Sprocket sizing effect on chain wear

[Overfill]

Looking at a sprocket change with the next chain replacement on my bike. I am looking at two options that offer darn close to the same drive ratio:

1. 17 tooth front sprocket with a 47 tooth rear sprocket
2. 16 tooth front sprocket with a 44 tooth rear sprocket

I recognize that there are chain length differences between these two setups--roughly 3 links different.
I see that the smaller setup has less slung mass.
I am assuming that with less overall teeth and less overall pins/links that the tolerable wear is lower, is that right and distinctly noticeable?
What else might I consider?

 

[UncleDave]

Nope. The longer assembly with the larger front sprocket will wear less.

The smaller the sprocket the more chordal motion gets generated and the harder on the sprocket, chain, and assembly in general.

 

[WobblyElvis]

I was taught that the small the sprocket, more each link pin rotates when going around a sprocket thus increasing wear.

 

[UncleDave]

I was taught that the small the sprocket, more each link pin rotates when going around a sprocket thus increasing wear.

Thats part of it, is as well as more force per tooth, adding teeth reduces the amount of force per tooth.

 

[UncleDave]

This question has been asked for ages by the motorcycle community.

As a broke kid trying to get 10 MPH of top end out of a 125 for a longer track it was always easier to change a front sprocket than a rear one cost wise - until the effect of doing so caught up with you and the chain stretched all the way to limit of the adjuster.

 

[Ride_Red]

You also need to look at how much space there is around the front sprocket. Some bikes may be a tight fit for the larger sprocket.

 

[Overfill]

OK.
The current and stock sprocket setup is a 16T / 50T
I would surmise that the changes to the rear 50T -> 47T and 50T -> 44T are less significant.
The radius change moving from 16T up to 17T is more significant.
I would expect less chain wear than stock on 17/47, and marginally more chain wear than stock on 16/44.
Right track?

 

[KrisZ]

While it’s true that a smaller front sprocket will put more wear on the chain, I highly doubt one tooth difference will have any noticeable effect.

I would pay more attention to the chain slack and keep it on the max allowable deflection, I actually run them even looser. A tight chain will wear out pretty quickly.

 

[barryh]

No question, the larger engine sprocket is best if it fits.

There was always a rule of thumb about the ideal minimum number of teeth a sprocket should have. I think it used to be 19 teeth. Not that manufacturers took much notice. I can remember my Z900 in 1976 having the rather stupid choice of a longer pitch chain than standard which meant the engine sprocket had only 14 teeth. It never made sense as race bikes with vastly more power managed with a standard chain pitch. Anyway the Z900's big hefty chain broke when it was just out of warranty.

 

[BusyLittleShop]

Going by the ratio here is what you're likely looking at...

50/16 =3.12 ratio (stock gearing with base line wear)
47/16 =2.93 ratio (geared higher than stock with more wear)
44/16 =2.75 ratio (geared even higher than stock with more wear)

50/17 =2.94 ratio (geared higher than stock with more wear)
47/17 = 2.76 ratio (geared even higher than stock with more wear)
44/17 =2.56 ratio (geared the highest than stock with more wear)

53/17 =3.11 ratio (equal to stock gearing with less wear)
53/16 =3.31 ratio (geared lower than stock with less wear)

 

[troop]

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[Paco Pena]

I wouldnt think one tooth difference on the front sprocket would be a large increase in wear. If you were dropping down to a 13 or 14 that would probably cause a noticeable difference over time.

Paco