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power loss problem 1978 flh

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Old Apr 1, 2008 | 07:15 PM
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Default power loss problem 1978 flh
78 flh top speed only 65mph , good comp. , new electronic ing. , new coil & wires , new carb (s&s G) ,new fuel lines ,filter , petcock , new intake & O-rings ,new ing. switch , new wiring harness . Bike runs strong in neutral but in gear it bogs - stalls .cant keep throwing moneyatit !!! please help !!!
 
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Old Apr 1, 2008 | 07:23 PM
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Default RE: power loss problem 1978 flh
Timing, ignition or cam? Exhaust restriction?
Ron
 
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Old Apr 1, 2008 | 07:32 PM
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Default RE: power loss problem 1978 flh
new cam ,shot-gun pipes with 3" baffels cut down to 1&1/2
 
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Old Apr 1, 2008 | 07:44 PM
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Default RE: power loss problem 1978 flh
Ok, exhaust should work. Are you sure the cam isn't out one tooth or morein timing? It may still run, but really gutless.
Ron
 
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Old Apr 1, 2008 | 08:24 PM
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Default RE: power loss problem 1978 flh
A "G" is a big carb for a '78. Main jet too big (rich). Go down a size.
 
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Old Apr 1, 2008 | 08:40 PM
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Default RE: power loss problem 1978 flh
not 100% sure of timing - timing mark hard to see , dont think carb is to big same prob. with S&S E , motor was built ,S&S rods & pistons with longer than stock stroke ,sifton cam & andrews gears . bike used - fly
 
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Old Apr 2, 2008 | 06:22 AM
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Default RE: power loss problem 1978 flh
An S&S G carb will feed 113" and 124" engines. It is MUCH too large for your 80" Shovel.
You will need to jet up, and in a big way, as the signal it is recieving from your powerplant is not enough to wick gas up out of the bowl.
BTW, what are the jet sizes?
 
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Old Apr 2, 2008 | 10:03 AM
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Default RE: power loss problem 1978 flh
the S&S E worked fine for a few years , then I had intermintint power loss , now I only have power when in neutral , runs very strong - try to ride -now only goes 15 to 20 mph . been trying different parts to fix , nothing works
 
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Old Apr 2, 2008 | 02:02 PM
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Default RE: power loss problem 1978 flh
Something is way out of shape.
Perhaps more than can be diagnosed here in cybertown.
 
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Old Apr 2, 2008 | 02:30 PM
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Default RE: power loss problem 1978 flh
any tests I can do or places to check ?
 
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