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Discussion Starter · #1 ·
1000ft ASL
25 Pilots
2.5 turns on screws
Clips on middle postion
155/160 mains

Mods are: no lid with K&N air filter and outwears cover, no spark arrestor on stock pipe, cleartube tuned, trimmed float stops.

Idles good, and seems to rev ok (it doesn't pop or stumble but I still don't think it's perfect) up to 3/4 throttle but then starts popping. I tried going up and down with the clip and that didn't improve anything, and I went up from 150/155 mains to my current set.

The carb bowls don't need to be bled out or anything when reconnecting the tank do they?

I'm almost wondering if I should buy a wideband o2 gauge and hook it up to make things simpler.
 

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Re: Jetting problems. (continued)

If it's popping, you're probably running lean since you are running without the lid on.

If you plan on buying an exhaust soon, the problem will be solved.

~Brian
 

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Discussion Starter · #3 ·
Re: Jetting problems. (continued)

I guess I'm surprised that I would still be running lean with 155/160 mains and I don't even have a pipe. :help:
 

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Re: Jetting problems. (continued)

are these stock needles? If so, I never have any luck getting modified engines to run well on the stock needles but do have good luck with the gyt-r needles. With gyt-r needles, I'd say you need 3 or 4th clip and 160/165 mains.
 

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Discussion Starter · #5 ·
Re: Jetting problems. (continued)

Oh ok, so my mains are still too small? Jeeze, ok. I'll head over to the stealership and get a 165 and inquire about the gytr needles.
 

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Re: Jetting problems. (continued)

Jetting is not my thing by any means, but when you change the mains your also changing the mid range too.
Every thing I've read has been to get the idle right, then wideopen, then the mid range. If you changed the mains you need to start over with the mid range. The needle's are tapered, when you increase the main jet your also increasing the mid at the same time so you'd need to drop the needle to compensate for the increase.
 

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Discussion Starter · #7 ·
Re: Jetting problems. (continued)

Thanks everyone.

Does anyone know the part number of the GYTR needles? I was told by the local yammy dealership that I could only get them with the jet kit but if I found out the part number of the needles themselves I could probably get some ordered.
 

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Discussion Starter · #8 ·
Re: Jetting problems. (continued)

And so when you raise the clip you're dropping the needle down into the carb and thus leaning the mid-range right?
 

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Discussion Starter · #10 ·
Re: Jetting problems. (continued)

This thing is going to have TONS more power than it did before. When I bought it, it was jetted for 6k feet (I lived in Idaho), so it came with 122.5 and 125 mains... now it's jumped all the way to 160/165. This should be awesome. 8)
 

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Discussion Starter · #11 ·
Mike nailed it!!! I installed a 160/165 combo and now my rappy revs like a dream. Now it'll be ready for some fine tuning at the track next week! :wootwoot: :metal: :banana_hitit:
 
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