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Mike_lee
Posted on Tuesday, August 28, 2018 - 08:28 pm:   Edit Post Delete Post View Post/Check IP Print Post    Move Post (Custodian/Admin Only) Ban Poster IP (Custodian/Admin only)

Cannot find where it was stated 45pilot, 190main and washers on the needle. Was that with the e-clip in the 3rd position?
The bike just doesnt pull like it should between 1/4 and 3/4 throttle. Want to remove the xl needle and replace it with the oem that came out originally.

(Message edited by mike lee on August 29, 2018)
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Upthemaiden
Posted on Wednesday, August 29, 2018 - 07:49 am:   Edit Post Delete Post View Post/Check IP Print Post    Move Post (Custodian/Admin Only) Ban Poster IP (Custodian/Admin only)

My bike doesn't have the thunderstorm heads that you do, so the jetting won't be exactly the same. I have to stock needle and had 2 washers under it when I had the V&H on it. I've yet to hear anyone on here say anything positive about any of the needle options that come with movable clips on them. I'd definitely try switching back to the original needle and work from there.
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Ratbuell
Posted on Wednesday, August 29, 2018 - 09:48 am:   Edit Post Delete Post View Post/Check IP Print Post    Move Post (Custodian/Admin Only) Ban Poster IP (Custodian/Admin only)

I've never changed a needle. 45/190/2.5 turns works on just about all my bikes. My S1W with factory race kit runs 48/190/2.5. I think my stock-exhaust, stock-intake, thunderstormed S2 was a 42/190/2.5.
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Upthemaiden
Posted on Wednesday, August 29, 2018 - 09:58 am:   Edit Post Delete Post View Post/Check IP Print Post    Move Post (Custodian/Admin Only) Ban Poster IP (Custodian/Admin only)

My normal S1 was running 45/190(I think)/2.5 turns/2 washers under the needle with a forcewinder and V&H and was running perfectly. Far from perfect before I added those washers.

Now that I switched to the stock exhaust and airbox I switched to a 42 pilot and removed the washers. Didn't mess with the pilot or the 2.5 turns. It had a bit of a sputter, so I put one washer back in. It's better, but not perfect. I picked up a 45 pilot and am also going to put that second washer back.

Bike still runs strong but there's definitely a loss in power. I don't notice it for normal riding, but I used to be able to give it a handful of gas and a light tug on the bars and the front wheel easily came up. Now if I want the front wheel off the ground I have to get the rpms way up, load the front suspension, wide open throttle and throw my weight back, and it still doesn't come up *that* easily. Honestly that's probably a good thing though.
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Lynrd
Posted on Wednesday, August 29, 2018 - 11:30 am:   Edit Post Delete Post View Post/Check IP Print Post    Move Post (Custodian/Admin Only) Ban Poster IP (Custodian/Admin only)

It’s not a good thing. The front tire wears out faster if you keep it in contact with the road.
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Mike_lee
Posted on Wednesday, August 29, 2018 - 01:58 pm:   Edit Post Delete Post View Post/Check IP Print Post    Move Post (Custodian/Admin Only) Ban Poster IP (Custodian/Admin only)

so the washers that were added, were added below the clip that was in ______ position.
: )
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Bluelightning
Posted on Wednesday, August 29, 2018 - 02:08 pm:   Edit Post Delete Post View Post/Check IP Print Post    Move Post (Custodian/Admin Only) Ban Poster IP (Custodian/Admin only)

The washers always go below the needle to shim it up. I just had to go up on mine from a 48/190/2.5 and 3 shims under the XL needle to a 200 main. The O2 sensor shows it being just a touch rich at idle and in the intermediate, but goes crazy lean at 3500rpm and a 3/4 or better twist of the throttle. But then again, my bike is far from stock.
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Mike_lee
Posted on Wednesday, August 29, 2018 - 02:21 pm:   Edit Post Delete Post View Post/Check IP Print Post    Move Post (Custodian/Admin Only) Ban Poster IP (Custodian/Admin only)

you shimmed an XL needle? I thought that was the whole premise behind those was not having to shim.
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Williamscottrobertson
Posted on Wednesday, August 29, 2018 - 02:46 pm:   Edit Post Delete Post View Post/Check IP Print Post    Move Post (Custodian/Admin Only) Ban Poster IP (Custodian/Admin only)

Easiest to buy a CVP kit for 60 bucks, includes slide drill bit jets and correctly tapered needle, thumb air screw, ect. Pop in the 45/190 and go have fun.
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Mike_lee
Posted on Wednesday, August 29, 2018 - 02:57 pm:   Edit Post Delete Post View Post/Check IP Print Post    Move Post (Custodian/Admin Only) Ban Poster IP (Custodian/Admin only)

My current set up is a cvp xl needle, 46 pilot (which cant be stock,right?)42-45-48?)) 200 main (stock) and cvp thumb screw i thought it was 2.5 turns but ill recheck that.
Forcewinder and v&h ss2r
I was under the impression that if you installed the xl needle, enlarging slide holes was not necessary. Even if i drop the 200 to a 190, that wont affect anything until 3/4 throttle, correct?
Thanks for all the help by the way : )
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Upthemaiden
Posted on Wednesday, August 29, 2018 - 03:26 pm:   Edit Post Delete Post View Post/Check IP Print Post    Move Post (Custodian/Admin Only) Ban Poster IP (Custodian/Admin only)

Just to make sure I'm clear.... the XL needle you have, is that just an aftermarket needle made for the CV carb, or was it the needle out of a Harley XL(sportster)? I'm assuming the first but just wanted to make sure.

I'm not entirely sure how changing the needle would affect whether or not you drilled out the slide hole. If I remember right, drilling that hole out is supposed to change the speed that the slide goes up and down. Changing the size/taper of the needle will only affect how much gas passes by it in various positions. Someone who's actually good at this stuff can say if any of that is right or not.

Have any of you guys drilled out that slide hole at all? I remember reading a bit about that a while back but never messed with mine, and forgot it was something that people did.

You're correct about the 200/190 jet, that's for full throttle. I think most of the riding you're doing is probably run off of the needle, which comes in around 2500ish rpm and goes until the throttle is almost all the way open.

Again, feel free to correct any of that if you know more about this than I do. I certainly won't argue about my ability to be wrong, but that's the current information I've got stored in my brain.
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Mike_lee
Posted on Wednesday, August 29, 2018 - 03:55 pm:   Edit Post Delete Post View Post/Check IP Print Post    Move Post (Custodian/Admin Only) Ban Poster IP (Custodian/Admin only)

The needle i have is an aftermarket CVP needle # cvp-xlndl. Prob the same one that comes in the kit william referred to. The one that came out is the one with 5 notches at the top. That one had three washers under the clip, which was on the 3rd position on needle.
I read up on the cv 101 that ken sent me(thanks ken: ), that and this link...
http://www.nightrider.com/biketech/hd_cv_mods.htm# slide_detail
Which i think is where it stated if the xl needle is used, drilling is not required.
Of course its raining now so im not gona go play with it. Man i miss my garage.

On a side note, i just got my other carb back, the one that was pissin gas out the intake. Turns out it was the fuel jet? The one thats hooked to the float.
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Ratbuell
Posted on Wednesday, August 29, 2018 - 06:15 pm:   Edit Post Delete Post View Post/Check IP Print Post    Move Post (Custodian/Admin Only) Ban Poster IP (Custodian/Admin only)

Float needle.

Float pushes up on its lever. Lever pushes needle into the seat machined into the carb body. Fuel flows through that seat when the needle isn't pushed into it, raising the float and pushing the needle into the seat. Use the fuel, the bowl level drops, lowering the float, which lowers the needle off its seat and opening the hole for fuel to flow in and raise the float again.
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Mike_lee
Posted on Thursday, August 30, 2018 - 05:29 am:   Edit Post Delete Post View Post/Check IP Print Post    Move Post (Custodian/Admin Only) Ban Poster IP (Custodian/Admin only)

thatd be the one. thank you for clarifying.
its been a few days since I had the bike out but took it to work this morn..i duno if its in my head or not but she runs pretty good. maybe I just get used to the power after riding it and once I stop for a bit and get on her again, the big grin returns.
I picked up a cpl jets (45/190)yesterday and will swap those out later.

another side note, I saw St Pauls is going through some management changes, is Lance still going to be around? sure hope so.
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89rs1200
Posted on Wednesday, September 05, 2018 - 02:11 pm:   Edit Post Delete Post View Post/Check IP Print Post    Move Post (Custodian/Admin Only) Ban Poster IP (Custodian/Admin only)

St Paul HD has changed ownership.
Lance and the gang of parts people are still there.
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Mike_lee
Posted on Wednesday, September 05, 2018 - 07:26 pm:   Edit Post Delete Post View Post/Check IP Print Post    Move Post (Custodian/Admin Only) Ban Poster IP (Custodian/Admin only)

Thats good news...thank you.

I swapped the jets mentioned in my last post and now its backfiring on decel. Not bad mind you but more than previously. This indicates a rich condition correct? In decel, it would be the idle circuit, correct? Pilot, not main?
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Ocbueller
Posted on Wednesday, September 05, 2018 - 08:58 pm:   Edit Post Delete Post View Post/Check IP Print Post    Move Post (Custodian/Admin Only) Ban Poster IP (Custodian/Admin only)

Replacing the slide diaphragm in my carb solved popping on decel.
Steveh
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Ratbuell
Posted on Wednesday, September 05, 2018 - 10:58 pm:   Edit Post Delete Post View Post/Check IP Print Post    Move Post (Custodian/Admin Only) Ban Poster IP (Custodian/Admin only)

Yes, throttle closed is pilot jet.

And mix screw. How many turns?

I always thought popping was LEAN, not rich. Example would be my 91 Daytona turbo - I have an air-fuel gauge hooked to the O2 sensor and can literally watch the mixture. Coldstart, when the EFI is in "choke" mode and running rich, I get no decel pop. Warmed up, because I have no muffler and a gutted cat on the car's aftermarket 2.5" exhaust, I get some decel popping when the mix swings lean. Doesn't worry me since I watch the mix swing right back to stoich...but it's definitely a lean thing on that one.

Can also be caused by an exhaust leak.
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Mike_lee
Posted on Thursday, September 06, 2018 - 04:31 am:   Edit Post Delete Post View Post/Check IP Print Post    Move Post (Custodian/Admin Only) Ban Poster IP (Custodian/Admin only)

Mix screw is 2.5 out. I experimented with that hoping itd be a quick and easy fix.
I could very well have the lean/rich thing backwards. Ill swap the other pilot and see what happens.
When i put it all back together i checked the rubber on the slide for tears. The slide was on there previously so im fairly certain its a jet.
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Ratbuell
Posted on Thursday, September 06, 2018 - 09:36 am:   Edit Post Delete Post View Post/Check IP Print Post    Move Post (Custodian/Admin Only) Ban Poster IP (Custodian/Admin only)

It could also be an air leak at the carb gasket, where it mates to the intake...
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Mike_lee
Posted on Thursday, September 06, 2018 - 09:43 am:   Edit Post Delete Post View Post/Check IP Print Post    Move Post (Custodian/Admin Only) Ban Poster IP (Custodian/Admin only)

or even the rubber boot from carb to intake?
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Ratbuell
Posted on Thursday, September 06, 2018 - 10:11 am:   Edit Post Delete Post View Post/Check IP Print Post    Move Post (Custodian/Admin Only) Ban Poster IP (Custodian/Admin only)

That's what I was talking about, the rubber donut that the carb slides into. If it catches and bunches the rubber, you get a gap and a leak.
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89rs1200
Posted on Thursday, September 06, 2018 - 10:33 am:   Edit Post Delete Post View Post/Check IP Print Post    Move Post (Custodian/Admin Only) Ban Poster IP (Custodian/Admin only)

Ratbuell has a good point. Have replaced intake gaskets on all of my Buells.
There is usually little indication of a problem other than not running quit right or the inability to get the jetting correct.
The rubber gaskets between the intake manafold and heads, also the one Ratbuell talks about, get hard and leak air, which leans out the fuel mixture.
May not be your problem, but needs to be addressed if they have yet to be replaced.

Concerning the float valve. Anyone else experience the following?
1) Due to alcohol in the fuel, have been replacing these every three to five years. They become hard and will not seal. Gas then continues to flow into the heads and oil.
2) Float height adjustment, as shown in the manual, does not provide sufficient pressure on the valve to shut off fuel flow. I suspect harder rubber is used on the newer float valves. I now turn the carb upside-down and adjust the floats to level with the carb. body.
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Mike_lee
Posted on Thursday, September 06, 2018 - 10:51 am:   Edit Post Delete Post View Post/Check IP Print Post    Move Post (Custodian/Admin Only) Ban Poster IP (Custodian/Admin only)

rat always has good points.
I do have the 2 manifold seals that I was going to replace in the winter. I will order the seal from carb to manifold tonight and maybe even a new gasket from carb to mount and I may not wait til winter.

my float valve just went and I ended up takin it to my mechanic cuz ive never experienced the symptoms you just described. but it definitely was float valve. had a nice little groove around the point where it seats.
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Ratbuell
Posted on Thursday, September 06, 2018 - 10:58 am:   Edit Post Delete Post View Post/Check IP Print Post    Move Post (Custodian/Admin Only) Ban Poster IP (Custodian/Admin only)

rat always has good points.


...but usually I comb my hair right, and the points don't show...

A finger-schmear of plain ol' engine oil on either the carb snout, or the inner edge of the intake boot, usually keeps the carb from sticking and pulling the rubber.

For the float valve...just turn your petcock off when you turn the bike off. That way, if it does allow fuel in...it's only what's in the line, not the whole tank. Leave the bowl full, no need to run it dry, just flip the switch when you park. You'll drive off a few times and forget to turn it back on - usually with an audience - but after the fourth or fifth time, you'll start to remember...
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Upthemaiden
Posted on Thursday, September 06, 2018 - 01:39 pm:   Edit Post Delete Post View Post/Check IP Print Post    Move Post (Custodian/Admin Only) Ban Poster IP (Custodian/Admin only)

I'd say it's most likely lean. When I had my XB9 it ran fine with the stock exhaust, but I'd switch back and forth to the Hawk exhaust when I wanted to make some noise and it always popped pretty good on decal. There was some kind of issue with the computer on my bike and would not load new maps to it, so I was never able to load the race map for it to run properly, so I just had to deal with the popping, but it was definitely on decal.

Float valve on mine went last year. It was parked at work and left a nice puddle of gas on the ground for me. I rebuilt the carb, replaced the float valve, changed the oil twice, and make sure I turn the switch off when I park now. For a while I'd turn it off 30 seconds before I parked just to drain the of the gas out of the line, so if it did get stuck again, there wouldn't be much to leak. Been doing good since.
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