4 stroke reliability and parts availability / build advice

[Toby woodman]

like this. seems slow

 

[Sidewinder Jerry]

Here's the link on how the OP put a 30 series on his bike.

49cc 4-Stroke 30 Series Torque Converter Build

Thought I would share my first build as I have seen some conflicting info about using a 30 series torque converter with a small engine like with this 49cc 4-stroke. I did not document this very well, as this was done over 2 months. The bike has run perfect and has about 300 miles on it. You...

motorbicycling.com

 

[Sidewinder Jerry]

like this. seems slowView attachment 191820

The 144 has around 2~2.5hp at 6800 rpm

 

[Toby woodman]

I might buy an engine kit for a four stroke and then ride it stock. if I decide I need more hill climbing then I will add a cvt. thanks for the help / stopping me from spending a bunch of money on a motor that wouldn't work.

 

[Sidewinder Jerry]

I might buy an engine kit for a four stroke and then ride it stock. if I decide I need more hill climbing then I will add a cvt. thanks for the help / stopping me from spending a bunch of money on a motor that wouldn't work.

I live in the mountains and know what works on steep hills and what don't. I'm also 250 lbs. Those cheap transmissions tend not to last very long.

 

[Toby woodman]

would completely removing the clutch springs and pedalling up to speed and on steep hills help to keep the clutch lasting longer. maybe adding a bigger sprocket at the back as well?

 

[Sidewinder Jerry]

would completely removing the clutch springs and pedalling up to speed and on steep hills help to keep the clutch lasting longer. maybe adding a bigger sprocket at the back as well?

If you remove the clutch springs the engine will overload and cut off while you're stopped. You'd have to lift the rear tire to start the bike. Trying to start the engine on the fly wouldn't be advisable either. Using a larger rear sprocket would be your only real option for hill climbing. Meaning you'd lose a lot of top end speed.

The CVT/JS I suggested would give you hill climbing ability and a reasonable top end speed.

 

[Toby woodman]

I just don't see how I attach a cvt. the shaft for the clutch doesn't extend past the engine case where the cvt would be mounted. would it be possible to install a jackshaft and that way I would have a few different gear ratios for different situations.

 

[Sidewinder Jerry]

I just don't see how I attach a cvt. the shaft for the clutch doesn't extend past the engine case where the cvt would be mounted. would it be possible to install a jackshaft and that way I would have a few different gear ratios for different situations.

The CVT can be attached if you do it like what was done in this thread click onto it.

49cc 4-Stroke 30 Series Torque Converter Build

Thought I would share my first build as I have seen some conflicting info about using a 30 series torque converter with a small engine like with this 49cc 4-stroke. I did not document this very well, as this was done over 2 months. The bike has run perfect and has about 300 miles on it. You...

motorbicycling.com

Your other options are to use the transmission that comes with the kit and then use an IGH HUB as a jackshaft transmission.

 

[Toby woodman]

what about a standard jackshaft for a two stroke bike