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post #1 of 22 (permalink) Old 06-25-2010, 08:04 PM Thread Starter
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post ear shave problem...

I got the ear shave done today going to a single air filter. The problem is the bike runs fine in the driveway, but taking off from idle to about 1/4 throttle it sputs and putts.... to the point where I have to flick open the throttle to get it to respond. Not an issue at speed, only when taking off or at low speed is there a problem.
I like the cleaner look with no visible ears or air box. And the popping on decel is completely gone now, also seems to have a bit more power in the mid to upper rpm levels.
So what could be the issue off throttle?
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post #2 of 22 (permalink) Old 06-25-2010, 08:16 PM
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Originally Posted by dariv View Post
I got the ear shave done today going to a single air filter. The problem is the bike runs fine in the driveway, but taking off from idle to about 1/4 throttle it sputs and putts.... to the point where I have to flick open the throttle to get it to respond. Not an issue at speed, only when taking off or at low speed is there a problem.
I like the cleaner look with no visible ears or air box. And the popping on decel is completely gone now, also seems to have a bit more power in the mid to upper rpm levels.
So what could be the issue off throttle?
Try turning in the pilot screws to 2 turns.


85 VN700 "Old Yella"

REBUILT ENGINE
CUSTOM PAINT
VANCE & HINES CRUZERS
EAR SHAVED AND RE-JETTED W/K&N'S
DUNLOP ELITE K591 FRONT & REAR
VOLTMETER
SYNTHETIC BRAKE FLUID
SYNTHETIC OIL & GEAR LUBE
PLEXISTAR 2 WINDSHIELD
SPLINES LUBED
ACCT'S GREASED W/TOC SPRINGS
COASTERD
LEATHER SADDLE BAGS
LEATHER TOOL AND ROLL BAG
PICKUP COILS GAPPED AT .018"
NGK CAP, WIRES, IRIDUMS
BARNETT FRICTION PLATES & SPRINGS
CUSTOM GRIPS, MIRRORS, LEVERS
ORIGINAL STATOR & R/R 14.5v
DEKA MF AGM ETX15L

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post #3 of 22 (permalink) Old 06-25-2010, 09:05 PM Thread Starter
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I'm at three turns right now....
BTW- I have #42 pilot jet
#145 mqin jet
1/4" shims under needles
All emissions removed, coastered, V&H Cruzers....
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post #4 of 22 (permalink) Old 06-25-2010, 09:54 PM
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three sounds a bit much... i am running the same set up at 2 1/4 turns, I started out at 2 1/2 turns out and had to screw them in 1/4 turn to correct the same problem you are having.
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post #5 of 22 (permalink) Old 06-26-2010, 02:48 PM Thread Starter
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Now at two turns out and running great! It's raining right now so I haven't taken her out for a proper ride......but seems to be ok now.
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post #6 of 22 (permalink) Old 06-26-2010, 09:20 PM Thread Starter
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Looks like I spoke too soon.......
The bike ran great until it warmed up, then the part throttle problem returned...worse than before. I am having a problem with the crankcase breather tube, looks like it might be collapsing on itself in one of the bends... I'll fix it in the AM, but could the blocked breather have anything to do with it?
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post #7 of 22 (permalink) Old 06-26-2010, 10:02 PM
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yes that could be a problem.
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post #8 of 22 (permalink) Old 06-27-2010, 02:22 PM Thread Starter
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ok....well definitely not the breather.
the bike runs great until it warms up, then begins to sputter at part throttle. idles fine and once you open the throttle past about 1/4 it runs OK.

I've tried a/f from 1/2 turn to 3 turns.....makes no difference on part throttle hesitation. I replaced the plugs with NGK iridiums and all the plugs I pulled were brown with the exception of the right rear plug....it was black.

also checked the voltage at the accesory outlet. it reads 11 volts at idle and 12 at around 2000... it maxes out around 13.5 @ 4000 rpm...
Don't think this is the problem, since the bike ran fine before the ear shave.....but who knows.

Last edited by dariv; 06-27-2010 at 04:25 PM. Reason: added info...
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post #9 of 22 (permalink) Old 06-27-2010, 10:53 PM Thread Starter
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My understanding is that the a/f screw only controls idle.
The pilot is used for part throttle, then the needle kicks in with more throttle, and finally the main jet. If so, could my problem be the #42 pilot jets?
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post #10 of 22 (permalink) Old 06-27-2010, 11:16 PM
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Quote:
Originally Posted by dariv View Post
My understanding is that the a/f screw only controls idle.
The pilot is used for part throttle, then the needle kicks in with more throttle, and finally the main jet. If so, could my problem be the #42 pilot jets?
The A/F mixture screw controls the pilot circuit, turning in decreases the the ammount of fuel from the pilot jet and turning out increases the the ammount of fuel.

It is a misconception that the mixture screw and pilot circuit are for idle only, Wrong!!

The pilot circuit works from idle to around 2200 rpm, at this point the pilot jet is at maximum flow and any additional fuel needed comes from the main jet.

The pilot jet is not your problem, it's either incorrect shims, diaphram not fully seated, or debris in a passage way.

What shims did you use and how many?


85 VN700 "Old Yella"

REBUILT ENGINE
CUSTOM PAINT
VANCE & HINES CRUZERS
EAR SHAVED AND RE-JETTED W/K&N'S
DUNLOP ELITE K591 FRONT & REAR
VOLTMETER
SYNTHETIC BRAKE FLUID
SYNTHETIC OIL & GEAR LUBE
PLEXISTAR 2 WINDSHIELD
SPLINES LUBED
ACCT'S GREASED W/TOC SPRINGS
COASTERD
LEATHER SADDLE BAGS
LEATHER TOOL AND ROLL BAG
PICKUP COILS GAPPED AT .018"
NGK CAP, WIRES, IRIDUMS
BARNETT FRICTION PLATES & SPRINGS
CUSTOM GRIPS, MIRRORS, LEVERS
ORIGINAL STATOR & R/R 14.5v
DEKA MF AGM ETX15L

Best Auto/Moto Insurance | Motorcycle Protection Today | FREE Trade-In Quote
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