hey yall

i have posted about this recently (https://www.hdforums.com/forum/sport...-throttle.html), but i have made a handful of repairs since posting and am still having the same problem.

Bike:
-2001 Sportster 1200S, 37,000+ miles, recently bought it used and have not been able to ride it much, previous owner had it garaged for a year
-Currently running HD baffleless slash cut pipes, also have stock pipes.
-Carb: 45/195, mixture screw 2 turns out, 0 shims on needle (removed 1 that was there)

Problem:
-Bike wants to die when taking off from a stopped position in 1st gear
-Nearly have to pin the throttle and let the clutch out slowly when pulling out of a red light or stop sign.

Repairs:
-The idle cable was shredded, replaced that.
-Rebuilt the carb as there was a slightly melted diaphragm and somewhat corroded acceleration pump diaphragm.
-Replaced all 4 spark plugs
-Tested for air intake leaks by spraying carb cleaner around the intake manifold. Stalls only when i hit the manifold from the left side of the bike, bottom of the manifold where it meets each cylinder. Replaced both gaskets, retested and the bike stalled again.

Other info:
-There could be a small exhaust leak at the base of the push rods on the front cylinder (is this possible?). Cleaned the carb out with a bit of Sea Foam and think i noticed a bit of white smoke escaping from this area. Also noticed that significantly more smoke came out of the exhaust of the rear cylinder than the front, but maybe this is because the exhaust system is joined by a cross pipe that runs below the air filter. White smoke could have also been from some Sea Foam that dripped on this cross pipe. Nonetheless i cant rule out the possibility of the leak at the base.

Do yall have any suggestions, ideas, comments? Could this be the ignition coil? I have not checked the petcock-filter, vacuum, anything. Could it be here? This is making the bike nearly unrideable.

 

How does it idle? Will it take throttle when not under a load?

It sounds a lot like a carb blockage - would suggest removing the carb, cleaning it VERY well, and running a small wire (like an old high E guitar string) through all the air orifices to ensure you don't have a blockage.

 

Fuel filter.

 

Start at the fuel tank, remove the gas tap and clean the filter, also flush the tank of any deposits in there. Check gas level in the float chamber. Check and clean pilot jet. If in doubt replace it as they don't cost much, but are easily spoiled when trying to clean.

 

Do you mean that you changed the Intake gaskets and the bike stalled again when you sprayed it or rode it? Did you test/spray the area again after you changed the gaskets?

Also. Do you have a high flow air intake on the bike or the stock one?

An exhaust leak at the base of the push rods would indicate a real bad exhaust valve and if it was leaking there the front cylinder would not run. So I doubt that is it.

Also what do the plugs look like compared to this chart?
http://www.dansmc.com/spark_plugs/sp...s_catalog.html


.

 

-How does it idle? Will it take throttle when not under a load?
It idles well, I can keep it around 900rpm. Though yesterday before a test ride I did let it sit while warming up and after about 5 full minutes of idling it did slowly go down in rpm and then cut out. first time that has happened.
It does throttle without a load, though i can actually time it with the throttle to stall out the engine, watch this (my bike before repairs, but it still happens): https://vimeo.com/46781576
-Ill definitely get back inside the carb and do a thorough cleaning, though I feel i did pretty well the first time around.

Fuel filter-
I am starting to think that this is a possible problem. Ill take it out today. havent looked at it yet.

Do you mean that you changed the Intake gaskets and the bike stalled again when you sprayed it or rode it? Did you test/spray the area again after you changed the gaskets?
-I changed the gaskets then took it for a ride and the acceleration issues remained. when i got home a few minutes later, i sprayed the manifold in the same place as before (left and low) and the engine stalled. i did not test the new gaskets before i went for the short test ride. I have a stage 1 screamin eagle air kit (stock on the 1200S). I believe the plugs are fine-i check them, they were NGK, they looks mostly fine but i replaced with HD brand the other day, so theyre brand spankin new.

Today I tested the spark plug cables-they all came out reading about 4-4.5 except one of them didnt give me a reading at all!! the 1200S have dual spark plug per cylinder. would the bike still run if the cable wasnt sending a spark at all?

 

Until you fix that manifold leak, you're going to continue to have the problem.

With dual plug heads, yes. The cylinder will still fire on the one good plug.

 

Yup - if you still get symptoms after replacing the intake seals, I'd suggest that you take 'em out, grease 'em a little bit, then put the intake back on, tighten LIGHTLY, put the head-breather bolts into the heads, THEN finish tightening the intake manifold-to-head bolts.

 

will some motor oil do?

 

+1 Your still going to have problems.

Follow these guidelines:

7. Install the intake manifold onto the cylinder head intake
ports. The slotted ends of the flanges must point to the left.
8. Make sure the front and rear seals seat squarely against
the cylinder head mating surfaces.
9. Tighten the intake manifold fasteners finger-tight.
10. Install the carburetor as described in this chapter.
11. Install the air filter backplate and air filter as described
in this chapter.
12. Tighten the intake manifold fasteners to 72-120 in.-lb.