Polini Tuning, Timing and I'm fucking stuck. Help!!!!

Here’s the set-up:

Puch E-50 Kick start (Pain in the ass to set timing)

Polini 64cc kit (case, intake and exhaust matched)

Treats High-comp head

Bing 15mm

Techno Estoril Pipe

Treats CDI

B7hs spark plug (also tried an iridium B8 but no difference)

The problem:

It runs very well at idle but as soon as I pull the throttle it begins to stutter and sputter.

I have tested for air leaks and found none, tried various jet sizes from 74 to 90 and messed with the timing.

I thought I had the timing down but in the end I have come to the conclusion that I’m confused. Here’s what I’ve done:

First off I removed the woodruff key so that instead of rotating the stator plate I’ve been moving the flywheel. Which is awesome because every time you move the flywheel to adjust the timing you have to find TDC again since the flywheel has been rotated. So much fun!!!

Found top dead center (TDC).

Look down on the flywheel I set the timing so that it fires 20degrees to the LEFT of TDC which is 1.6mm Before TDC. I have read that this is a good place to start without being terribly aggressive.

The odd thing is that as the rpm’s increase the CDI fires CLOSER to TDC. At like 10degrees. Shouldn’t it be the other way. The only two possible reasons I can think why this is happening are:

1. I’m completely confused and have set the timing up completely wrong

2. Treats sent me a ZA50 cdi

I need help with this. I’ve stared at the flywheel for long periods of time trying to envision the inner workings of ignition points, retarding/advancing and what happens when you rotate the flywheel on the crank as opposed to rotating the stator. In the end I thought I had it all figured it out but the moped runs like a steaming pile of dog shit on a hot & humid summer day. So I’m reaching out to all the tuning gurus on here to help me with my shortcomings.

Thank you!!!!

I've attached a picture of what's going on with the timing and how I have it currently set up.

Ignition.jpg

Re: Polini Tuning, Timing and I'm fucking stuck. Help!!!!

Not techno estoril. It's a DMP Estoril pipe.

Re: Polini Tuning, Timing and I'm fucking stuck. Help!!!!

Probably Fred /

Where did you read 20 degrees for a polini kit?

16 degrees is safe .

My treats cdi did not have a curve ( crapped out after a few hundred miles though) and I left the flywheel on correctly and moved the stator not the flywheel.

How did you find top dead center?

I timed mine with a timing light and it needed a little dremeling of the slots to get enough advance.

New ones don't need dremeling I hear

But no the flywheel should be in the stock place

I run points on my bikes so that's all I know about a cdi.

Re: Polini Tuning, Timing and I'm fucking stuck. Help!!!!

M∆®†Y Køk€š /

Treats CDI doesn't have a curve and the consensus seems that 17 degrees or 1.2mm BTDC seems to be what the polinis like. Are you running the box that comes with the cdi?

Re: Polini Tuning, Timing and I'm fucking stuck. Help!!!!

Did anyone else notice he said he has a za50 cdi on an e50

Re: Polini Tuning, Timing and I'm fucking stuck. Help!!!!

did you move the brown wire as instructed in the WIKI when putting the ZA50 cdi on an e50?

Re: Polini Tuning, Timing and I'm fucking stuck. Help!!!!

Thanks for the responses

It was timed using a timing light and a degree tape

The reason that I'm turning the flywheel rather than the stator plate is that in the stock position the moped wouldn't run at all. I flipped the flywheel to the other side and it worked so turning the flywheel was easier than tapping a new hole for the pick-up sensor.

I purchased an E50 CDI unit. I'm wondering if they sent me a za50 one on accident and if there is any difference between the za and E CDIs.

I know that the treats CDI isn't supposed to have a curve but the ignition point does shift at higher rpms. It just seems to shift in the wrong direction hence the wondering about whether it might be a za box.

Thanks again!!!

Re: Polini Tuning, Timing and I'm fucking stuck. Help!!!!

Lower your needle to get rid of the stuttering.

The new treats cdi comes with the auto retarding box. Set it to15 degrees advance at high rpm.

Re: Polini Tuning, Timing and I'm fucking stuck. Help!!!!

Benevolent Aroh /

I had a bike doing something similar because the tank was rusty. Even with an inline filter, the carb can still get gunked up.

Re: Polini Tuning, Timing and I'm fucking stuck. Help!!!!

Probably Fred /

Hey jake time to what high rpm ?

How high?

Re: Polini Tuning, Timing and I'm fucking stuck. Help!!!!

I've got mine on 1,4mm bdp and the jets try 92 to 100

I drive around with a jet 92.

Full setup of my Puch

E50 pedal version but with out pedals, they look stupid!

65cc Polini with the standard Polini membrane

15mm Bing with jet 92 and a preformance air filter

50cc HC head

Proma Warrior exhaust

15-45 sprockets

Malossi Viton powerbox

Re: Polini Tuning, Timing and I'm fucking stuck. Help!!!!

Probably Fred /

Are you running a treats cdi^^ at that timing and what rpm did you time with light .

A boost bottle does little for my setups

Looks cool though

Re: Polini Tuning, Timing and I'm fucking stuck. Help!!!!

Find true tdc first. Rotate one way until you hit your piston stop, mark the flywheel. Then rotate the other way til you hit the stop, mark that. Tdc is the middle of both marks. Once you get true tdc mark the crank tip with some yellow paint. Use a micrometer or timing tool to set your fire point btdc. I have never had much luck with a degree tape or wheel.

Re: Polini Tuning, Timing and I'm fucking stuck. Help!!!!

Probably Fred /

use a timing light

Re: Polini Tuning, Timing and I'm fucking stuck. Help!!!!

Found an air leak at the base of the intake so everything is apart right now. Smoothing and polishing all the intake surfaces (again...). I think this is the brunt of the problem. Actually I ended up re-shaping the inside casting of the polini intake while it was off so that should help with flow.

Yeah, I've been using a timing light but will also use a micrometer to set the timing perfectly once everything is all sealed up again. Hopefully this solves the problem.

Thanks everyone for your help. Will report back as soon as everything is back in one piece and running!!!

Re: Polini Tuning, Timing and I'm fucking stuck. Help!!!!

Use a resistor plug or you will burn up that CDI!

Re: Polini Tuning, Timing and I'm fucking stuck. Help!!!!

Salsa Salsa /

I had a bad treats cdi box that did this same thing. When I swaped boxes it worked perfectly.

Re: Polini Tuning, Timing and I'm fucking stuck. Help!!!!

Christian Giron /

This is relevant to my interests.

1.2mm btdc is what polini likes, but is this also a safe bet at high RPMs? What if I did 1.25-1.3mm, would this be retarding timing and lowering temps?

This is my first polini so I really want to play it safe for a little before I start going crazy

Re: Polini Tuning, Timing and I'm fucking stuck. Help!!!!

that is advancing the timing.

I ran my polinis at 1.1-1.2. 1.2 is MAX.

Re: Polini Tuning, Timing and I'm fucking stuck. Help!!!!

Alright.

I have taken everything off and re-assembled it to get rid of any air leaks.

Replaced the CDI ignition coil with a new one from Treats

Re-set the timing to be a bit more conservative

It runs a whole lot better now but it still stutters at full throttle although not nearly as bad. I have a 92 jet in there right now and I think it's getting too much fuel so I'm going to move down to about an 88 and start from there.

Oh. I also re-installed the woodruff key and moved the pick-up to the opposite side. (edited)

Re: Polini Tuning, Timing and I'm fucking stuck. Help!!!!

Shot a video of it running. First one is with the air filter:

And this one is without. It seems to run better but still stutters at full throttle near the end of the video:

Re: Polini Tuning, Timing and I'm fucking stuck. Help!!!!

Ignore the mess of wires. They have not been tucked away yet and not all of the peripherals have been hooked up yet.

Re: Polini Tuning, Timing and I'm fucking stuck. Help!!!!

Probably Fred /

Try a 90 jet 1 clip rich

Re: Polini Tuning, Timing and I'm fucking stuck. Help!!!!

I didn't finish the whole thread but you have to have timing drop off at higher rpm's the reason is you want to move the heat off the piston, and into the pipe where that will increase the pulse from the pipe making better power than the advanced timing. After the power band has passed you can put advance back in but you need a programmable cdi to do that. I think you need to nail down your tuning to match the cdi. instead of the other way around. Accept what the cdi has, and tune to that.

Re: Polini Tuning, Timing and I'm fucking stuck. Help!!!!

That frame looks pretty cool.

Re: Polini Tuning, Timing and I'm fucking stuck. Help!!!!

what is the timing in degrees win it stars to crap out?

time it to 15 degrees at high rpm

if your cdi is retarding you might not have any timing in it win it get to high rpm you can run 30 degrees of timing so long as it drops to 15 or 16 be for the pip hits it will give you amazing take off and still have amazing safe high rpm

I have a love hate relationship with cdi's win their right their sweet but win their not dam it sucks but points are amazing all the time put a set of point on and jet it then put the cdi back on and try and get it right or just leave the points and rip for 1000000000000 mils

Re: Polini Tuning, Timing and I'm fucking stuck. Help!!!!

that actually sounds like the pick up is either on the wrong side or the timing is retarding past TDC.

Re: Polini Tuning, Timing and I'm fucking stuck. Help!!!!

Cdi is suppose to move closer to TDC if it curves to hit the power band and keep cylinder cool

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