Sprocket/Cog question

[Straight8Dan]

After a lot of reading, I'm still confused about this. I've read in more than one place that your front and rear sprockets should be a 2:1 ratio (i.e... 22t rear cog = 44t chainring/sprocket). I've been looking at a bike that is listed as having a 22t cog and a 46t sprocket so I'm assuming that what I read on the other sites isn't necessarily always true since this bike is stock from the manufacturer. My question is, what does the additional 2 teeth do for you, and would there be a big difference going to a 44t sprocket instead of the 46t?

The other reason I ask is there seems to be WAY more options in 44t sprockets out there, than in 46t.

 

[RustySprockets]

Boiling things down to the bare basics, the bike with the 46 tooth ring will be faster at the same pedaling pace, but slightly more difficult to climb hills. The difference isn't enormous--maybe 5 percent at most.

 

[SSG]

Something like this really comes in handy. http://www.bikecalc.com/gear_inches

 

[deorman]

Depends on wheel size, topography, and rider. 2 to 1 is a little low for me with a common 26", I generally run closer to 2.4 to 1 (ex., 44-18), that would be different in an area with more and longer hills.

http://www.bikecalc.com/gear_inches

 

[Straight8Dan]

Fortunately I don't have any hills around me, so I can use a cruiser style bike 100% of the time without any problems, even if it's only a single speed. If I'm understanding this correctly, because there's only a 5% difference I really won't be able to tell the difference between the 44t and the 46t? If that's the case, I should probably just go with the sprocket I like.

One other question I came across when looking at sprockets is the chain size. I really liked this Profile Inferno sprocket I found, but it says it's for a 3/32" chain instead of 1/8". Would there be a disadvantage going to a 3/32" chain?

 

[deorman]

https://en.wikipedia.org/wiki/Bicycle_chain#Sizes

 

[deorman]

Basically 1/2"x3/32"=10 thru 21spd, 1/2"x1/8"= one spd and internal gear.

 

[Straight8Dan]

Huh... I didn't think profile made any multi gear bikes, but I could be wrong.

 

[deorman]

I'm not familiar with Profile. I have seen some one speed bikes with 3/32", but historically it's not the norm.

 

[Straight8Dan]

Profile is a BMX company. They used to make some pretty good bikes back in the 80's and 90's. They also make some of the coolest sprockets/chainrings I've seen. I've been thinking about using the "Widowmaker" (attached image) on something as well! It's pretty sweet!

 

[deorman]

If you're using a coaster brake hub, 3/32" chain probably won't work, but a 1/8" chain will usually work on a 3/32" sprocket as long as it is not excessively tight.

 

[Straight8Dan]

If you're using a coaster brake hub, 3/32" chain probably won't work, but a 1/8" chain will usually work on a 3/32" sprocket as long as it is not excessively tight.

Really! That I definitely didn't know! There won't be too much play in it?

 

[deorman]

There's play, if it's too tight it may "pop" from one side to the other, but I have seen it done. There was one guy on here who actually ran 1/8" chain on a derailleur set-up with a regular link pressed in because a master link wouldn't work. He claimed it worked fine.

 

[Bicycle808]

Profile Racing is rad, but not as rad as they once were... a lot of BMX has gone to 3/32" chain, but not all of'm. As mentioned above, it's easy to run 1/8" chain on 3/32" sprockets, but not the other way around.

 

[OneHorsePower]

ratio is really something you have to dial in with everybike like deorman said. for example , on my last 700c build i had a 2.75/1 ratio (44x16)

 

[user 15387]

Remember that in addition to gearing, that others have described, you also have fit in the frame. Changing a rear cog or front sprocket may force a change in position of the rear wheel in the rear drop outs and fenders. If you have a close-fitting fender or very small or very vertical rear drops, you run the risk of being unable to accommodate certain gear ratios. If you have longer and more horizontal drops, or more space at the fenders, you can accommodate more gear ratios. Some people will only change ratios in steps of 4 teeth because it keeps the wheel the same place, and they are unable to accommodate more than one rear wheel/axle position in the frame.

 

[horsefarmer]

After a lot of reading, I'm still confused about this. I've read in more than one place that your front and rear sprockets should be a 2:1 ratio (i.e... 22t rear cog = 44t chainring/sprocket). I've been looking at a bike that is listed as having a 22t cog and a 46t sprocket so I'm assuming that what I read on the other sites isn't necessarily always true since this bike is stock from the manufacturer. My question is, what does the additional 2 teeth do for you, and would there be a big difference going to a 44t sprocket instead of the 46t?

The other reason I ask is there seems to be WAY more options in 44t sprockets out there, than in 46t.

Straight answer is smaller front sprocket gives you a lower gear ratio. More pedal revolutions but easier to pedal. Many variables tho - terrain, tire dia and width, seating and bottom bracket position, crank length and your personal preferred cadence. If you have access to other bikes, try them and see what works for you. calculate the gear inches of your preferred rides and then calculate the gear inches of your bike, stock and with the bigger sprocket.
Or just buy the bike and ride it around a while. If you seem to be peddling crazy fast with little effort then fit a larger front sprocket.

 

[Phil Fink]

I also had a 46-22 stock cruiser that I wished to make pedal a bit easier on slight rolling up-hills; (I don't mind coasting on the slight down-hills). I found that 46-24 would not fit the chain, even with addition of a half-link; (original poster may wish to look-up half links). So I ended up switching the front chain wheel with a 44T of similar style, (for a 44-24 gear ratio).
The larger front chain wheels have an additional role of appearance; (few care what the small rear cog looks like. The larger chain wheels have the advantage of more/maximum material condition; bigger area allows for more holes, or just a greater canvas for stylistic patterns.
I found that the large rear cog/sprockets may also affect the chain guard clearances; (what is that rattling sound?).
Lately, I am looking into odd ratios, such as 43-23. Odd toothed sprockets automatically provide for more even wear, (without the aid of a half-link).