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Sprocket Swapping... What's the right way?

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Hypothetical: Let's say my Husky came stock @ 50:13 rear-to-c/s and, after finding it to be too low-geared for highway riding, I decided to re-gear closer to 3.5:1.

If I put a 46T on the rear to go with the stock 13T c/s I'd end up with 3.54:1. Or I could put a 14T c/s up front to go with the stock 50T rear and end up with with 3.57:1. Almost the same exact ratios are derived from two different approaches. In another gearing example, 49:15 is almost the same ratio as 46:14, but something tells me the ramifications would not be the same.

Given equal final drive ratios, what is the rule of thumb for choosing compatible sprockets? What are the most important things to consider beyond just the eventual final drive gear ratio? Wouldn't the internal gearing and intrinsic engine character for a particular bike suggest an optimum final gearing setup?

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From what I've been told is that you don't want to go too small on the front sprocket 12 or 13 is the smallest depending on what chain size because this causes more wear on the chain. I went with swapping the front sprocket and taking or adding slack with the chain adjusters so that I can swap ratio's easily back to stock for different uses.

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First, chose the gearing desired to get the top-end speed or low-end speed/response you want. This will usually be in the form of a small change from your existing sprockets, for instance you may want to go up or down on the front sprocket one or two teeth or on the rear one to four teeth. Calculate the ratio between the sprockets based on the number of teeth on each; most riders use rear/front but some use front/rear. This will give you the desired gear ratio. Then adjust the sprocket sizes while maintaining the desired ratio based on the following:

Changing the front sprocket is cheaper.

Don't go too small on the front, the smaller diameter will wear the sprocket faster.

Don't go too big on the back so as to interfere with the chain guide.

Larger rear sprockets may require a longer chain, or at a minimum, sliding the rear wheel forward. Moving the rear wheel forward will help with turning but may add instability at high speed.

Conversely, smaller rear sprockets may require that you shorten the chain, or at a minimum, slide the rear wheel back. Sliding the rear wheel back will slow the turning but will add high-speed stability.

Changing the front sprocket one tooth either way has very little effect on wheelbase (one half the chain pitch, usually 5/8 div 2 = 5/16) and often does not require changing the chain. There are exception (aren't there always).

Regardless of the above, a given ratio looks to the engine exactly like the same ratio with different size sprockets. If the ratio is the same, the engine doesn't know how large/small the respective sprockets are. It's not intuitive; it's physics. Of course, with very large sprockets and very high speeds, the whole system will be subject to momentum and centripetal forces considerations, but motorcycles do not operate in this realm.

Is there an ideal sprocket ratio? Yep. It's the one that gives you the best overall response for your style of riding on the terrain you ride. The manufacturer engineers pick a ratio that takes into consideration speed and torque so the engine can move the motorcycle in a manner that is acceptable to the expected purchaser - the target consumer. Well, we're all different and all want different performance. Choose what you want and change your bike if necessary, then enjoy the ride. 👍

At least this is what I've been told by others more knowledgeable than I :worthy:

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Best to use the largest diameter gearing. As stated earlier it will place less force on the chain resulting in less wear. Another benifit would be less rolling resistence as the chain doesn't have to bend or flex as far.

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