Puch Maxi 70cc kit - FAIL

So I successfully installed a treats 70cc kit on my Maxi but I didn't remember to break it in slowly. First ride, I rode the living shit of it to assess top speed. (I hadn't up jetted at this point) After that, the motor began making a high pitch squeal. I let it cool for a couple of hours. Started it again... Same sound although not quite as loud at first. Got louder after a few minutes, and slowly became almost a clattering type of sound as I coasted down a hill. Once at a stop it woundnt start and now appears to be dead although it still turns over. Any idea what may have happened? I'm hoping I will not need to repurchase a new cylinder, piston, and head.

Thanks

Jason

Re: Puch Maxi 70cc kit - FAIL

Sounds like your nightmare came true...

Re: Puch Maxi 70cc kit - FAIL

Yeap sound like time for a new kit, and learning the break in period

Re: Puch Maxi 70cc kit - FAIL

Overpriced Parts /

Yep seized from hi stock timing, low geared, hi rpm set up and not running a head temp gauge.

Timing before jetting .

Set timing 14° before top dead center that's a good starting point. if you run cool you can always run more timing.

You want to time to stay less than 400° at head temperatures otherwise you could seize . The difference in head temperatures from 14° to 17° is like 100° F after so timing low, jet correctly, gear correctly, and run a gauge if you want to keep your kit alive.

Re: Puch Maxi 70cc kit - FAIL

Ken, why 14 degrees? I shoot for 16 on e50s, 18 for ZA.

Re: Puch Maxi 70cc kit - FAIL

Overpriced Parts /

Because the lower timing the cooler and anymore then 17° is just a waste and makes for excessive heat no real gains .

So start at the bottom 14° not 17° you can add timing if you run cool.The difference between 16° and 14° can be as much as 100°F head temps@wot depending on kit/set up. Stock cast-iron cylinder any timing seems to work not blow up your top end but aluminum cylinder or kit you got to have the timing set low or be lucky with these cheap Taiwan cast kits nowadays. (edited)

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Re: Puch Maxi 70cc kit - FAIL

Ah okay... most things I've read all say 16 is the mark to hit and that temps are lowest at 16. Interesting since I know you know what you're talking about. I wonder why there's such a discrepancy.

Re: Puch Maxi 70cc kit - FAIL

#CrazyWayne™ rocks. #CrazyWayne /

If your setup and tune is golden 18deg BTDC works just fine.

If you read Kens old post you will see that backs off his timing 1deg every 6mo.

Re: Puch Maxi 70cc kit - FAIL

Dirty30 Dillon /

I run 18* on my ZA's, temps in the mid 3's.

But seriously, sounds like you exploded your kit. Be thankful it was a Kstar and not something nice.

Re: Puch Maxi 70cc kit - FAIL

Overpriced Parts /

Crazy Wayne™ rocks your Mom's sister's niece's daughter's grandma Wrote:

-------------------------------------------------------

> If your setup and tune is golden 18deg BTDC works

> just fine.

>

> If you read Kens old post you will see that backs

> off his timing 1deg every 6mo.

I move with the times unlike some fan cooled cast iron cylinder only tuners. The lower I say the better and the noobs still set timing full advance it seems.

I used to say around 1.0mm in plug hole around 15-16 some degrees btdc

but these new casting kits like Tccd (Taiwan chemical and cylinder development) kits, 72cc airsal, new casting polini kits even treats type kits are either cast in indo china and or made with inferior materials and can't hold heat so you have to throw more and more heat back in into the pipe for these to tun cool. With small stock size fins/no fan or water to cool a puch kit a hi timed, big pipe/hi rpm set up will go into the red zone quick and seize.

I say now that Hpi or retarding ignition is best .

Points ignition with these big custom pipes/hi rpm pipes can't keep these cheep ass cast kits cool.

Temp gauges don't lie. The lower the timing the cooler a kit runs. The difference in temps from 14° to 17°@ Full throttle is huge it's 50-100 degrees F

and or not sustaining a constant temperature and it just keeps climbing until seize. The difference from a seizing or not seizing is a fine line only a few temps.

I say start low and if you run cool then add timing if your cool.

Again no one absolute setting.

And again my info is for noobs not seasoned tuners, fan cooled cast iron cylinder tuners or people that like to run 449 F head temps

Re: Puch Maxi 70cc kit - FAIL

#CrazyWayne™ rocks. #CrazyWayne /

10.2 to 1 to 9.8 to 1 compreshen with good porting & blowdown on a K-Star to put the heat in the chamber out the exhaust to feed the pipe.

I can run 19* up to 10.2k with head temps of 390/405f @WOT with points.

But this thread poster is a retard so he needs to just use the pedals.

Re: Puch Maxi 70cc kit - FAIL

Overpriced Parts /

Crazy Wayne™ rocks your Mom's sister's niece's daughter's grandma Wrote:

-------------------------------------------------------

> 10.2 to 1 to 9.8 to 1 compreshen with good porting

> & blowdown on a K-Star to put the heat in the

> chamber out the exhaust to feed the pipe.

>

> I can run 19* up to 10.2k with head temps of

> 390/405f @WOT with points.

>

> But this thread poster is a retard so he needs to

> just use the pedals.

Ya right 405 F seems right.

It's too high of temperature though 450 f is seize zone so one big 1 mile up hill on a 90° day and You got 450 temps .

Ya got to tune to never have to hit 450 temps. Some cast iron honda or pug kits can handle temps like that but not these new puch kits.

My new a55 tomos with milled head for more compression never gets hotter then 280 f.

My za50 Gila magnum, destroyer pipe that ran 421 F @ 60mph on points ignition Ran faster (62 mph) and never got over 330 f @ wot with mini rotor Hpi timed @ 1.75-1.85mm in plug hole .

I got two polini '06' castings that never get over 330 f at any timing but when I put a new 2013 casting polini kit on it runs 390 degrees f @ full throttle so the new kits do make a difference in my opinion. I'm no beginner I've been kitting bikes since the 90s and never had issues with temperature the engines would let you know that they were getting hot losing power and whatnot but they never seized.

My new conspiracy theory is they make the kits cheap so you have to buy HPI ignitions or buy kit after kit.

Re: Puch Maxi 70cc kit - FAIL

#CrazyWayne™ rocks. #CrazyWayne /
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