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zuna
17th October 2007, 01:23
whats up brothers! i just finished chopping my 81 ironhead. After fabbing the frame and tins. We redid the top and bottom end. After about 500 miles i had to replace the points again so i went with an electronic ignition. Also i replaced the generator, voltage regulator and battery. I road another 1000 miles and now shes acting up. It is like she isnt getting any power. She fires right up but accelarates very low and feels like shes only running at half power. I replace the fuel line and rebuilt the carb hoping it was just a fuel problem. But its still the same. Any wisdom will be greatly appriciate.

alleydude
17th October 2007, 01:35
If I had to guess, I'd say a carb adjustment problem. What carb are you using.

Welcome to the forum!

prettyponyofdoom
17th October 2007, 01:39
Welcome to the forum from Illinois. We need pictures of that bad-scooter!

As far as running, have ya checked the plugs?
I am sure one of the iron pro's will chime in here pretty soon....

good luck.

ericfreeman
17th October 2007, 01:50
Welcome! I'd pull the petcock and check the screen to be sure you're getting good fuel flow from the tank. It that's not the problem, I'd have to agree with the others on a carb problem. Possibly a clogged float needle valve or something similar.

Eric

Moon Wolf
17th October 2007, 02:54
Check for crud in your fuel filter first, even if the tank was brand new.

zuna
17th October 2007, 03:04
Im using the orginal carb. I rebuilt it today. I also replaced the fuel filter and fuel line. You guys think it could be the petcok? Ill try that tomorrow. If I need to adjust the carb any suggestions?

zuna
17th October 2007, 03:26
Welcome to the forum from Illinois. We need pictures of that bad-scooter!

As far as running, have ya checked the plugs?
I am sure one of the iron pro's will chime in here pretty soon....

good luck. Yeah man i did they were fouled pretty bad but i replaced them still the same thing.

zuna
17th October 2007, 03:26
Check for crud in your fuel filter first, even if the tank was brand new.

Yeah man I replaced the fuel filter and the fuel line.

IronMick
17th October 2007, 03:41
... I road another 1000 miles and now shes acting up. It is like she isnt getting any power. She fires right up but accelarates very low and feels like shes only running at half power ...

I assume it rode fine for the 1000 miles.

Is it running on both cylinders, but weakly? Or is it running on only 1 cylinder?

Will it act up only when riding? Or will it act up also at idle with bursts of throttle?

Inconsistent spark? Weak coil? Loose spark plug wire or cap?

I am just guessing.

zuna
17th October 2007, 03:45
I assume it rode fine for the 1000 miles.

Is it running on both cylinders, but weakly? Or is it running on only 1 cylinder?

Will it act up only when riding? Or will it act up also at idle with bursts of throttle?

Inconsistent spark? Weak coil? Loose spark plug wire or cap?

I am just guessing.

Yeah man she ran great! I pulled both the plugs replaced them and they are both getting good fire. Yes when im at idle and hit the thottle she dosnt seem to be getting full power. If it is the coil is there anyway to check it? she seems to be hittn on both cylnders just weak.

Moon Wolf
17th October 2007, 03:47
By all means check the petcock. If there's crud, that's where it will get caught first.

zuna
17th October 2007, 03:51
Yeah man she ran great! I pulled both the plugs replaced them and they are both getting good fire. Yes when im at idle and hit the thottle she dosnt seem to be getting full power. If it is the coil is there anyway to check it? she seems to be hittn on both cylnders just weak.

Yeah man ill check that out tomorrow and let you know. I dont know why i didnt check it. The fuel filter was full of shit so it could be the petcock

IronMick
17th October 2007, 04:02
... If it is the coil is there anyway to check it? she seems to be hittn on both cylnders just weak.

Primary coil resistance [between electrical terminals] should be 3.3 to 3.7 Ohms. Secondary resistance [between spark plug connectors] 16,500 to 19,500 Ohms.

Disconnect all connections from coil before testing.

zuna
17th October 2007, 04:03
Primary coil resistance [between electrical terminals] should be 3.3 to 3.7 Ohms. Secondary resistance [between spark plug connectors] 16,500 to 19,500 Ohms.

Disconnect all connections from coil before testing.

Thanks brother ill see what i can find tomorrow

frenchandy
17th October 2007, 08:33
i suspect your valve clearences have closed up- if your bikes getting hot thats a symptom,if its the case dont run the bike you could end up damaging it

alleydude
17th October 2007, 11:28
Have you looked at the plugs since you changed them?

Fe Head
17th October 2007, 12:05
The coils could be checked using an Ohm Meter . The primary winding should be between 3 to 4.5 ohms.

You said you migrated to an electronic ignition? Did you also change to a recommended coil ohm ratiing for that system?

It sounds to me that you are running way too retarded a timing. Check with a light statically or with a timing light dynamically using a clear plastic plug in the left sided timing hole and at about 2200 RPM's.

If it is backfiring sometimes you could have the magnetic pickup coil mounted 180 degrees out of position and would then be runnining the back cylinder off the front (smaller) interrupt block and visa versa.

Check out these and see if your installation was correct.

All the best

flathead45
17th October 2007, 21:58
also check to see if ya got the wires on the coil right. if the small (not plug) wires are hooked up backwards you will get a week spark that may have trouble jumping the plug gap when the motor gets hot

I'm leaning towards electrical problems since ya already went through the fuel system

-stinky-
18th October 2007, 03:02
Check the pushrods and see if your tappets are still adjusted correctly. After a fresh rebuild they may have come out of adjustment.

zuna
21st October 2007, 01:26
Thanks for all the wisdom brothers! It was the push rods one was almost worked completely out. We set em right and shes back on the road. Thanks agian!!!!!!!!!!!!!