by Houghmade which made me question it a little. I think that my bike is a little lighter than stock and I am a little lighter than Houghmade (no offense Houghmade) that helps 42 makes sense since it is only .5 MPH slower at the same RPM. The weight differential would probably make the MPH a wash.

I do appreciate everyone's help and opinion in making this decision.

 

[drewpy]

I run a 17/41 with 110/90x18

I can can scream it through the gears and red line in top (this is a standard bike BTW) and I weigh 190 lbs

 

[Daddio]

Drewpy, 17/41 is like 16/39 right? I am guessing this is your track bike that you keep up in the r's, wringing it out right?

 

[FUBAR]

really its only 4mph difference and the torque will be minimal, just go with whats avalible
..unless your going on the track

 

[Daddio]

A couple of reasons FUBAR:
1. My experience is that +/- a couple of teeth on any bike completely changes the feel of the bike and a dramatic difference on the bottom and top end.

2. I have to drill out my own sprocket, because the wheels I am running are actually HD knock-off front wheels, so I want to do this once.

The good part is that every tooth count is available, because I will be using an industrial sprocket which will also help sell the vintage look.

Yeah...my bike wasn't really set up for track time, though I wouldn't mind putting it on a velodrome.

Thanks-

 

[FUBAR]

yeah that makes sense, its just different on paper i guess.

Do you have a build thread?, id like to see the wheel setup your fab'n up
and are you runnin a 21" on the front too?

 

[Daddio]

Yeah check it out, Another new guy and a dream at the bottom of the first page

 

[drewpy]

Drewpy, 17/41 is like 16/39 right? I am guessing this is your track bike that you keep up in the r's, wringing it out right?

1 tooth on the front = 3 on rear. that's on my standard XS!
70 mph = 6.5k revs

 

[chkm8]

@drewpy - really? 17/41 gives you 70 mph @ 6.5k rpm? I was thinking about going to 17/37, I may need to rethink.

 

[Joshwuh]

I vote D since my bike seems to have the smoothest ride from 4 - 6k RPM's and if you're mainly cruising around it seems like that would keep you nearest that range. Plus, then you get more acceleration since you don't sound like you need the top end speed.

 

[drewpy]

@drewpy - really? 17/41 gives you 70 mph @ 6.5k rpm? I was thinking about going to 17/37, I may need to rethink.

dont forget you have 6 gears to play with, so 6th can be an overdrive.

with the bike weighing less and light rider I would think 17/37 would work using 6th on the flat highway!

 

[chkm8]

dont forget you have 6 gears to play with, so 6th can be an overdrive.

with the bike weighing less and light rider I would think 17/37 would work using 6th on the flat highway!

lucky for me i'm only 12.5 stone so I should be ok, right? I'll probably just swap out the front first, see how it goes and then decide if I want to change the rear.

 

[Daddio]

Thanks to everyone who voted. I am going with a 42. I am tempted for a 43 buy 42 is a tooth safer.
Thanks again-