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Motorized Cruiser Bicycles The beach cruiser has always been great bicycles to motorize. They just look good with a motor. Use this section to share and discuss about motorizing this classic.

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Old 07-29-2010, 12:27 PM
Beej Beej is offline
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Default 18 To 20 Tooth?

Been reading and I keep coming across posts about changing out the rear sproket on the pedal side to a 20T over the stock 18t? Read you can start easier and get better braking power? Tell me about this please.
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Old 07-29-2010, 12:37 PM
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CoastalCruiser CoastalCruiser is offline
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Default Re: 18 To 20 Tooth?

Yes, you'll get easier pedalling, less top speed if only pedalling. However, it won't effect your braking capability.
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Old 07-29-2010, 01:16 PM
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Default Re: 18 To 20 Tooth?

Yes... like CC said it will make your peddling easier from a dead stop as it lowers your gear ratio by 2 teeth. It will give you a little better braking power ( on a coaster brake, of course) in that you'll have a bit more leverage and it engages quicker because of the larger diameter. On a freewheel type rear cog it will have no effect on your braking whatsoever.

On my bike I dropped from an 18t to a 16t because my front chainring is only a 36t and that was to low of gearing for my taste. I'm also running a freewheel, not a coaster brake. Hope this helps,cheers.
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Old 07-29-2010, 01:36 PM
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Default Re: 18 To 20 Tooth?

i usually run a 36 in the front and an 18 or a 19 in the rear.

in the front, a smaller gear makes it easier to pedal, and in the rear, it's opposite, a larger gear makes it easier.

another plus about having a smaller gear in front is it gives you more room for the motor. and with the added weight, when you do have to pedal, it's not a struggle.

i have an assortment of rear cogs laying around, and since i don't run a tensioner, i find that going from an even number to an odd number of teeth will take out slack from the motor chain by moving the wheel forward or backward slightly. you can do the same with the front sprocket, too.

as far as the braking, scotto's post is more or less correct, but it's affected more by lowering the front sprocket gearing. going from a 44 to a 36 will give you a lot more leverage than going up 2 teeth in the rear. it sounds backwards, but with a smaller front sprocket, you don't have to pedal back as much, so the brake will grab faster.

changing out the rear only by 2 teeth won't really have much of an effect. i mean, there is, but if your brake works now, i wouldn't worry about it.
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