I hear you about the holes. I have read pros and cons, and I take them very seriously, but at my altitude, which is actually closer to 6000 feet where I live, there just wasn't enough air. The engine simply would not rev.
Now, with regard to these 70 cc kits, what would you recommend for my scooter, and how hard are these things to install? Do you have to drop the engine? Frankly there's a cost/benefit thing with me and this whole upgrade scenario, in that for the money I have spent and might spend I could probably buy a used 125 or 150 used, but OTOH it is kind of interesting. I might end up buying a larger 4-stroke at some point, but I would still keep this one to play with.
Percentage-wise, I went from hitting 40 downhill and usually topping out at 37 or so on the speedo, so now I am at 43-45 on the flat and who knows how fast downhill, with much faster takeoff and better speed up hills, so I think I got a 15-20% increase for $350. Whether that's worth it I have to dwell on, but I also think that someone who really knows these things could get another few mph out of the machine, and I may see if there's someone in my area who could help. You've been enormously helpful, but there's only so much you can communicate via forums.
For right now I will try to tune the carb as best I can and see how it goes.
One more thing: I do need new tires...any recs? I would like better wet traction, if possible.
The 70cc kit is fairly easy to install, you have to remove the pipe &carb
then 4 head nuts and the head & cylinder will come off.
then remove a 'c' clip and push out the wrist pin
remove piston and cage bearing in the connecting rod
and rebuild. if you know your scooter its about a 3-4 hr job.
the motor stays in the frame.
you will never find a 4t that will be is as quick off the line and have the power
a 2t has. the only advantage is that you have a cheaper/less expensive higher
top speed ,,, you can get to the same top speed but you will have to
put on a cylinder kit and replace the final drive gears. but you will smoke
most 4t's
FYI; if you were to compare the 2, lets say you have a 100cc 2t
, you will need a 170cc 4t to equal the same power to weight ratio
you could perhaps eek out a 1 or 2mph but you are about right at 7mph
increase for your mod..
also the 4t motor is a lot more involved , trickier . and you need
lots more specialized tools. then your mods only have half the mph gain
for about the same money and a lot more work if you were to replace
say the cylinder..
oilyhans