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Thread: Rejetting after ear shave? Reply to Thread
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  Topic Review (Newest First)
06-09-2019 07:58 AM
Jason Pittenger ubertalldude I forgot about the coil mod. Interesting that you ended up with 38/135. I've heard that each bike is a little different. Mine HATED shims. Ran at idle and WOT but stumbled at cruise.

Even with the 40 pilots, it's still lean in specific circumstances. I don't need to go through my whole story again, as I have a 6 page thread on finding the right jets. 😉

I just don't understand how two bikes with the same setup could require different jets...but it is what it is.
06-08-2019 11:07 AM
ubertalldude You may do well with a slight rejet then. I'll tell my tale and eventual final tune:

Rejetted when I did the earshave with 142/42 and 2 needle shims. Ran like that for a year or so, but the bike was pig rich. I could smell gas when I cracked the throttle, hardly needed choke to cold start it. After I did the pickup coil modification, I found that it was really eating up that rich mix, but I wasn't a fan of the smell and (am pretty sure I had some erratic running issues)

I switched back to a stock pilot (38) with 1-size above stock main jet (135, stock is 132) and left my shims in place. With the coil mod and earshave, my bike starts with choke, doesn't smell pig rich, and responds perfectly to all rev ranges, throttle inputs, etc. Pulls strong through the whole rev range, doesn't pop on decel, and idles at a very stable 1100 rpm, hardly even have to fiddle with the idle when seasons change.

Way I reckon is this: stock pilot works at idle, that's limited not by intake/exhaust, but by the valve openings, no need to give it much more fuel there. Once the throttle comes on it's getting the needle lifted, the shims add a bit of additional fuel throughout the middle of the range where my pods let it breathe a bit more, and ultimately at WOT the main jet is giving it all it has, and I wanted just a bit more fuel there since the bigger pods will be providing more air.

Also worth noting that my stock pilots were unusable since they were so clogged, so even if I didn't rejet I still needed to replace the jets.

If you have punched baffles and an earshave, 135/38 or 138/38 might work well for you, and you can experiment with shims without removing the carbs, just gotta take the gas tank off to get the carb hats off. If you want more power in addition to this look up the coil pickup mod, I felt a big difference with that and the rejet.
06-07-2019 11:55 PM
BigA1991
Quote:
Originally Posted by Jason Pittenger View Post
I just got mine tuned in tonight, with 40/140. But I pulled my mufflers. Others with stock exhaust didn't need to rejet. If it runs fine, then leave it as is.


Guy I got mine off already cut all that out. And pulled baffles.


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06-07-2019 11:13 PM
Spockster
Quote:
Originally Posted by BigA1991 View Post
You didnít rejet when you changed to pod filters? Just wondering Iíve got a cut in one of my air box boots and was thinking of doing the ear shave mod.


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Running Uni PK92 filters, stock jets, and stock exhaust for the past six years. It will pull past redline if I let it. 44mpg.
06-07-2019 07:41 PM
Jason Pittenger I just got mine tuned in tonight, with 40/140. But I pulled my mufflers. Others with stock exhaust didn't need to rejet. If it runs fine, then leave it as is.
06-07-2019 04:18 PM
BigA1991 You didnít rejet when you changed to pod filters? Just wondering Iíve got a cut in one of my air box boots and was thinking of doing the ear shave mod.


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06-07-2019 03:28 PM
ubertalldude The backfiring is odd, is that only with the choke on?

Stripped out screw is no good, you might be able to get it out with vice grips and replace it. Ace Hardware/Fastenal will likely have an acceptable replacement (probably not a bad idea to replace with hex screws instead of the stock JIS screws. JIS screwdrivers are hard to find in the states, and using a Philips head screwdriver can strip them very quickly) Also worth replaceing the O--rings in the float bowls and the jet chambers, they were trash on mine and would have leaked badly had I reused them. Expensive, but worth it to replace.
06-07-2019 10:58 AM
Spockster Still running stock jets on mine.
06-07-2019 09:22 AM
Ty Gauthier The most concerning issue I have right now is after a ride I have a small leak of fuel coming out of the float chamber. One of my bowls has a stripped out screw that's in there good, I'm guessing that's what it's making it leak.

The bike also backfires a bit when it's warming up in the morning. Not loud, but kind of annoying.

I used Emgo pod filters.
06-07-2019 07:38 AM
ubertalldude If it runs right and the jets & carbs were clean, don't bother rejetting.

If you have running issues or upgrade your exhaust later, consider rejetting.
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