Curseduth
XS400 Enthusiast
So I picked up two xs400s in a trade, a 1978 mostly complete and kinda running, and a 1980 parts bike with a crate of parts.
Previous owner said the 78 needed a battery and a carb cleaning. He replaced or repaired the stator and after this was done it just didnt run right.
I haven't been wrenching on a motorcycle in 15+years but am a fairly good mechanic. So on to the issue.
First after I got the bike home and got a little fresh gas in it and jumpers it to a small auto battery I was able to get it running, it obviously had synch issues with the carbs or timing as the left cylinder heated up quite rapidly vs the right cylinder. So I pulled the carbs and proceeded to clean them. I thought...they were stock carbs for the bike but after looking at them it was apparent there was a homemade bracket on the bottom and the top bracket was only held on by one side. (I can only assume they put the 1980 carbs on the 78).
So after cleaning I shoved them back on, checked for leaks, and turned it over...no fire. Plugs aren't great but they had weak spark so I figured it should at least attempt to fire. Then I noticed the right side was barely sparking regardless of coil change or plug. So I opened up the timing cover.
Very apparent someone had been working in there with a heavy hand. Hours later after trying to get the points set correctly I give up....
So long story short, is there a good write up for wiring in a TCI from a 1980 into a 78? All the schematics I see do not have the same colors I see on my tci box. Did I mention there is no fuse box on this thing and I cannot find where it used to be or where the PO hot wired what should have been fused. Also, is there much effort involved in putting slide carbs on(I was given two slide carbs that appear to be in good condition). Better to run a single Y cable or a dual cable?
I have spent hours trying to find a TCI swap with adequate pictures and the only thing I could find was either for the 650( which carries different colors and no identification of what is what on the box) or a simple "just swap the whole harness" answers.
Previous owner said the 78 needed a battery and a carb cleaning. He replaced or repaired the stator and after this was done it just didnt run right.
I haven't been wrenching on a motorcycle in 15+years but am a fairly good mechanic. So on to the issue.
First after I got the bike home and got a little fresh gas in it and jumpers it to a small auto battery I was able to get it running, it obviously had synch issues with the carbs or timing as the left cylinder heated up quite rapidly vs the right cylinder. So I pulled the carbs and proceeded to clean them. I thought...they were stock carbs for the bike but after looking at them it was apparent there was a homemade bracket on the bottom and the top bracket was only held on by one side. (I can only assume they put the 1980 carbs on the 78).
So after cleaning I shoved them back on, checked for leaks, and turned it over...no fire. Plugs aren't great but they had weak spark so I figured it should at least attempt to fire. Then I noticed the right side was barely sparking regardless of coil change or plug. So I opened up the timing cover.
Very apparent someone had been working in there with a heavy hand. Hours later after trying to get the points set correctly I give up....
So long story short, is there a good write up for wiring in a TCI from a 1980 into a 78? All the schematics I see do not have the same colors I see on my tci box. Did I mention there is no fuse box on this thing and I cannot find where it used to be or where the PO hot wired what should have been fused. Also, is there much effort involved in putting slide carbs on(I was given two slide carbs that appear to be in good condition). Better to run a single Y cable or a dual cable?
I have spent hours trying to find a TCI swap with adequate pictures and the only thing I could find was either for the 650( which carries different colors and no identification of what is what on the box) or a simple "just swap the whole harness" answers.
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