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excess fuel in the air box is a symtom of lean more often than not.

You need to tell which direction to make lean/rich with the A/F screw.
some carbs are the other way than ours.

also make a statement of clip positions on after market are the same as shimming up or down and a shim for half clip position.

might also add this link to help them understand the workings. http://www.factorypro.com/tech_tuning_procedures/tuning_carbtune,CV,lower_rpm_engines.html
 

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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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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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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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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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Here's my experience. I took mine and had it put on a dyno. They jetted my carb (back to factory) and showed me the printout. He explained that the bike is cold blooded, and I shouldn't be afraid to use the choke as long as I don't over-choke it or leave it on to long. .In an almost reassuring manner, he said "it's okay to use the choke". I suppose they put the choke on the bike for a reason.

So, I choke my bike, sometimes a seemingly long time. But I'll tell you this: it runs like a top, doesn't foul the plugs, and I just logged 36 mpg.

The choke is not the devil.
Read your owners manual on proper use of the choke then ask yourself why they state about half a minute use then fully off.

This is because they know it will foul the plugs fast

by the way it is page 40 and 41 in my owners manual.
 

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Sorry to all, I know this question has problem been asked a million times. It just stinks when it happens to your bike. I have a 2007 VTX-1300S and put Cobra Slash-down pipes on it. I purchased the Cobra Jet kit for it but have not installed it yet. I have ridden it several times and it has been backfiring when decelerating, other than that it rode fine.

However; yesterday I brought it for about a 120 mile ride. Towards the end of the ride the backfiring got worse then I couldn’t even accelerate. Every time I got on the throttle it would pop, backfire, and hesitate to the point I had to pull over.

Is this merely because I need to install the jet kit or is this problem something bigger? Is the jet kit easy to install or should I just bring it to the dealer?
You need to retighten the flange bolts, then you need to open the A/F screw about 1/2 turn then you need to get the pair valve block off plates on order and install them.

Jet kit is a waste of $$$ so return it if you can and if you change your intake then follow the scar carb write up it is a red sticky post on the 1300 board
 

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I know everyone has their problems but mine is quite similar and has snuck up just recently, running cobra speedster long pipes, Kury pro hyper charger w/jet kit (consisting of #65 pilot, #185 main, and 0.8 needle shim i believe those are the numbers) and recently it has been experienceing a engine surge whil in 5th gear and running around 60-65 mph. I have done no mods other thatn the afore mentioned, I have the block off plates for the pair mod but have not yet installed them andI have not adjusted on the A/F screw at all. Is it lean on top, do i need to adjust the A/F screw, will the pair mod help?
I bet there are over 100 post of the same problem, get that 65 pilot out of there get that 185 main out toss the needle in the trash along with everything else.

put the stock jets in get 2 (.020 shims) #4 washers set your A/F at 2 1/4 and you should be right in the ballpark
 

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there is only one size for the stock needle.

You can use the needle you have, granted it isn't as good.
clip position would be around the 4th from the blunt end and each bike is a little different in what it likes, so if you have a shim you can try 3, 3+shim, 4, 4+shim so you have 4 different settings you can work with.
stock main jet is the 195
stock pilot is the 55

Radio Shack Part # 64-3022
 

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Looking for some help. I put V&H cruizers on my 08 vtx 1300 C. I bought the jet kit but only installed the dynojet needle on groove #3 (did not install main jet). I put the A/F out to 2 1/2 turns. Bike seemed to idle fine but stalled out as soon as I throttled up in 1st gear. I tried 2 1/4 turns but not much better.
I posted on the other link you put the info in so check it out.
 

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Follow-up:
Charlie D said "Go to the 4th position and set the pilot A/F at 2 1/4 turns, make sure the vac
line is hooked to the fuel valve. you also want to make sure the tab on the slider and the top cap line up with
the cutout on the carb body. "

This worked! 4th ring and 2 1/4 turns. Thanks Charlie. Biggest culprit was misaligned tab (my bad). I feel my bike is about 90% there. Sounds great but I feel there is a little less power on low RPM's.
If I take my bike apart again this week should I go back and try ring 3?
open the A/F 1/4 turn more for the colder weather then when summer gets here just turn back in.
 

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I have the same exact prob. But mine is still completely stock. The only thing I have done is the clayton mod, but not the deep mod. When its cold weather I can let it warm up for a good 5 min and drive a few miles and still does it. Not so bad in the summer time. This is my first bike so I'm a noob.
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If you all would take the time to read the postings and then apply what they say you wouldn't be having the problems.
 

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You can only surf the web so much, on a blackberry and at work.
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Then what you do is send me or a few others a PM and ask for a walk through on how to get the bike to run like a champ.
 

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Well I adjusted my screw 1/2 turn, it made a difference, but it still has some hicups, I took the plugs out and they look ok...not white and not black..I'm colorblind so kinda hard for me to tell. But I'm still getting 47.75 mpg on a long rides, do I need to go a bit more with the screw?? Oh I have finally drilled into the first baffle at 12 and 6 o'clock positions in both pipes...sounds good. Thanks the Charlie D for the help before..was gonna pm you this but stupid blackberry want load that up.. Thanks Jeff
go another 1/4 turn and only run regular 87 octane gas
 

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Well, I did something today I never have. My buddy has a VTX 1300R, he has Cobra pipes with a half of a baffle (Yep he cut them in half) he has had probs with popping and stuff. So today I was going to check his A/F screw, by adviced from Master Charlie D, and his screw was only backed out 3/4 of a turn from bottom. WOW what a awesome dealership work! Then one of his VTX buds told him with his pipes ans K&N filter he needed to adjust the needle valve that what I call it. The long needle that goes up and down with the throttle. So I took that off and put the c clip 3rd slot from the bottom. He says it runs 100% better, he claims it runs better than when it was new.

Anyone ever heard bout adjusting that needle.
He has an after market jet kit in the carb and that needle with the clip positions is what we talk about lots on here, now if you add a shim washer and make it 3 1/2 on the position it should be even better along with that A/F screw set to around 2 1/2 open.
 

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One thing I do not understand about the A/F adjustment and maybe (probably) it has already been answered a gazillion times but.....if the A/F adjustment only affects the engine idle, how or why is it important for overall running performance of the engine at higher RPM, or is it at all ???
It doesn't play any role after you hit 1000 rpm now the pilot size does play a role all the way through the RPM band less and less as the RPM increases.

Many use the A/F to mask not having the needle set correct but it just isn't right.
 
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