36MPH on a 4 Stroke

[Will'smotobikes19]

The clutch doesn't last long on the 4 stroke.

The bushing clutch on 49cc kits are junk. I might have a try at a homemade manual clutch using a belt and tensioner. Most people run 49cc or 79cc. Just don't generalize clutch problems when you hear 4 stroke. It's all Chinese that's why nothing lasts.

 

[Sidewinder Jerry]

The bushing clutch on 49cc kits are junk. I might have a try at a homemade manual clutch using a belt and tensioner. Most people run 49cc or 79cc. Just don't generalize clutch problems when you hear 4 stroke. It's all Chinese that's why nothing lasts.

Mine's a Japanese one. Though with small engines the right gear ratio for a given terrain and/or load is vital to longevity in a centrifugal clutch.

 

[Will'smotobikes19]

I had an eho 35 it was too underpowered for these hills. With vigorous pedaling it would make it up the hill but if not pedalling you could jog next to it. 49cc is an improvement,

Most kids/people are going to run 2 strokes regardless seeing the wide pedals as some sort of issue. Also ranting about 40mph top speed. I'd rather go 10,000 miles with a slightly lower speed than 3,000 miles and a rebuild. 49cc 4 stroke kit motors are a Honda in a nutshell much like the 49cc 2 strokes being copied from a japanese motor. My engine has no problems so far just everything around the motor breaking like I said the 49cc 4 strokes are usually good engines except for bad rings and rods break every once and a while going full rpm down a hill from some of the stories I heard. Sometimes improper break in will cause them to go bad.

 

[Sidewinder Jerry]

I had an eho 35 it was too underpowered for these hills. With vigorous pedaling it would make it up the hill but if not pedalling you could jog next to it. 49cc is an improvement,

View attachment 104686

Most kids/people are going to run 2 strokes regardless seeing the wide pedals as some sort of issue. Also ranting about 40mph top speed. I'd rather go 10,000 miles with a slightly lower speed than 3,000 miles and a rebuild. 49cc 4 stroke kit motors are a Honda in a nutshell much like the 49cc 2 strokes being copied from a japanese motor. My engine has no problems so far just everything around the motor breaking like I said the 49cc 4 strokes are usually good engines except for bad rings and rods break every once and a while going full rpm down a hill from some of the stories I heard. Sometimes improper break in will cause them to go bad.

Most of the issues you describe can be solved with 3 things.

Tachometer/hour counter
Wide reduction range shift kit
Scheduled routine maintenance

My shift kit reduction range is 66.79:1 to 16.25:1. I use a triple chainring shift kit is how I get such a wide range. This way I can always use my tachometer to be in the right gear ratio for a given terrain.

My engine (RS 35) Max hp is at 7000 rpm, the max torque is at 5000 rpm. At full throttle if I can't get at least 5000 rpm then I'm in too high of a gear and need to down shift. At full throttle if I'm going over 7000 rpm then I'm in too low of a gear and need to up shift. Engine strain can be just as damaging as over revving.

The hour counter will let you when oil changes are needed and air filter cleanings. I also like to replace the fuel filter after a 100 hours of use. My engine has held up for 11 years. All I've ever replaced is fuel filters and spark plugs. Oh and I live in a mountainous region of the country.

 

[Deleted Member 4613]

I believe I figured out the higher clocked speed here with this geared gearbox. According
to bike berry, it is a 3:1 gearbox, whereas the belt drives are 4:1. By my calculation,
the top speed with a 44 tooth rear sprocket, and a 10 tooth drive sprocket would
be 39 mph, theoretical. They are getting 37mph, and sacraficing torque. A 4:1 belt
drive is better, offering more torque and lower top end speed. Their gearbox at
3:1 would offer no hill climbing capability at all.

 

[darwin]

Honda 50cc motor's are God's gift to man for inventing bicycles, capiche?

 

[Sidewinder Jerry]

Honda 50cc motor's are God's gift to man for inventing bicycles, capiche?

Got one. Hope to have it on my bike one day.

 

[darwin]

I'd like to hear from someone who's bought the gx50 clone and how it is in power/quality. Not the GXH50.

 

[JerryAssburger]

I believe I figured out the higher clocked speed here with this geared gearbox. According
to bike berry, it is a 3:1 gearbox, whereas the belt drives are 4:1. By my calculation,
the top speed with a 44 tooth rear sprocket, and a 10 tooth drive sprocket would
be 39 mph, theoretical. They are getting 37mph, and sacraficing torque. A 4:1 belt
drive is better, offering more torque and lower top end speed. Their gearbox at
3:1 would offer no hill climbing capability at all.

You're right. It's the 3>1 cheapie chain box. For a 13.2>1 ratio, I'm pretty impressed he got it moving along as well as he did. As a matter of fact, this particular video "sold" me on the purchase of a 4-stroke/belt kit. Glad I did it.
The engine is flawless. It seems to be running a bit lean on the main jet, and I'm still in the process of breaking it in.

 

[Deleted Member 4613]

I'm hesitant about buying a chinese 4-stroke kit with a belt drive due
to too many people complaining about clutch problems.