|
|
Post by repherence2 on Sept 8, 2017 3:21:11 GMT -5
finally decided to register and contribute because this forum has helped me out so much though out my moped journey.
I have a Ningbo GTX 10" wheels.
as it stands now, it has a big block that I bought from a Chinese moped shop for $350. it must have been a ATV motor, it did not have the drum brake assembly. I was told it was a 90 when I bought it. it turned out to be a 50mm bore (83cc?). It now has a Taida 54mm aluminum bore, YMS v8 sectional pipe (90/100cc?), Kelly pulley, OKO 28mm, big manifold/reeds, Stage 6 racing clutch (DIO), Polini Evo clutch bell, NCY yellow contra spring, Malossi gears. big brake rotor kit. Michelin S1 3.00x10 tires.
it can bury the needle. I really don't know how fast it actually goes. I clocked the speedo needle back about 5mph from the stock position. then I rode around with the speedo clear cover off so that I could calibrate/adjust the needle in accordance with those speed signs that have a radar and displays your current speed. calibrated it to 45mph. beyond that, I don't know of the accuracy. the stock speedo face only goes up to 50mph on the speedo arc. so I extrapolated 2 more marks past the 50mph mark. so the 1st tick mark designates 60 and the 2nd tick mark designates 70. im not claiming that it is accurate. all I know is that the needle gets to the 70 mark, which is also the limit of the speedo because of the clear plastic face cover. Full tuck on flat ground. it spins at most 9400rpm at that speed.
along the way, one tuner told me just stay below 350 degrees. another tuner told me to pretty much tune for Wide Open Throttle because if you are racing someone, most likely you will be at full throttle. So, that was the method of my tuning madness. get the pilot at air mix just good enough to get it running. then, tune for wide open throttle, holding it for long amounts and watching the temp. finally you find a Main Jet that suits your carb so that I can hold it at WOT all day and never go past 350 on flat ground. the hottest it gets is 370 up long hills. once I established the Main Jet, I worked down from there with the needle, and then the pilot.
Now this moped SMASHES Honda Elites and SYM dd50's. I remember when those guys would punk me out on the road while I was minding my own business. I have been called out to race many time by these Honda Boys. Here on Oahu, Hawaii, these youngsters are real punks. it feels GREAT to lay a dirsching on them and smash their Egos. It's a Chinese Ningbo GTX with a "Yamaha" big block and it eats up most of the punk Hondas (air cooled, water cooled, it don't matter.) the only two Hondas that passed me was a SpreeDio with a rider that looked about 140 pounds and his buddy on Honda PAL who also looked about 140 pounds. Full tuck, they caught me on the top end after a very long straight. im 240 pounds on a GTX that is as heavy as an Ox.
Good times! Thanks to this Forum and the members that shared their Knowledge.
Smashing punks on Hondas is Priceless. I never paid anyone or any shop to work on this bike. iRead. iLearned. iBuilt. iTuned. Mission Accomplished. thank you 49ccScoot! |
|
|
|
Post by repherence2 on Sept 8, 2017 3:25:25 GMT -5
it also has Malossi gears. aftermarket coil (orange). stock ignition/CDI. stock oil injector pump...no premix for me.
|
|
|
|
Post by aeroxbud on Sept 8, 2017 5:56:18 GMT -5
Welcome to the forum.
Sound like a pretty quick ride. There is something very satisfying about making the needle to go off the clock. I used to get my Aerox past the temperature gauge 😇
|
|
|
|
Post by 90GTVert on Sept 8, 2017 6:13:44 GMT -5
 Glad to hear we've helped you outrun most other scoots!  Most of the bigger Minarellis are just lumped together as 90s, even if they're only 80-something cc. With different bores and strokes stock, it's hard to know exactly what's what sometimes and it's just easier to look at 50 or 90 parts.
|
|
|
|
Post by repherence2 on Sept 8, 2017 10:28:54 GMT -5
Thanks for the welcome Aeroxbud.
90GTVert thanks for all of your write ups and tuning threads. Your videos helped me a lot as well.
This is the site where the Madness began for me and I've done lots of reading and researching on this forum for many years.
190mech, thanks for all of your tuning threads too. I learned a lot from you.
There are others out there too like Bakaracer and Overrev that I have learned a lot from too. Thank you to all that have contributed Genuinely to the craft.
|
|
|
|
Post by repherence2 on Sept 8, 2017 11:00:43 GMT -5
It was originally a small block with a 49cc stock bore. Then I went bore and exhaust Crazy. Chinese 72 economy kit (could not go past 35mph...exhaust port really low). Moto force 72 mid-race. Malossi 72 cast iron. NCY 72 cast iron. I've tried different pipes too. Leo Vince ZX-R. V8 black can, large and small plastic heat shield versions. PG phongeer canister. On the big black, I ran the stock 50mm bore with a NCY 47mm head. It was awesome until I blew a hole in the piston. Too much compression/ squish. It was Pinging too but I didn't know any better back then. Then I had a HOCA 52mm bore running with the stock 50mm head. That was awesome until it died one day. I forgot to install 1 of the piston circlips. Wrist pin drifted over time and gouged a groove into the bore. FAIL!..epic. I went through 2 GTX blocks. I've ripped out threads from the block by torquing the head studs/nuts. Since then, I've torn down one block, drilled out the cylinder stud holes on the block, re tapped to a fit Keensert threaded inserts for 1/4-20 socket head caps crews. I have a Ruima 10-pin crank with Polini bearings and seals. This block is going to be for a brand new Motoforce 72cc mid-race 10-pin. I bought it years ago. The box said 12-pin but it came with a 10 pin piston. That will be mated up with a used Yasuni C21 and an NCY small rotor ignition and Motoforce cooling fan. The 2nd block will be for a new Polini Evo2 water cooled bore that I got for 275. I have a Taida radiator and water pump as well. ...need to get a suitable crank first. Plans and Projects  |
|
|
|
Post by repherence2 on Jan 23, 2018 0:52:23 GMT -5
Since I didn't get my moped legal by 2018 here in Hawaii, I think I'm going to decomission my Ningbo GTX.
|
|
|
|
Post by repherence2 on Jan 23, 2018 1:19:11 GMT -5
Installed Ruima 10 pin crank into 1st spare block, Polini bearings, Polini crank seals, and Motoforce 70 mid race 10 pin bore kit. Removed oil pump. Installed rear facing minarelli intake manifold and Polini CP 24 carb. Modified the rear mounted stock air box to accommodate the 42mm carbi mouth. Installed NCY jog 90 ignition/flywheel (the Ruima crank that I have is a 10 pin but it has big taper and large splines like jog 90). Motoforce cooling fan. It's going to use a Keli variator. I have a Polini Evo 2 shoe clutch (for Dio), Stage racing clutch (for Dio), or a Malossi fly clutch (for Dio) to use on this engine.
As for exhausts, YMS V8 black, YMS V8 bws100 sectional, PG (phongeer) black canister, TKR chamber, or Leo Vince ZX-r available for use. Which one to use?
Also got a Yasuni C21 but I was thinking of saving that for the Polini Evo2 watercooled bore engine build.
I have a few exhausts to choose from.
|
|
|
|
Post by Tanuki on Jan 23, 2018 1:26:41 GMT -5
These new scooter laws are killing all the fun
|
|
|
|
Post by Tanuki on Jan 23, 2018 1:40:59 GMT -5
That was a ton of work to see through!  |
|
|
|
Post by islandscrub on Jan 23, 2018 20:21:13 GMT -5
Since I didn't get my moped legal by 2018 here in Hawaii, I think I'm going to decomission my Ningbo GTX. You could always detune a little. Slap on a stock looking exhaust, air box, heavier weights to keep the rpms down. That's what I'm told you can do, anyway. |
|
|
|
Post by repherence2 on Jan 23, 2018 20:33:32 GMT -5
These new scooter laws are killing all the fun So true, but they had to do something about all the young boys making punk action on Stolen modified mopeds. The new laws actually weeds out the Stolen bikes and it makes it so that moped riders have to "pay-to-play". |
|
|
|
Post by repherence2 on Jan 23, 2018 20:38:04 GMT -5
That was a ton of work to see through! I really don't mind. I learned a lot about tuning on my Ningbo GTX. I bought it from a moped rental company and I'm pretty sure the moped was laid down a few times. I laid it down once. Basically it was a platform to learn a lot about mopeds as far as big bore, CVT tuning, carb tuning, and a whole bunch of Troubleshooting. It was all worth it. |
|
|
|
Post by repherence2 on Jan 23, 2018 20:54:27 GMT -5
Since I didn't get my moped legal by 2018 here in Hawaii, I think I'm going to decomission my Ningbo GTX. You could always detune a little. Slap on a stock looking exhaust, air box, heavier weights to keep the rpms down. That's what I'm told you can do, anyway. Very true Islandscrub. I bought the GTX but never transfered the registration to me for the past 4 years. My plan is to just wait until a 10" wheel GTX, with Safety Check and License Plate, pops up on Craigslist for sale. That way, the moped is legal and legit before I swap out the engine unit. I don't really know if I want to get back into the realm of 47.6mm high revving bores again. My first Motoforce mid race bore mated to the Leo Vince ZX-R was fun. However, I got used to the torque and grunt of the big block engine that is currently in my GTX. 54mm Taida aluminum air cooled bore mated to a YMS v8 sectional pipe for BWS 100. It has Malossi up gears along with the stock secondary gears. The gear ratio seems to be super tall because the engine can bury the needle at around 9000rpm at Wide Open Throttle. It never revs past 9600rpm. |
|
|
|
Post by islandscrub on Jan 23, 2018 21:03:58 GMT -5
If you got the paper with a signature of the last owner, it should be good, just gotta pay the 'took too long' penalty. I think its $15.
I have a frame for the engine, 10" wheel, but the panels were trash so I ditched them, hopefully something comes up in the meantime. Hoping a decent 4-stroke QT-8 body comes across cheap so I can swap panels. If not I've also been on the lookout for the larger frame 12" wheel, the 12" fills in the long block much nicer.
You certainly seem to have jumped right into higher end racing type builds, I'm still on the sport tier myself, seems to be draining my wallet enough!!
|
|
Most of the bigger Minarellis are just lumped together as 90s, even if they're only 80-something cc. With different bores and strokes stock, it's hard to know exactly what's what sometimes and it's just easier to look at 50 or 90 parts.
