Best sprocket size for trail bike

Andrew1234

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What is the best sprocket size for a 50cc motorized bike is it a 48 tooth or 54 or any other sprockets I am open to any sizes
 

DAMIEN1307

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What is the best sprocket size for a 50cc motorized bike is it a 48 tooth or 54 or any other sprockets I am open to any sizes
Depends on what kinda riding you like to do...street or off road, more speed or more torque, hilly conditions or flat conditions, etc. etc. etc., You get the idea...lol.
 

Andrew1234

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Depends on what kinda riding you like to do...street or off road, more speed or more torque, hilly conditions or flat conditions, etc. etc. etc., You get the idea...lol.
im going to be doing jumps and lots of dirt up hill i need to keep up with surron dirt bikes because thats what my friends so i was thinking a 54 for a little bit of speed but a lot more torque then a 44 tooth sprocket
 

ImpulseRocket

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im going to be doing jumps and lots of dirt up hill i need to keep up with surron dirt bikes because thats what my friends so i was thinking a 54 for a little bit of speed but a lot more torque then a 44 tooth sprocket
You might be fighting a losing battle trying to keep up with a surron for multiple reasons.
 

ImpulseRocket

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Just to expand on my previous statement now that I have some time.

A Surron makes 6kw in stock form, that's 8hp. It also has the benefit of electric motor torque, which is basically instant. Your 50cc on the best of days is probably 1.5hp, maybe 2 if you have done some work to it.

The Surron has a lot of suspension under it as well. Not sure what kind of bike you have, but even the best mountain bikes out there with full suspension would be envious of a Surron.
 

Andrew1234

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Just to expand on my previous statement now that I have some time.

A Surron makes 6kw in stock form, that's 8hp. It also has the benefit of electric motor torque, which is basically instant. Your 50cc on the best of days is probably 1.5hp, maybe 2 if you have done some work to it.

The Surron has a lot of suspension under it as well. Not sure what kind of bike you have, but even the best mountain bikes out there with full suspension would be envious of a Surron.
I’ve raced them with my main bike that I took a Dino on and it made 12 hp and it beat them but yet again that Engine is heavily modified and not a trail bike
 

Andrew1234

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Just to expand on my previous statement now that I have some time.

A Surron makes 6kw in stock form, that's 8hp. It also has the benefit of electric motor torque, which is basically instant. Your 50cc on the best of days is probably 1.5hp, maybe 2 if you have done some work to it.

The Surron has a lot of suspension under it as well. Not sure what kind of bike you have, but even the best mountain bikes out there with full suspension would be envious of a Surron.
I just have a mountain bike with front suspension
 

Mc2Stroke

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Im all for you trying to make a DIY “trail bike” and dirt jumps are always fun but…. If you’re really going to go try that stuff then be aware that

1) a mountain bike was not designed to support an engine inside it’s frame while doing extreme off-road things ( I don’t know what kind of bike you have, a high end bike or a cheap Walmart bike) either way that’s going to be a lot of stress on the frame especially if it’s the latter. ( you may get away with small jumps and light off-roading but don’t go to big).

2) depending on how fast/ big the jumps you’re hitting are and how rough the trails your planning to ride on may be, even with a front “suspension” you will be putting a lot of force and vibration into the engine mounts/ mounting points. It’s possible to break a stud or completely crack the mounts on the engine case or the thin metal strap thats holding it to the bike. You can even crack or dent the frame.

(the best thing to do would be to mount the engine to a flat welded on plate with high grade bolts, I’ll try and find pictures if you don’t know what I’m talking about)
** take into account your weight plus the weight of the engine is now going to be coming down on this bike.

3) These engine kits were not designed to build a “dirt bike” nothing that is part of your bike being motorized was meant for what you want to do. I’m not saying it’s not possible or that you shouldn’t do it, just be aware you’ll probably break stuff.

(maybe I’m getting the wrong impression, but it sounds like you want to do “dirt bike” activities like your buddy with the Surron…I’m sure you want to one up him as you already challenged him to/ won a race on your mini bike and now you probably want to hit bigger jumps than them and try to whoop em on the trails too).

Putting a cheap chinese engine on even the best dirt jumper wouldn’t make it a dirt bike or even close to a Segway.
Just don’t do anything too stupid…
 
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