800A winter build

[Rowdy1]

I would definetely check the carb for trash. I don't know much about new tanks, but I bet there could have been some microscopic trash in there maybe? Then, I would check the spark plug wires in the plug boots. Pull out the wire and make sure it isn't corroded. If you see corrosion, cut a little of the plug wire off. Get you some electric contact grease and put a little on there when you push the wire back in the boot.

Hope this helps and good luck! I know how frustrating this can be. I got caught out in the rain one day last fall. Water got into my front spark plug boot. This was virtually impossible before with the fatty tank. I didn't know what was the problem and I was convinced it was the carb. I removed the carb and cleaned it at least 10 times before my dad convinced me to check the plug wires..... The symptoms were very similar to yours......

[goddarddr]

once i was running down I-state allof a sudden it started cutting oust sputtering
a plug wire was not seated tight on the plug

[CM33]

Double post.

[CM33]

Any way to test these problems? Ran 2 tanks of seafoam through and it's still doing it. Pulled both plugs and the front one already has some build up after 250 miles of riding. Boots are all the way in as far as I can tell. Took them out and put them back in and the problem is still there. At startup when putting it in first it takes a while for the throttle to respond and start moving and when it does it's revving high and most of the time dies at least once before I can ride away. Once its moving it just stutters on acceleration. Besides tearing out the whole carb and going through it, I'm at a loss. It was running fine for about the first two days with all the modifications. Will this cause any damage if I keep riding while trying to figure out the problem and see of the carb clears itself with more seafoam?

[Rowdy1]

When you pulled the plug wire out of the boot, did you check the wire for corrosion? Also, how fouled is the plug? Get a new plug to make sure the plug is not part of the problem. Can you narrow the problem down to the front or back cylinder? This all still sounds like a spark problem to me. I would even suggest going as far as replacing the plug wire. Orielly's sells solid core wire that will work for these bikes. Go get you a couple of feet of it, and see if that helps.

However, if you check all that and you still have the same problems, it would have to be the carb. I don't know for sure, but I don't think SeaFoam melts trash, so it sounds to me that a complete carb cleaning is in order. Do you have an inline filter between your fuel valve and your carb? That is a must. With a new tank and all the prep you did to it, there is no telling what micro trash might have been in there. Hope you get it worked out.

[CM33]

I could not see any visible wire, but everything looked clean.

The petcock has a filter. Does it need another one?

The problem only happens at low rpms and once I ran a bunch of Seafoam through it, the problem doesn't happen nearly as much.

[Rowdy1]

Yes, I would run an additional in line filter, but that's just me. I don't believe in over filtering the gas.
I would take the carb apart and clean it thoroughly.

If this does not fix it, I would replace the plug wires, as I said before. The wires are in the center of the plug wire. You should be able to see them when you pull it free from the boot.
If that doesn't fix it, I would check the coils.

This is as much help as I can offer. Sounds like you are going to have to get you hands dirty, so Good luck.

[goddarddr]

my fuel valve has the filter screen bilt in, thats all I have had since I put the small tank on
10000 mi,=problem free

[CM33]

Carb is coming off for a cleaning tonight. I planned on removing the main jet and pilot jet and boiling them in water to remove anything in there and then reassembling. Anything else that I should check/clean while I have it off?

[CM33]

Cleaned the main jet and couldn't get the pilot out. Reassembled and the problem is still there. Starting to think I'm chasing an air leak. There is visible gas on the boot of the air cleaner.

[Rowdy1]

Ahh, didn't think of that one. Spray a little starting fluid at the carb intake boot while the bike is idling and if it revs up by itself, then you don't have a good seal there.

[CM33]

Cleaned the main and the pilot. Sprayed the carb boot with starting fluid and it didn't rev the engine. Checked the plug wires and there is no corrosion. Problem is still there. Gave a really loud backfire when I was test riding it after the cleaning. How does the plug only affect low rpm acceleration and not carry on into higher rpms?

The fuel/air mixture screw is still untouched, but could it be running rich and causing these problems?

[goddarddr]

you mighthave already said this, do you have the stock air box?
after market intakes require rejet and air mix screw adjustment

[CM33]

It's the stock air box with the part under the tank removed. You can see the remaining snorkel in the photo above. Would this cause it to run rich? Cobra boulevard exhaust. K&n filter.

[Ivannatinkle]

sounds like a bad coil maybe?

[xfiend]

I think the problem its that your running that snorkle without the air box. Have you rejet? I think you need to rejet if you haven't, then do a not half assed intake mod of some sort whether it be an aftermarket filter or mod the original.

[CM33]

Its time to ditch the stock air filter and do a complete rejet. I plan on running an S&S if I can get it to fit right. Has anyone had any problems with either of Wolf's combinations?

170/52 with stock needle
165/50 with aftermarket

I already have the aftermaket needle in the kit that came with the bike. Anyone notice a big difference in fuel mileage with the aftermarket needle setup? I already have a 2.7 gallon tank and don't really want to lose much more mileage.

[goddarddr]

I followed his performance recommendations in 2007, 165/50 dno needle, with a Dragtron II air box, still runs Grrrrrrrrrrrrreat
50 MPG

[CM33]

Got a link to order the exact 165/50 jets?

[goddarddr]

harley davidson dealer, get the emulsion tube also