Resistances and where to test them.....

[DaintyGrim]

Ok i am new new new to motorcycles and have an 1989 xs 850 as my first bike. Recently changed the clutch cable and plugs and am now having a nightmare of a time getting it to run. Went from running poorly to not starting at all. I am beyond a novice so when i read secondary and primary resistances i do not know where to test those. I am not a complete mechanical novice but mostly work on old VWs. I tested my resistance on the coil alone and read 2.5, coil through wire 12.9 and coil through plug 18.55. I do not know if these are good but they seem to be fairly consistent in all 3.

Also may have swapped 2 coil plugs so of anyone off the top of their head knows which coil wire goes to the center coil would love to hear it lol (white or yellow).

 

[gggGary]

Should be yellow to the middle.

All three get a red white,

then orange, yellow, gray to the other coil terminals

I think orange is right, gray left

 

[DaintyGrim]

Should be yellow to the middle.

All three get a red white,

then orange, yellow, gray to the other coil terminals

I think orange is right, gray left

Thank you! How about the resistances? Those in spec?

 

[gggGary]

2.4 sounds right for the primary
If the secondary are K ohms ie 12.9K ohms that sounds right also.
Check that you're getting 12 volts on the red whites with kill switch in the middle position.
XS850 fuse boxes are just as notorious for bad connections as all other Yamahas of that era.
Use a light bulb tester and check both sides of every fuse for twelve volts.

 

[DaintyGrim]

2.4 sounds right for the primary
If the secondary are K ohms ie 12.9K ohms that sounds right also.
Check that you're getting 12 volts on the red whites with kill switch in the middle position.
XS850 fuse boxes are just as notorious for bad connections as all other Yamahas of that era.
Use a light bulb tester and check both sides of every fuse for twelve volts.

Getting 11 voltsish. Seems to be roughly 1 volt off of what i get at the battery, if i use a charger or jumper i can have 14 at battery and 13 at the coil.

Checked fuzes they were all just twisted wire and electronical tape. Soldered then all together and checked fuzes shoukd be gtg. I am getting spark but it looks anemic, i can barely see that it's sparking.

 

[gggGary]

Getting 11 voltsish. Seems to be roughly 1 volt off of what i get at the battery, if i use a charger or jumper i can have 14 at battery and 13 at the coil.

That's about right.
Check all your ground connections, wires and also connector blocks especially the one to the TCI ignition module and pick ups, open, clean, lube, reassemble.
Does it crank over strongly?

 

[DaintyGrim]

Cranked over, started and ran but would lose power when i tried to accelerate. Now it still turns over strongly but isnt firing. Idk whats going on but seems to be terring worse.

 

[gggGary]

Put the petcock on prime?

 

[DaintyGrim]

No vacuum lined gas all gravity fed, bowls are full.... getting heavily discouraged

 

[gggGary]

couple shots of carb cleaner in the intakes, will it fire?

 

[gggGary]

valves checked, set. compression?

 

[DaintyGrim]

will try the carb cleaner in the AM, compression checked i believe it was around 140