1983 Venture needs IGNITION UNIT

[jrich]

I'm just getting started on an 83 Venture project. I have diagnosed a bad Ignition Unit (only on spark plug working, tested all other coils, wires, and plugs by swapping out coil connection with the known good, they all spark when connected to the one known good, hope that makes sense). Cleaned the carburators, stole the ignition unit from an 84 parts bike, it idles great, just won't rev up, dies when I try to give it some gas. The ignition unit from the 84 has different numbers than the one from the 83, guessing that may be my problem.

 

I saw on the forum a while back someone mentioning how to modify the wiring on an 84 to make it work on the 83, just can't find that thread. Anyone have any ideas for me?

[jrich]

OK, so I put the ignition unit from the 84 into the 83, and then did something recommended by a local motorcycle scrap yard, I put all the air box back in place (had not done that yet). Now it starts fine, and revs fine. Ye Ha!

 

Next steps, clean out the rust gas tank, get the air ride system charged up, make sure the clutch and brakes work, then I'm off on my first ride around the block. All things I should be able to do next week in the evening hours.

[luvmy40]

If I'm not mistaken, the '83 TCI is the red headed step child. The boost circuit 180 deg. out of phase as compared to the '84 and up units. or maybe the boost sensor just needs to be connected to the intake manifold rather than the #2 carburetor body.

 

You should be able to test this easily. Disconnect the vacuum line to the boost sensor from the carb/manifold and hook up a hand vac pump(MiteyMite). At idle, pull a slight vacuum and see if the RPM increase. On the '83 they will, if the boost sensor is good. Not sure what the results will be with the '84 TCI.

[Patch]

OK, so I put the ignition unit from the 84 into the 83, and then did something recommended by a local motorcycle scrap yard, I put all the air box back in place (had not done that yet). Now it starts fine, and revs fine. Ye Ha!

 

Next steps, clean out the rust gas tank, get the air ride system charged up, make sure the clutch and brakes work, then I'm off on my first ride around the block. All things I should be able to do next week in the evening hours.

 

First time working with Constant Velocity carbs hmmm;)

[bongobobny]

Yup!! The '83 uses vacuum for the advance from the carb as opposed to '84 on up using manifold vacuum, so the advance works backward. As mentioned, all you have to do is switch the boost sensor vacuum from the carb to the manifold and all will be well. Right now yes, the engine will start and rev just fine, but when you drive it and go to accelerate it will bog down and run like crap!!