Vento Zip R3i 90cc stroker project (lots of pics!) :)

[darat]

i will.

[MySpree]

burnt, you also might burn up you gears, you might need to change em, then toast will not be the only burnt thing... there spinning way past what they were ment for... just saying

[burnt_toast]

burnt, you also might burn up you gears, you might need to change em, then toast will not be the only burnt thing... there spinning way past what they were ment for... just saying

thats the thing too, there are no direct fit gears for the zip. i would either need custom machined ones or some import some special ones. plus my friend has a similar setup on his zip with no problems with the stock gearing.

[MySpree]

ok well just makeing sure, so you have a strong nice ride.

[diosoljah]

After spending almost all summer trying to fix my bike, here are the results.

I've gone through countless problems on my quest for a good setup: shredded/worn out belt, melted/worn rollers and sliders, leaned out piston and cylinder, hole in piston, ignition stator went out, air cooling assembly broke off, oil pump malfunctioning, kickstart slipping, and worst of all crank bearings wearing out which made the crank have play.

Well after the bearings going bad, I decided I needed to go deeper and do a complete bottom end rebuild with some other goodies, my goal being a streetable race/stroker setup.. o_o

Here is the full current modlist:
+52mm Ruima Racing cylinder
+42mm Racing ATV crank
with teflon spacers
+koyo 18k rpm bearings
+19mm Arreche carb 100main
+Unifilter airbox
+Polini carbonfiber reeds/cage
+PG short exhaust
+MRP Variator
+5.4g 15x12mm Rollers
+Malossi red Clutch springs
+Malossi yellow Torque driver
+Bando drive belt
+Vented tranny case
+custom spark plug boot
+NGK B9HS
+40:1 Premix with bluemarble
+New fan, shroud and
stator/flywheel assy.
+battery relocated to oiltank
+Koso Deluxe rpm and temp gauge


Pics - click to enlarge:


koso gauge


temp sensor at case


vented tranny case


PG pipe pic


battery relocation


fits in there perfectly


Polini CF reeds and cage


42mm atv race crank and bearings


pipe comparison


PG, stock, Next R


another view


MRP Variator


vari installed


new shroud and fan


need that cooling


arreche carb


nice and shiny


installed


engine comparison


ported 52mm-scored, stock 47mm-scored, new 52mm


The Results
I got everything together the day before college which is 16miles away. Boy was I suprised, got up close to 70MPH (thats about 113kmh) just on a straight after a slight uphill!! and thats with stock gearing, so you can try to imagine the acceleration factor. Biggest difference on the top end was the mrp vari.

Overall results are it can hold 50mph w/ about 1/4 throttle, and 55-60mph w/ half, with ample power at any speed. Jumped on the highway twice and kept up, even passed a few cars. Slight lag from a stop sometimes, but overall response is crisp w/ the cf reeds and power wheelies are easy even with stock clutch. Being a stroker the engine gets too hot for my temp gauge to read so I relocated the sensor to the casing where it has a sweet spot of 158 F at WOT. Mileage isn't too bad at about 50-60mpg mixed riding.

Thanks goes to Speedy for providing a huge amount of tuning advice and the exhaust! To Provo for the long due arrival of the arreche carb and belt. To Dave at strokeitimports for the the engine, crank and other parts. And to thescootercentral for the mrp vari, reedcage, and other parts as well. Lastly all those people out there with fast scoots who where my inspiration.

Great work man...been there with all the trial and error part...just to let you know that I dont think that your an rookie in all this it takes a lot of knowledge in doing stuff that your already doing, jus wondering what was that teflon spacers along with the crank all about? ive heard of plastic inserts to fill voids in the crank itself and it builds a lot of case pressure thus getting some mean * torque. I am planning also on getting a jog (minerelli type) bike soon too so that I can mess around with it.

[MySpree]

whats a mineralli

[se50]

If I'm not mistaken, it's the engines used in Yamaha's, and similar.

[MySpree]

yeam but isnt mineralli like a special type

[diosoljah]

i think originally the minerelli's came from the vespa, et2 piaggio scooters and was and is the engine of choice for the scooter racers of itally and that the motors design was incorporated into yamaha scooters called the JOG if im not mistaken. there are a lot of scooters that also have this design and tons of parts, Im thinking of picking up a MUZ moskito soon which replicates the mid generation jog.

[MySpree]

adn whats so special about it!

[diosoljah]

adn whats so special about it!

from what ive heard, if a dio and a jog go head to head CC's for CC's, the jog is faster, dont get me wrong I still like the dio's...heck all my scoots, four in all are all dios, from strokers to mini strokers, jus want to build and experiment with the jog motors and try something different, like what i said earlier, thats the motor of choice for scooter racers in itally and spain, even in japan the jogs are very popular. correct me if Im wrong but the Dios (Old style) are outdated going back to the 80s from japan honda and the minnerelli's are more modern.

[MySpree]

d*** i almost got a jog
but i didnt know it was good

[burnt_toast]

Great work man...been there with all the trial and error part...just to let you know that I dont think that your an rookie in all this it takes a lot of knowledge in doing stuff that your already doing, jus wondering what was that teflon spacers along with the crank all about? ive heard of plastic inserts to fill voids in the crank itself and it builds a lot of case pressure thus getting some mean * torque. I am planning also on getting a jog (minerelli type) bike soon too so that I can mess around with it.

thanks diosoljah, I appreciate it alot. And you're exactly right about minerelli's. The jog type ones are the origionals that are featured in spains aerox's and aprilias, and can be made into real fast bikes.

My engine on the zip is a minerelli copy, but with built internals as you can see. You're right about the spacers as well, thats what they're made for. They're teflon inserts that fill the space in the crank and build up more pressure. I can definitley feel the difference compared to the stock crank.

I just got another project vento too, but its a bigger bike and a 50cc. This one I'm just gonna mildly mod and aim for economy with decent speed. with just a pipe its already doing 55mph.

heres a pic of it with the stock exhaust: