is it more difficult to put engine on 21 gear bike than 0 gear bike?

[daveet66]

i had friend put my first kit together he said i needed a bike with no gears since then i put another engine on myself but didnt mess with the sprockets! i have a aluminam 21 speed bike some guy gave me and was wondering if i would be able to switch my kit over or dont waste my time! thanks this site is awesome

 

[Tyler6357]

Certainly you can, unless you are using a shift kit, the gears will only work on the peddle side.

 

[The_Aleman]

I feel that it's easier to put a kit on a geared bike than a single-speed. For one, single-speed bikes usually have a coaster brake, which has an index arm to allow the brake to work. This arm almost always has to come off the rear wheel to install the sprocket. Some people find an additional hurdle to jump with this, the lever may need to be tweaked to clear the sprocket or the sprocket needs it's center enlarged to clear the hub for install.

Also, geared bikes almost always have better wheels and brakes than single-speed. Single-speed bikes aren't equipped for some of the activities that geared bikes are.

 

[CrazyDan]

Geared bikes tend to be made for higher speeds and already have brakes up to the task of basic build motorized bikes. There is usually more clearance for the drive chain, and more often than not, a front suspension. Single speed bikes really weren't designed for high speed stability or stopping power. You can change steering geometry and upgrade a single speed bike to be more stable/reliable, but it tends to end up more expensive than if you bought a good bike to begin with that has all the qualities you are looking for.

 

[Tyler6357]

Geared bikes tend to be made for higher speeds and already have brakes up to the task of basic build motorized bikes. There is usually more clearance for the drive chain, and more often than not, a front suspension. Single speed bikes really weren't designed for high speed stability or stopping power. You can change steering geometry and upgrade a single speed bike to be more stable/reliable, but it tends to end up more expensive than if you bought a good bike to begin with that has all the qualities you are looking for.

I agree, my Peugeot is an late 80s steel frame mountain bike, 18 speed, with really good cantilever brakes and even though they are rim brakes they work just as good as disc brakes and they never wear out.

 

[Sidewinder Jerry]

First of all unless this is some of these newer versions of bikes out you probably don't have a bike with 21 non redundant gear ratios.

What you probably have is a 3x7. That's 3 chainrings up front and 7 cogs on a rear freewheel. The 3x7 gets shifted like this lowest to highest gear ratio 1(1-4), 2(2-5), 3(4-7) for 12 non redundant ratios. Entering an incline at a slow speed 1(1-4). Level ground comfort riding 2(2-5). Declines and level ground sprinting 3(4-7). You should be in a gear where you can comfortably maintain a cadence (crank rpm) of 70-90.

You can buy a bicycle computer with a cadence meter on it off of eBay for less than $25. If a gear is too hard or to easy to comfortably maintain a cadence of 70-90, it means you're in the wrong gear.

Use a starting gear. For stops going up inclines be in 1(1) before stopping and use that as a starting gear. For all other stops use 2(2) as a starting gear.

I'd also personally advise replacing the rear stock axle with a cromolly axle. Freewheel axles are prone to bending and breaking.

[1] The big advantage to a multi speed bike over a single speed is you can use an easy to pedal ratio to bump start a 2 stroke engine. With a single speed you got what you got.

[2] You can run a smaller rear wheel engine driven sprocket for a higher top end speed. Then you can use the low pedal gears to leg assist more when climbing hills.

[3] The other big advantage is if you can't use your engine and live where there's hills a multi geared bike will be better to get you back home.

 

[JerboaJohn]

I like a simplistic 7 speed. i really only use 4 of them when motoring to help on hills. 2x5 or 2x6 is plenty for almost any situation pedaling, and if you have a motor, youll probably never use more than 6 or 7 ratios.

I always think a 1x8 would be great for a shift kit

 

[CrazyDan]

I always think a 1x8 would be great for a shift kit

I tried a 1x7 and the chainline gets too far off, just jumps teeth when it gets to extremes under power. I think a 5 speed is the most gears you want with a derailleur.

 

[extremeodd]

Multiple gears front and rear are fine, I wish my Huffy Parkside had some more/higher gears. Once I hit 20+ my 1x7 becomes entirely useless. It is nice to have the granny gears to get rolling quicker at stop lights. The only issue I could see is on some bike frames the front gearset can occupy part of the same area the motor sits.

 

[The_Aleman]

I've run a 1x7 pedal on all my chinagirl bikes, the same 11-34 Shimano MegaRange set. The 11T 7th gear is real nice when paired with a >46T crank sprocket. I love a 52-11 for pedaling over 20MPH, at 100 cadence that's 37MPH with 26" wheel. I never really used the first 2 gears (34, 28)