Maxi N not running right. (Ported)

Chöschi21 C.K. /

So, we Recently modified a stock Maxi N, it's not mine, it's a friends, we put on a Ported cylinder i still had laying around(Pics following). Setup right now is:

-Stock filter with Tube removed

-12mm Bing, 62 Jet

-Ported stock 1.2hp restricted Cylinder 143°intake/114°Transfer/164°Exhaust

-Stock head, modified for 1.5mm Squish

-Techno Stock look 28mm Exhaust with stock Silencer

-Stock 13:45 Gearing

-Ducati 6v17w Points Ignition from a later Model Supermaxi, Points open 18°btdc

It's running fine, pulls a little less and is a minimal amount slower than my stock Supermaxi, it doesn't want to go faster than about 30kmh(18mph), wich is strange, because it did about 30-35(18-20mph) stock.

Tried jets from 48-64, no Air leaks of any kind, Ignition fires right and everything, it just doesn't want to go faster. we tried for nearly two days now with little to no progress.

Re: Maxi N not running right. (Ported)

Chöschi21 C.K. /

Pics of cylinder before cleaning and Installing it:

20190601_220202.jpg
20190601_220215.jpg
20190601_220224.jpg

Re: Maxi N not running right. (Ported)

Chöschi21 C.K. /

Pics of piston before cleaning and Installing:

20190601_220244.jpg
20190601_220251.jpg
20190601_220256.jpg

Re: Maxi N not running right. (Ported)

Overpriced Parts /

Kinda crappy gearing, with that non chamber pipe you’ll be lucky to get 6,500 RPM out of it

Try 15x45 gears at least and try a 212a atomizer and mesh filter or no filter

but ya over the years I took boxes of those 1hp restricted cylinders to the scrap yard! to me they’re worthless

Re: Maxi N not running right. (Ported)

Chöschi21 C.K. /

> Ken Roff Wrote:

> -------------------------------------------------------

> Kinda crappy gearing, with that non chamber pipe you’ll be lucky to get

> 6,500 RPM out of it

>

> Try 15x45 gears at least and try a 212a atomizer and mesh filter or no

> filter

Definitely not, the Pipe should be good enough to get to 50-55kmh, 212a Atomiser is stock, Filter definitely isn't the Problem, and the 13:45 Gearing is fine, this thing should be able to climb hills. This thing should be able to get up to at least 45kmh with that setup but doesn't.

Re: Maxi N not running right. (Ported)

Overpriced Parts /

> Chöschi21 C.K. Wrote:

> -------------------------------------------------------

> > Ken Roff Wrote:

>

> > -------------------------------------------------------

>

> > Kinda crappy gearing, with that non chamber pipe you’ll be lucky to

> get

>

> > 6,500 RPM out of it

>

> >

>

> > Try 15x45 gears at least and try a 212a atomizer and mesh filter or no

>

> > filter

>

> Definitely not, the Pipe should be good enough to get to 50-55kmh, 212a

> Atomiser is stock, Filter definitely isn't the Problem, and the 13:45

> Gearing is fine, this thing should be able to climb hills. This thing

> should be able to get up to at least 45kmh with that setup but doesn't.

Try it without the junk square airbox, run a metal mesh filter or no filter and re jet it trust me it will run better, you can try the 222 atomizer too but do nothing with the square airbox

Re: Maxi N not running right. (Ported)

Chöschi21 C.K. /

Tried out without the Airbox, but i run the same kind of Airbox on my Maxi with a 15mm Bing and 65cc Airsal and i get up to about 60kmh with the same Gearing, similar Setups run 50ish with stock Airboxes, i always run the Stock airbox and never really had a problem. Could the Porting just be off? Never ran these Narrow kind of ports with those fairly high Timings. But even then it should at least be faster than Stock.

Re: Maxi N not running right. (Ported)

Chöschi21 C.K. /

Just noticed that i forgot to add the Portmap:

20190601_220059.jpg

Re: Maxi N not running right. (Ported)

Way too much intake timing.

Re: Maxi N not running right. (Ported)

u need piston rings.

Re: Maxi N not running right. (Ported)

Chöschi21 C.K. /

> Daniel '' Wrote:

> -------------------------------------------------------

> Way too much intake timing.

Really? I normally go for about 120-130°, but 140 worked fine for me before all the time.

Well, tried around a little today, opened up the Airbox and removed the inner walls, even tried without the Mesh filter, i got it to about 35kmh with a 66 Jet, id say that is still far to low.

Re: Maxi N not running right. (Ported)

Overpriced Parts /

> Chöschi21 C.K. Wrote:

> -------------------------------------------------------

> > Daniel '' Wrote:

>

> > -------------------------------------------------------

>

> > Way too much intake timing.

>

> Really? I normally go for about 120-130°, but 140 worked fine for me

> before all the time.

>

> Well, tried around a little today, opened up the Airbox and removed the

> inner walls, even tried without the Mesh filter, i got it to about 35kmh

> with a 66 Jet, id say that is still far to low.

Ya got to Pitch the stock air box completely it’s square and causes turbulence

Re: Maxi N not running right. (Ported)

12mm intake? too small,Chosh.

Re: Maxi N not running right. (Ported)

Chöschi21 C.K. /

> Don Ohio Wrote:

> -------------------------------------------------------

> 12mm intake? too small,Chosh.

No, opened up 12mm, as close as i could get it to the Port without breaking through.

Re: Maxi N not running right. (Ported)

Nothing wrong with the stock airbox and 12mm. You can easily go 60 kmh with those. Have you checked if the brakes are dragging?

Re: Maxi N not running right. (Ported)

Chöschi21 C.K. /

> Bas Autowas Wrote:

> -------------------------------------------------------

> Nothing wrong with the stock airbox and 12mm. You can easily go 60 kmh

> with those. Have you checked if the brakes are dragging?

Yep, have checked that and nope, they don't.

Re: Maxi N not running right. (Ported)

Your intake timing wants to make peak power above 10k, but your transfers say no way. Also a blow down at 25° is kinda high for a stock pipe so any powerband you might have is gonna be pretty weak.

Re: Maxi N not running right. (Ported)

Jack Hernandez /

Did you case match your kit? Any sharp angles in the transfer ports create eddies in the flow and enough of them flood your bike not allowing the fuel to reach the combustion chamber. Also, with the squish you added, a stock pipe is working against you. Get some expansion chamber involved for gods sake.

Re: Maxi N not running right. (Ported)

OG Crazy Wayne /

The only thing you can do is shim the cylinder up at the base 1 to 1.5 millimeters.

Then your timings will be close to.

136/138 intake, 120/122 transfer, 170/172 on the exhaust.

Ditch the head gasket and spend some time sanding the cylinder down tell you have a squash of .7 millimeter.

Try to raise the transfer ports so you have a blow down closer to 20 to 22°

And put a little promo pipe on it and you'll have lots of fun 18 degrees on the spark timing.

If you can find a 1.5 or 2 mm countersunk head then you won't need to cut the deck of the cylinder down (edited)

Re: Maxi N not running right. (Ported)

Yeah, Wayne nailed it. Get those transfers up to +120 with a spacer and I think you would be making a lot more power. I have decked a kit with an angle grinder before, I put the chuck in the middle and held the cutting disc mostly flat. Then finished it on our lapping block. I took 4mm off a cast Iron liner magnum cylinder with ease.

Re: Maxi N not running right. (Ported)

OG Crazy Wayne /

As a rule of thumb an intake timing should never exceed 120% of transfer Port timing.

Some run as much as 125% but that's on a full race set-up that has a clutch not kicking in till at least 7,000 RPM.

And they might need a weed blower to push air through the carburetor to get the thing started.

115% will give you the best all-around performance without too much gas spitting on your pant leg

Re: Maxi N not running right. (Ported)

Chöschi21 C.K. /

Well, we looked into it, or rather, i did, he put the Piston in the wrong way, witch means that the Transfers weren't opening as they should and the Intake wasn't quite open and lower than 140°, runs even worse than before, he told me that it got worse every time he rode it, so i checked the Ignition Timing, i set it to 18°, now it's at 2, the Point's burned out, put new ones in, plus condenser, 20° now, runs fine, haven't checked ho fast, but if i could guess id say it's about 50kmh/9'000rpm right now.

Re: Maxi N not running right. (Ported)

OG Crazy Wayne /

Band-Aids and bullet holes you're a fucking Jake Meister sorry I wasted my fucking time trying to help your dumbass

Re: Maxi N not running right. (Ported)

Chöschi21 C.K. /

Yea, fuck you to.

After a couple of drives up and down the Street it lost power again, cold the sane, runs the same as before. Timing is the Same as before.

Re: Maxi N not running right. (Ported)

Overpriced Parts /

> Chöschi21 C.K. Wrote:

> -------------------------------------------------------

> Yea, fuck you to.

>

> After a couple of drives up and down the Street it lost power again,

> cold the sane, runs the same as before. Timing is the Same as before.

Yeah that nut case is crazy Wayne!

He’s been thrown off this website at least a dozen times cause he is a troll!

He’s an idiot knows nothing about a puch even if one was thrown on his head!

There was a post where some girl had him work on her Maxi and he completely molested it! didn’t run for shit!

He worked in a chainsaw shop for a few months as apprentice as and now he’s an expert on 2 stroke engines (not) !

He’s as dumb as a box of rocks when it comes to a 1 or 2 speed puch!

I got quarter million miles on two wheel 2 stroke bikes (never owned a 4 stroke motorcycle in my life) and thousands of hrs on 2 stroke outboard motor boats plus worked on 2 stroke outboards at a marina !

Got 2,000,000 plus mi on 4 to 18 wheels vehicles (including tractors and farm equipment) including gasoline and diesel powered! does he ? nope he is Just a troll?

He is a is lonely troll that never had a family whereas my family/my three children and my wife both participated in Moped‘s, enduro bikes, outboard boating, performance cars/quarter-mile drag racing, conversion/Rv vehicles and everything !

This goof couldn’t even get out of his own way! I mean he said ! (you could find his post here) to run a 70cc treat kit at 19° Timing and when it gets to 420° Head temps to shut it down and put on the choke!

how the hell could you do that when there’s a truck any other vehicle on your ass going onto a State Route at 50-55 miles an hour!

That right there means he don’t know shit about anything!

Hopefully soon the mods will take away this seventh or eighth profile he made here but even if they don’t I’m kind of glad he’s here because we need entertainment!

Re: Maxi N not running right. (Ported)

Chöschi21 C.K. /

Cleaned the Carb for the third time, nothing changed, runs rougher than before, just for fun lowered the Squish to 0.9mm, it got a little better, but not by much, removed the Ignition again and put another one in witch works.

Won't test it, going to sleep, its 12:23AM, maybe gonna try tomorrow.

If it won't work im going to try the old Setup i had on my Maxi witch i know runs 45kmh, it's:

Stock 1.2hp Cylinder with am small cutout to up Intake timing a bit,

12mm Bing with 56 Jet, opened up Stock filter, 22mm Exhaust with short Header.

If that doesn't work i at least know that it's not the Setup.

I kind of feel Stupid right now.

Re: Maxi N not running right. (Ported)

Chöschi21 C.K. /

Okay, now i don't know what to do anymore, Checked if the Wheels rotate Freely, if there is enough gasflow from the Tank to the Carb, checked for Leaks. Put on the 65cc Airsal with Accessoires from my Maxi, nothing, there is no change in Topspeed.

Re: Maxi N not running right. (Ported)

Chöschi21 C.K. /

Fuck this thing, put it back together with him 2 Days ago and it runs fine, setup as seen above but with a smaller Squish, goes 50kmh(32ishmph).

Re: Maxi N not running right. (Ported)

OG Crazy Wayne /
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