Re: Slowing down a Maxi that's too fast for my son.

Overpriced Parts /
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> Graham Motzing Wrote:

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

>

>

> i mean, really, a lot of the people posting on here with 10's of 1000's

>

> i think you could keep the stock crank in it, yeah the RPMs are bad for

> them but most of the damage is from increased load and heat from a kit.

> The 50cc puch kits are barely more power than stock so a clean stock

> crank should last just about forever.

No that’s a fallacy, It is the rpm that’s mostly the problem,

Cranks do not last forever just because you’re running a 50cc kit not a 70cc kit unless you run stock rpm for some puch cranks don’t even have needle bearings at the bottom big end bearing and have only teeny tiny little oil grooves in con rod at big end so very little lube gets in to big end or to the sides of the big end of the Conrod unlike the small end of the rod because it has a oil hole,

This crank (which was low mi and in great shape to begin with) got the big end of con rod side friction welded to the crank lobes when upped the RPM to around 9,000 rpm but still running the stock 50cc cylinder, It ran good full synthetic motor oil and a heavy 50 to 1 mix more like a 45 to 1 mix,

I’ve had several puch stock crank lock ups when I upped the rpm and for me it was always the big end of the rod and always same thing: Rod was friction welded to the side of the lobes something like this:

Reed type kits/cylinders take a bigger jet and have a more gas oil in air mixture into the crankcase and you may be able to get a bit more RPM out of them if you want to try before they lock up but regular piston port kits run a smaller/leaner jet so there’s less gas in the air mix and less getting to the sides of the crank so rpms need to be kept down

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Subject Written By Posted
  Slowing down a Maxi that's too fast for my son.Topic by: Jonathan Bennett Jonathan Bennett 08/15/19 08:28AM
  Re: Slowing down a Maxi that's too fast for my son.Re: Jack Rutherford Jack Rutherford 08/15/19 08:49AM
  Re: Slowing down a Maxi that's too fast for my son.Re: Buttcheeks BUZZARD Buttcheeks BUZZARD 08/15/19 09:14AM
  Re: Slowing down a Maxi that's too fast for my son.Re: EH FCC of the QCB EH FCC of the QCB 08/15/19 09:18PM
  Re: Slowing down a Maxi that's too fast for my son.Re: Dave & Bummerzz Dave & Bummerzz 08/15/19 09:44AM
  Re: Slowing down a Maxi that's too fast for my son.Re: jayson sumpter jayson sumpter 08/15/19 10:43AM
  Re: Slowing down a Maxi that's too fast for my son.Re: ***VANILLA BLUNDER*** ***VANILLA BLUNDER*** 08/15/19 05:30PM
  Re: Slowing down a Maxi that's too fast for my son.Re: Overpriced Parts Overpriced Parts 08/15/19 11:26AM
  Re: Slowing down a Maxi that's too fast for my son.Re: JBOT Admin JBOT Admin 08/15/19 11:45AM
  Re: Slowing down a Maxi that's too fast for my son.Re: Graham Motzing Graham Motzing 08/16/19 01:49PM
  Re: Slowing down a Maxi that's too fast for my son.Re: JBOT Admin JBOT Admin 08/16/19 01:56PM
  Re: Slowing down a Maxi that's too fast for my son.Re: Overpriced Parts Overpriced Parts 08/16/19 04:22PM
  Re: Slowing down a Maxi that's too fast for my son.Re: ♣Slew Foot♣ ♣Slew Foot♣ 08/19/19 03:08PM
  Re: Slowing down a Maxi that's too fast for my son.Re: scrot rash scrot rash 08/15/19 11:35AM
  Re: Slowing down a Maxi that's too fast for my son.Re: Jeff Parr Jeff Parr 08/15/19 11:50AM
  Re: Slowing down a Maxi that's too fast for my son.Re: scrot rash scrot rash 08/15/19 11:54AM
  Re: Slowing down a Maxi that's too fast for my son.Re: Daniel '' Daniel '' 08/15/19 01:25PM
  Re: Slowing down a Maxi that's too fast for my son.Re: Adam Smith Adam Smith 08/15/19 01:29PM
  Re: Slowing down a Maxi that's too fast for my son.Re: Jonathan Bennett Jonathan Bennett 08/15/19 02:06PM
  Re: Slowing down a Maxi that's too fast for my son.Re: Erik Thalman Erik Thalman 08/15/19 02:09PM
  Re: Slowing down a Maxi that's too fast for my son.Re: Jonathan Bennett Jonathan Bennett 08/15/19 02:26PM
  Re: Slowing down a Maxi that's too fast for my son.Re: Overpriced Parts Overpriced Parts 08/15/19 05:37PM
  Re: Slowing down a Maxi that's too fast for my son.Re: Richard Eberline Richard Eberline 08/15/19 06:28PM
  Re: Slowing down a Maxi that's too fast for my son.Re: Jonathan Bennett Jonathan Bennett 08/15/19 08:36PM
  Re: Slowing down a Maxi that's too fast for my son.Re: Overpriced Parts Overpriced Parts 08/15/19 10:40PM
  Re: Slowing down a Maxi that's too fast for my son.Re: scrot rash scrot rash 08/15/19 11:11PM
  Re: Slowing down a Maxi that's too fast for my son.Re: P D P D 08/16/19 09:13AM
  Re: Slowing down a Maxi that's too fast for my son.Re: Wolf Wizard Wolf Wizard 08/16/19 02:12PM
  Re: Slowing down a Maxi that's too fast for my son.Re: sogggy burritos sogggy burritos 08/26/19 09:41PM
  Re: Slowing down a Maxi that's too fast for my son.Re: P D P D 08/27/19 09:46AM
  Re: Slowing down a Maxi that's too fast for my son.Re: Mr. Duncan Mr. Duncan 08/29/19 11:06PM
  Re: Slowing down a Maxi that's too fast for my son.Re: Daniel '' Daniel '' 08/30/19 03:16PM
  Re: Slowing down a Maxi that's too fast for my son.Re: ♣Slew Foot♣ ♣Slew Foot♣ 08/30/19 08:32AM
  Re: Slowing down a Maxi that's too fast for my son.Re: ♣Slew Foot♣ ♣Slew Foot♣ 09/02/19 04:30AM

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