[CEEZZ]

so a few of you might recall that i took my 1986 1100 honda shadow to a local known shop to help with my bike.so after some testing and using someone else's cdi box,i got my bike started again.my bike was purchased somewhat running,but sometimes it just wouldn't run,it had no spark,sometimes it would have spark and run great.i could turn it on and let it idle for 30 to 40 minutes,and it would run great,but if i took it on a ride for lets say,10 to 15 miles,i would loose power to rear cylinder,but still make it home.so finally it just would not start.SO guy at shop put in a cdi box that he had and bike started right.i rode the bike home,15 miles one way.i pulled over for some gas,put another 20 miles on it around town.so i decided bike is up and running,so i took it to work,just cruised on the freeway about 75 mph,after doing 20 miles,lost spark to rear cylinder again.i made it to work,it cooled off,got on it after work,it sounded great,rode it half ways home and it did it again.i quickly got home,let the bike run and idle on one cylinder,pulled the seats off and checked to make sure that there was power to coils and there was.the blinked rapidly with the test light on it,and the black with white stripe stayed on,those are for the rear,i checked the front wires,blue blinked rapidly and the black with white stripe stayed on.so i thought maybe coil is bad.i swapped the coils around,rode the bike just long enough to to cause the same issue and it did it again,but still only in the rear cylinder.
so my question is,could the plug wires be bad?i did put in four new plugs,but not wires.but could both the wires go bad when the warm up and return to running condition when it cools off
i could understand one wire,but both?

sorry for long post,but tried to post everything i could think of.thanks in advance

 

[smilie]

bad pulse generator.

 

[CEEZZ]

I looked on eBay but didn't see any,does any one know where I can get one?

 

[CEEZZ]

does any body know if other years will work?has any body tried this and if so,how?

 

[CEEZZ]

Anybody?

 

[Scared]

Are you sure it is not getting spark? Have you checked the spark? I don't know if your bike is dual carbed or not, but the carb for the rear cylinder could be giving you the problem. Maybe a stuck float or trash in the needle. Just putting it out there. I've not worked on a shadow that old so I could be way off.

 

[CEEZZ]

I'm pretty sure it's the spark because if I pull out a plug it's pretty wet so I'm sure there's fuel,and also when it does stop working,I let it ilde and pull off a rear plug wire,plug in another spark if and ground it out and nothing happens,like there's no spark

 

[Scared]

I'm pretty sure it's the spark because if I pull out a plug it's pretty wet so I'm sure there's fuel,and also when it does stop working,I let it ilde and pull off a rear plug wire,plug in another spark if and ground it out and nothing happens,like there's no spark

Gotcha. Just making sure.

 

[TylerLew89]

Check to make sure you have spark. Very easy test. How old are the plugs?

 

[CEEZZ]

The plugs are brand new,had this issue before so I replaced plugs but it's still doing it after a good 20 minute ride

 

[TylerLew89]

Next step is your pulse generators. Although, I have no experience with them failing. I do know you can measure the resistance from each. I'd say so this cold then do it when the rear cylinder begins to fail. If there's a major difference you found your answer

 

[CEEZZ]

Yea I'm going to have to do that next.

It's wierd because I can let the bike ilde for 40 minutes and it's great,but if I ride it at 75mph for 20 to 30 minutes it acts up

 

[TylerLew89]

I am just spitballing here.

Could there be something wrong with rear cylinder which causes it to die after warming up? Perhaps there's some bad expansion going on inside the chamber and it causes the piston to seize? Can you verify if in fact the cylinder is moving after it doesnt fire?

 

[CEEZZ]

Yes cylinder continues to move after the spark dies out,I should have time today to test out pulse generator and see what readings that's giving me

 

[CEEZZ]

Just wondering,would the spark plug wire make it do that?

 

[Eagle7840]

Just wondering,would the spark plug wire make it do that?

Usually when a plug wire is bad, it's bad. But heat does do some weird things. Are you positively sure the primary coil wires are firmly seated into the blade terminal on the coils? I had a similar problem with my 96 Shadow and traced it down to the primary coil wire for the rear cylinder plugs. The coil connection blade was seated between the boot and connector and not seated into the female wire connector. Sometimes it would run great for several days and then poof I'm running only on one jug. If the primary wire is properly connected to the coil, there shouldn't be any flex at the boot connection.

 

[CEEZZ]

On my coils,the primary appears to be soldered,I cannot remove them,so I don't think that's the issue but I'll double check

 

[Eagle7840]

On my coils,the primary appears to be soldered,I cannot remove them,so I don't think that's the issue but I'll double check

Factory connections are plug in, not soldered. I just checked my manual that covers 85-96 1100 Shadow. It's possible that the one of the previous owners soldered on the primary connections to the coils hoping to fix the problem you're now experiencing. If not soldered properly you might have a cold solder or cracked joint causing intermittent contact. That would explain why it runs fine at idle but as engine heat increases the fractured solder joint opens causing failure.

 

[CEEZZ]

You know I fully understand that,but Ive swapped the front coil to the back and the back to the front and it still does it only in the rear

 

[Ebacon]

I had the same problem. Long story short it was the ICM boxes. It only happens on the highway. I'm betting you put on s faulty used icm.