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Discussion Starter #1
Ok so I've read through all the carb posts I could find. I'm aware of the magic 2.5 turn idle mixture etc.

I dont know yet what the previous owner set it to.

Home and my commute are 200ft above sea level. This wknd I rode at 6k-7k feet. As we move into the summer most of my trail riding will be at higher elevations.

Bike ran pretty good except idle was a bit lower up there so I adjusted that. And it would shutoff sometimes when you come to a stop. Even after the idle adjustment. There may have been a surge at 50mph with lots of throttle (not necessarily wot).

Should I go tune this thing at 3k feet or is it just a tiny bit off? I'll check the mixture screw as soon as I find a tool that fits
 

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Other than living 200 feet above sea level where are you actually located?
Finish your signature.

You have inspired me to add what sea level is for me... New Rochelle, NY is 85 feet above seal level.
 

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Discussion Starter #3
Other than living 200 feet above sea level where are you actually located?
Finish your signature.

You have inspired me to add what sea level is for me... New Rochelle, NY is 85 feet above seal level.
I've tried but it wont save.

Sea level is sea level lol. But if it helps diagnose a potential problem I'm in Los Angeles.
 

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I've tried but it wont save.

Sea level is sea level lol. But if it helps diagnose a potential problem I'm in Los Angeles.
Being in LA is half of the problem! Adjusting the carb for better performance in various elevations might mess with you emission standards out there and could cause your bike to fail at inspection. Others out there might have better advice in this regard. When you adjust things to allow the engine to breath better it will likely push the exhaust emissions over the accepted limits your state requires. Try to keep track of any adjustments you make with the pilot screw so you can easily de tune it back when you have to go for the inspections.

GaryL
 

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... I'll check the mixture screw as soon as I find a tool that fits
Buy a cheap little screwdriver, hacksaw the handle down to about 1 inch, cut the shaft off at about 3/4 inch and regrind a blade to fit. That way you can adjust the pilot needle without moving the carb.
Screw it in gently to the stop and out 2.5 to start and see what that's like. I use 2 turns at 6,000 and don't bother changing at sea level. I always have to adjust the idle when changing by that much altitude.
 

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I've had this tool in my box for over 50 years and rarely ever found a use for it until the pilot screw came along. It is a ratchet off set screw driver that accepts standard driver bits. Turn the rear handle and it spins the driver head. One full turn on the handle is one full turn of the driver bit. I use a small straight slot bit that goes right up in the pilot screw hole and I don't have to be burning my knuckles to adjust the screw. For those who don't know the correct pilot screw adjustment procedure it MUST be done when the engine and carb are at full operating temperature for the best results.

GaryL

IMG_0213.JPG
 

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Buy a cheap little screwdriver, hacksaw the handle down to about 1 inch, cut the shaft off at about 3/4 inch and regrind a blade to fit. That way you can adjust the pilot needle without moving the carb.
Screw it in gently to the stop and out 2.5 to start and see what that's like. I use 2 turns at 6,000 and don't bother changing at sea level. I always have to adjust the idle when changing by that much altitude.
Yeppers...but also do this:
When you screw in the screw, precisely count how many turns before it bottoms.
That will give you a useful reference point to compare where it is to where it should be.
Don't be afraid to play with that 2.5 turns setting...that's the way it should have come from the factory and may need further minor adjustment.

"...When you screw in the screw...". What a sentence!
I did too graduate 4th grade! :)
 

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Discussion Starter #8
I've tried but it wont save.

Sea level is sea level lol. But if it helps diagnose a potential problem I'm in Los Angeles.
Being in LA is half of the problem! Adjusting the carb for better performance in various elevations might mess with you emission standards out there and could cause your bike to fail at inspection. Others out there might have better advice in this regard. When you adjust things to allow the engine to breath better it will likely push the exhaust emissions over the accepted limits your state requires. Try to keep track of any adjustments you make with the pilot screw so you can easily de tune it back when you have to go for the inspections.

GaryL
Bikes are the 1 thing we don't have to smog here.
 

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Discussion Starter #9
Pulled the plug to inspect and found 2 issues.
The spark plug wasn't even finger tight.
The gap was well above spec.

I fixed both issues and so far I haven't had the surge. Maybe the gap was so large that it didn't always produce a spark. Had cooler weather on my commute so we'll see if there was any change.

Plug looked a lil rich but ok seeing as how I was just at high elevation
 

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I plan on setting it up for easy adjustment. Either by brazing something to the needle or using a flex-jet as someone else had just done
Well, really when you get it adjusted right you may never have to touch it again....at least that has been my experience, sea level to 12,000 feet. This is NOT true for the main jet.
 
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