Author Topic: crank stuffer  (Read 27908 times)

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Brett

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Re: crank stuffer
« Reply #60 on: January 02, 2008, 06:01:24 PM »
Aren't those conrods just for 4 strokes?
Shouldn't exhaust ports be flat on the top to make sudden pulse.

Offline bigbellybob

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Re: crank stuffer
« Reply #61 on: January 03, 2008, 09:30:16 AM »
I guess a upside down triangle is a bad description It is a trapezoid. The idea is to have the left and right port walls get slightly closer together towards the bottom. when the piston first starts to uncover the port the gasses are under high pressure so it comes out fast but as more and more of the port is uncoverd the pressure drops and the gasses slow down. the idea is if the port narrows towards the bottom the gasses keep moving fast even though the pressure is droping.It's like when the river is wide the water flows slow but when the river narrows the water moves faster. Yes I'm sure the port has to flow less but this should make great bottom end torque and mid range. I want to make up for this with larger secondary exhaust ports but I do not think this would have that great of an impact on top end because we are not talking about making the port a lot smaller and by the time the port opens all the way It has allready done the vast majority of its flowing.

BDI is this close to what your talking about. the top would be stock and the bottom a BDI mod.
« Last Edit: January 03, 2008, 09:32:12 AM by bigbellybob »
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Offline BDI

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Re: crank stuffer
« Reply #62 on: January 03, 2008, 10:54:27 AM »
I guess a upside down triangle is a bad description It is a trapezoid. The idea is to have the left and right port walls get slightly closer together towards the bottom. when the piston first starts to uncover the port the gasses are under high pressure so it comes out fast but as more and more of the port is uncoverd the pressure drops and the gasses slow down. the idea is if the port narrows towards the bottom the gasses keep moving fast even though the pressure is droping.It's like when the river is wide the water flows slow but when the river narrows the water moves faster. Yes I'm sure the port has to flow less but this should make great bottom end torque and mid range. I want to make up for this with larger secondary exhaust ports but I do not think this would have that great of an impact on top end because we are not talking about making the port a lot smaller and by the time the port opens all the way It has allready done the vast majority of its flowing.

         

BDI is this close to what your talking about. the top would be stock and the bottom a BDI mod.

   Yep just like that.
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Offline maddoggy

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Re: crank stuffer
« Reply #63 on: January 03, 2008, 11:04:43 AM »
brian, that makes good sense to me. i think you're on to something here. it could work, when are you going to try it?  MADDOGGY

Offline BDI

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Re: crank stuffer
« Reply #64 on: January 04, 2008, 12:26:54 PM »
As soon as I can find a good cylinder to build the way I want. It will probably be a while though because I want to build a stroker crank too and the cylinder will have to be built to suit the stroked crank.
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Offline kaw rider

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Re: crank stuffer
« Reply #65 on: January 04, 2008, 04:04:34 PM »
bdi
who's going to do the crank for you.

Offline doordie

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Re: crank stuffer
« Reply #66 on: January 20, 2008, 07:16:25 AM »
Aren't those conrods just for 4 strokes?
You can order for anykind of bike(2t or 4t),just measure and let them fabricate one. :wink:

Just 1000$ :-D
« Last Edit: February 01, 2008, 11:22:05 PM by doordie »
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Offline BDI

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Re: crank stuffer
« Reply #67 on: January 20, 2008, 04:37:06 PM »
You know looking at the size of the rod It is going to displace more air in the bottom end and drive up the primary C.R.
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Offline kaw rider

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Re: crank stuffer
« Reply #68 on: January 20, 2008, 06:04:21 PM »
check out this saw.

Offline BDI

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Re: crank stuffer
« Reply #69 on: January 21, 2008, 03:51:35 AM »
check out this saw.
What kind of horse power is it putting down at the chain :lol: :lol: :lol: :lol:
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Offline doordie

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Re: crank stuffer
« Reply #70 on: January 22, 2008, 01:04:46 AM »
this cylinder kips have more travel then the stock kips do. toke some time but worth it.

How did you do that?  :-o
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Offline kaw rider

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Re: crank stuffer
« Reply #71 on: January 22, 2008, 02:13:08 AM »
doordie
i'm running 162* to 192* with kips. takes alot of time to do. i have about 15 hours in invested, but the next one i do i can do in about 7 hours. stewart cut .020 off base.
great pull from 4500 to the moon. i think stock  168* to 182* exhaust timing.
BDI
he has seen my exhaust port set up. i'm working on some other great  cylinder set ups. these engines when design made for 3500-6000 rpm range.

Offline doordie

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Re: crank stuffer
« Reply #72 on: February 01, 2008, 11:20:04 PM »
doordie
i'm running 162* to 192* with kips. takes alot of time to do. i have about 15 hours in invested, but the next one i do i can do in about 7 hours. stewart cut .020 off base.
great pull from 4500 to the moon. i think stock  168* to 182* exhaust timing.
BDI
he has seen my exhaust port set up. i'm working on some other great  cylinder set ups. these engines when design made for 3500-6000 rpm range.

You,BDI,Steward and some others are serious tuners at this forum,glad to be a part of this mission to make K5 to a greater bike! 8-)
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Offline kaw rider

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Re: crank stuffer
« Reply #73 on: February 14, 2008, 10:29:29 AM »
bearings

Offline mdw471

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Re: crank stuffer
« Reply #74 on: February 15, 2008, 06:42:04 AM »
kaw rider

are the balls (in your bearing) ceramic?

Mark
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