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Sking1973
Posted on Wednesday, August 01, 2007 - 08:24 am:   Edit Post Delete Post View Post/Check IP Print Post    Move Post (Custodian/Admin Only)

Gearheaderiko: "Jets first, then the needle shims."

Does the needle HAVE to be shimmed though? If I don't am I going to do damage to the bike or am I just not going to get the full potential from my exhaust upgrade? Like I stated before, I found a couple of sites that just change out the jets and leave the needle alone when installing an aftermarket exhaust. I'm sure I could figure out the needle shimming (I do have a service manual) but I just don't want to tear the whole carb apart. Call me lazy! : )
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Gearheaderiko
Posted on Wednesday, August 01, 2007 - 09:39 am:   Edit Post Delete Post View Post/Check IP Print Post    Move Post (Custodian/Admin Only)

No, you dont have to do the needle shim and you wont do damage to the bike if you dont. Its actually easier than changing jets though.
I havent done the needle shim (but I've pulled needles).

The thing to remember is that these changes are guidelines and your individual carb tuning may be different according to where you live, riding style and mods. The ideal is to do whats necessary for your maximum performance.
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Sking1973
Posted on Wednesday, August 01, 2007 - 09:43 am:   Edit Post Delete Post View Post/Check IP Print Post    Move Post (Custodian/Admin Only)

Thanks Gearheaderiko for ALL the advise. Well, thanks to everybody actually! This forum has been a godsend.
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Ezblast
Posted on Wednesday, August 01, 2007 - 01:43 pm:   Edit Post Delete Post View Post/Check IP Print Post    Move Post (Custodian/Admin Only)

There is a noticable difference though between shimmed and unshimmed - I'd do it, its worth it.
GT - JBOTDS! EZ
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Xgecko
Posted on Wednesday, August 01, 2007 - 04:47 pm:   Edit Post Delete Post View Post/Check IP Print Post    Move Post (Custodian/Admin Only)

especially considering the cost and labor involved
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Buuueller
Posted on Wednesday, August 01, 2007 - 05:23 pm:   Edit Post Delete Post View Post/Check IP Print Post    Move Post (Custodian/Admin Only)

Not to be too redundant but where do the shims go. I understand the needle is attached to the float so when the bowl fills completely with gas the float rises, and acting as a teeder todder it forces the needle to seat on the jet preventing gas from over filling the bowl. What am I missing? Forgive me but Im much more experienced with automobile carbs (although Im sure theres not much difference) and I just dont want to tear it down before knowing for sure. Id hate to miss valuable ride time.
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Joey
Posted on Wednesday, August 01, 2007 - 06:18 pm:   Edit Post Delete Post View Post/Check IP Print Post    Move Post (Custodian/Admin Only)

That's a different needle. Pull open your slide and you'll see the needle behind it. As the slide goes up, the needle comes out, leaving more room for fuel to enter the carburetor.

Pull the top of the carburetor off, and you'll have access to the needle after you pull out the rubber part. The needle points down, and the base of the needle rests inside. The shims lift the needle up from its hole just a little bit.

I had a flat spot in my throttle until I shimmed!
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Buuueller
Posted on Wednesday, August 01, 2007 - 06:48 pm:   Edit Post Delete Post View Post/Check IP Print Post    Move Post (Custodian/Admin Only)

Wait...my gears are turning, would the shims be to allow the float to raise higher before the needle comes in contact with the jet? That would make sense if the jet is allowing faster fuel flow out of it, it would stand to reason that the bowl would empty faster. If this is the case the shims would go between the float and the top of the needle?
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Buuueller
Posted on Wednesday, August 01, 2007 - 06:52 pm:   Edit Post Delete Post View Post/Check IP Print Post    Move Post (Custodian/Admin Only)

Ooops, sorry Joey, I didnt see your reply. I guess I'll just take her off and do it. I aint scurd.

Thanks for everyones help.
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Ezblast
Posted on Wednesday, August 01, 2007 - 10:10 pm:   Edit Post Delete Post View Post/Check IP Print Post    Move Post (Custodian/Admin Only)










GT - JBOTDS! EZ
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Gearheaderiko
Posted on Wednesday, August 01, 2007 - 11:23 pm:   Edit Post Delete Post View Post/Check IP Print Post    Move Post (Custodian/Admin Only)

Ez-you da man!

The carb doesnt have to come off to change jets or shim the needle. Shimming the needle will require removing the tank cover though (or loosen the intake clamp and spin the carb).
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Buuueller
Posted on Thursday, August 02, 2007 - 05:02 pm:   Edit Post Delete Post View Post/Check IP Print Post    Move Post (Custodian/Admin Only)

You were about 2 hrs too late with those diagrams EZ..but thanks anyway. I saw a diagram on the link thats at the begining of the carb section of the site.

I got the jets and the shims in, but ran out of sunlight (cant afford a garage). It was very easy once I got it opened up.

My only mistake was drilling out the mixture screw too far. I accidently cut the grove off the top of the screw so now I cant adjust it.

Hey it was late....
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Buuueller
Posted on Thursday, August 02, 2007 - 06:07 pm:   Edit Post Delete Post View Post/Check IP Print Post    Move Post (Custodian/Admin Only)

OK, heres the verdict. I just got her put back together and tested. (45 slow and 175 main jets)

First, I may be nuts but when I first started her, it sounded different..good but a tad different.

Next I noticed it wouldnt idle, but ran fine otherwise. It never got better either. Im sure if I had a mixture screw... I could smooth it out (see above post).

It also mildly but often pops in the exhaust during deceleration. Backfiring in the carb was a big player too. It backfired so hard one time it blew the carb out of the boot. Thank goodness I had my leatherman with me.

As far as performance improvements Id say it has a more broad torque curve. Taking care of that mid range "flat spot" everyone talks about.

Taking into consideration that I only have a K&N filter and stock exhaust, Im sure Ill feel more of an improvement once my pipe gets here (been on order for 2 weeks).

It looks like Im going to have to take the carb back off to "easy out" the bad mixture screw.
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Joey
Posted on Thursday, August 02, 2007 - 06:40 pm:   Edit Post Delete Post View Post/Check IP Print Post    Move Post (Custodian/Admin Only)

Sounds like when you drilled it, you might have turned the screw in a little, making the idle entirely too lean. Get yourself an EZ-Out to get the screw out. If there's enough left, you can probably make something of a slot on the screw to make it adjustable.
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Gearheaderiko
Posted on Thursday, August 02, 2007 - 07:52 pm:   Edit Post Delete Post View Post/Check IP Print Post    Move Post (Custodian/Admin Only)

Concur!
If you've ran the drill into the screw so hard as to strip the head, then you've probably run the screw in tight (bad). I would carefully try to remove it with a good phillips or flat blade screwdriver first.
Once out it can be replaced with an 'EZ mixture' screw. It fits any HD CV carb (Sportster/Big Twin), most HD aftermarket retailers carry it, about $22 and allows you to adjust the mixture via a thumb screw. (probably easier to find than a stock carb screw).
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Sking1973
Posted on Thursday, August 02, 2007 - 08:32 pm:   Edit Post Delete Post View Post/Check IP Print Post    Move Post (Custodian/Admin Only)

OK new question, what if you run a 175 main and a 40 slow jet? I couldn't get the slow jet to budge and I'm afraid to torque on it too hard for fear of breaking something.
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Buuueller
Posted on Thursday, August 02, 2007 - 11:15 pm:   Edit Post Delete Post View Post/Check IP Print Post    Move Post (Custodian/Admin Only)

I wouldnt worry about it too much, although its brass it should hold up to a good screw driver.

Wiggle the screw driver a bit to make sure its all the way in the slot of the jet, and that it is contacting both sides of the slot (since there is a hole in the middle), press down as you turn and put a good LEFT turn on it. It will come loose.

Mine was pretty tight too. For me,I think it was easier to get good torque on it since the carb was off the bike.

Too lean? I was thinking too rich because of the popping, like from extra fuel. But I admit I didnt think of the screw getting turned by the bit. Yall are some fart smellers.
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Ezblast
Posted on Friday, August 03, 2007 - 12:04 pm:   Edit Post Delete Post View Post/Check IP Print Post    Move Post (Custodian/Admin Only)

Too lean!
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Sking1973
Posted on Saturday, August 04, 2007 - 02:24 pm:   Edit Post Delete Post View Post/Check IP Print Post    Move Post (Custodian/Admin Only)

I FINALLY got the 45 slow jet in my carb. I had to grind a screw driver down to fit the slot perfectly, but the old one came right out. While I had the bowl off I changed out the screws that hold it on to allen head screws instead of the phillips head. I'm relieved that that project it over.
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Myrtleblast
Posted on Saturday, March 22, 2008 - 07:49 pm:   Edit Post Delete Post View Post/Check IP Print Post    Move Post (Custodian/Admin Only)

OK.I need you guys to clarify and make sure I'm going to do this right. First off, I installed a VH exhaust and will be adding a velocity stack. I bought a 45 jet and a 175 jet. Will these give me sufficient air mixture?

next, I will want to shim the needle, right?
I'm going to explain how I think this will be done and you guys please let me know if it sounds right. keep in mind I am a complete novice when it comes to this kind of stuff, but feel pretty confident it can be figured out by a noob with the proper guidance.

*First things first. remove the seat, tank cover and airbox cover.

*next, remove the float, which is a black piece of metal or plastic located on the bottom of the carb.?

* once the float is off I will see the two jets in the middle. I remove the two jets, and replace them with the correct replacement parts. (when I replace them, do I screw the new jets in all the way?) underneath these and kind of seperate from the rest of the carb will be a nub-thingy.

*under this nub is the idle fuel mixture screw? I will CAREFULLY drill out the nub to get at the screw underneath. Once I have exposed the idle fuel mixture screw I start the bike? With the bike is running I turn the screw to the right counting revolutions until it starts sputtering. then I count revolutions as I spin it to the left. Once it starts sputtering I find the difference in revolutions and turn that many times back toward the right.?

*If this is correct so far, outstanding!! feel free to correct me or warn me of any troublesome areas.

Next is the shimming of the needle. this part confuses me. since my carb will be exposed, I may as well do this part of it. I read that shimming gives the bike a bit more pep in the mid range.

I have no idea of where the needle is or how to get to it. Please, anyone familiar with this procedure post a step by step in layman's terms for me to do this. Also pics would be super helpful!!! I've read about all I can on this topic. sorry if this seems redundant or has already been explained to death, but I can't find anymore info than what I've already explained.

Thanks in advance and Happy Easter!!!

(Update): I've been looking a little closer at the diagram above and think I have an idea as to how the shimming works.

*On the top of the carb is another black piece of plastic or metal. This needs to be removed.

*once removed, a spring will come out> set this aside.

*there will be some sort of diaphragm with something attached to it.

*I will GENTLY remove this diaphragm and an apparatus with the pin will come with it. Take the needle out and put a washer on it? if so, what size washer? i think it needs to be shimmed .05 right?

* once the washer is on the needle just re-assemble everything in reverse order?


I hope this is correct. My bike has been down a week due to a snapped clutch cable and it's killing me!!! will be busy tomorrow for easter, but on monday I will be tackling the cable, re-jetting and shimming. I hope to have a solid base of knowledge before I start this project so post as soon as possible please!!! thanks again!!!

(Message edited by myrtleblast on March 22, 2008)
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Gearheaderiko
Posted on Saturday, March 22, 2008 - 08:16 pm:   Edit Post Delete Post View Post/Check IP Print Post    Move Post (Custodian/Admin Only)

STOP! The carb is delicate. Go slow.

The float bowl is silver metal. Use a new or good screwdriver on the jets and screws. Screw the new jets in tight (within reason-its unlikely they'll vibrate loose).
DONT drill out the plug with the float bowl off. Again, go slow.

When doing the needle only remove the spring and plastic 'spider' piece, dont remove the diaphram. The needle can be pulled out with needle nose pliers..05 is about 2 washers.

45/175 & 2 shims should be okay along with 2 1/2 turns out. Remember, this is ballpark. Your results may vary especially if running a stack and we really couldnt possibly know how well your bike is running.

You dont actually have to take the tank and cover off, but being new I would advise it.

(Message edited by gearheaderiko on March 22, 2008)
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Buellistic
Posted on Saturday, March 22, 2008 - 10:32 pm:   Edit Post Delete Post View Post/Check IP Print Post    Move Post (Custodian/Admin Only)

ball park is correct, maybe ??? (;^)
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Jerzydevil
Posted on Saturday, March 22, 2008 - 11:09 pm:   Edit Post Delete Post View Post/Check IP Print Post    Move Post (Custodian/Admin Only)

Buellistic, your color commentary is getting very annoying. Everyone knows YOUR "opinions" on everything. Not everyone has cash falling out of their pockets to dyno every change they make or to pull the whole bike apart to measure chain tension to find the tight spot in the primary. You obviously do. So please either post all your dyno runs and help everyone, or keep your comments to yourself. For most of us, ball park is close enough.
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Ezblast
Posted on Sunday, March 23, 2008 - 12:09 am:   Edit Post Delete Post View Post/Check IP Print Post    Move Post (Custodian/Admin Only)

If your running the now common gas-ahol that is mandated at most stations, I would suggest a 48 primary/180 main and 2 3/4 turns out on the air screw as well as the shimming. If your going with the stack - use the stock number for the filter by Outerwears that I have listed in my profile currently - flows twice as much as the old style I ran and is a much smoother ride for it.

Oh - don't touch the float - its not necessary - saying that for prosperity since you know that by now.
EZ
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Myrtleblast
Posted on Sunday, March 23, 2008 - 02:34 am:   Edit Post Delete Post View Post/Check IP Print Post    Move Post (Custodian/Admin Only)

thanks guys, but EZ, what do you mean don't touch the float? I thought you had to remove the panel thing from the bottom of the carb to get at the jets? am i missing something?
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Buellistic
Posted on Sunday, March 23, 2008 - 09:44 am:   Edit Post Delete Post View Post/Check IP Print Post    Move Post (Custodian/Admin Only)

maybe he does not know how to adjust it, "YET" ???
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Styxnpicks
Posted on Sunday, March 23, 2008 - 12:00 pm:   Edit Post Delete Post View Post/Check IP Print Post    Move Post (Custodian/Admin Only)

is it usuall to have the "dry" side of the carb soaked in fuel after a ride?
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Gearheaderiko
Posted on Sunday, March 23, 2008 - 12:06 pm:   Edit Post Delete Post View Post/Check IP Print Post    Move Post (Custodian/Admin Only)

No! If its soaked in fuel the source should be fairly easy to find. Turn of the fuel and dry the carb off, then turn the fuel back on. My guess would be a bad fuel line or loose carb screws.
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Styxnpicks
Posted on Sunday, March 23, 2008 - 01:06 pm:   Edit Post Delete Post View Post/Check IP Print Post    Move Post (Custodian/Admin Only)

I'm not talking about fuell on the outside of the carb lol, but like the filter side of the intake tract seems to get soaked pretty good
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Buellistic
Posted on Sunday, March 23, 2008 - 02:50 pm:   Edit Post Delete Post View Post/Check IP Print Post    Move Post (Custodian/Admin Only)

been wondering about the same thing too ???

will it go away if you get rid of the air box and install a RACE FILTER set up ???
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