I really appreciate the input. I’m trying to learn a bit before pulling the carb off and taking it apart again. The gurgling sound is a perfect description of the under 1/8 throttle position/ off throttle sound. It’s not particularly bothersome, but it has more gurgling now than it did before going through the carb and more than it ever had through the years.
I’m no longer getting any pop, unless the gurgling is considered popping?
I don’t know what enlarging the hole in the slide provides... anything in the low circuit?
Will changing the clip position on the needle change anything on the low circuit?
I really appreciate the input. I’m trying to learn a bit before pulling the carb off and taking it apart again. The gurgling sound is a perfect description of the under 1/8 throttle position/ off throttle sound. It’s not particularly bothersome, but it has more gurgling now than it did before going through the carb and more than it ever had through the years.
I’m no longer getting any pop, unless the gurgling is considered popping?
I don’t know what enlarging the hole in the slide provides... anything in the low circuit?
Will changing the clip position on the needle change anything on the low circuit?
No, gurgling is Stormy Daniels, the pop is a small explosion.
Drilling the hole works with the lighter spring installed and controls the speed of the slide piston, nothing to do with the low side fuel control.
Here is the issue on the needle, a stock Harley needle is adjusted by washers, not slots with a clip meaning the needle isn't stock but aftermarket.
Here's what we know:
A 45 low and 185 will work, not a 150
A new diaphragm is installed
New intake seals are installed
Here's what we don't know"
What needle is in it,, isn't a stock one
Is the needle installed correctly in the slide since the clip came off, should have a washer involved on top the clip type needle to keep the needle from floating upwards
Is the accelerator pump working, could be your stumble, look at that before pulling the carb
Is there any black smoke present determining a choke plunger problem for a stumble
Do you have a diaphragm fuel petcock, could be bad pulling fuel by vacume and a stumble.
Do you have new plugs in it
Was the carb circuits cleaned well with carb cleaner and compressed air
Here is the problem without a AFR meter, we don't know if the stumble is lean or rich so need to check trial and error
Last edited by 1997bagger; 09-09-2018 at 09:52 PM.
Thanks for the information.
I didn’t realize the needle wasn’t stock. It has no washers, just a circlip and a little drop in cage on top.
The chart’s a big help in my understanding too.
The accelerator pump is working. I checked the petcock with a vacuum pump... it holds pressure when the vacuum line is removed and flows gas when vacuum is applied to the vacuum line. New spark plugs. The Indy shop I took it to disassembled and cleaned the carb.
The only thing I take exception with is that the 45 & 150 don’t work. It worked for a couple decades. But I’m baffled as to just how it worked so well. Maybe the needle has deteriorated through the years.
Without really knowing what made that 150 work. I think I’ll change the 150 for a 180 and change the needle and spring too. Seems to be the consensus tried and proven setup.
Do you have a recommendation on a source for the parts?
Gogobeck, Ive got a similar set up as you, '98 Evo Dyna, SE slip on's with stock headers, Big Sucker intake, Dyna 2000i ignition and EV13 cam. I bought an already modded carb, came with a 48 pilot jet and a 195 main jet, lighter spring and a drilled slide. Thoes jets were way too rich. Ive since backed them down to a 45 pilot and a 185 main and could possibly come down to a 180 main jet. This winter Im going to return to a stock non-drilled slide. Before all these mods I got a steady 48-50mpg. After engine mods (cam, ignition, etc) and extra rich jets I dropped to about 32 mpg. Since backing down to 45/185 jets, Im at about 40 mpg. I get my CV carb parts and jets from CV Performance, never had a problem with their stuff.
Thanks, I missed your post earlier... sounds like a very similar setup to mine.
I went into the carb today to check things over again.
The needle jet is a brass unit with U146 inscribed. It has 5 positions set with a clip. It was in the 2nd from business end setting. The guy that cleaned my carb and put the VTwin kit in it told me he was unable to use the middle position. It seems the steel clip had taken a toll on the brass needle. I tried the other positions and the bike wouldn’t run... I then looked for a washer figuring to use a lower attitude and a washer to get to the middle. I didn’t have anything suitable.
I put the clip on the needle in the center groove and put a pair of needle nose to it.
In the center position and backing the low circuit mix screw to about 3 turns out, she's running well again. There’s still a tad bit of rough just off idle position (1/16 throttle position) and a very small hesitation when going from say 1/2 throttle to full... but she catches and goes.
I don’t know what this needle is and I don’t trust it to not lose the clip again at some point. I still suspect the slide spring has been changed out. It could be as simple as putting the old slide back in with the enlarged hole, or drilling the new slide. But I really want to know what’s in there, so I’m going to locate a 180 main, stock spring and a new, shim with washers, needle. But for now, I’m pretty happy with how she runs, and with the sound from the mufflers. It’s no longer a wet sounding gurgle.
Thank you all for the input, I learned quite a lot.
I finally received my parts from CV-Products... Hurricane Florence stopped The USPS in their tracks in my area. The original order still shows as in route to next destination in the USPS system. CV-Products stepped up and shipped a replacement order, it made it in 3 days from Nevada to Virginia. Excellent customer service.
The emulsion tube, jets and slide needle were all Dynojet pieces... I couldn’t get them dialed in correctly. Maybe they need a different float adjustment or possibly the slide needle was just worn out, or when running their setup the slide hole has to be drilled out to 1/8”.
No knock on DJ, this setup ran great for 22+ years.
After getting the intake free of leaks, I installed CV-P’s Velocity emulsion tube, needle jet and Velocity slide needle. I adjusted the idle circuit according to the instructions on their website... it seems to be dialed in correctly at about 1.75 turns out from seated.
She’s smooth at all throttle positions, responsive when I roll on the throttle, no gurgling or backfiring on de-acceleration.
I took a nice 130 mile ride this afternoon... fuel consumption is at 43 mpg, and I was running her hard at times through the mountains and about 30 miles of highway at 70 mph.
09-09-2018 | 06:28 PM
