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XR250 Pumper carb

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Is there a pumper carb for the XR250 ?

I have the edelbrock on my XR400 but i don't recall seeing a Mikuni or an Edelbrock for a 250

 

thanks

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If you have a modified engine 280 or similar you can use the TM 36 like i did .

But it's a lot of work as the TM36 don't fit in between Cylinder and Frame at the installation .

The subframe Airbox and shock must be removed then the Carb can be installed and everything goes back on .

Makes jetting a nightmare but done , well worth it.

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ok thats interesting

i was toying with a 280cc upgrade while its in bits

 

is this a good way to go ?

 

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seems like xr250l car has the pumper but is restrictive in other ways.

i think i'll still with the stock carb for starters and see how it goes. I expect i'll jet it richer too.

 

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5 hours ago, FFMan said:

seems like xr250l car has the pumper but is restrictive in other ways.

i think i'll still with the stock carb for starters and see how it goes. I expect i'll jet it richer too.

 

Seems like everything but the bowl and main jet will swap from the 250R carb. 

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Its a completely different carb. I feel like they got it backwards, but yes the xr250l has an accelerator pump. The xr250r doesn't. Get an L carb and it should fit that frame.
Or put an fcrmx on it and write a thread on it.
Brap braaap

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..Or you could read the link I posted. 

I dont know how much a more shallow bowl would hinder performance but if all the other restrictive parts can be swapped with 250R stuff it would be pretty sweet bolt on upgrade.  

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I'm assuming your hoping a carb swap will net more power?
We've used octane booster or power booster with good results.
It's much easier and you can stop using at anytime to get back to normal power.
Just use it sparingly, read the instructions, we destroyed an XR100 head using too much.
You can buy it at Walmart.
 

turbo108octaneboost2.png

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I'm pretty sure octane booster doesn't give you more power. Anything under 11:1 should run good on 93 pump gas. You only need high octane for high compression motors. The high octane protects the motor from detonation

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Sudco has a bolt on 35mm   pumper carb for the late Xr250r. Many years ago I tested it stock xr250 and my xr300. Off idle snap,mid range great over my Flat slide 34mm.Problem flat on top end since this was many years ago. Im sure someone has it dialed in by now.

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