Honda Motorcycles - FireBlades.org banner

1 - 13 of 13 Posts

·
Registered
Joined
·
18 Posts
Discussion Starter #1
hey guys, i know im in the wrong section but i need some help quickly, my customer is coming to pick the bike up this friday! I'am working on a 2002 honda hornet 919 for a customer and the bike ran perfect until i put the new headlight housing and headlight on yesterday. Now it just backfires when i try to start it, i hook a charger up to help it turn over better but it still just backfires every few seconds. so i unplugged everything but the main wires, the ones that control the starting and kill switch but that didnt help, i noticed 2 fuses were blown so i replaced those and that didnt help. The wires are really bunched up in the housing so i was wondering if something got shorted and possible burned out the icm or something of that nature. any help would be greatly appreciated.
 

·
Super Moderator
Joined
·
32,034 Posts
hey guys, i know im in the wrong section but i need some help quickly, my customer is coming to pick the bike up this friday! I'am working on a 2002 honda hornet 919 for a customer and the bike ran perfect until i put the new headlight housing and headlight on yesterday. Now it just backfires when i try to start it, i hook a charger up to help it turn over better but it still just backfires every few seconds. so i unplugged everything but the main wires, the ones that control the starting and kill switch but that didnt help, i noticed 2 fuses were blown so i replaced those and that didnt help. The wires are really bunched up in the housing so i was wondering if something got shorted and possible burned out the icm or something of that nature. any help would be greatly appreciated.

No MIL flashing on the dash?
Bad kill switch perhaps.
 

·
Registered
Joined
·
18 Posts
Discussion Starter #3
no, i dont have the dash for the bike yet, just wierd that it run perfect until i run the wires through the headlight housing and connected the headlight and then the bike just backfires while im trying to start it, it will not run, just backfires badly, the kill switch seems fine.
 

·
Super Moderator
Joined
·
32,034 Posts
no, i dont have the dash for the bike yet, just wierd that it run perfect until i run the wires through the headlight housing and connected the headlight and then the bike just backfires while im trying to start it, it will not run, just backfires badly, the kill switch seems fine.

Does it still backfire if you jump the starter solenoid instead of using the starter button?
I assume the fuel pump is running?
 

·
Registered
Joined
·
18 Posts
Discussion Starter #5
i Haven't jump the starter solenoid, i dont think that would make a difference or would it? and yes the fuel pump is working, when i turn the key switch on it comes on for about 2-3 secs then cuts off, just like it always has, and the headlight, horn, turn signals work properly. could the spark plugs have gotted fouled somehow when i tried to start the bike after i installed the headlight?
 

·
Registered
Joined
·
18 Posts
Discussion Starter #6
UPDATE! I removed and cleaned the spark plugs, put them back in and got the bike to run, it still backfires badly and it is definetly not running on all cylinders, I wonder if a new set of plugs would fix the problem, if so, how much are a set of plugs for the 919?
 

·
Registered
Joined
·
321 Posts
1.Try unplugging the batter and giving enough time for the ECM to reset. My bike did that once and I unplugged everything and then it started back up fine.

2.Also double check that the fuel pump isn't turned off/has gas.

3.and if you haven't tried opening up the gas tank, try opening it up because the engine could be vapor locked. My buddies R1 used to do that on me all the time and it was freaking annoying. I would be riding and then the bike would backfire badly and then shut off on me. When there is too much pressure in the fuel system, it wouldn't run properly. easy solution is to just open up the gas cover for a few minutes and start the bike
 

·
Registered
Joined
·
18 Posts
Discussion Starter #8
1. already did that, made no difference
2. fuel pump is working/has gas
3. i opened the tank lid and it didn't help while trying to start.

I told my customer the problem and she is going to purchase new spark plugs, so should have those in a few days, hoping that will fix the problem!
 

·
Super Moderator
Joined
·
32,034 Posts
1. already did that, made no difference
2. fuel pump is working/has gas
3. i opened the tank lid and it didn't help while trying to start.

I told my customer the problem and she is going to purchase new spark plugs, so should have those in a few days, hoping that will fix the problem!

Might be worth checking the fuel pressure regulator while you're under the tank - pull the vacuum hose, switch on the ignition to prime the fuel pump, make sure no fuel comes out of the FPR.
 

·
Registered
Joined
·
1,173 Posts
Is the dash, signals, new headlight all working when you turn the key?
 

·
Registered
Joined
·
321 Posts
At this point, i would ask the customer for any pre-existing conditions from the bike. Sometimes people jimmyrig wires in their bike to make it run so when you replaced something, you took out what ever was there.

If it wasnt the spark plugs, the only thing i can honestly suggest is check the battery/stator/rectifier. In somecases, the battery could have enough power to start the bike but there isnt enough power going through the ignition pulse generator.

Im going through my 954 shop manual (idk if it may apply to the hornet too but) it says it may be caused due to peak voltage is lower than standard with the probably cause being 1.Cranking speed to low (battery under charged)
2. Faulty ECM

might be time to break out the 919 shop manual
 

·
Registered
Joined
·
1,173 Posts
Have you checked battery voltage or tried jumping her?
 

·
Registered
Joined
·
18 Posts
Discussion Starter #13
yes all the headlights, tail lights and turn signals work perfectly, it has a new $90 battery, is about 2 months old, so that is new to me, i have been using a battery charger while trying to start the bike so i won't run the battery weak or dead, i'm just waiting on the new spark plugs and i'm hoping through some wierd way, the plugs will fix the problem.:idunno:
 
1 - 13 of 13 Posts
Top