rear sprocket size?

GoldenMotor.com

sprocket size makes difference in speed or torque?

  • bigger sprocket = lower speed

    Votes: 0 0.0%
  • smaller sprocket = more torque

    Votes: 0 0.0%

  • Total voters
    4
  • Poll closed .

fauxmaster

New Member
Jul 3, 2009
1
0
0
florida
im building a trike, it is a 3 speed to the rear stock. the cross shaft that has the 3 speed sprocket will only let me clear a 6 inch max sprocket which will be mounted to directly to the shaft and not the bike spokes... does anyone have any ideas as to what will happen with such a small sprocket mounted to the back, will i be traveling faster but slow to get there or slower but a **** of a lot of torque?brnot
 

Cabinfever1977

New Member
Mar 23, 2009
2,288
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Upstate,NY
you have your poll wrong. you have the torque backwards.
the correct answer is this:
smaller sprocket= less torque/slower acceleration/faster top speed
larger sprocket= more torque/faster acceleration/slower top speed

6" is around the size of a 36t sprocket i think

you will be traveling faster but slow when starting out , with less torque.
 
Last edited:

matt167

New Member
May 20, 2009
420
0
0
usa
a pic to show your issue would be very helpful.. the bigger the sprocket, the more torque you will have, but a reduced top speed.. smaller will be opposite..
 

Cabinfever1977

New Member
Mar 23, 2009
2,288
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Upstate,NY
also it would help if we knew what engine you are using.
if the engine is atleast 1.6hp+ and you can fit a 36t sprocket on there,you should be fine. you might not go up steep hills or take off fast but once you get going, you should be able to fly down the road at some good speeds.
 

matt167

New Member
May 20, 2009
420
0
0
usa
also it would help if we knew what engine you are using.
if the engine is atleast 1.6hp+ and you can fit a 36t sprocket on there,you should be fine. you might not go up steep hills or take off fast but once you get going, you should be able to fly down the road at some good speeds.
got to remember, he has double the rolling force.. 2 rear wheels, full axle and a bit heavier than a bike
 

igore

New Member
Jun 21, 2009
11
0
0
oregon
question
I have a 3 hp 4stroke engine with a 10 tooth drive sprocket driving a 52 tooth wheel sprocket is that about right???
thanks
 

matt167

New Member
May 20, 2009
420
0
0
usa
just reread my post... geared tall unless it's got 30" tires.... on a China, it would be a hill climber with a top speed of about 20, but a 3hp 4 stroke has enough torque for the hills, and really 40 tooth would be more than sufficent
 

Bikeguy Joe

Godfather of Motorized Bicycles
Jan 8, 2008
11,837
252
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up north now
just reread my post... geared tall unless it's got 30" tires.... on a China, it would be a hill climber with a top speed of about 20, but a 3hp 4 stroke has enough torque for the hills, and really 40 tooth would be more than sufficent
Don't forget the china engine has an internal reduction.
 

igore

New Member
Jun 21, 2009
11
0
0
oregon
this is a harbor freight engine 3600 rpm, this 52 tooth sprocket I found at a garage sale. maybe a tooth change on the clutch sprocket
 

matt167

New Member
May 20, 2009
420
0
0
usa
Don't forget the china engine has an internal reduction.
yea, I know, I'm just figuring on what a stock 44 tooth can do, and going from there... as far as the 3hp engine, it'll have about 4 ft/lbs of torque without gear reduction. enough to get up most hills without too much gear
 

xlite

New Member
Jun 18, 2009
735
0
0
ny,ny
this is a harbor freight engine 3600 rpm, this 52 tooth sprocket I found at a garage sale. maybe a tooth change on the clutch sprocket
I can tell you the HF 80cc needs at least 80-90 tooth rear and disable governor to get reasonable top speed.