Author Topic: KX500-KX250 manifold?  (Read 11100 times)

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Offline DoldGuy

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Re: KX500-KX250 manifold?
« Reply #15 on: December 24, 2012, 07:27:36 AM »
The early (92/93 style) kx250 manifold has the rubber "Ears" extending into the reed cage (like the KX500). I will try to get some pictures uploaded of the different years compared to the KX500 which should answer many questions, but will be after Christmas.

DoldGuy
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Offline cmotodad

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Re: KX500-KX250 manifold?
« Reply #16 on: January 02, 2013, 11:12:41 AM »
Any news on the manifolds? Thanks in Advance. Bob

Offline brooksie

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Re: KX500-KX250 manifold?
« Reply #17 on: March 10, 2013, 02:07:48 PM »
Bump...Anyone??? And while we're at it, what airbox boot should I be buying???

Cheers

Offline sandblaster

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Re: KX500-KX250 manifold?
« Reply #18 on: March 10, 2013, 03:02:50 PM »
Here's some pics comparing the 88-93 kx250 carburetor boot to the 89-04 kx500 boot

http://www.oem-cycle.com/forum/viewtopic.php?f=48&t=353&p=1065#p1065
« Last Edit: March 14, 2013, 05:37:46 AM by sandblaster »
The four stroke engine: That's one stroke for producing power and three for wearing the engine out.

Offline LundMx

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Re: KX500-KX250 manifold?
« Reply #19 on: March 14, 2013, 05:09:26 AM »
so with your knowledge in this manner, what do you think would work best with an 1988 kx500 motor and an 09-11 kx250f chassis? i need somewhere to start
LundMx

Offline brooksie

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Re: KX500-KX250 manifold?
« Reply #20 on: March 14, 2013, 11:48:37 AM »
so with your knowledge in this manner, what do you think would work best with an 1988 kx500 motor and an 09-11 kx250f chassis? i need somewhere to start

Me too. And the airbox boot...

Offline cmotodad

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Re: KX500-KX250 manifold?
« Reply #21 on: March 14, 2013, 12:12:46 PM »
Thanks for the photos to compare. The 250 manifold I have has the wings like the 500. I made a reed spacer with @ .050 taper to help move the carb away from the shock spring (pipe side thicker). I do not think it will affect the flow into the cylinder enough to notice.

Offline LundMx

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LundMx

Offline LundMx

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Re: KX500-KX250 manifold?
« Reply #23 on: March 14, 2013, 06:02:16 PM »
So an 88-93 kx250 manifold, a custom cut spacer and what airboot do you recommend to try first?
LundMx

Offline cmotodad

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Re: KX500-KX250 manifold?
« Reply #24 on: March 15, 2013, 03:15:53 AM »
After reading some posts on the KX250F builds, it looks like they are close to the shock too. I tried to taper the reed spacer to help carb to spring clearance. It was a no go, it pushed the carb further back into the spring. I am now try to heat the manifold while spacing it away from the spring. Right now I have @ 3/32' from the spring but would like more. I may end up making a manifold (like Boyseen).
« Last Edit: March 15, 2013, 09:38:05 AM by cmotodad »

Offline brooksie

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Re: KX500-KX250 manifold?
« Reply #25 on: March 16, 2013, 02:30:45 PM »
I managed to get my engine in the frame tonight. I fitted the carb to see what the clearance to the shock was like. Seems pretty good. But I had a quick measure up of the manifold anyway. On the front left corner of the carb, there is only 4mm gap to the manifold. So a shorter manifold, or one that kicked the carb more to the left would not be practical. (This is on the standard KX500 manifold)

One issue I didn't forsee. There isn't enough clearance to fit fit the clutch cover with the engine in the frame. So I'll have to remove the engine bolts and tilt the engine forward to get it on.

Once again, if somebody can suggest which airbox boot to use???

Offline cmotodad

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Re: KX500-KX250 manifold?
« Reply #26 on: March 16, 2013, 02:48:14 PM »
I have the same clutch cover issue with the CRF frame. That is why I made a removable cover for it.