formula how to improve acceleration from starting point

[x9 rider]

it seems that there are two ways of improving take off speed. no 1 is to opt for lighter roller weight but top speed will be slightly lower & an increased of fuel consumption ( due to high rev ). no 2 is to opt for clutch spring that enggage at lower rpm. for instance let say stock spring enggage at 3000 rpm then look for an after market clutch spring that opens at 2000 rpm. the roller weight however still remains stock. the problem is how to look for clutch spring that opens at lower rpm than stock ? after market spring comes with colour coding. which one to choose from ?
white ? red ? black ? blue or yellow ? 

amalfi 180 has a decent overall performance. i've managed to propel up to max 83 mph. however, with pillion the acceleration from stand still is sluggish. if only i can make it take off a bit faster without sacrificing my precious top end figure. 

[Dave Milnes]

A lighter contra spring on the rear pulley coupled with lighter rollers may work. The rollers would lift the revs on launch and the lighter spring would make the gear ratio rise at a faster rate therefore restoring the RPM/MPH ratio as speed rises. Top speed would be unaffected.
The down side is that a mid speed flat spot could occur, especially if cruising at say 30-40mph and opening the throttle, as the slight 'kick down' rev lift that normally happens wouldn't.

[x9 rider]

dave, in order to avoid the " mid speed flat spot " syndrome, how about if i let the contra spring and clutch spring in stock BUT i mix up the roller weight between light and heavy so that i could have both acceleration & top end ? x9 180 stock roller weight is 10.7g x 6 = 64.2g. what if my roller weight configuration is as follows -

1. 9.5g x 3 + 12g x 3 = 64.5g

or perhaps you have better configuration. by the way , total weight ( me & my wife ) is around 140 kg.

[X9-125-Evo]

Hello

Iv Played about with my bike, my Piaggio X9 125 2004 Evo had the standard 7gr rollers, i went and got a set a pack of 4 different ones.

I tyred Some very light ones, and found the revs was high and by time i reached 70mph (GPS) the Revs where into the Red zone.

So tyred 11gr now acceleration is slow from take off but top end has increased to 78mph GPS, but after removing the front screen and topbox and little fuel half tank of fuel the take off is fast.

If you have a topbox may i suggest you remove it as i find at 70mph or even 60mph the topbox can act like a drag or air brake.

I believe the 180 engine is basically a beefed up X9 125 engine. Topspeed is controled by the gears, a gear up Kit may help, as it did for mine, only added 5mph for me but on top of your 83mph you should get 88mph you mite hit 90mph ( same as a X9250 ) if you get a lighter rider to try her out.

[Dave Milnes]

The two mix roller weight is worth a try it was used a lot on early Honda's.

[X9-125-Evo]

Would you use light rollers for fast take off and Heavy rollers for low revs top end ?

[x9 rider]

Would you use light rollers for fast take off and Heavy rollers for low revs top end ?

most likely, as suggested by dave....for my 1st performance enhancement project i think i'll go ahead with 9.5g + 12g first and see what is the outcome....by the way i dun hv top box. i only hv detachable saddle bag which only use during long distance touring. other than that i just keep it at home. with new roller weight set up, hoping to increase additional 5 mph or more. since my bike is still brand new. bought it early this month. current mileage is 2019 km. still under 6 month warranty. so i dare not to touch on the gearing kit first. maybe, after the warranty period ended, perhaps i'll proceed with my 2nd performance enhancement project which is the gearing kit as reccomended by you guys. however, is it true like what u said a combination of a gearing kit & lighter roller only increase 5 mph on your x9 ? is it applies to all x9 ?

[X9-125-Evo]

well the incress was only a a few MPH and as iam 12 stone, when my buddy rides the X9 he is 9 stone and the bike gets a higher topend.

The gear up kit allows the bike to go faster, if you try to go faster on a standed gear set up, on the X9, you could over rev the engine.

[x9 rider]

to dave & x9-125-evo, tq u for sharing with me your experiences on x9's mods. saves a lot of my money & time on trial & error exercises. what more can i say, such a warm wellcoming feedback from both of you for a new member like me. keep up the good work bros....  

[X9-125-Evo]

Were all good guys , when u catch us on the right day