Agility City 4t 80cc set up

[rolos]

Hi Everyone! I would like to install a 80cc Airsal cylinder, with stock carb and airbox. I have a Polini variator. What set up should I use? Main jet, roller weights, how long drive boss? Thanks!

[ThehardcoreFTW]

De-restrict everything, drive boss and airbox (washer in intake manifold).

Use 6,5/7,0g roller weights, the latter one gives you more lifetime but slightly less performance (less rpm). I ran about 8K rpm`s @65km/h speedo w/ 6,5g and 8K rpm`s @73km/h speedo w/ 7,0g

Start jetting @+-90 and please don`t go leaner on it for the first time unless you want to risk melting some aluminium, it was the right one for me (living @sea level).

Drive boss? No need to change that with a BBK, that`s just for tuning later on.


Oh yeah, and unless you`ve got a `sports` exhaust, drill some deep holes in your exhaust. The bigger cilinder doesn`t like to choke. Use the search function for that one though.

[rolos]

Thanks for the help! 

[JJJoseph]

What set up should I use?

I mostly agree with the other reply, 6.5g rollers, 80-85 jet, etc.  But one difference: after the BBK install, it wouldn't run properly with the stock airbox, so I'm using a $10 cone filter from Scrappy Dog and it works OK.  Unable to explain why, so I just run with it.  I added a set of gears in the rear (about 15% lower rpms). Another useful mod was a $15 tach from China.  The tach comes with almost no install instructions, but it's possible to figure it out after an hour or so of head-scratching.

[ThehardcoreFTW]

But one difference: after the BBK install, it wouldn't run properly with the stock airbox, so I'm using a $10 cone filter from Scrappy Dog and it works OK.  Unable to explain why, so I just run with it.

That`s right, I modified *cough* my stock airbox for more airflow.

I added a set of gears in the rear (about 15% lower rpms).

Where did you buy that if I may ask? Been searching for that for a good while.

[rolos]

Dear JJJoseph! Can you give a link to the rear gears?

[ThehardcoreFTW]

https://nl.aliexpress.com/item/49-17t-Performance-Final-Drive-Gear-GY6-50cc-139QMB-Chinese-Scooters-Engine-Spare-parts/32387406376.html?spm=2114.48010108.5.9.x03FzZ&&scm=1007.12783.72505.0

^ Did you use these gears? Only ones I could find really.

[mury]

Can this be installed on stock Kymco 50, for higher top speed ?

[ThehardcoreFTW]

Nah, the stock 50cc doesn`t have the torque to pull the longer gears. Try other upgrades and mess with gears once you`ve got more than 70cc`s, otherwise you will only get slower.

[mury]

Nah, the stock 50cc doesn`t have the torque to pull the longer gears. Try other upgrades and mess with gears once you`ve got more than 70cc`s, otherwise you will only get slower.

Thanks 

[JJJoseph]

Dear JJJoseph! Can you give a link to the rear gears?

http://www.partsforscooters.com/169-206_QMB139_Gear_Set