X-Pro 150cc // Vader 150 // Lifan 150

[ProDigit]

I just swapped the 35 pilot to a 38 pilot jet.
Idle has become slightly less stable, but still well within expectations.

I upped the main jet from 110 to 115, adjusted 3-4 turns on the AF screw to 1.5 turns, and the bike was stoic all the way through the rev range; however, once the bike was warmed up, it did stutter at WOT, which indicates it was running rich. This due to my muffler, I'm not running a fully open muffler anymore.
The bike also has gained a more consistent acceleration from 1-6k RPM, where as before it would kind of run a little off between 5-6k RPM.
The 6-7K RPM acceleration bump is still there.

I went through the jets, to see if I had a 112 main jet, and found something peculiar,
The 110 jet on my bike was larger than the 110 jet included in the kit.
I have a drill that fits one, but doesn't fit the other.
So what I did, was use the drill on the old 110 jet, to drill it out closer to a 112 jet.
Just put the jet on a rotating drill, and slightly have it file off the sides.
While I can't say for certain the size of the jet, it appears to me to be larger than 110, but smaller than a 115, so somewhere between a 111-114; 112-113 more precisely.

Once mounted the carburetor again, the idle to 5k RPM runs great with the AF screw 2-2.5 turns out, however the top end still seems rich (no burping).
So I turned the AF screw to 1-1 1/4 turn out, and idle to 5k rpm is still good (slightly lower acceleration on the butt dyno), but top end sounds like it's pretty spot on.

Top speed funny enough, hasn't changed. Drafting trucks it slowly creeps to 77-78MPH (72MPH).
If anything, this bike likes to run a bit leaner on the top end; probably due to it's lower compression ratios.

That being said, the 38 pilot is a huge improvement over the 35 pilot, while the 110 to 112 main jet only reduced exhaust noise a bit.

That defines the boundaries of the jetting on the stock engine in my area.



I've been on the fence to get a bigger or smaller rear sprocket, while still being able to maintain top speed if needed.
When running in 4th gear, the bike easily reaches 63 MPH with the 19/30T sprocket setup, and seems it has some extra to go.

So instead of trying to go faster in 5th, I'll try to maintain 65MPH in 4th instead, and leave 5th gear for <50mph downtown runs, or tailgating trucks with a tailwind maybe getting it up to 79MPH.

I'll be ordering a 29T rear sprocket instead of a 31 or 32T in the near future.

But before that, I'd like to see some more data on running 10W40 motorcycle oil vs current 10W30 car engine oil.

So one of my first projects will be an oil change to motorcycle oil.