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Discussion Starter #1
Hi all, I've been riding my Vulcan for a while after I finished my ear shave. It runs just about as well as it did before I performed the mod. I was wondering about rejetting the carbs and wanted to know where you buy your jets and which ones I should replace. I have a stock exhaust on the bike and mostly did the mod just to get better access to the carbs. Do you recommend rejetting? Will there be any negatives to me leaving the jets alone? What are your thoughts?

Thank you. :smiley_th
 

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Try NicheCycleSupply.com. I was able to get 135 & 138 from them.
I think I got the '40' from Power-Barn.com

Just curious, which are filters did you use?
 

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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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Discussion Starter #4
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.
 

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Still running stock jets on mine.
 

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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.
 

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You didn’t rejet when you changed to pod filters? Just wondering I’ve got a cut in one of my air box boots and was thinking of doing the ear shave mod.


Sent from my iPhone using Tapatalk
 

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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.
 

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You didn’t rejet when you changed to pod filters? Just wondering I’ve got a cut in one of my air box boots and was thinking of doing the ear shave mod.


Sent from my iPhone using Tapatalk
Running Uni PK92 filters, stock jets, and stock exhaust for the past six years. It will pull past redline if I let it. 44mpg.
 

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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.
 

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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.
 
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