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Discussion Starter #1
I performed the ear shave procedure months ago but haven't truly taken it out riding...until recently. Long story short: I overjetted due to failure to read correctly and completely. My setup was: 142 main / 42 pilot, 2 needle shims per needle, K&N air filters, V&H Cruzers (de-goated) with Smartpartz quiet baffles and reed valve coasters in place. While throttle response was great, I encountered issues with high fuel consumption and bogging/hesitation often (gee, I wonder why).

After reading more, I came to the conclusion that I overdid it, big time. I then went with 138 main / 38 pilot and only 1 needle shim per needle. The other above options remained in place. Currently, I have carb #1 adjusted at 3.25 turns out and carb #2 at 3 turns out, which according to what I've read so far, is too much.

I went for a ride up Mount Lemmon in Tucson yesterday, and boy was the wind horrible. It seemed to be giving my carburetors forced induction with lots of hesitation, stumbling, followed by a burst of power (very bad). At it's highest point, we were at an elevation of over 8,000 ft. I had a hard time starting the bike when we left the restaurant near the summit. Returning to town (roughly 2,300 ft), the wind persisted and seemed to cause my carbs all kinds of problems. I think I'm back to square 2.

On a side note, the bike takes off like a greasy rocket with no problems, but does not do well with wind. I suppose that's the nature of the beast?

Has everyone that performed the ear shave with individual air filters experienced this issue with either high winds or fast highway speeds? How can I set the record straight?


-Catharsys
 

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I'm not earshaved, so don't take it from me, but it sounds like a carb vent issue. I read somewhere else with same issue, and I think carb vents were at fault. Make sure to put it in a location free of winds, like under the gas tank connected to the sender unit.
 

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FREEBIRDS MC CENTRAL NY
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I'm not earshaved, so don't take it from me, but it sounds like a carb vent issue. I read somewhere else with same issue, and I think carb vents were at fault. Make sure to put it in a location free of winds, like under the gas tank connected to the sender unit.
X2.I've never had problems in the wind.I'm earshaved with k&n pods,degoated with screaming eagle mufflers at about 1100 feet.140/40 with 2 shims
 

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Linkmeister Supreme
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I am not ear shaved and live at about 3500 ft.
I have read several times that you just need to put the vent hose out of the wind under the seat after an ear shave.

Other guys have said they had problems until they put a breather filter on the end of the hose. YMMV
 

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..have a vulcan good day!
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x4 !.....
 

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x5,but I will add, under the seat is not always a good place.. had my vent hose there at first, and it was horrible. tied it up under the tank (top side of frame rail) and no more issues
 

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FREEBIRDS MC CENTRAL NY
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I put mine right on the gas tank sender
 

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Discussion Starter #8
Yikes! As soon as I read the responses, I knew what I had done wrong. First, when I rejetted a second time to smaller sizes, I replaced the vent hoses with clear fuel line which is fine, but I ran the lines too far down. You know those two holes on the frame near where you install the rear bolt on the fuel tank? Yeah, I ran them through that area and they're nearly touching the rear cylinder coil pack (too long).

Secondly, since both side panels are off due to repainting, I'm guessing the wind was able to interfere directly with the vent lines thus causing a disturbance.

I'll take the sound advice and trim the vent lines and re-position under the tank.

Thanks for all the responses guys!
 

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FREEBIRDS MC CENTRAL NY
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Discussion Starter #12
I took my tank off to relocate my vent lines and found...something. The tank was pinning down one of the vent lines directly on top of the hose clamp screw on one of the coolant lines, making it crimped off. I cut the extended length from each vent line and 'gently' zip tied to the inside of the frame. Took the bike for a test ride and all was well until about 65mph, it began to bog and hesitate and act like it was running out of fuel.

Not sure if I yet again need to relocate the vent lines or if I have another issue.

Thanks for the replies (and the hilarious ones, too)
 

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Discussion Starter #13
I finally had time over the weekend to work on it and made several changes. I forgot about the plastic T so I shortened each line, hooked up the T and ran the one line closer in. It now can be ridden at any speed without bogging down or hesitating.

On other thoughts, I feel foolish that something as major as float bowl vent hose routing could easily be overlooked.
 

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Hey guys I did the ear shave jetted to 140 42 removed the goats belly but still stock exhaust. The vent tube is under tank on the sender. I had one shim on the needle but remove it today it runs fine up to anywhere between 3500 and 4000 rpm then just bogs out falls on its face. Any clue what I did wrong? Should I just go back to stock jets? Oh I have coasters and free flow petcock with carb vacuums plugged as well. Please any help would be great this is driving me nuts.
 

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FREEBIRDS MC CENTRAL NY
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How did it run before earshave?
 

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How did it run before earshave?
Yes. When did the bogging first happen?

Could be:

1) too lean

2) too rich

3) diaphragms leaking or not seated

4) weak fuel flow from petcock

5) carb air vent exposed to wind - Where is yours mounted?

6) air filter blocking carb port - What brand and type of air filters did you use? K&N and Uni are two that are known to work with these carbs.

7) float height

You could take a ride and run it up to where it bogs out, let it bog for as long as possible, then cut the ignition and coast to a stop. Check a plug on each cylinder ... Are they wet or dry? Black, tan, or white?


Have stock jets in mine, earshaved with stock exhaust.
 

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1986 VN750
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I've ran both 42/142 2 shims and 38/138 1 shim while earshaved/v&h exhaust and it honestly ran 'ok' either way. I settled on the middle, 40/140 w/ 1 shim.
 

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Yeah I just got some cheap filters on it going to try the k and n. It was running fine before. The vent hose is up under the tank on the sender nipple. The petcock is what I was worried about from the first cause it looks like one line has to go uphill a little going to try and mess with the lines and get the right air filters and see if that helps. Thanks for all the input will update when I have gotten a chance to play with it. This is an awesome site for info glad I found it!
 

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Hey guys,

Lot of useful info here.

Ive been having trouble getting my carbs to run right after ear shave as well.

Can yall share with us where you order your jets / needles etc? I'm having a hard time finding them online, there's just pre made kits and such.

I'm going to try removing the filter from my carb vent line and just routing the line to the sender as well.

Thanks.
 
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