after the stage 2 install... problems.. bogging at 20mph

[yama916]

im in need of your advice...

i have very little experience tuning 2 cycles so i need some directions. i installed the 70cc airsal, malossi variator..
as for the variator it came with 2 metal washer one was thicker than the other, but once i fitted everything i couldnt use it anywhere, so i have 2 washers left over.

19mm arrache carb. the cable was a bit of a pain, the cable i bought isnt quite long enough.. so some modification was necessary.. i left the backing cable totally off so when i turn the throttle other way it revs up... once i get more time ill reinstall it.. stupid mistake just didnt read the how to well enough.. there are 3 nipples on the carb. one is gas easy.. one is tiny and i connected this to the gas tank, the other that goes right on top of the intake tube i connected to oil ... is this right?

exhaust was the easiest no prob..

it is much louder than before with the RS pipe.. but i dont mind the sound too much.. there is slight hesitation off the line.. feels like a bit of mis fire... after a sec or two.. it catches and accelerates incredibly FAST! at about 20mph the power seems to disappear.. like lack of gas... but continues to accelerate at much slower rate.

when i get on and off the gas it doesnt make any difference.. but if i coast for a while there is this huge surge of power.. then again it disappears...

im using the 85 main jet that was on the carb when i got it... there was 65 and 95 i think... im not sure anymore actually..

what could this lack of fuel feeling be? malossi vari only came with one set of weights, do i need to get some lighter ones perhaps? maybe i can use the stock weights?

im 165 pounds.. air temp was in the 20's very very cold, stock air can without the snorkel, besides the 4 mods, 19mm, RS, Malossi Vari, 70cc nothing else...

please help!
yohei

[yama916]

it did pull all the way past 45mph mark.. and was still going.. but it was at night, i was freezing and didnt feel like testing out the max speed yet.. the cylinders/pistons are brand spanking new still..

yy

[pinkymingeo]

Use the thinner (2mm) washer behind the vario. The small nipple is for your oil line. The mid-size is vacuum to the tank, and needs to be clamped with a cable tie or it'll leak. You need a yellow Motorio/red Malossi torque spring and 6-6.5gr weights. 80 main is usually right with stock airbox, but in that cold the 85 might be OK until spring. You can't address other tuning issues until your carb installation and tranny are right.

[pinkymingeo]

Just realized you haven't done anything with your clutch. You must get some heavier clutch springs. About half the time aftermarket torque springs will jam the stock clutch. Maybe you'll get lucky, maybe not. It's best to go ahead and get a Polini 2g. Then you don't need springs. It's adjustable.

[RC51 Daytona]

Start with the main jet the carb came with , or install the jet the cylinder came with. If they gave you one. I have worked alot on 19mm carbs. Unscrew or unbolt the top of the carb , where the throttle cable goes in. You should see a slide, a long tapered needle valve and a spring. Compress the spring so the needle valve is loose. The needle valve controls the amount of gas released to the motor from the main jet. The needle valve has adjustments in the form of three to five concentric rings cut in the needle in descending or ascending order. whichever you like. The needle is held onto the slide with a small, "C" clip in one of these rings. Usually a new carb has the clip set in the middle of the range.

Try this: Take the "c" clip off with a pair of needle nose pliers and place the clip in the lowest slot (the slot closest to the pointy end). This will position the needle valve in a more open position and allow more fuel when the throttle is opened and accelerating. IF IT STILL BOGS WITH THE NEEDLE JET SET AT ITS HIGHEST LEVEL, then consider going to a bigger jet and start over with your adjustments.. Lack of power and the great bogging sound is Lack Of Gas in the cylinder. I hope this helps. :)

[RC51 Daytona]

Also , two strokes with these tiny pistons dont work well in the cold. The colder it is, the more the motor seems to have arthritis.

[wideopen01]

Also , two strokes with these tiny pistons dont work well in the cold. The colder it is, the more the motor seems to have arthritis.

It does bog when it is cold but after like 1 minit of riding the boging does go away...then after it goes away my bike seems to ride ALOT FASTER for the next like 5 min then when it gets to norm temp it is normal and everything goes back to normal....i mean think of it when it is cold...belt,clutch,and all is cold..and you guys know what happens when clutches are hot they tend to slip and slip if you have alot of power... ::handleba

[hungff77]

I think you definitly need to upgrade your clutch and torque spring. The Malossi Vario come with a white torque spring ans it is way too soft for your kind of power. Also, the stock roller (15x12) is smaller than the malossi vario (16x13) and they won't fit. For the clutch, i said a Delta clutch is very good. i think you need that too. You should get it from erich and a set of clutch spring. your bog could be cause by clutch engage too soon and the roller too heavier/or torque spring too soft.

Frankie

[yama916]

okey ive done the few things you guys suggested,
raised the needle so i get more gas
switched the oil line to the tiny nipple, gas vacume line to the top medium sized nipple
installed the 2mm washer behind the vario next to the starter gear.

hesitation off the line has been reduced, still lots of power to 20mph at high rpm, then it bogs down... now im leaning toward premature engagement... probably not gas related. it is directly driven from 20 to 40mph.. very very slow to accelerate. at 40mph the rpm seems to raise faster and accelerate faster.

im using the white spring that came with malossi variator on the clutch side...

im still trying to figure out how everything works in the CVT. front vario is centrifically adjusted, so more weights it pinches more.. and get a taller front gear...

in my case if i used a smaller weights then it would probably be able to pull faster from 20 to 40.. but after that maybe less top end?

the rear clutch side.. the spring is compressing the pully, is the spring strength only for belt not to slip? and the clutch pucks are the ones letting me slip to 20mph but not after that... thats centrifical force as well? if i had tighter clutch then that would solve my problem?

i just bought all these parts and looking for the cheapest way to get it to run right... if that means i have to drop another hundred for delta then that would really suck. if u guys think i can get away with buying a lighter weights... will that solve my problem?

thanks again, its been very helpful!
yohei

[yama916]

Just realized you haven't done anything with your clutch. You must get some heavier clutch springs. About half the time aftermarket torque springs will jam the stock clutch. Maybe you'll get lucky, maybe not. It's best to go ahead and get a Polini 2g. Then you don't need springs. It's adjustable.

i was re reading everything you guys said... so if in fact my white malossi spring is jamming the stock clutch.. i dont really know how it works but then if i reinstalled the stock spring... will it work better than its doing now?

i feel like to get to 35mph its slower than stock... not to 20.. but after 20 its REALLY slow to get up...

yohei

[yama916]

Polini have adjustable control without disassemble. and Delta dont.. but most of you prefer the Delta over Polini? the cost is the same and so i would think Polini is easier to work with???

or i could put in the biggest jet i have 95 i think and see if it does anything else???
yohei

[Lennox]

Polini have adjustable control without disassemble. and Delta dont.. but most of you prefer the Delta over Polini? the cost is the same and so i would think Polini is easier to work with???

or i could put in the biggest jet i have 95 i think and see if it does anything else???
yohei

What size jet have you been running? Put that 95 in ASAP!

[hungff77]

The tranny tuning could be very frustrated sometimes. Becuse it is not just one variable, but it require the balance of the roller/torque/clutch...
Let me try my best to explain:

The clutch is for take off only. But if the clutch engage far below the power band (that is the clutch engage at low rev) you will suffer take off. Sometimes the take of would be so bad that it takes so long to get to 15mph. But once the engine get to the power band (that is reving high enough) the zuma will fly. My experience is the Zuma cannot even go up hill past 10mph because of the clutch engage too soon. A stiffer clutch spring will solve the problem, but if you notice, the stock clutch shoe is so heavy and it will cause the clutch engage soon. The only solution, get an aftermarket clutch.

[hungff77]

The roller and torque spring is closly related to each other. Heavier roller require stronger torque spring. Sometimes people suffer the mid-range due to too heavy roller. It is like the bike shift to the 10th gear already at the mid-range instead of the 5th gear. A strong torque sping or lighter roller will help.

The stock torque spring is too soft for your set up, you will never get it right with the stock torque spring. You need a stronger one for sure. At least a yellow malossi or a red malossi. (I think erich should be able to get you those)

A too heavy roller force the front pulley close too soon (that is shift to high gear too soon.) A too light roller may not have enough force to close the front pulley, that means suffer in top speed.

Frankie

[yama916]

lowered the clip to raise the needle and still the same... (80)

so i just installed the 95 main jet clip at the highest so the least gas...
lots of hesitation off the line, but.. without the air box, it FLYS

so with restricted air im running too rich... i would hate to start cutting out the air box.. but is this a common deal once the stage 2 is installed?
is my assumption right? or are there more to it?

should i buy a aftermarket air box? or just hack it up. obviously louder but at this point i just want it to run good.

so the clutch problem makes sense now that you've explained them to me... basically the stock clutch is weak and if it spins it is engaged.. difference with the stock / 70cc kit.. is this correct to assume that stock 50cc is stronger at lower RPM and 70 is much better at higher RPM? then it makes sence that stock clutch that engages at lower RPM will be a problem once i go to a higher revving motor.. but i would have thought with RS pipe and 70cc i would be stronger than stock even at lower RPM and could pull the same clutch set up.

because off the line the stock clutch may slip but im getting a fast off the line..

just cant get it to run right stilll....

yy

[XPS1210]

with the stuff you said above... you need to open the stock box or to get an after market one... where did you get your parts?

I have an arreche filter... but will get a K&N one when I put the 24mm mikuni on...

[pinkymingeo]

When I was running the 19mm two experts told me to stay with the stock air box. All you get with an open filter is noise. You think you're going faster, but you're not. I took their advice. You had about the right setup with stock box. 80 main/20 pilot/needle rich. I ran that for several thousand miles no problems.

[yama916]

thank you guys for all the help, i finally got it tuned last night!

i ended up with 95 jet, middle clip, five 1/2 inch holes in the air box... now it runs like a champ, it even lifts up the front wheel during acceleration! just a little :)

im amazed with the wot acceleration! it runs like a completely different bike after getting it tuned in! I havent tested anything about 25 ish mph because there's snow on the road now (chicago).

so ill do more testing once it melts away.

thanks again!!!!!

[Lennox]

congrats :yippy: So, did the groundhog see his shadow?

[yama916]

thanks lennox and all the others for your time and help! couldnt have done this without you guys! it will be alot of fun to see how it does on the top end! :) but ill start looking for a delta or polini clutch and springs!

yohei