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Old 02-23-2015, 11:58 AM
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SuperDave SuperDave is offline
Motorized Bicycle Elite Member
Join Date: Sep 2011
Location: Panama City Beach, Fl. USA
Posts: 180
Default Re: 2 or 4-stroke

Its cool you ask others for advice about these machines, but in the end it all boils down to personal preferences & abilities.

Mountain bikes often incorporate a suspension for a smoother ride, but lack the visual appeal of a cruiser design. You can look cool or ride in comfort, but you can't have both, not for cheap anyways.

2-strokes offer the best cost efficient solution to motorizing a bicycle. They are very cheap, lightweight, very simple, and offer the best acceleration to weight ratio. They also look much more like their bigger, older motorcycle cousins. They also bear the shame of lowest quality & reliability. A mechanical aptitude is manditory to setup, own & operate a HT ChinaGirl.
Electric motivation is the easiest setup, quiet & environmentally friendly. Its also the slowest, with a limited range, sluggish acceleration, very heavy, and the highest cost of ownership: expensive to buy, expensive to replace batteries.
4-strokes offer a cheaper alternative, with greater reliability over most 2-strokes. However, all things being equal, 4-strokes lack the torque (hill climbing grunt and accelleration) that 2-strokes have. The increased complexity of a 4-stroke also adds to the cost & weight. 4-strokes can have a higher output & top speed when compared to a same sized 2-stroke, but not always.

So in the end it boils down to preferences & skill level. If you don't know the difference between a socket wrench and an allen wrench, take the bus. But if science & math are your thing, then by all means get a ChinaGirl, it takes a clever mind to wrap your head around the chemistry, physics & mathmatics of a 19th century designed powerplant.

And check with the campus you attend, many schools forbid motorized vehicles on their property (except wheelchairs for the disabled). You don't want some trigger happy rent-a-cop to send you and your bike home to momma in a box.
By the holy power of Love, Life & Laughter, I commend you to Go Forth & Be Awesome!
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Old 02-24-2015, 12:13 PM
Scol Scol is offline
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Join Date: Jan 2014
Location: Ireland
Posts: 41
Default Re: 2 or 4-stroke

I after selling my 66cc 2 stroke and buying a 4 stroke 49cc kit I also bought a 32 tooth sprocket. I'm going to fit the standard 44 tooth and see how thing go if I think the engine can hanle the smaller sprocked I'll fit.
My commute is 32 miles round trip so I went with the 4 stroke for greater reliability.
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Old 09-28-2015, 10:48 PM
theisaac theisaac is offline
Motorized Bicycle Newbie
Join Date: Sep 2015
Location: California
Posts: 11
Default Re: 2 or 4-stroke

I was just wondering about this. I have a few questions:

- Is there a big difference between installing a 4-stroke to a 2-stroke? It seems to me that the lack of a handle clutch makes it easier to install. However, not sure if there are other changes.

- "Pull-start", since a 4-stroke can be pull started, can one just remove the pedals and put bars to put one's feet on?

- Centrifugal clutch, how does this work when braking or "coasting"?

- Cost: 4-stroke engines seem more expensive.

- Size: Are 4-stroke engines more expensive?

I'm aiming for a smooth ride, more into comfort.
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Old 09-29-2015, 11:16 PM
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Tyler6357 Tyler6357 is offline
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Join Date: Mar 2012
Location: Santa Barbara, CA
Posts: 730
Default Re: 2 or 4-stroke

One thing nobody can argue is that the 4 stroke motors usually weigh more and are harder to peddle home when a problem happens but many people say they are more reliable as well.
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Old 10-08-2015, 05:08 PM
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Krealitygroup Krealitygroup is offline
Motorized Bicycle Senior Member
Join Date: Mar 2013
Location: Earth
Posts: 78
Default Re: 2 or 4-stroke

I have a four stroke.. It's more comfortable to ride to a gas station and not have to mix gas... They also are more reliable, as I've had a two stroke.. on the same exact frame
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Old 04-20-2016, 05:42 AM
jmason92 jmason92 is offline
Motorized Bicycle Member
Join Date: Apr 2016
Location: Lawton, OK
Posts: 31
Default Re: 2 or 4-stroke

Along with the other benefits of a 4-stroke listed on here, you can just go up to any gas station and refill, so on that end, 4-strokes are recommended. Albeit if you're running a 25-35cc 4-stroke with a Sportster tank or a bigger tank than that, you won't be refilling for a while, and that's just going to and from work, school, the grocer, the wash and dry, wherever you need to go.

....first 'build' will probably be a GX25 or GX35 moped conversion, or any other small 4-stroke moped conversion, to the Adventures 700c that I've been supplementing the bus with, and that moped conversion would replace public transit altogether after getting licensed on my first PTO.

A Briggs 10hp single-cylinder or 20hp opposed-twin board tracker build is yet another idea that is to just stay in my mind for however long is necessary.

inb4 realizing that I necroobumped. ^^;

Last edited by jmason92; 04-20-2016 at 05:54 AM.
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