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jetting single carb from sea level to 2000ft


hp2000

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So I live at around sea level in California and want to go ride in Gorman (hungry valley) and was wondering how much my jetting needs to change. As of now this ia how it sits:

 

Single 38mm pwm

200 main

58 pilot

Neddle in middle 3rd don't remember needle type

Timing +5

Stock cdi

Race ported

Cool head 19cc domes on 370 long rod kit.

Compression at 175

T5 pipes.

 

Any info to make this easier would help thank you.

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So I live at around sea level in California and want to go ride in Gorman (hungry valley) and was wondering how much my jetting needs to change. As of now this ia how it sits:

 

Single 38mm pwm

200 main

58 pilot

Neddle in middle 3rd don't remember needle type

Timing +5

Stock cdi

Race ported

Cool head 19cc domes on 370 long rod kit.

Compression at 175

T5 pipes.

 

Any info to make this easier would help thank you.

 

 

 

 

i read in the jetting forum, go up a full jet size every 500ft. example i was givin (500ft-160 main)(1000ft-170 main) hope that helps

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The above is misinformation.

 

The air gets thinner when you go up in elevation,

so you have to lean it out!

 

I have a mostly stock bike except for my Trinity Racing 2 into 1 34mm PJ Keihin,

K&N pod filter and my Paul Turner mids.

 

My bike did well with a 182 Main at Pismo, (sea level).

 

Went to Sand Mountain, NV (4000 ft) and I couldn't pull 4th gear up the mountain where the peak is ~4500 ft.

 

Dropped down to a 175 Main and I was able to pull 4th no problem.

 

2 weeks later I was back down at Pismo bike was an absolute beast.

 

It would pull the front tires up rolling the throttle on in 3rd.

 

I ripped on it pretty hard and never got above 160*F.

 

Do your research.

 

IIRC, for every 1700ft up in elevation you go you're supposed to go down 1 Main Jet size, example, 182 to 180.

 

Is your bike dyno tuned at sea level?

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well if thats true then my bike and my builder must be fucked up cause when i go from my house to the dunes i follow the guidline i gave and go up with the elevation and the performance gets better. just say. now the elevation change isnt as drastic as whats being described but there is a difference so i guess its all prefference

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well if thats true then my bike and my builder must be fucked up cause when i go from my house to the dunes i follow the guidline i gave and go up with the elevation and the performance gets better. just say. now the elevation change isnt as drastic as whats being described but there is a difference so i guess its all prefference

 

http://www.google.com/#q=two+stroke+jetting+and+elevation

 

Think about it man, air gets thinner with altitude so less oxygen is available, so less fuel is required so leaner jetting is required.

 

This thread should put any questions you or your engine should have about jetting and elevation.

http://www.horizonsunlimited.com/hubb/suzuki-tech/high-altitude-carb-jetting-8431

Edited by Strm Trpr
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http://www.google.com/#q=two+stroke+jetting+and+elevation

 

Think about it man, air gets thinner with altitude so less oxygen is available, so less fuel is required so leaner jetting is required.

 

This thread should put any questions you or your engine should have about jetting and elevation.

http://www.horizonsunlimited.com/hubb/suzuki-tech/high-altitude-carb-jetting-8431

 

 

 

 

srem trpr is correct. i taled to my guy again and read up some more info. and they were baising it off of humidity as well and the elevation change from chicago to silver lake isnt that much of a difference. my bad

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