Tweaking the top end (more "sustain")

[premnas]

Hey all!

I've got just over 400 miles on my scoot, and I'm pleased as punch with the 22 bucks worth of transmission mods I installed. The scooter's top speed is fine.  According to the speedo, it'll pull 51 down a hill, 45-47 on a long, flat stretch, and 40 up a slight grade. I don't know how accurate the speedo is, but no matter- the scoot keeps up with the city traffic I drive in, and I'm not looking to gain any more top speed.

Acceleration 0-30 is great, but where I'd like a little more umph is from 35 mph on up.  I'm not looking for anything spectacular, but if I could tweak the top end to have a little more grunt (not speed), I would truly be happy with the scoot's performance.  Feels like I just need a little more "sustain" at higher speeds.

I've cut the CDI, replaced the boss drive, and I'm using 5 gram rollers with stock fly springs and stock main torque drive spring.  I really feel like the transmission is dialed in for the riding I do, and that if I could tweak the engine to get just a little more out of it I would have a great combination going on.  I'm thinking a K&N air filter, and larger main jet (85) would help...

Any thoughts or suggestions?  I wouldn't be opposed to different roller weights or a stiffer torque spring, but as I said, it feels to me like the transmission is pretty well dialed in.

Thanks!

[sidthesloth]

24mm carby perhaps? 

[sticlistul]

85 its a to small jet for a K&N I say it will take from 90 or bigger you wont bielive but a pall from forum (slinger) used to have 105 with his old carb and K&N  .

For better acceleration from 35 up I think you need more power ...but I think thats all power which can be delivered from a 50 cc engine without major mods , if you really want more power I recomend you a bigger kit ...but remember that kymco engine it's made to last very much ,slinger has 45000 km with his stock engine ...

[wordslinger]

..both of these guys are right...larger carb will help....some...

..free-flow filter and maybe a 95 jet will help...some...

..performance exhaust and another jet increase will help...some...

..however, the 49.5cc 4-stroke engine is forever going to be beat down by hills and headwinds...

[sticlistul]

good to mention headwinds , I loose almost 10 km\h with headwinds , but not in city just outside . Anyway I know what premnas wants from 50 to 75-80 km\h more acceleration , in city you really need that ...but I don't know if there is something you can do just with 50 cc I prefer to let mine like it is and enjoy

[premnas]

Thanks for the replies!

I'm not really unhappy with my scoot's performance, especially in light of the fact that I had to spend only about 30 bucks to get it where it is.  I'm still open to air cleaner/main jet mods as these are inexpensive too, but I really don't want to commit to big bore kits, larger carbs, or performance exhausts simply because of the expense.

I was already thinking that there was a limited amount of performance to be had from a 49cc engine...