What order to tune my build?

[tommyd2k]

So I have a 49cc 23 Vitacci Challenger. So far I installed the 50mm BBk, new carb with 85 main jet, new exhaust, new variator with 6.5g rollers, glixal coil and cdi box.

So what I want to know is what would be the best order to tune everything.
I have a kit with main jets from 78 up to 98. A performance clutch with 2000rpm red springs in it and a spare set of 1500rpm yellow springs. Plus I have a set of 6g round roller weights and 7g teardrop shaped ones.

As is, the scooter runs great. I love the power the BBK gave it and the 6.5g variator weights gave me more speed at a lower rpm. The old ones were worn flat and I think that is why to do 45mph I had to have the motor revved to 8k+. I'm gonna pick up an impact gun today and try the clutch at 2000rpm and maybe try the 7g teardrop weights.

Can anyone suggest the best order to test out different configurations to find what works best. Id really appreciate any advice.

Thanks a lot.
TD

[FrankenMech]

Check with the build section or the tech section of the forum.

[pete130]

May 23, 2024 10:04:26 GMT -5 tommyd2k said:

So I have a 49cc 23 Vitacci Challenger. So far I installed the 50mm BBk, new carb with 85 main jet, new exhaust, new variator with 6.5g rollers, glixal coil and cdi box.

So what I want to know is what would be the best order to tune everything.
I have a kit with main jets from 78 up to 98. A performance clutch with 2000rpm red springs in it and a spare set of 1500rpm yellow springs. Plus I have a set of 6g round roller weights and 7g teardrop shaped ones.

As is, the scooter runs great. I love the power the BBK gave it and the 6.5g variator weights gave me more speed at a lower rpm. The old ones were worn flat and I think that is why to do 45mph I had to have the motor revved to 8k+. I'm gonna pick up an impact gun today and try the clutch at 2000rpm and maybe try the 7g teardrop weights.

Can anyone suggest the best order to test out different configurations to find what works best. Id really appreciate any advice.

Thanks a lot.
TD

I only change 1 thing at a time with testing, so you know what is changing bike, changing a few diffrent setting at a time can get confusing as you may not know what's doing what

[tommyd2k]

I ended up using a 1500rpm set as the 2000 didn't feel right. 7g sliders for now and 88 main jet.

I just discovered that I installed my intake spacer wrong a few weeks ago. Now that it's oriented correctly I gotta re-tune my carb. The gas mileage was terrible and it would run too rich no matter what jet I tried.

I bought a 21mm PWK carb and intake (I don't plan on installing it right away) and I was test fitting everything yesterday and discovered the spacer issue.

Now I wanna get this carb setup right and see what it'll do. Once that's dialed in I am gonna try the PWK and see how I like it.

Eventually I plan to swap out the drive gears to raise my top speed. And when riding season ends I wanna replace the stock crank with a 44mm.

Parts are so cheap and it's simple to work on. So I'll basically try anything to make it quicker.

The PWK carb I bought is a "Maikuni" (not Mukuni lol). Has anyone used one of these on an 82cc gy6? The intake I got has the vacuum nipple in a spot where it hits the timing chain tensioner cover. So I had to pull it off and block the hole. It has a lot of plumbing I gotta figure out. I'll prob start a new thread when I start playing with that setup.

For now my top speed is about 44mph. I need a good app to test acceleration if anybody can recommend one.

Again thanks in advance for any advice.