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Discussion Starter #1
Need a little help here guys. I did some searching and there are a ton of these cutting out at wot threads. But theirs are without a delay. What makes mine different is it doesn't happen right away after w.o.t. and its not a sputtering like when you have to switch to reserve. It's almost an immediate power cutoff like hitting the kill switch. Takes abut 5 seconds to happen after throttle is fully open and ONLY fully open, not 3/4 , 7/8 or anything in between. When on the highway it could be 4th or 5th gear, at any speed. I'm assuming it happens in any gear but haven't tested the others cause like I said it takes a while for the power cut to happen and I don't wanna damage the engine. Had a rich running issue last year but fixed it. Cleaned the carb at that time(maybe not well enough on that main jet). Plugs look normal. Also added cobra dragster exhaust last year. Didn't notice if it happened after that. I was thinking its a main jet. Possibly (but slim chance the tps cause it's only in that position)? I Don't know if it's fuel delivery or electrical issue. I was going to do some preventative Maintenance to it so I'll take any suggestions. Other than that issue, bike is fine. Thanks for any help
 

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Replace vacuum lines.
Clean coil grounds and use dielectric grease also clean plug wires and some grease on them.

This is just simple things to start with.
 

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Discussion Starter #4
ok. Ill check all that. I replaced plug wires too last year and checked the coils when i was fixing the other issue. Thanks
 

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If after you let off the gas it catches up, then you are probably running out of fuel. Vacuum lines, plugged inlet filter, plugged tank filters.
 

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Discussion Starter #6 (Edited)
Fixed! I only replaced 2 vacuum lines going off the petcock (which were like new anyway). Also opened up the carb and everything looked clean (did it last year). Removed the jets and most of the internals and gave it a blast of cleaner since i was in there.
Float , diaphragm, etc looked good. Pair mod had already been done by previous owner so weren't too many lines.So, I don't know what it was but it's fixed.
Nevermind. Spoke too soon. I guess I didn't hold it open long enough the first time. Every thing mentioned, I checked.
 

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Discussion Starter #7
So, I had an issue the other day was messing with my bike out of boredom trying to get this problem fixed that i started the thread about. Checked over carb and put it back on. After that , it was not running good at all. It wouldnt run without choke. So yes, the plugs were black and I changed them and the oil (not fuel smell). Took carb off again thinking maybe a clogged pilot jet. Carb looked ok. There was some build up on the float bowl oring ( after 1 year , thats your ethanol!). Cleaned it up again and put a new gasket on. Put it together and it wasn't running good. So, I checked it over and saw the vacuum hose was not connected to the carb. Oops! Put it back on and the bike is like a new bike. It runs great . However, the original problem is still there. It still cuts out at w.o.t. I did notice it takes longer to do it though and for some reason the bike sounds very different to me. It does start a lot better. I changed the idle and the air/fuel ratio. i think I got it tuned perfectly. No hanging or anything with blip of the throttle. It's just that W.O.T problem. Any more ideas/suggestions on what to check. Ive checked everything mentioned. Vaccuum lines are new. Its only those 3 on the T right? The ones going to the carb and the petcock/tank. Pair mod was done. Petcock was pulled off and cleaned out last year. New filters (air and fuel (petcock screen). Fuel is getting to the carb. Maybe it's the main jet? Should I try a different one. i would hate to change anything since it's running so well. What about the float level measurement (I know its not adjustable) but I may have measured incorrectly. . The carb is getting fuel though. Not the usual symptoms of a bad one , but maybe a TPS? Im assuming Heffly is referring to the 2 screens , the one in the carb and the one in the tank? Im stumped! Thanks for any help!
 

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Have you tested the TPS???
It is a 5k or 6k potentiometer, ohm it or check the voltage. Ground on one end(Blue/Green), +5v on the other end(Yellow/Red), the variable connection(Red/Yellow) varies from 0 to +5 volts. It is probably easier to ohm it from the ICM connector.

Fuel flow--put vacuum on the petcock. I had a stream as large as the petcock fuel port ID pouring out.

On a low fuel level loosen the fuel cap, see if more air flow into the tank helps.
Vent clogged/restricted?? OR Blow air into the tank via the vent hose.

Run a wire to IGN coil (+) Black/White wire and connect it to a 12v led or bulb, ground the other lead. We want to see if voltage drops.

The ICM has two wires that have failed many times. Sometimes it goes completely open, sometimes intermittent.
Those two wires are the most forward wires on the ICM. Black wire or the Green wire one or the other breaks right at the weather seal on the ICM connector.
the wire insulation may neck down if strands have broken.

Did it ever run good since the August 2017 thread???
 

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Discussion Starter #9
Did it ever run good since the August 2017 thread???
It has always run great except for a a time where the carb was dirty. Never use the choke except when its really cold out. I even tried a different ICM that I have. I know its usually the wires and not the icm if there is a problem.
Im just wondering if I had this issue with the oem exhaust cause I know I must have had it wot with the oem exhaust . I just cant remember noticing it. I seemed to have noticed it around the time I changed exhausts to a cobra. IDk if thats coincidence or not. The airbox is stock though.

Hans, thanks for replying. You have helped me out before with some lighting that i was doing (diodes, etc). I will check/recheck this stuff and report back.
 

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Discussion Starter #10
Fixed!

Ok, think I found the problem!
I am having a problem with the bike running rich now all of a sudden though and the bike wasnt running well. This happened after playing with the carb trying to figure out the cutting out at w.o.t. problem thats been bugging me for months. I ordered a carb rebuild kit in case i need to get back in there. Plugs are black (carbon fouled , not wet and oily). I could smell the fuel. Oil doesnt smell though. I could swear my choke knob is getting slightly pulled open. I never have used the choke (or enricher whatever u want to call it). But, I was very very slightly tugging on it while bike was idling and it caused the rpms to change. Its like it is being pulled out of the carb slightly. It seems like there is no slack at all where the choke knob mounts on the bracket. I know there is a flat side on the threaded part of the knob and I do have it on there correctly.Everything on the other end seems fine . Although, slightly moving the carb around on its boot can tighten/loosen the slack also. My carb is mounted correctly too though. I know the boots mount with the tabs aligned. I think the bracket that holds the choke knob should have been inward towards the engine just a hair. I took a hammer and slightly banged on the bracket inwards towards the engine to get it just enough slack. I have read several threads where people have mentioned the choke being out. I think Im good on that now.
So...I said screw this, i want a f.i. bike. Then I calmed down and started diagnosing things again. Never got to the tps or any of that other stuff. Figured Id start at the tank and drain all the old gas ( just to rule bad gas out). Drained it , removed the petcock , and checked the fuel screen in the tank. Then I figured I might as well take the petcock apart and take a look and voila! The diaphragm was folded over (kinked up)! I must have read every cutting out at wide open throttle post from a google search and nothing mentioned the petcock diaphragm. The pic is kind of blurry but u can tell where it is not right. I tried folding it back over and getting it to its original form best i could. Maybe ill look for a used petcock on ebay since all i need is the diaphragm. I dont see it being sold seperately. Im assuming this was affecting the vacuum ? This is the only thing I changed. I took the bike on several test runs and held the throttle wide open probably ten times at least. One time I had it open for at least 10 -15 seconds. speedometer was buried. Didnt cut out once! Checked the plugs today and they were still dark but not as bad. The bike sounds fine where the a/f is set . There is no hanging or anything with a blip of the throttle. Its nice and smooth. Im all stock airbox and jets. Now I just have to get the rich condition licked!
 

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There is a cover kit with the diaphragm. About $30 at partzilla
5 COVER SET, PETCOCK 16953-KEA-000

The choke aka enricher is a spring loaded device that wants to close from spring pressure.
The flex cable is a slight bit long so 3/32" to 1/8" shows normally at the knob-rubber cover on the bracket.
If it does not have any slack then the enricher valve could be opened. SLACK is good.
If I said 1/8" valve lash between knob and cover maybe people would understand it better.
There is a friction adjuster(nut) under the rubber cover and you can set it loose or you can set it tight and manually close the enricher.
I use my enricher on every cold start.(excluding part of a summer 5 years ago)

Carb cleaning 101 by MR VTX many pix
https://www.vtxoa.com/forums/7-vtx-1300-riders-board/201519-carb-cleaning-101-a.html
 

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That's why I got rid of the $h!tty vacuum petcock a long time ago.
Went with a Pingle and never had an issue again.

http://www.pingelonline.com/prodcat/fuel-valves.asp

There is a tension adjustment on the choke knob area, under the rubber boot, or it could be corroded and sticking in the carb body.
 

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Discussion Starter #13
Yeah I know all about the tension adjustment. I didn't see that cover part. Wonder what the other one ending in 023 is. Maybe the same thing they just change part numbers sometimes.i think I did this to myself cause I inserted a pick in the vent hole to make sure it was clear and must have hit the diaphragm. Thanks guys. So the diaphragm not being fully seated caused a vacuum issue then
 

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I didn't see that cover part. Wonder what the other one ending in 023 is. Maybe the same thing they just change part numbers sometimes.
023 in reference to what?? I found it.. I will copy Honda parts numbering... Vendor change, or improvements, for last few digits

Babbitt's has it for $27

5COVER SET, PETCOCK
16953-KEA-000

5COVER SET, PETCOCK
16953-KEA-023

General parts have a part number divided into 3 sections,
The first string of digits (1234-XXX-XXX) indicates the Honda function and component number for this part.
The second string of digits (XXXXX-456-XXX) is the product code, also known as Parts Classification Number in hondaspeak. This is the number that indicates the product (motorcycle) where this particular part was first used. The product code is probably the most interesting portion of the part number when trying to determine interchangeability of Honda parts between various models.
The third string of digits (XXXXX-XXX-789) is the Classification Number. It is mostly used to indicate various suppliers or improvements for the same part. Also any potential color code is tacked at the end of the classification number as digits (letters).
 
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