94 Honda VLX 600 busting up at half throttle.

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WrenchLife
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94 Honda VLX 600 busting up at half throttle.

#1 Unread post by WrenchLife »

Ok guys. I love this bike but its driving me batty. when I got the bike the tank was full of kreem just globbed everywhere inside and rusted badly. I go all the old kreem out. Ran electrolysis on the tank for a week and finally got it all out before I used Red Kote in the tank. That worked AMAZINGLY. I went through the carbs and they where just horrible. Had to remove the choke cable due to it being damaged, but I made sure the plungers where secured inwardly seated. I've still not gotten the bike to go over 42 MPH and at half throttle it just starts busting up and looses all power. By this I mean it just drops out to barely running. Mixture screws are set to 1.5 turns out from bottom. I've meticulously inspected the vacuum diaphragms for any side of leakage, and since been through the carbs 3 more times just to make sure I havent missed anything. I'm at my wits end with this issue. Anyone have any insight or ideas?

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BRUMBEAR
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Re: 94 Honda VLX 600 busting up at half throttle.

#2 Unread post by BRUMBEAR »

I would just replace the carbs
there aint nothin like it

GS_in_CO
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Re: 94 Honda VLX 600 busting up at half throttle.

#3 Unread post by GS_in_CO »

Could it be possible that the ignition system is weak?
Spark cutting out at wide open throttle can be a symptom because spark doesn't jump as far in fuel/air mixture as in vacuum. (partial throttle) Excessively wide plug gap, wires with gaps in them, or fouled plugs could do this.

My old man, who has worked on cars for about 70 years says "If it isn't running right, check the ignition. If it still isn't running right, check it again because you missed something." (I think that applied to points-based systems)
Ron

Current: 1988 BMW R100GS (the 'numberplate' model)

Past: 1987 Yamaha XT350
1983 Honda CB900F
1980 Honda XL185S
1979 Suzuki GS425E

WrenchLife
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Re: 94 Honda VLX 600 busting up at half throttle.

#4 Unread post by WrenchLife »

I'm thinking its in the choke plungers. Aren't they supposed to have needles on the end of the plunger.?

GS_in_CO
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Re: 94 Honda VLX 600 busting up at half throttle.

#5 Unread post by GS_in_CO »

WrenchLife wrote:I'm thinking its in the choke plungers. Aren't they supposed to have needles on the end of the plunger.?
I think you need an exploded diagram of the carbs.

I'm not sure what you mean about choke plungers. Those might be the constant velocity slides controlled by a diaphragm and if so, yes, there probably should be needles on them because that controls the main mixture.
(at least that's the case on Bing carbs like on my BMW)
Bike carbs mostly use enrichener circuits rather than choke butterflies.
Ron

Current: 1988 BMW R100GS (the 'numberplate' model)

Past: 1987 Yamaha XT350
1983 Honda CB900F
1980 Honda XL185S
1979 Suzuki GS425E

WrenchLife
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Re: 94 Honda VLX 600 busting up at half throttle.

#6 Unread post by WrenchLife »

Soo......... needed a break from the dreaded carb issue.. I ripped the seat off and used the factory seat pan to make a lower profile seat, more like a bobber style.. And under the seat..... A fuel pump. That does not work... I feel so stupid sometimes. I'll update with results. This may be a gravity fed system by the end of the day

WrenchLife
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Re: 94 Honda VLX 600 busting up at half throttle.

#7 Unread post by WrenchLife »

Back to the drawing board. pump actually functions 100%. so Ripping the carbs back off for what seems to be the 1000th time, and going through them meticulously again

WrenchLife
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Re: 94 Honda VLX 600 busting up at half throttle.

#8 Unread post by WrenchLife »

Got both bowls off and one was bone dry.... Had a plunger hung up. I feel like such a goober

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