Playing with puch

This maxi has been really fun to build up. I used to suck at building one speeds cuz I came at them the wrong way. You gotta finess an e50, can't force your will on it. I understand the e50s nature now. It's true essence.

I purposely made this treats reed especial into a torque monster, then geared up.

Ported without changing much in the way of timings, just made it flow wayyyy better. Massive intake window in piston, modded skirts, under piston smoothing (love this), made it have 65% of bore width for exhaust. Decked cyl and modded head for less compression. Made a straight shot intake that coincidentally I found one exactly like it on treats after I made this one, oh well, was fun to make.

Treats cdi setup with my a3202 box that I love.. Had to chop up that stator plate to get the timings way more advanced by lengthingbthe slots and swiveling the pickup even.

Climbing my mountains with 18/40 and it just doesn't give a fuck, could go taller.

Running a 19mm phbg clone and a side bleed estoril.

Will be sad to see it go to my buddy but it's been fun

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Re: Playing with puch

I know you didn't leave the clutch alone. What crazy thing did you come up with?

Re: Playing with puch

It was previously lightened but very low engagement. Torque monsters don't need any kind of stall.

Re: Playing with puch

I've read stuff about that bridge in the intake and removing it, and my take is leave it in, but round it to flow better.

The only gains you'd get by removing it can be made up by porting the piston window way higher like I did, which gives you 360deg of intake timing really easily. And in my experience here, 360deg intake doesn't seem to affect the width of the powerband at all. Only the blowdown seems to matter in that regard.

Re: Playing with puch

Alan Jackson /

good stuff, I see your spark plug protrudes into the combustion chamber a few mm. is that by design or by accident? also do you or anyone else bother with indexing the plugs with washers/shims so the gap faces the "right" way?

Re: Playing with puch

Hey jbot. Can you post some more internal smoothing pics. Very interested to see some. I’ve done mine but feel I could go further

Re: Playing with puch

Brandon Weiss (Detective brandon to you) /

I really like those pipes, they have great low end and mids, and pretty quiet too. I ran one for a little while, but then switched to a treats pipe.

But there's someone on here that doesnt like them....supposedly they put too much heat back into the cylinder? I can't quite put my finger on who had said it......i've heard it so many times by now i feel like i should know who it was. Well, we'll see, should come along any minute now

Re: Playing with puch

Roff don't like sidebleed, but who cares? I run 90% of my bikes with sidebleeds. They rule. Quiet, hit hard, can also add end bleed, what's not to love? Besides, running a retarding Cdi allows plenty of cooling.

That plug shot was after turning it on the lathe. Not the way it's set up on a bike, had no washers on the plug. As well, I don't fuck with indexing, don't care that much, just had to lose a lil comp on that head.

The under piston smoothing is what you see in the pic, the transition from around the piston wristpin holes, I make it almost look organic between the inside of piston to the transfers so the flow just fucking goes. It's the one spot almost everyone overlooks. (edited)

Re: Playing with puch

Brandon Weiss (Detective brandon to you) /

> JBOT Admin Wrote:

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

> Roff don't like sidebleed, but who cares? I run 90% of my bikes with

> sidebleeds. They rule. Quiet, hit hard, can also add end bleed, what's

> not to love? Besides, running a retarding Cdi allows plenty of cooling.

>

> That plug shot was after turning it on the lathe. Not the way it's set

> up on a bike, had no washers on the plug. As well, I don't fuck with

> indexing, don't care that much, just had to lose a lil comp on that

> head.

>

> The under piston smoothing is what you see in the pic, the transition

> from around the piston wristpin holes, I make it almost look organic

> between the inside of piston to the transfers so the flow just fucking

> goes. It's the one spot almost everyone overlooks.

yeah, i know...i was being vague for comedic effect. mustve been too vague

i too love me some sidebleed action

Re: Playing with puch

Nice! When you say very low engagement on the clutch, how low are we talking?

Re: Playing with puch

The side bleed does kick ass. Besides the cooling effect, would end bleeding give you more rpms? Are there any other benefits to be had? I ask because i have an side bleed estoril on a A55 and a e50. When i tried end bleeding the tomos i didnt really notice a difference except the noise. iam just discovering the nuances of 2 stroke tunning so maybe iam missing something.

Re: Playing with puch

Brandon Weiss (Detective brandon to you) /

> Alex hernandez Wrote:

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

> The side bleed does kick ass. Besides the cooling effect, would end

> bleeding give you more rpms? Are there any other benefits to be had? I

> ask because i have an side bleed estoril on a A55 and a e50. When i

> tried end bleeding the tomos i didnt really notice a difference except

> the noise. iam just discovering the nuances of 2 stroke tunning so maybe

> iam missing something.

Depends on the setup. I had the A55 side bleed getting me to 52mph with the block off screw, and 53mph with no screw in there at all.

Re: Playing with puch

Overpriced Parts /

> JBOT Admin Wrote:

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

> Roff don't like sidebleed, but who cares? I run 90% of my bikes with

> sidebleeds. They rule. Quiet, hit hard, can also add end bleed, what's

> not to love? Besides, running a retarding Cdi allows plenty of cooling.

>

> That plug shot was after turning it on the lathe. Not the way it's set

> up on a bike, had no washers on the plug. As well, I don't fuck with

> indexing, don't care that much, just had to lose a lil comp on that

> head.

>

> The under piston smoothing is what you see in the pic, the transition

> from around the piston wristpin holes, I make it almost look organic

> between the inside of piston to the transfers so the flow just fucking

> goes. It's the one spot almost everyone overlooks.

Yeah I run static points ignition so hotter running pipes like sideBleed aren’t the greatest fo me but if you have any kind of retarding ignition they can work fine once tuned,

Matter of fact the fastest I got my za50, 74cc gila, 24 tm, magnum was with the MLM side bleed @ 64mph on the flat but head temps went to 432f very quick

Re: Playing with puch

Chöschi21 C.K. /

How steep are "Your Mountains"?

Re: Playing with puch

Brandon Weiss (Detective brandon to you) /

> Chöschi21 C.K. Wrote:

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

> How steep are "Your Mountains"?

Giggity

Re: Playing with puch

Kevin Bishop /

I guess there is no way of balancing that piston with such a large window. It should be fun while it lasts! Pic of the exhaust? Aux ports? What kind of bit did you use on the drill press for decking?

Re: Playing with puch

What kind of exhaust timings and blowdown make for a "torque monster"? under 170°?

Re: Playing with puch

> Chris Straub Wrote:

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

> Nice! When you say very low engagement on the clutch, how low are we

> talking?

Very low.

Lightened shoes stock springs.

It's off the clutch very very fast. Sounds like 3 or 4K?

Re: Playing with puch

> Kevin Bishop Wrote:

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

> I guess there is no way of balancing that piston with such a large

> window. It should be fun while it lasts! Pic of the exhaust? Aux ports?

> What kind of bit did you use on the drill press for decking?

I've run pistons with bigger windows like this for years.

It's not an issue. I run them at full rpm all the time. So unless you've done this and had problems, maybe zip it? Don't promote myths.

No aux ports, no good on one speeds with low timing. No way.

It's a mill that decked the cyl

Re: Playing with puch

> patrick stover Wrote:

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

> What kind of exhaust timings and blowdown make for a "torque monster"?

> under 170°?

I didn't touch timings.

So whatever the treats reed ex and blowdown is, that's what makes a torque monster, along with a hard hitting low end pipe, and lots of easy flow

Re: Playing with puch

Modded treats stator for advanced timing with the a3202 box.

modifying the trigger and the stator trig housing to get the timing where I need it. Worked by swiveling the trigger and modifying the end of the coil to not hit the flywheel.

Ended up with 20deg, retarding down to 15 at higher rpm.

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Re: Playing with puch

Settled on a 106 main, and a w7 on the second most richest position on a 19 phbg clone

Re: Playing with puch

Kevin Bishop /

Just saying your window could of had a bridge. I never said you didn't have skills. Midol works wonders.

Re: Playing with puch

> Kevin Bishop Wrote:

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

> Just saying your window could of had a bridge. I never said you didn't

> have skills. Midol works wonders.

This isn't about me.

This is about you.

You implied that large windowed pistons are a problem.

So a bridge would solve this balance issue you're talking about?

Tell me more. How would it help?

I'm all in for truth when discussing 2t mods, with real world reliability and performance in mind. No bullshit tolerated

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TRLL ME KEVIN I GOTTA KNOW WTF HSPPED TO YOYR WINDIWED PISTON DOD IT BLOW UP OR DOD IT GET UMBALANCED OR DID IT FUCKING RIP OR WETE YOU JUST SAYING YHINGS THST YPU HSVE ZERO EXPERIENCE OR EVIDRNCE TO SUPPORT SO BASICSLLY LYING I HATE LIARS SO NO FUCKING MERCI BOIIIII

Re: Playing with puch

FUCK A BRIDGE, MORE AIR DA BETTER!

Re: Playing with puch

Porting is killer. I do dumb shit like adding notches to the skit and raising/ winding the exhaust. But something about making a big window I an a piston is always winning.

The decking is killer. Love it! Low clutch stal and power for the win!

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(edited)

Re: Playing with puch

Kevin Bishop /

I am only saying that in production Reed motors like an A35 or RD250 their pistons have conservative windows. They have stood the test of time for 30+ years. Millions of dollars of engineering developed them to work this way to their optimum performance and reliability. The Rd250 went from 10bhp to 60bhp just by simple modification. Same motor just different porting of the cylinder and piston. Fractions of mm's doubled hp and shapes of ports were the key not size. Ovals, squares with rounded corners and trapezoidal ports worked best for flow. I have even seen a teardrop shape.

It is evident in the polini piston that is cast to be balanced due to its aggressively ported channels. But you know that. You are just looking for a fight, dog. Relax a little. I never said it wouldn't work or go fast. Race cars go fast just have to be rebuilt slot.

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