Stephen115's homemade kart

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Stephen115

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I'm going to try and ride my kart this weekend if i finish my brakes. Probably will barely get into 2nd but atleast i get to ride it. I'll try and take video.
 
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Jake.B

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I was working on an old 2 stoke enduro last weekend and happend to take apart the clutch. Im pretty sure your not getting enough leverage or pull space. I would go to rockymountain.com and order the shifter lever and mounting bracket for that engine. Mount it up and test it. You may need to adjust the clutch also to get it in the right position.

Rockymountain is the sight i use to get all my parts, great customer service and even better prices, Quick shipping too.
 
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Stephen115

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I called my buddy today to walk me through this clutch thing and it turns out to be the actuator. I'm going to drop it off tomorrow at his shop or Monday at the latest.

Here is a video I took so you guys can see it run. I havent had time to edit it so you can stop watching after I shut the motor off. the chain comes off so i've added a chain tensioner to my list. Enjoy!

http://youtu.be/XwQUdwRUr3A

SJ
 
sideways

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Cool build mate.

Just FYI, that extension pipe in front of the expansion chamber makes the expansion chamber ineffective, try and shorten it as much as possible if you can.

She's gona fly with an engine like that and the light frame!! I'd be getting a large stock of tyres from that guy, you'l be needing tons of them!
 
newrider3

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Stephen115 said:
I can't get any closer at this point and I've had numerous people tell me it will work
Click to expand...

They told you wrong. Expansion chambers are a specific tuned length, any changes to the geometry renders the original design useless.

You can cut the pipe and rotate pieces to different angles, as long as you don't add or remove any length or add sharp bends.
 
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Stephen115 said:
I called my buddy today to walk me through this clutch thing and it turns out to be the actuator. I'm going to drop it off tomorrow at his shop or Monday at the latest.

Here is a video I took so you guys can see it run. I havent had time to edit it so you can stop watching after I shut the motor off. the chain comes off so i've added a chain tensioner to my list. Enjoy!

http://youtu.be/XwQUdwRUr3A

SJ
Click to expand...

why don't you just shorten the chain?
 
sideways

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Stephen115 said:
I can't get any closer at this point and I've had numerous people tell me it will work
Click to expand...

They obviously don't know what they're talking about.

Every dimension in expansion chamber design is critical and is quite dependent on the dimensions of the other parts of the chamber.

As with most things, it's easier to explain with pictures or even better, animation.

Okay, so see how the rebounding pressure wave pushes the expelled fuel air mix back in? Because you've extended the header (the name for the first part of the pipe) so much, that pressure wave won't get there in time, making the expansion chamber pointless.



Your engine will run without the expansion chamber but it will have bad economy and reduced power, as well as potential reliability problems.

+1 on what newrider3 said, cut the pipe and weld it back together in a way that will fit. They're often made of quite thin metal though.

Thanks

Hayden
 
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EC1

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That pressure wave scavanges the air-fuel mixture back thru the exhaust port using sound frequencies, not back pressure. It's a 125 pipe modified to work with a 250 motor. The length of his header approximates the length of a stock 250 pipe but it looks longer because it's not curved 180 degrees.

It'll be interesting to see how well it runs - I bet it'll run pretty good.
 
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Stephen115

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EC1 said:
That pressure wave scavanges the air-fuel mixture back thru the exhaust port using sound frequencies, not back pressure. It's a 125 pipe modified to work with a 250 motor. The length of his header approximates the length of a stock 250 pipe but it looks longer because it's not curved 180 degrees.

It'll be interesting to see how well it runs - I bet it'll run pretty good.
Click to expand...

so your saying its ok? how will I know if it's hurting the motor?
 
sideways

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EC1 said:
That pressure wave scavanges the air-fuel mixture back thru the exhaust port using sound frequencies, not back pressure. It's a 125 pipe modified to work with a 250 motor. The length of his header approximates the length of a stock 250 pipe but it looks longer because it's not curved 180 degrees.

It'll be interesting to see how well it runs - I bet it'll run pretty good.
Click to expand...

To the first part, indeed. It's a common misconception that expansion chambers create back pressure or that 2 strokes need back pressure to function.

To the second part, that's like saying I can (and it will be effective) fit the expansion chamber off a CR80 to my Victa as long as I extend the header. :eek:ut:

The header is wayyyyyyyyyyyyyy to long, if the pipe wasn't originally designed for that engine, well that makes it much less likely to work too.

It probably wont damage you engine mate, but if does, it'l be in a way that will require a top end rebuild.

Thanks

Hayden
 
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