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poolpool1
Guest
add an octane booster,, ~ whole bottle yep..NOS is great..
How do i get more torque out of the engine?
- Thread starter ThunderBubble
- Start date
P
poolpool1
Guest
needle bearings just fry baby..try a bigger motor. happy scootting!!
Jtsmotos
New Member
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Yes there is, you can buy a subtropical clutch kit for the bike motors. Amazon carries the necessary items you need. Check it out
Welcome to the forums...unfortunately your answering someone who hasn't been seen in the forums in 4 years now and the last post before yours has a posting date of April 22, 2017 as you will be able to see...Your not the first new member to do this and im sure you wont be the last either...lol...DAMIEN
Frogslayer
Well-Known Member
You did do the world some good though as reading subtropical clutch out loud made me laugh.
You and me both...Does that mean that centrifugal clutchs are subtropical in nature ???...lol...DAMIEN
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Karl Snarl
Well-Known Member
two words, jackshaft kit. boom, speed and torque in one sexy package.
Chop-chop
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I'd just posted this in one of the other threads....so I just cut n pasted it here for u guys...
I run a 32t sproket at the rear of my Schwinn chopper for top end so if anybody needs extra torque, it's me and here is the method to my madness....and to think I'll be going down to a 27tooth soon !
Installing a thicker base gasket down between the jug and the crankcase will rise the port position to alter the exhaust port timing to promote more bottom-end torque, some people will go as far as using a billet spacer along with liquid gasket to seal. Either way the downside by doing this, is the cylinder volume will increase and reduce compression, so to compensate for the reduction in compression, a thinner head gasket OR milling the mating surface of the head will be required in order to restore OR even better, increase compression for even more ooomph... just BECAREFUL to check your squish band regularly to make sure you haven't overdone it and caused the piston to smack the head ! Turn the whole shooting match over by hand to make sure the piston isn't hitting before actually cranking the engine over....
You can get rolls of gasket paper in various thickness at the local autostore for making your own base gasket. As for the head gasket - go to your local hobby store and find copper sheets in different thickness, use the dremel to make up your own head gasket in copper, just make sure your heat it up on the stove to soften it before fitting to help it seal.
Whilst the engine is apart, tidy up the inlet and exhaust ports by removing all casting dags, even widening the ports to aid flow, just becareful to match the ports to the manifolds to eliminate turbulence. Do the same for the transfer ports between the jug and the crankcase by using the base gasket as the guide (Refer to photo - sitting the jug on top of the crankcase without the piston to port match the transfer ports). Dremel has special tungsten carbide cutting tips that are perfect for doing ports - they aren't cheap at $20 - $30+ each but they last forever when used with aluminium these jugs and cases are made of. ( Dremel part numbers 9901, 9903, 9904, 9906, 9931 are the ones I stock up on.)
Experiment with different thickness gaskets to achieve the desired performance and power output. I do everything listed here before installing and running in each new engine. You'd be amazed at the difference compared to just wacking on an untouched unit and just running it.
One other thing I'm looking into is to play with ignition timing by changing the location of the magneto magnet relative to the piston position/TDC or doing it electronically using something like the 'Powerspark' ignition system originally designed for RC 2 stroke applications.. you can achieve additional torque by advancing ignition timing..
I run a 32t sproket at the rear of my Schwinn chopper for top end so if anybody needs extra torque, it's me and here is the method to my madness....and to think I'll be going down to a 27tooth soon !
Installing a thicker base gasket down between the jug and the crankcase will rise the port position to alter the exhaust port timing to promote more bottom-end torque, some people will go as far as using a billet spacer along with liquid gasket to seal. Either way the downside by doing this, is the cylinder volume will increase and reduce compression, so to compensate for the reduction in compression, a thinner head gasket OR milling the mating surface of the head will be required in order to restore OR even better, increase compression for even more ooomph... just BECAREFUL to check your squish band regularly to make sure you haven't overdone it and caused the piston to smack the head ! Turn the whole shooting match over by hand to make sure the piston isn't hitting before actually cranking the engine over....
You can get rolls of gasket paper in various thickness at the local autostore for making your own base gasket. As for the head gasket - go to your local hobby store and find copper sheets in different thickness, use the dremel to make up your own head gasket in copper, just make sure your heat it up on the stove to soften it before fitting to help it seal.
Whilst the engine is apart, tidy up the inlet and exhaust ports by removing all casting dags, even widening the ports to aid flow, just becareful to match the ports to the manifolds to eliminate turbulence. Do the same for the transfer ports between the jug and the crankcase by using the base gasket as the guide (Refer to photo - sitting the jug on top of the crankcase without the piston to port match the transfer ports). Dremel has special tungsten carbide cutting tips that are perfect for doing ports - they aren't cheap at $20 - $30+ each but they last forever when used with aluminium these jugs and cases are made of. ( Dremel part numbers 9901, 9903, 9904, 9906, 9931 are the ones I stock up on.)
Experiment with different thickness gaskets to achieve the desired performance and power output. I do everything listed here before installing and running in each new engine. You'd be amazed at the difference compared to just wacking on an untouched unit and just running it.
One other thing I'm looking into is to play with ignition timing by changing the location of the magneto magnet relative to the piston position/TDC or doing it electronically using something like the 'Powerspark' ignition system originally designed for RC 2 stroke applications.. you can achieve additional torque by advancing ignition timing..
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Street Ryderz
Well-Known Member
This info is incorrect and again it's all been posted here correctly through out many threads! Chop Chop you have a 20" wheel on a Schwinn stingray (chopper) and the normal size gear for those is a 30 tooth other wise the engine screams at 9k rpm just to give 29 mph with the stock gear, with a 30 tooth it's only 6k rpm for the same speed and it doesn't really load up the engine requiring more torque.
Raising the jug/cylinder does not aid in gaining torque, the slight bump in port timing sacrifices torque for better flow at higher rpm, though less than 1mm really doesn't do anything.
The timing being advanced also sacrifices torque NOT help it, and worse it will cost upper rpm due to detonation being more likely, the stock cdi's base timing is 20 degrees btdc and as rpm climb so does the advance well above 30 degrees btdc which is not wanted in a 2 stroke above 8k rpm as again detonation is more likely, where a properly timed 2 stroke will have 18 degrees or less when anywhere above 8k rpm. Performance 2 strokes will only have 10-8 degrees advance at 8k rpm and above.
The only ways of gaining torque are to bump up the compression (a fair bit) and to use port timings and volumes that aid the flow in that range, which means you sacrifice having a higher top rpm so it's best to find the happy medium that works best for the application.
I run with a 27" wheel and use an 11 tooth drive gear on the engine with a 30 tooth on the wheel which is 11.2 overall ratio rather than 18.0 with stock gearing and that requires alot more torque to accelerate and maintain rpm under load! This setup accelerates from 0 to 50 mph in 7.5 seconds and tops out well over 60 without having to spin the engine up over 10k rpm, at 10.6k rpm the speed is 73 mph though that last bit of rpm takes awhile to get to as drag coefficient adds load and torque falls off toward peak rpm and it all relies on the pipe and tuning at that point!
Sidewinder Jerry
Well-Known Member
I have a 33cc 4 stroke engine. Even though my lowest reduction ratio on the shift kit is 66.79:1; I still pedal on take offs in spite of being in 1(1).
