Tuning for speed :)

nickaloadien

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Been enjoying riding my 76cc china motor but I wanna try and get it faster. Just finished up another top speed test I maxed out at 48km/h (30mph). What are some thing I can do to go higher? I have a mz65 clone pipe on. Is the squish important for speed? I’ll need to buy solder and a digital calliper if so. I ported it a little bit without checking timing and all that which I don’t know how to do.

I have a #85 jet in there and the clip on the middle position out of the 5. I noticed I gained 3km/h when switching from a #80 to #85.

is bogging down when you’re too lean and four stroking is too rich? It’s definitely doing one of those at max speed.

Also will retarding or advancing the timing do anything? Sorry a lot of questions lol love this community
 

Chainlube

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Been enjoying riding my 76cc china motor but I wanna try and get it faster. Just finished up another top speed test I maxed out at 48km/h (30mph). What are some thing I can do to go higher? I have a mz65 clone pipe on. Is the squish important for speed? I’ll need to buy solder and a digital calliper if so. I ported it a little bit without checking timing and all that which I don’t know how to do.

I have a #85 jet in there and the clip on the middle position out of the 5. I noticed I gained 3km/h when switching from a #80 to #85.

is bogging down when you’re too lean and four stroking is too rich? It’s definitely doing one of those at max speed.

Also will retarding or advancing the timing do anything? Sorry a lot of questions lol love this community
76cc, never heard of it, is that a hybrid?
The squish is important, put the solder through plug hole and against the cylinder wall, turn engine over and then measure how thick the dent is. If no dent, then you have some work to do. Report back on that.

A real MZ pipe is bigger and better than the clone, and a jog pipe is better still but has to be fitted. Each pipe will hit a certain RPM range. After that they will sputter and bog.
 

Sidewinder Jerry

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So before you drop a lot of time and money into speed; first make sure you have enough Stopping power to handle the speed. Also make sure your frame is reinforced and the wheels are upgraded to handle the increased speed
 

Redneckcruisersoftexas

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You have to understand that a motorized bike can be built to go fast (for a bicycle), but it’s kind of like a Miata you can go as fast as you want without going over the speed limit 😂
 

Nickt919

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So before you drop a lot of time and money into speed; first make sure you have enough Stopping power to handle the speed. Also make sure your frame is reinforced and the wheels are upgraded to handle the increased speed
I went in reverse order building my bike. Engine mods first then the brakes/frame afterwards.
This is a natural tendency but it’s also NOT advisable.
Once I got to 30+ mph I realized I needed much better brakes.

If you’re in this hobby for the long haul it’s best to address the safety first so you can be around and standing to finish the high performance engine aspects.
 
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