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[Magnumeng]

Hello guys,

A buddy bought a used 2003 duece carbureted acouple months ago...  the bike has less than 15000 miles on it.  Here is the problem... if you ease on the throttle yo can go as fast as you want..  but if you are gun it, it races up to 3000-3500 and loses all power.  The engine does not quit, just loses all power.

Set up
Idle - 900-1000
Engine - 88TC
Pipes - V&H short shots with baffles
Main jet - 185-195 (same results with all jets)
Slow jet - 46
Slider - dynojet thunder slide
Spring - stock
Needle - dynojet replacement with the clip on the 3rd groove down.
Mixer screw - 2.5-4 turns out per jet with minor change when it cuts out

[Kingspoke]

Another good source, is Harley Tech Talk.

[Trapperdog]

Fuel filter or main jet clogged. Or possibly float set too high

[FlaHeatWave]

Sounds like the clutch...

[RonandJanet]

Does sound like the clutch may be slipping.

[Trapperdog]

Yea, the above. I read the post wrong

[CVODON]

If the clutch were slipping the engine would continue to increase in RPM, this would not result in the engine losing power, just lack of further acceleration. But once again the engine would keep on reving, you just wouldn't go faster. But he says the engine loses power which to me means no advancement of RPM.

[grc]

If the clutch were slipping the engine would continue to increase in RPM, this would not result in the engine losing power, just lack of further acceleration. But once again the engine would keep on reving, you just wouldn't go faster. But he says the engine loses power which to me means no advancement of RPM.

Exactly.  We need a much better description of what exactly is happening before we can offer meaningful suggestions. 

Magnumeng, please tell us exactly what the engine does when you suddenly apply full throttle.  Does it rev up but the bike doesn't accelerate, which would be a good indicator of clutch slippage, or does the engine fail to increase in rpm until you back off the throttle, which could indicate a severe carburetion problem? 

Jerry

[wfolarry]

Sounds like the slide's not lifting. Check the diaphragm.

[Magnumeng]

After a long weekend of tinkering...

It is a fuel supply problem.. i pulled the peckcock out and noticed rust and tank liner on the filter... so i flushed the tank four or five times straining each time to see what was coming out... half inch square chunks of paint came out..

Put it back together and it runs way better.  Now it starts sputtering at 4000rpm, but keeps slowly climbing in rpm. If i back off the throttle a hair it powers right past 4000rpm with out sputtering at all.

Current jetting is 190/45 mixer screw 3.75 turns out

[koko]

Throw out the dyno jet & return it to stock configuration.

[grc]

Odds are quite good that the internals of the carburetor have also been "gunked up", not just the tank.  A complete disassembly and cleaning would be a good idea on a carb that old, followed by reassembly with new seals and gaskets.  Get the original specs for the carb as it came from the factory, set the float level to spec, and compare the existing jets to the original specs.  Unless significant mods were made to the engine, jet changes other than the pilot jet shouldn't have been necessary.  Make certain the diaphragm of the slide is in good condition and air tight.  Find the directions for the slide kit if you can (online search will probably be necessary), set the needle position to the standard setting if it isn't already at that setting.  After all that, if the bike still doesn't run properly you may need to get it on a dyno to check AFR's and ignition system operation under varying loads and rpm.

Jerry