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Jet size for aftermarket exhaust and ear shave

7K views 23 replies 9 participants last post by  Ceal 
#1 ·
For the ear shave, I have read that 142 is a good size. I am looking to buy the necessary parts to do the shave but I intend on putting on a loud aftermarket set of pipes and I am thinking I should go to a 145/8 main jet. What do you guys think? And how about the slow jet? 40? 42?

How does the ear shave and re-jet affect the reliability of the bike?
 
#2 ·
Depends on the altitude you're at. 142/42 jets are usually for sea-level and near sea-level riders. I doubt you have to go all the way up to a 145, but I'm no expert either.

What's the altitude where you ride?

As far as reliability, I don't think it's affected at all. The only thing that has been mentioned is a bit lower fuel efficiency but increased throttle response and power.
 
#4 · (Edited)
No adverse reliability. Runs better. Hardly use the choke and starts easier...not to mention having to hold on a lil tighter. I don't think you need 145/8's, overkill IMO. Are you running straights? If so maybe then I'd do the 5's but jets that big are used for racing. Also, do you ride highway a lot? Cuz these bikes are loud on HW anyhow because of the high rpm, so with louder pipes you're ears may burn off, lol. I'm not usually below 80 on the HW and I think I'd voluntarily split my skull open with a hatchet if I had to ride straight pipes for any length of time :drool: , just sayin'. Anyway, good luck. :smiley_th

Would be cool to have turn-outs on these tho wouldn't it? Then you could Blat around town p-in' off the neighbors along with the HD's and then turn 'em off when you hit the high road, lol :beerchug:
 
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#5 ·
me too

I finally got my bike running yesterday but my throttle seems to be dragging. My ears are shaved and my pipes are dual right side cruizers. I live in Oklahoma so I went by the bike parts store right by my house and it turns out they have jets for $3 so I planned on doing this to help bring some more power back into the guts. I personally was thinking of going the 142 and 40 route and grab some shims from radio shack. My cruising under 40 is fine but it takes to much throttle to get over that so I think a little fine tuning will get it all covered. the 142/40 combo is just what I was thinking but it sounds good for what all you have described too. Hell I want some opinions on that before I even do it haha
 
#6 ·
your bike is shaved with stock jets?
 
#7 ·
Correct. It came with the shave poorly done, but done. So I redid it cleaning everything up a bit and now I am going to replace my jets and adjust accordingly to see how that makes it feel.
 
#9 ·
You'll love it...
 
#8 ·
I typically ride around 1200-2500 feet, northern part of Georgia. Sometimes I go to TN where it is 6000+ feet. Sometimes to Florida where it is maybe 100 feet.

So...what jets would you suggest?
 
#10 ·
All of them! lol

I honestly only know what jets I'm supposed to use at near sea level.

People should probably do what I did and try to find someone at the same altitude you're at that has shaved the bike's ears and ask what jets work for them. Might take a while though, questions about jets don't usually get many responses as to which jet for which altitude.

Again, we SHOULD make a chart. But that requires everyone at different altitudes to chime in! Or to have someone knowledgeable enough about the topic.
 
#14 · (Edited)
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#15 ·
hmm... according to that chart, I should use a 132 jet.

Here's the thing about that chart though. It doesn't take into account an increase in airflow at the intake (which is what the ear shave gives the bike).
 
#19 ·
You are correct sir :). Very good observation but it is a reference.

Basically the ear shave recommendation is to go with 140's. That's most common and has given the most owners great results. So it's a good starting point. I would just use the chart to look at the recommended alteration and add that percentage to the 140. When I ordered my jets, I was asked about mods and altitude and they set me up...which happened to be 42/140 :smiley_th
 
#16 ·
132 is stock for the 750, unmodified intake; 135 was stock for the VN700. I'm running 40 pilots, 140 mains, no shims with Uni pod filters. Sea level to a bit over 3000' I've had no problems.
 
#23 ·
I ordered them from the pjmotorsports.com that Voipdoc recommended. It's in the link above. They're quick and gave good service.:beerchug:
 
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