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Hey guys... New to these forums and new to owning a VTX 1300R. Traded in my 2005 Aero 750 for this baby, and I love it.

One problem though is that often when I barely push down on the throttle at low speeds the bike almost stalls -- and even sometimes sputters or backfires. I assume this means it is a bit lean from reading here. I also assume I could play with the A/F screw a little bit to get rid of this... but dont know where to find it on my 2007 1300R. Can anyone help me with this?

Is this something I shouldnt play with, being a complete novice and having only ~500 miles on the bike? I took it back to the dealer... they rode it and said it was fine. Figures...

Anyhow, I really appreciate the help if you can give me any?

Thanks!

Kyle
yes it is a bit lean, read the post by Scar on the 1300 page it is a sticky and has tons of info.
 

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I followed Scars advise, It took some time to come up with a Manual, I found mine on ebay, Now if I come up with a problem, I try to find the section that could help me the most, Knowing your Bike inside and out will take a few minutes, But it makes riding more fun...
 

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vtx 1300c carb adjustment

I just installed a Hypercharger and a set of Cobra slashdowns. My main jet was a 195 so I left it alone and adjusted the A/F screw 2 & 1/2 turns and I still get some popping and backfiring what do I do from here? Thanks Axeman
 

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pair valve clock off plates, gotta get rid of the fresh air injection for the smog.

If you have any hesitation on acell then you need to follow the scar carb tune post on the 1300 board.
 

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Quick hesitation in accelerating

The easiest way I can reporduce the problem is to be in fourth gear at about 30-35 mph. Hit the gas hard to speed up. It will initially begin accelerating just fine and then quickly hesitate after about two or three seconds. Feels almost like a misfire but can't be sure. After the very brief hesitation it keeps speeding up just fine. It runs fine all other times. I first noticed this going up hill and accelerating to keep speed constant. Changed the plugs since it's easy enough to do but no help. I was curious if the "too rich" carb could cause this. Air filter has about 5,000 miles on it.

Where you at in Ill.? I'm originally from the Quincy area. Take it easy.
 

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Hey Guys, Downloaded the Service Manual to find out where exactly the A/F screw is on the Carb. I could not find anything on Carb diagram that shows a A/F screw. Is it known as something else? Pilot Screw maybe? Im stumped.
 

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I could not find anything on Carb diagram that shows a A/F screw. Is it known as something else? Pilot Screw maybe? Im stumped.
The A/F screw or the pilot screw is the same thing. ;)

Biddy
 

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Hey Guys, Downloaded the Service Manual to find out where exactly the A/F screw is on the Carb. I could not find anything on Carb diagram that shows a A/F screw. Is it known as something else? Pilot Screw maybe? Im stumped.
FWIW here's an old school method of adjusting the A/F screw that has worked well for me. The idle mix is right when you blip the gas and the idle returns to the correct rpm. If it momentarily dips too low, then returns to the correct idle rpm (900-1000rpm) it's rich. If it's lean, the idle speed increases dramatically when you open the A/F screw. The 'idle drop' procedure in the shop manual is pretty close to accurate. Open the mix screw until no more increase in idle speed is apparent, then back in roughly 1/2 turn. With my current int/exh setup this method put me at 2-1/4 turns and runs it flawlessly.

Biddy
 

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Carb adjust questions

OK. Here is where I am at with adjusting the carb on my '05 1300C.

Symptoms:
Bike accelerates fine until around 3rd gear. Then it acts like it is struggling to get fuel.
At 3rd gear thru 5th in cruising speeds bike surges back and forth with power.
At cruising speed there is rattling in the exhaust.
At deceleration although I have the reed vavle blocking kit installed there is still backfire.

Equipment:
2005 Honda VTX 1300C
Vance & Hines Big Shots
BAK Kit


All of this was going on during a 3 day trip I was on. To me it seemed like it was running too lean so I kept adjusting the A/F screw out periodically at stops. Nothing I did made any improvement, so I thought maybe I was wrong and brought the screw back in to lean the mixture. I also did this because people told me they saw smoke coming from my exhaust and that it smelled rich.

After all this the bike continued to have power issues at cruise. In an act of desperation to save my trip and atleast make the ride enjoyable, I found that if I slightly engaged my choke all of the issues virtually went away. This leads me to believe that I was in fact running to lean and maybe I had just not brought the A/F screw out enough. At the time I stopped bringing the A/F screw out I was probably at around 4 1/2 turns.

Any suggestions here? I am wondering if maybe my petcock screen is blocked. I did have my tank painted a while back and the guy at the shop warned me that paint could come off around the gas opening and flake into the tank. Or maybe I need to further shim the needle as I have read about. Right now it only has one shim/washer. Maybe it needs two or three?? Not sure. Can someone explain how this affects the carb?

Thanks for any help!
 

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Your A/F screw ONLY affects 0-1/8 throttle position.
your needle position affects the rest of the throttle so add a shim to the needle and put the A/F back to around 2 1/2

OK. Here is where I am at with adjusting the carb on my '05 1300C.

Symptoms:
Bike accelerates fine until around 3rd gear. Then it acts like it is struggling to get fuel.
At 3rd gear thru 5th in cruising speeds bike surges back and forth with power.
At cruising speed there is rattling in the exhaust.
At deceleration although I have the reed vavle blocking kit installed there is still backfire.

Equipment:
2005 Honda VTX 1300C
Vance & Hines Big Shots
BAK Kit


All of this was going on during a 3 day trip I was on. To me it seemed like it was running too lean so I kept adjusting the A/F screw out periodically at stops. Nothing I did made any improvement, so I thought maybe I was wrong and brought the screw back in to lean the mixture. I also did this because people told me they saw smoke coming from my exhaust and that it smelled rich.

After all this the bike continued to have power issues at cruise. In an act of desperation to save my trip and atleast make the ride enjoyable, I found that if I slightly engaged my choke all of the issues virtually went away. This leads me to believe that I was in fact running to lean and maybe I had just not brought the A/F screw out enough. At the time I stopped bringing the A/F screw out I was probably at around 4 1/2 turns.

Any suggestions here? I am wondering if maybe my petcock screen is blocked. I did have my tank painted a while back and the guy at the shop warned me that paint could come off around the gas opening and flake into the tank. Or maybe I need to further shim the needle as I have read about. Right now it only has one shim/washer. Maybe it needs two or three?? Not sure. Can someone explain how this affects the carb?

Thanks for any help!
 

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Jersey Bounce
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Am I too lean??

I recently installed HOA slip on's and had the bike rejetted. Yesterday, I remove the chrome pipe shields and wrapped the pipes (only) with Therma tape. After a test ride, I'm getting alittle backfire during decelleration. Am I too lean?
 

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I'm beginning to believe you guys are conning me, and there is no such thing as an A/F screw. It's a conspiracy which includes the people who wrote the manual, putting the least helpful drawings I've ever seen as to where the sucker is. It's possible that the factory ran out of carbs, and decided to mess with the next buyer, and put fuel injection on mine. I already bought the tool from Glen's Garage, and I guess he's in on the conspiracy too.
 

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on this pic it is just above the #15

now if you put the bowl back on it would be at the back of the carb on the bottom looking from the filter side, now with the tool you will get to it from the key side and it is behind a hose.

 

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The guitar, not the fish!
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I don't have any picsw, but when you look at the bottom of the float bowl, you'll see a tube shaped thing molded into the carb bottom pointing down...The A/F screw is inside that tube....Can't see it unless you either rotate the carb up a little bit, or lay on the floor looking up at the carb bottom...Not a very convenient location at all...:banghead:
 

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was wondering where you got dwnload on service manual, I do need to get one one way or other, also was looking for af or pilot screw also to make ajustment , not sure where it is exactly on carb , saw pic that was sent to u but still? any help on this would be great. thanks
 

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thanks bowman, what kind of tool would I need for ajusting this ? not sure if ajusting will help ,she had a lot of carbon on plugs and needed choke for a long time when first starting , and was sluggish on excelleraiton so was thinking was running too rich. so I changed plugs and replaced air filter with [email protected] filter and start up is better , plugs dont seem as black but still slugish and some popping from exaust, do you think its lean now? carb was rejjeted by friend when installed big shots.?????
 

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thanks bowman, what kind of tool would I need for ajusting this ? not sure if ajusting will help ,she had a lot of carbon on plugs and needed choke for a long time when first starting , and was sluggish on excelleraiton so was thinking was running too rich. so I changed plugs and replaced air filter with [email protected] filter and start up is better , plugs dont seem as black but still slugish and some popping from exaust, do you think its lean now? carb was rejjeted by friend when installed big shots.?????
Well the friend that jetted the bike didn't need to with just pipes, odds are you are lean on the top end and the bottom end isn't adjusted properly.

you can use a blue electrical butt connector to turn the screw gotta push it on tight.

I would take all the way being careful not to loose the washer spring and o-ring then cut a slot in the screw head with a dremel to accept a stright blade screw driver.

put back togeather spring on the needle then washer and last the o-ring then screw it all the way in till lightly seated, now turn back out 2 full turns and you should be all set might need to make some small adjustments later on.
 
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