One of the questions we hear a lot is what rear gear is appropriate for your bike. So, here’s a short tutorial on what’s available, what the costs are, and what gear ratio you might want to use on your bike.
Gears and more gears...we offer gears in 26T (the stock configuration), 28T (the one I use), 30T, 33T, and 35T
Standard equipment on a CSC motorcycle is a 16T (the “T” stands for “tooth”) on the countershaft sprocket, and a 26T gear on the rear wheel. The countershaft sprocket is the drive sprocket that comes out of the engine/transmission case (it’s on the left side of the bike), and the rear wheel sprocket is on the, well, rear wheel. By changing these sprockets we can adjust a lot about how the motorcycle operates, like gas mileage, top speed, acceleration, and hill climbing ability. The 16T/26T stock configuration gives a good balance for all of these factors, with a nod toward maximizing fuel economy.
The countershaft sprocket on the left (stock is a 16T gear), and the rear drive sprocket (shown on the right)
Hwy 58 across the San Andreas Fault in central California...perhaps the perfect place to attempt 173 mph, but not for this boy!
Here’s some more good stuff to consider. Normally, a higher gear ratio gives a higher top speed and better fuel economy (but less acceleration), while a lower gear ratio gives a lower top speed and reduced fuel mileage (but better acceleration). The key word here is normally, and we need to recognize that there are limits to what you can get in terms of more top speed by going to higher gearing. The principal factor is where the engine is in its powerband as the vehicle approaches its top speed. It’s possible (and common, actually) for many performance vehicles to be geared so high for fuel economy that they can’t reach the engine’s rpm limit in top gear. Here’s a pretty cool example: My Z-06, which is a marvelously engineered automobile, has 405 hp, gets 28 mpg on the freeway (phenomenally good fuel economy, a real tribute to the Chevy engineers), and has a top end of 173 mph! But it won’t see 173 mph in 6th gear. You have to downshift to 5th to see the top end (I’ve never explored the upper limits in this car…all this is what Chevy has in the owner’s manual).
A gear ratio chart...the stock setup is in the top row
So what’s all this mean to us? For most of us, if fuel economy is your dominant concern and if you are a lighter person, stick with the stock 16T/26T gearing. If you want a little more giddy-up from your CSC motorcycle, you might want to consider a lower gear ratio. I weigh a little over 200 pounds and I ride with the 28T rear gear on mine (the bike still delivers over 80 mpg, and the improved performance in the hills with this slightly lower gearing is amazing). Another thing I found that kind of surprised me is that I actually gained a bit on the top end when I went to the lower gearing. That’s because the lower gearing allows my CSC bike to get into its powerband and overcome aerodynamic drag in 5th gear at higher speeds (it’s like downshifting the Corvette to see that rumored 173 mph).
Big John, who made me look slow in Baja
My buddy John Welker weighs around 260, and he used the 30T sprocket on his CSC when we did the Baja trip. To my surprise, even though I’m about 50 pounds lighter than John, he could out-accelerate me and he had more top end than I did. Again, it’s all a function of getting the 150cc motor up into its powerband. And for what’s it worth, when we stopped for gasoline south of the border, John’s bike and mine both took the same amount at each stop. Go figure.
We also offer a 33T and an 35T rear sprocket. One of our riders used to weigh about 350 pounds (yep, 350 pounds…he was our “full figured” rider), and he rode with the 33T rear sprocket. The bike performed just fine.
There’s no magic formula that equates rider weight to what sprocket you should use. You need to consider what you want (fuel economy, top end, performance charging up hills in the mountains, your weight, etc.). The stuff above gives you an idea of what you might factor into your considerations.
Oh, and if you want a different sprocket, you need to get a new chain, too. The bigger sprockets necessitate longer chains. We’ll sell you a new sprocket for $44.95, and the chain is $19.95. If you buy a new bike, you can tell us what size sprocket you want, and we’ll install it for you right here at the factory. And if you’re not sure, just give us a call and we can talk about it.
Lupe says hi!
Okay, enough about gear ratios for a bit…a lot of other cool things that are happening in our world,too. With the advent of great weather, the Military Series going full tilt, more dealers joining the CSC family, our advertising, and our incredibly-successful Affiliate Program, things are indeed hopping. I was out in the shop this morning shooting a few photos, and I grabbed one of Lupe. Lupe puts the final touches on every bike that goes out of here, and that’s one of many reasons we get so many compliments.
I also grabbed a shot of one of the latest Military Series bikes, too. This one has our spotlights, a rack, and an awesome OD green military paint scheme. Maybe it’s just me remembering how much fun I had 40 years ago playing Army. Or maybe it’s trendy. I don’t know. Whatever it is, these green machines are way cool. The OD green bike is cool, and so is our Desert Camo bike. Take a look at this OD green Military Series bike and tell me what you think. I think I’m jealous…
The Military Series, in OD green...a very distinctive motorcycle
Just as I was finishing this blog a few minutes ago, Steve came over to my desk. “How you feelin’?” he asked. “I’m okay,” I said.
“Feel like riding yet?” Steve asked…
Hey, he’s the boss…
But that’s a story for tomorrow. Stay tuned, boys and girls, for some really cool photos, including one of an absolutely stunning Mustang that’s worth over a million dollars. Yep, you read it right…a Mustang that goes for over a million bucks.
Stop by the blog tomorrow. You won’t be disappointed.
I promise.
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