I rescued a 1995 Wide Glide (first Harley, fourth bike) with 39k miles that's in pretty good shape except the rear cylinder keeps fouling plugs.



The PO told me that this was the case and put fresh NGK plugs in when I bought it. He also suggested I try a second coil, which he had bought but never tried. I ran the new plugs and the new coil right off. Within a couple hundred miles, the bike spit and sputtered like I was running out of gas. I'm determined to get the bike tuned and running smoothly myself and wanted to get some help. This is long, but I've read many posts and know that everyone here asks good questions to make sure the OP has covered the easy bases.

The bike seems mostly stock except for some chrome and Freedom Performance Patriot LGs with the baffles installed (that's me goofing around with a Nitron shock).



It still has the original CV carb, plug wires, coil, ignition module, everything. The air filter that was on it is HD, but no longer available.



For that first 200 miles, I could always hear some sputtering in the lower gears up to 3000 RPM; it seemed like the bike was okay once I got up to 4th and 5th. But as I got closer to that failure, the bike started to sound weak throughout the range. One day I was cruising in 5th and decided to open it up; when I did, it immediately choked down like I was out of gas and I didn't think I was going to make it home the last five miles. The bike was bucking and sputtering in all gears and at any RPM. I pulled the plugs and found that the rear was dry soot rich and the front was glass brown lean.



I put in a new set of HD plugs and the bike instantly ran better, but only for about 25 miles before the rear plug was black again. My first step was to put on a new K&N filter, strip the carb and clean it, and replace the three manifold seals with HD parts. I also removed the breather hoses to the carb inlet and put on a breather kit (it was spitting some oil into the filter). The carb was basically stock with Keihin branded jets (175/45), but an odd looking adjustable needle marked "0146". Notice there is no position 2 or 3 for the E-clip.



The idle mixture screw was backed out 11.5 turns... almost falling out! The other thing I did was put the OE coil back on, even though both coils tested good on the primary and secondary. I also checked and cleaned all the grounds and redid the connections on the electrical panel. Oh yeah, I do RTFM (the offical one) extensively.

I think the E-clip was in the wide gap but don't remember. I put the clip in what might have been the 4th slot (more rich) and put the three washers that were in there ON TOP of the E-clip (which I later learned was incorrect). The bike ran decent, but both plugs were completely black and sooty, confirming that I was way too rich on the needle. So I pulled the carb again and put the E-clip at the top and removed all the washers. I also bought a new accelerator pump diaphragm and a new slide from HD because the vac port had been drilled out to a measured 0.135-inch, and I had read that this was not good. I removed and cleaned the enricher to make sure it was seating all the way. I rode this around for 40 miles and both HD plugs that had been sooty black looked just right. Notice that the black was burned off both plugs with a little more still left on the rear plug (right).



So I took a short trip of 130 miles with mostly highway and some stop and go lunchtime traffic. The bike ran great until the last 20 miles, then I could tell it was starting to sputter again. I pulled the plugs and found the rear was rich and the front was nearly perfect.



By this time, my new 8mm Magnecor wires showed up, so I installed them and switched the plugs around. The rear plug cleaned up in the front cylinder and the front plug blacked out in the rear.



The bike starts perfectly everytime and idles right at 1000 RPM. The engine does not respond to the mixture screw at all, although I've cleaned it with carb cleaner and air twice. All of the packing components are there. The float is adjusted properly. On that 130 mile trip, I averaged only 30MPG on non-ethanol 87 octane with a shot of Seafoam. I can't tell that there's anything wrong with the engine because it pulls hard and runs great, but it does sputter and stutter a bit under partial throttle in the lower gears. I don't have any backfiring at the pipes or the carb. The pipe tips are mostly sooty, but I never see any color smoke coming out of them.

I think I've done everything I can without pulling the heads. Here are pictures of the intake valves where the rear is showing a little blackening above the valve. I don't know if this means anything.





What is my next step? I have not purchased a new coil, but the two I have test okay. I have not tried a new ignition module yet. I have not switched the plug wires at the coil to see if the issue is in the ignition, but I just read about that tactic, so can try, but don't expect that will be the issue. I could probably try to do some more work to the carb, including trying different jets and such, but the bike runs great except for the rich condition at the rear.

Thanks for any help.

 

I forgot to say that I tested for spark and both plugs looked the same. I tested cold compression and got 120-130 in the rear and 90-125 on the front. First number was initial reading, second number was final reading, so looks good to me.

 

Where did you leave the mixture screw set at

 

I started at 2.5 turns out and made several adjustments from closed to 5 turns out and nothing changed. I left it at 2.75 turns out while idling at about 1000 RPM. All I have to check RPM is an HD bar clamp integrated tach, so it bounces pretty good at that low an RPM.

 

I'd make sure you have the spring washer and oring on there and that you have the right mixture screw and it's not damaged at all. I'm sure you know what it should look like but this is it just in case.

It's possible your check ball isn't seating in the accelerator pump and it's sucking fuel from there instead of only when it's pumped. Have you run it air cleaner off and watched the carb and slide and accel pump nozzle? I'd rule out the mixture screw and accel pump nozzle before I go too far.

Do you have a stock main jet and emulsion or is that needle main and emulsion aftermarket? Also are you positive that is a 45 pilot? The numbers can be hard to see sometimes without a flashlight or magnifying.

 

I've got a stock screw which looks to be in good shape and all the packing parts are there. I suppose it wouldn't hurt to order a new packing kit.

I didn't think about the check ball on the acc.pump. and I have not run AC off. So I should pull that and watch for no fuel coming from the accelerator except when I roll on the throttle? I've watched that with the bike NOT running and didn't see any fuel leaking out, but I'll check the running condition.

The jets look stock to me. The emulsion tube is really plain; only has two holes 180-degrees apart at the very top of the tube. The main and pilot jets are Keihin brand and are definitely a 175 and 45, so I assume they are stock or at least OE to the carb (my manual says stock should be 165 and 42).

I guess the trick is to minimize the rich condition on the rear as it probably won't go away completely. I'm thinking about just going ahead with a rebuild and tuning kit from CVP and see what I can do with it from scratch.

The only thing that bothers me is the blackening on the rear intake valve and stem. I'm wondering if there's a valve problem on the back that carb work won't solve?

 

I'd make sure your check ball is free. Make sure you got the oring and diaphragm and spring is in correctly and that it's functioning right when you twist the throttle. Shake the bowl you can hear the ball rattle. I think that needle has to go. I have a spare adjustable needle and an extra new mixture oring if you want it. You might even want to try a 42 pilot to see how it runs. I think if your accel pump is fine and mixture fine I'd swap that needle and maybe the pilot and see what I get.

 

I would get rid of that needle also. Get a CVP or a stock needle. You may need to shim the stock needle, but do that later after she is running right.

Or use the CVP needle without any shims, it don't need any.

Did you check for intake manifold seal leaks? Your plugs are showing improvements with the fixes your doing. Leave the jets at 45 and 175 for now but definitely get a new needle. YD

 

Thanks guys... I agree on the needle; it's just goofy. I'm having a hard time sourcing the CVP needle right now as the site isn't taking orders and JP is out of stock unless I order a full kit for a TC88 or 95 (probably same parts). I'll probably try to source a stock needle from an online dealer or my dealer if he thinks he can get it. There are a few part numbers to choose from; any specific recommendation?

I replaced the intake seals and realigned the manifold but haven't checked for a seal leak after. I know I should do that anyway even with new seals, and will this weekend. What do you do if you line up the manifold correctly with new seals and still have a leak?

 

Cv site has been down. Been waiting to order a mixture set or ezjust since the weekend. If you want to try changing out a few things before you buy stuff I have a new mixture oring, needle and 42 pilot if you want to give those a shot. Tell me which needle you want, left or right and pm me an address before the morning and I'll mail it out. Up to you just an option if it helps