agility 50 now 70cc low speed

[reg]

Hi, i just drilled three 4mm holes eaqually spaced in the rear of the silencer. The engine seems to rev easier, i guess my drilled holes are compensating for a slightly choked up silencer. its not any noisier.
removing the restriction in the intake manifold didnt make any difference, maybe due to my setup. I changed to a free flow fliter but the induction roar was very loud, i changed back to standrard intake (derestricted) and drilled ten 8mm holes along the bottom of the filter box. Speed now back up to 46mph, ( 70kph ). When i duck down behind the handlebars, boy racer style, there is no speed increase at all so i suspect i could still ' raise the gearing' a little more. Only problem is that i cannot skim any more off the variator boss as after checking the belt is rising up all the way to the edge.

That elusive 4mph i need to reach the magic 50mph is there somewhere i have just got to find it !!!

[phatboy]

cool I will drill some holes later, also going to grind the boss a little

the intake tube mod does seem to make a difference on mine, it seems to be running way lean now, I upjetted and am going to try it out later and also need to adjust the idle mixture screw, idling got rough after the mod

as for more power i don't know yet, though the scoot topped out at 42 before the mod actually 1 mph less than before my bbk, definitely lots of potential to get out of it still.

50 mph that would be nice, but yeah I agree it seems to be all gearing, i wonder would a race cdi help? So it can rev higher?

[phatboy]

i suspect i could still ' raise the gearing' a little more. Only problem is that i cannot skim any more off the variator boss as after checking the belt is rising up all the way to the edge.

That elusive 4mph i need to reach the magic 50mph is there somewhere i have just got to find it !!!

Was thinking why cant you literally raise the gearing? not the variator but the final drive gears.

i found this kit:
http://www.scooterdynasty.com/gearsnarakufinaldrivefor50cc4-stroke139qmbscooters.aspx

couldnt find too many kits like this, changing gears doesnt seem to be a common mod, i wonder why, seems the cvt could compensate for the taller gears at low speeds

[reg]

Hi, I have seen gear-up kits advertised for the a50 but they always seem out of stock everywhere i look. i am convinced a gear up kit is the way to go. Its illogical to fit larger engine components without raising the gearing to apply that extra power. I know from my two stroke piaggios that a big bore kit is usually matched with a gear up kit. My engine is around 35% up on power so a gearing raise of 17% wouldn't seem too much for the engine to pull.
I might find out what gears are used in the a125 and see if they are compatible, although i suspect they may be too high.
I did my usual 20 mile each way cross country trip yesterday, first time since shortening the variator boss. The journey was transformed, its amazing what a difference those few extra miles an hour make. as the scoot was faster i was ' busier' instead of seeming like i was sitting there stationary with the road rolling underneath me. The 1000rpm clutch spring really helps the scoot to come back up out of bends, like dropping down a gear on a manual bike.
Very pleased with a50, very pleased with this site and its helpful team of members.

cheers

reg

[reg]

Hi, found this site helpful. I know its mostly about two strokes but the variator/gearing stuff is useful

http://www.pedparts.co.uk/blog/do-i-need-a-gearup-kit-with-a-malossi-or-polini-sport-70cc-kit

[phatboy]

cool thanks for the read.

i am wondering now if that gear set i posted would actually help, i read somewhere else that kymco already uses a taller gear set than most scooters but cant confirm.

the naraku set promises 10% if you have a 51-15 or 52-16 set which isnt much.

I counted the teeth on the  gear in the kymco service manual and got 41, couldn't count the pinion gear due to the angle.

There is a Hoca set that offers 41, 42 and 46 on the big gear, 16, 17 and 18 on the little gear. So maybe the gears are already good?

EDIT: OK, never mond the 41 was from the illustration, the picture shows 52-16 gear set stock, this means the hoca gears could offer a big improvement

[reg]

Hi, i found the naraku gear up set here: http://www.pedparts.co.uk/product/1981/secondary-gear-up-kit--gy6-4-stroke-naraku-racing

Going to order, its only a 10% increase but that will get me to the magic 50mph ! I dont want to sacrifice reliability so i figure its a modest increase in workload for my engine ( 68cc). Same reason i havent fitted an a9 camshaft or bigger carb. Planning a long trip later this summer so need it to last.