[ProDigit]

200 mile review.


Fuel Mileage:
I've taken the bike to and back from work the whole week, and I've just also done a ~36 mile fuel mileage ride. It was more like 38 miles, but 36 miles recorded with stride from fuel station to the same station again, as well as measured by the bike's trip odo.
Like most of my Chinese bikes, the ODO was spot on (within perhaps 0.1-0.3 miles difference from stride, or less than 1% off); despite the speedo to be off by about 7%.
I wanted to do a 100 mile ride, to get a more precise measure of odo and fuel consumption, however my butt and back didn't agree with my head there.
I had to return from my joy-ride earlier than expected.

I did measure by topping off the fuel to about 1/3rd of the fuel tank neck on the top. That is after shaking the bike a bit, because the fuel sinks about an entire fuel cap neck just by doing that.
Upon my return, I fueled up to halfway the neck, filling it up generously, a bit more than was before, just to be on the conservative side with the fuel.

My 36 mile trip mostly existed out of urban roads doing 30-45MPH (<5k RPM), some stop lights, all at ~4-8ft of elevation, with an occasional 50MPH (6k RPM).

The fuel used was 0.43 Gal, which amounts to 83.7 MPG (that is with the 18T sprocket, and driven mostly calm).
Taken into consideration that the actual mileage recorded was 36.7 (I live 0.7 miles from the station), and I fueled up more upon return than leaving, the actual MPG value will be closer to 85MPG.

In my day to day use however, this will drop below 80, as much of my way to work will be at 50-60MPH, not 30-45.

Turn radius
During the trip I've noticed the bike's turn radius was so bad, it took 2 entire smaller street lanes to make a U-turn.

RPM findings
I also noticed that the bike bogs down a bit when starting from a stop, due to the higher gear ratio. Nothing major, just a small RPM range where the engine revs down, and the bike moves forward, where I need to feather the clutch a bit more. Once the bike starts moving past ~1.5-1.7k RPM, it all works fine. Could be due to the restrictive exhaust.
The bike doesn't like to be below 2k RPM in 1st gear, and below 3k RPM in 3rd, or 4th gear. From 3k RPM onwards it accelerates quite well.


A/F ratio impressions
The bike uses a bit of a rich pilot, probably so they could go lean on the main jet, and have the fuel cool down the bike during idle, as pitbikes and stunt bikes usually have few bursts of acceleration, combined with idle time.

Timing impression
During my ride, I was thinking how the bike is set up for stunt riding, pitbike riding, offroad riding. The advance on that enigne is quite retarded between 3-5k RPM, which is why it runs so well in that range, and why it has so low MPG numbers (any 150cc bike should be able to get 100-120MPG), even with better gears. It also has quite a low compression ratio, which means these engines could run quite hot without issue.
Which means, if I push the gears from a 15T/34T to a 19T/30T configuration, the engine should be able to push those gears quite easily at between 3-6k RPM.
The reason I want to do that, is because I want to turn it from a hooligan stunt bike, to an economical cruiser bike to take to and back from work everyday.

Exhaust
Once I remove the restrictive exhaust, backpressure will drop. This will cause lower torque in the ~3-6k RPM range, but should significantly improve the engine's idle to 3k RPM idling capabilities. Even should be possible to run a much lower idle (closer to 1200RPM).

But with the stock exhaust, I think I'll increase the idle from 1500-1750RPM to 1750-2k RPM. It should help with starting from a stop with those taller gears.

Once the exhaust is replaced by a non-restrictive one, the pilot jet will probably be at the perfect mixture, however, the main jet will be too small.
Due to regulations, they have locked their carbs, so you can't open them to swap or modify the jets :/....
I'd still want to try though...

Seat
The bike's seat is comfortable enough as a daily driver doing 10-15 mile (20 min) trips, however the rear passenger seat hump is pressing on my tailbone, and killing my butt and back for longer trips.
I can't really sit on the passenger seat, because I have a saddleback (storage bag) on there.
This was another one of my pet peeves, that the bike has no storage space at all; despite the company having so much space between the engine and the fairings; they neglected to make this bike also practical.
I'm looking for some seat covers, perhaps get some foam or gel pads, and staple a leatherette seat cover over them to the seat. Shouldn't be too hard to modify the seat, all I need is some good material that can withstand sun and rain.

Chain/chain sliders
I had to adjust my chain after 100 miles. I knew this was going to happen. The chain sliders really need to be replaced. You can adjust the chain tension, with the rear wheel bolt still properly torqued.
Still they are practical.
As soon as the smaller rear sprocket arrives, I'll also install the 19T, with the new sprocket cover (hopefully on Tuesday) that I'll have to grind down to fit the sprocket and chain in there.
Then I can double nut the chain adjuster bolts, because a single bolt is just going to rattle off.
I did use paint, to keep em in place, as locktite is usually a more permanent solution, even the blue one.

Comparison
This bike cost me $1400 shipping included, which was only a bit more than my $875 Roketa MC 05 127 bike with $250-350 shipping (I forgot), but it also is significantly more of a bike than the roketa.
The roketa was good, but it suffered from a bad transmission. The step through gearing really suck, are unsafe, and I don't know why they wanted to push them on beginner riders?
Aside from that, the gearbox often slipped at higher speeds. Granted, I was using semi-synthetic oil in the bike. Still, they should make the bikes compatible with regular motor (car engine) oil.