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bike miss firing

brianfisk

New member
Let me start with some history. I broke down last summer, the bike started misfiring,and then stopped. it was the HES. Got it replaced and it ran fine for a few miles. Then started misfiring again. It was thought to be water in the gas. I rode for 2200, each tank of gas it got better and I was able to run the tank almost dry.
I have since changed the fuel filter and cleaned the tank. I left for Bike week in the cold (13). It ran fine until it warmed up around (55). Which was over500 miles. Then a few misses. Continued getting worse, would run awhile when cold. I decide that I did not need to break down in the boonies so I headed home. It kept getting worse, almost all the time.
I stopped in a rest area to let it cool off . I also for some reason decided to pull all the relays in the fuse box. 800 miles later it still has not missed once and actually started a bit easier.

Any ideas? I want to fix this and don't know what to do. I think it it an electric problem.
 
Rule of thumb

Start with fresh plugs and then the wires if they are original.

Lawnmower, chainsaw, family car, start with plugs.

Wires are easy. In the dark, spray water on them. If they are an issue, you should see the discharge. It's actually neat to see.
 
Lawnmower, chainsaw, family car, start with plugs.

Wires are easy. In the dark, spray water on them. If they are an issue, you should see the discharge. It's actually neat to see.

Most of the time yes, but leakage is not always visible.

At that mileage, it's not a bad idea to replace them if for nothing but PM.
 
plugs&wires

The plugs were replaced at the time of tune up. Wires were done 20,000 miles or so before. Since Both sides were not firing I ruled them out. Plus the fact that the relays were pulled and bike ran right. That is the direction I believe that I should lean towards. I also mentioned that the bike starts better now.

Brian
 
.. I stopped in a rest area to let it cool off . I also for some reason decided to pull all the relays in the fuse box. 800 miles later it still has not missed once and actually started a bit easier...

My '02 R1150RT abruptly stalled and died several times over a 3 year period. When looking at the relays (in desperation) I noticed that one was standing a bit proud of the others, the Motronic Relay. After I pushed it down the bike started and ran fine again.
I cannot explain it, and none of my guru friends ever heard of such a problem. But it happened at least 3 times to me.
As superstitious preventive, I put a chunk of styrofoam between relay tops and relay box cover for a couple of years. Since then I've discarded it and the problem has not recurred.
My bike had seen a lot of rough roads, that vibration is the only thing I can think of.
Superstition or not, it doesn't hurt to push the relays down when you're stalled at the roadside.
 
The plugs were replaced at the time of tune up. Wires were done 20,000 miles or so before. Since Both sides were not firing I ruled them out. Plus the fact that the relays were pulled and bike ran right. That is the direction I believe that I should lean towards. I also mentioned that the bike starts better now.

Brian

Just a quick check. What coding plug is installed in your electrical box? Coding plug is positioned, mid box called Relay 1 below. On your bike it should be Yellow and connect pins 30 and 87.

Do you have any other add-ons, for instance a Powercommander, Techlusion or BoosterPlug?
RB

r11fuseb.gif
 
My '02 R1150RT abruptly stalled and died several times over a 3 year period. When looking at the relays (in desperation) I noticed that one was standing a bit proud of the others, the Motronic Relay. After I pushed it down the bike started and ran fine again.
I cannot explain it, and none of my guru friends ever heard of such a problem. But it happened at least 3 times to me.
As superstitious preventive, I put a chunk of styrofoam between relay tops and relay box cover for a couple of years. Since then I've discarded it and the problem has not recurred.
My bike had seen a lot of rough roads, that vibration is the only thing I can think of.
Superstition or not, it doesn't hurt to push the relays down when you're stalled at the roadside.

Hey I like this answer! I am going to try pulling it out a bit and see if I can get it to repeat the problem I had.




Also thanks for the diagram on the fuse/relay box.

Brian
 
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