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Discussion Starter #1
I just performed the ear shave on the '95. And BTW, that silly surge tank is a terrible clearance problem for getting the carbs out without pulling the engine (it is GONE now!). Anyhow, while re-assembling, I mistakenly plugged the vacuum breather that originally went to the surge tank breather. It ran so rich even at 1.5 turns out that just a couple of throttle pulls would flood it out, and you can forget starting (or even running) it if it's choked at all, even cold, with that line capped. The line I'm reffering to is the common between the carbs that has a factory T installed. Running that line to a small filter is must happen.
Let's just say I learned the hard way - DON'T cap that line if you're doing an earshave.
There wasn't enough time to re-sync and colortune... will do this evening. It already starts instantly when warmed up though... something it has never done before. I haven't driven it yet, so no idea how it will do under load.

I'm curious if anyone who has done the shave managed to get reasonable performance without changing the original jets? (Exhaust is original) Suggestions please?

Thanks in advance!
 

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Discussion Starter #3
Oh yes! Used to have to open the throttle about 1/2 way when hot starting. That is not to say the same won't be required after balancing the carbs and getting the mix set properly. Technically, I'd say it sounds like a rich mixture, but the screws are less than 2 turns out :) The colortune plug will tell the real story. I'll post some progress on how it goes this evening.

As for general warm starts, a good sealed battery (kept well charged) helps more than one would expect... well worth the $50. Also remember that if your bike still has the goatbelly on it, when you park it all that heat from the exhaust rises up around the battery compartment - and of course *bakes* the regulator if it's in the default location (on bottom of battery box). It is fairly well known on these forums that weak voltage will lead to all sorts of trouble such as poor charging, faulty ignition, etc. Plus at idle, you're basically running off battery power... the stator doesn't make solid amps until >2000 rpm.
 

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Nausea, What do you think of the colortune plug? Do you feel like your pilot jet/fuel screws are set optimally for throttle response, minimal vibration, and minimal decel popping when using the colortune plug?

What sized adaptor fits the VN750?

Thanks! Mark
 

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Discussion Starter #5
Mark... the Colortune plug is a great tool! You can watch the fire in the cylinder in realtime while adjusting. The instructions it ships with are quite detailed. Our bikes take a 12mm. See http://www.carbtune.com/colortune.html

The last time I used it on this bike was when I determined the carbs were filthy and not enriching on decel as they should. Sure enough, there was grit and other gunk plugging the tiny orifices and thus was not able to achieve a desired result on that run - although the mix was much closer and she definitely ran smoother abeit a bit rich on purpose. (hence the overhaul - the ear shave was afterthought of removal anger directed at the surge tank) :)

The vibration factor has alot to do with the carbs being in or out of sync... that sets the baseline for equal vacuum to which your mix can be set against. Might be wise to pull the carbs and verify that both throttle butterflys open/close at the same time as expected. Obviously, if the sync is out whack far enough, she'll shake and you'll feel one cylinder pull harder on takeoff.
I doubt that solely using a colortune will fix decel popping... there are other factors involved.
I'll try to find out who I bought this one from... I just remember it wasn't cheap :)
 

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Could you tell me exactly what you remove with an ear shave?

It seems to help things, but are their any cons?

How hard is it to do? Do you need any parts? Its cool you can start it much easier now. I'm planning on getting a sealed battery for sure.
 

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Discussion Starter #7
Well.. after the test ride(s)... it is safe to say that the stock jets are not gonna cut the mustard.

InsuredDisaster: the surge tank, the air filters, the hoses and vacuum diaphram that are attached to the heads and such are removed during a shave. Unless you actually like removing/disassembling carbs, leave it alone. As far as the shave actually 'helping' things, I don't know I'd say that - the carbs were gunked up before the shave and that was making it harder to start. More Seafoam may have cleaned them out... who knows? You'd need tools, lots of time, possibly a helper, a place to leave things disassembled... and patience.

On the bright side, now I'll get to pull the carbs out again which should be much easier now and re-jet/shim etc. Just isn't rich enough at higher rpms.
The sound? Normal at low rpm, LOUD at higher. Not sure who besides the rider can hear it, but there's no sound baffle between the carbs and the world.
 

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Discussion Starter #8
Mark, you asked about the Colortune : (not everyone stocks the MC version)
etoolcart.com - $66.27+shipping - Product Part #: 19-4171-100_AST
Motorcycle Colortune for 12mm spark plug 19-4171-100
 

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If you do an ear shave...you will HAVE to change the jets...i.e...go much richer.
Anytime you increase the amount of air, you need to increase the amount of fuel.
Even those that have tried keeping the ears on, and cutting bigger holes in them will find the mix will be too lean...and remember that the bike is set up fairly lean to start with.

KM
 

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My '06 is stock (airbox, filter, jetting) with about 1800 miles on it. I checked the plugs the other day and was surprised to see that they look brand new. The white insulator is still completely white.

My point is that this agrees with KM that the bikes are lean from the factory. There's probably a little performance to be gained and a small reduction in vibration by getting the jetting just right.
 

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Discussion Starter #12
Thanks, Knifemaker... I'm hoping 142/140 jets will be large enough... I've seen where some who have done the shave with non-stock pipes have gone into the 150's. I purchased the jets listed for the earshave in the Vulcan Verses... at least that is a starting point. I'm also pretty sure that I didn't get the carbs cleaned out as well as possible... think there is still grit in some of the orifices... using the colortune, I couldn't even get a rich mixture on accel/decel as expected on the back cylinder.
I'm hoping to redo the carbs this evening or tomorrow. Any suggestions anyone has would be great. And what if the new jets aren't big enough? Isn't there a way to re-drill them myself?
 

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Discussion Starter #13
Runs great with the new jets! Definitely has more grunt than before.
Totally cleaned the carbs, changed jets, shimmed needles and added fuel filters to prevent crud. Colortune shows the rear just a tiny bit richer than front - as well it should (142 vs 140). She runs as good if not better than my '05 :)
 

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Discussion Starter #14
Update: Ok, it doesn't run as good as I thought :)
Puttering around, hard accel, etc is not a problem. Maintaining a constant speed that requires more than 3k rpm IS a problem. I can feel one cylinder cutting out - like it isn't getting enough fuel. Accel again and it will pull, but back to steady speed and it misses.
Is it the shims under the needle that affect this (currently 2 on both)? Or is this strickly a jetting issue?
Thanks
 

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Discussion Starter #15
Much better now! (swapped jets) The larger jet needs to be on the front carb. Logical reason: the rear runs a tad warmer and should be a bit leaner, conversely the front is cooler, etc.
I do believe 142/140 jets are large enough... ran around in 1st and 2nd at 7000 rpm, cool and warm without any hiccups... there is enough gas flowing :)
The needle positions are close with 2 washers each, but need another run when cooled off to really tell. I still think it bogs a bit in the mid-rpms but not sure yet if it is rich or lean.
After setting needles comes the float levels - apparently they're not easy to adjust. I think at least one float was off when I got the bike as it has never pulled well under load under 2500 rpm - tends to vibrate in the that range and feels unbalanced.
Has anyone done the float adjustment procedure and is if so, do you have any tips?
 

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You did not mention if you went with a larger pilot jet. This is reccomended.And if memory serves me correctly...many have reported that they placed shims ON TOP OF the needle ..instead up under..not sure why but this is what I have read. You should also turn out the airscrew some.
Perhaps someone that remembers the part about shimming the needle will give a better discription.

KM
 

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Here...answered my own question on this (From Franks Earshave File) :

Here's some valuable information that I have collected regarding the Ear Shave.
This should get you started, but may require some more research.
Please note that I am not a mechanic. This is information only. If you're
unsure, have a pro do it. Feel free to email me or post any q's.

Check out Jason's Ear Shave: http://photos.yahoo.com/jaster131/

Check out Frank's Ear Shave: http://photos.yahoo.com/fcb64

Thanks to Jason Spivy for posting the parts list.

Ron Ayers:
1 x 14-20900 EMGO crank case filters* = $10.63
(this one mounts on the left side and connects to the crankcase
or you can order one more for the right side, connects to the
breather on the carb float bowl assebly)
Shipping = about $8.00 from California
*There has been problems with the adhesive on these filters,
most of us who have them used a stronger silicone or epoxy.

Auto Zone
1 x Spectre 3995 Breather Filter $9.00
(this one is used for the breather on the carb float bowl and
can be placed underneath & behind the seat)

Sudco:
2 x 019-812 40-Idle jet = $8.90
1 x 019-194 140-Main jet = $4.45 (2-140's seems to work for most)
1 x 019-195 142-Main jet = $4.45 (optional)
1 x 009-396 0.126" Shim 12 pack = $4.00
Shipping = about $8.75

Auto Zone (may have to special order)
2 x K&N RC-2340 = $71.82 (not including local tax)
-or-
AJ USA (www.ajusa.com) 1-800-877-1911
2 x K&N RC-2340 = $58.70 (includes "FREE" shipping!!)

1 x 1/4" rubber vacuum cap $1.59 (Autozone comes in pkg of 4)
(Used on right side of carb vacuum fitting)

Small cable tie (for the vacuum cap)

True Value: (optional)
2 x 20mm chrome bolts = $6.38
2 x chrome washers = $1.78
(non-chrome bolts and washers about $ .75)

Total = about $135.00

In case I made a typo, verify parts numbers before ordering.

The chrome bolts and washers were used to mount the crank case filters
(stock bolts were too short). One filter was used for the crank case
and the other for the carb breather hose. There are cheaper filters
than K&N but that is a personal preference.

You'll also need a new breather hose which can be bought at any auto
store. I used some hoses laying around here but it looks like you need
the hose, 45 elbow, and 90 elbow.
------------------------------------------------------

To answer several questions in one post:

Q: Why do you add shims?
A: After the ear shave, the needles need to be shorter.
As far as I can tell, no one makes a shorter needle for these carbs.
You may have read some other members posts about Sherm's rebuild
kit that includes replacement needles. I used the stock needles.
The only way to shorten the stock needles are to add shims
(obviously doesn't shorten it but raises it up a little).

Q: How many shims did you use on each needle?
A: I put two under each needle and that seems to work fine.
Two shims seems to be the standard that works for most people.

<This is assuming that you are using the original stock needles.>

The following is part of a discussion regarding the stock
needles -vs- the needles that are supplied with The Factory Pro
Jet Kit from Sherm's:
--------------------------------------------------------

Just to clarify -- I used 4 shims ON "TOP OF" each
needle, not under. -Pick
-------------------------------------------------------------

The shims go "UNDER" the head of the needle (like the head of a nail).

If someone said that they put a washer under a nail, it would most
likely be understood that the nail went "through" the washer, not that
the point of the nail was on top of the washer.

The needle is tapered, and with more air flow from the ear shave, more
fuel is needed to maintain the correct fuel to air mixture, so raising
the needle opens more area around the needle to flow more fuel.
I removed each needle, slid two spacers on, then put the needles back
in. This puts the spacers on the top end on the needle but not on top
of the needle. ??? I'm confused. What does putting spacers on top of
the needle do?-doowriter123
---------------------------------------------------------------

OK, I don't claim to know the whys and wherefores, but I got the ear shave
kit from Sherm's before they went out of business. I got a selection of
jets, shims, and new needles with the kit. I used 40 pilots and 140 mains,
with the clip in the 3rd position on the new needles. IIRC, that was in the
middle slot. I did not use any shims. The bike ran fine while
accelerating, but when I let off the throttle, it would stumble badly --
sort of like it was running out of gas or something (maybe it was
flooding?). I popped the tops off of the carbs and put 4 shims on top of
each needle, and the stumbling disappeared. The bike ran great all the
time, throughout the rpm range, accelerating or decelerating. I don't know
why this worked for me. It didn't make any sense to me either. I thought
the shims would have to go under the needles. I can only guess that putting
the shims on top causes more pressure to be applied downward, keeping the
needles from "floating" as much, or something like that. -Pick
----------------------------------------------------------------

Sooooo.... You didn't use the original needles. You had needles that
used clips that came with Sherms kit. The clip position limits the maximum
down limit of the needle. This explains the 3rd clip position.

If the clip on the needle is enough smaller than the vacuum slide
spring seat, the needle could possibly be able to wiggle around and
up and down, so putting shims on top could hold the needles down
where they should be.

The needles and clips are a more expensive way to get the result,
but they may have been chosen because of their profile. -doowriter123
------------------------------------------------------------------

That sounds plausible to me. The new needles came with the Factory Pro jet
kit, so I thought I may as well use them. If I had stayed with the stock
needles, I would most likely have used a different configuration to get it
to run right. -Pick
------------------------------------------------------------------

After the ear shave, the needles need to be shorter.
As far as I can tell, no one makes a shorter needle for these carbs.
The only way to shorten the needle is to add shims
(obviously doesn't shorten it but raises it up a little).

BOTTOM LINE-
Use the stock needle, and two shims "UNDER" each needle. -Frank Braun
---------------------------------------------------------------------

Q: My new jets seem shorter than the stock jets, is that okay?
A: The jets that come with the PRO Jet Kit are the same length
as the stock jets. The jets from Sudco seem to be shorter but
have the same effect. So length does not seem to be an issue.

Q: you mention bolts to mount the crank case & breather filters. Where
did you mount these?
A: I mounted them at the top bolt hole from the ears. (Some have
mounted to the bottom bolt hole) The old bolts
were too short so they had to be replaced.

Q: Whats the vacuum cap for?
A: The carbs have two vacuum connectors. One goes to the gas tank
petcock and the other one used to go to the surge tank. I decided to
plug the vacuum on the right side of the bike and secure it with the cable
tie. The engine seemed to idle better. Some people buy a small filter
and connect it under the seat. It's optional.

Q: did you take carbs out or do the needle & jet work with them in place?
A: I installed the shims with the carbs in place. I did everything I
could to install the jets without removing the carbs but couldn't do
it. Removing the carbs was easier than I expected. Plus it gave me a
chance to inspect the diaphrams and the connections.

Q: what is wrong with the ears ? why remove them ?
A: There's nothing wrong with them*. Some want to increase air flow in
order to increase power (and decrease fuel economy*). Others want a
cleaner, less cluttered appearance. I had one ear busted and needed to
replace it. Also, it seems that every time I did work on the bike, I
was hitting the ears with my elbow, head, etc. I don't mind the look of
the ears, but I do enjoy having less stuff in my way.

*Keep in mind that the ear shave may be illegal in some states due to the emmissions.
Save all the old parts just in case the laws change.
 

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Discussion Starter #18
Thanks, Knifemaker! Yes, I did change the pilots to 40 and there are two shims under the needles currently. I need to check the plugs again and see how they look. I'm probably going to tear into it again tonight and make sure the floats are properly set... I still think one is way off. Mid-range is so hard to tell... I think it is off too, but I really can't tell much difference between when it is hot or cold (and the docs claim that means it is right!). See http://www.vroc.org/archive/2004/msg171206.html and/or http://factorypro.com/tech/carbtune,CV,lower_rpm_engines.html

BTW, Knifemaker, aren't you in the DFW area? I like what I've seen of your handywork :)
 

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Discussion Starter #20
We're not too far above sea level here in Dallas. The common vacuum port between the carbs is tucked away with a breather filter on it. Oh yeah, I already made the mistake of capping that line - what odd results too!
Pulled the plugs last night and they were whitish... so it is running lean (as I suspected). Also confirms that it was lean surging I felt and not an overly rich condition. I won't have time to poke at it again until tomorrow night.
You know, those carbs have been off and apart at least twice and I didn't closely inspect the floats. One float is either way off spec, sticking or the valve seat is goobered. Let that be a lesson to us all - read ahead and do it right the 1st time! :)
 
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