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The great fuel injected Roadie
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TOPIC: The great fuel injected Roadie
#674328
Gadgetman728 (User)
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Re:The great fuel injected Roadie 4 Years, 6 Months ago  
Thanks for the replies -
No warranty - but I do computer work for him and trade him shop labor. I just rode 60 miles on 55 mph roads to my house in Cheney. I put in clean plugs before I left. I also changed my tranny gear oil. Whew... it needed it. When the plugs are fresh the "dead zone" is much smaller and easy to ride/shift through.

When I got here, I looked on the web for reasons for carbon fouling.
1. driving too slow in too high a gear.
2. Too cold or too hot a plug for riding conditions.
3. Oxygen sensors.

I don't care about making my bike sound like a harley when I going slow. Yamaha engines like to drink fuel and accelerate. I ride in town in the lowest gear I can without rapping too high. I know if I dog it through town, I'm guaranteed fouled back plugs. the fronts are always spotless.

I pulled both my oxygen sensors awhile back, and they were both dirty, but the back one was dirtier. I used sensor cleaner and replaced.

The NGK spark plug site pointed out that Too Hot a plug was just as bad as too cold a plug. I'm running the hottest Iridium plug I could get, and now I'm thinking maybe it's TOO hot and not in the proper temp range.
Any thoughts on the matter.
 
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#674485
River (User)
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Re:The great fuel injected Roadie 4 Years, 6 Months ago  
When you get the problem worked out, please share the results with us.
 
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#674490
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Re:The great fuel injected Roadie 4 Years, 6 Months ago  
Gadgetman728 wrote:
The NGK spark plug site pointed out that Too Hot a plug was just as bad as too cold a plug. I'm running the hottest Iridium plug I could get, and now I'm thinking maybe it's TOO hot and not in the proper temp range.
Any thoughts on the matter.
If you are not running a highly modified motor, I think you should stay with the recommended spark plugs. I don't believe that has anything to do with your problem tho. There has to be something causing just the rear cylinder to foul the plugs.
 
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#674497
gilly (User)
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Re:The great fuel injected Roadie 4 Years, 6 Months ago  
Gadgetman728 wrote:
Thanks for the replies -
No warranty - but I do computer work for him and trade him shop labor. I just rode 60 miles on 55 mph roads to my house in Cheney. I put in clean plugs before I left. I also changed my tranny gear oil. Whew... it needed it. When the plugs are fresh the "dead zone" is much smaller and easy to ride/shift through.

When I got here, I looked on the web for reasons for carbon fouling.
1. driving too slow in too high a gear.
2. Too cold or too hot a plug for riding conditions.
3. Oxygen sensors.

I don't care about making my bike sound like a harley when I going slow. Yamaha engines like to drink fuel and accelerate. I ride in town in the lowest gear I can without rapping too high. I know if I dog it through town, I'm guaranteed fouled back plugs. the fronts are always spotless.

I pulled both my oxygen sensors awhile back, and they were both dirty, but the back one was dirtier. I used sensor cleaner and replaced.

The NGK spark plug site pointed out that Too Hot a plug was just as bad as too cold a plug. I'm running the hottest Iridium plug I could get, and now I'm thinking maybe it's TOO hot and not in the proper temp range.
Any thoughts on the matter.


If your front plug is burning fine then i don't believe it is a plug issue. It could be be the ECU is sending to much fuel to your rear injector, i don't know how to correct that on a Road star. I would say maybe you have a weak spark at that plug, but the bike would probably run rough. Could be a bad injector. A fuel processor could correct the issue but seems like it would just be a bandaid for a problem you might have.
 
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#674498
River (User)
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Re:The great fuel injected Roadie 4 Years, 6 Months ago  
blue_star wrote:
Gadgetman728 wrote:
The NGK spark plug site pointed out that Too Hot a plug was just as bad as too cold a plug. I'm running the hottest Iridium plug I could get, and now I'm thinking maybe it's TOO hot and not in the proper temp range.
Any thoughts on the matter.
If you are not running a highly modified motor, I think you should stay with the recommended spark plugs. I don't believe that has anything to do with your problem tho. There has to be something causing just the rear cylinder to foul the plugs.


+1
 
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#674507
texasscott1 (User)
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Re:The great fuel injected Roadie 4 Years, 6 Months ago  
+1 on installing the recommended sparkplugs. The FI system can handle #1 without a problem.

Once again the O2 sensors can be easily checked. They operate in a range of 0.0 to 1.0 volt. At idle it should be reading just above 1/2 volt - idle is a little rich but the sensor probably won't be hunting too much since the computer is ignoring the O2 sensors at idle. Up at cruise range the sensors will be moving above and below 0.47 volt as the mixture is constantly being changed. If the rear sensor is stuck at one low voltage reading then you've found your problem.

These are very good FI systems and easy to fix with the right tools and knowledge. One can probably fix it by throwing parts at the problem but it's a lot easier and less frustrating to make the correct diagnosis and replace the offending part the first time.
 
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My 99 Standard Test Mule
Scott B.
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#674543
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Re:The great fuel injected Roadie 4 Years, 6 Months ago  
Gadgetman728 wrote:
Thanks for the replies -
No warranty - but I do computer work for him and trade him shop labor. I just rode 60 miles on 55 mph roads to my house in Cheney. I put in clean plugs before I left. I also changed my tranny gear oil. Whew... it needed it. When the plugs are fresh the "dead zone" is much smaller and easy to ride/shift through.

When I got here, I looked on the web for reasons for carbon fouling.
1. driving too slow in too high a gear.
2. Too cold or too hot a plug for riding conditions.
3. Oxygen sensors.

I don't care about making my bike sound like a harley when I going slow. Yamaha engines like to drink fuel and accelerate. I ride in town in the lowest gear I can without rapping too high. I know if I dog it through town, I'm guaranteed fouled back plugs. the fronts are always spotless.

I pulled both my oxygen sensors awhile back, and they were both dirty, but the back one was dirtier. I used sensor cleaner and replaced.

The NGK spark plug site pointed out that Too Hot a plug was just as bad as too cold a plug. I'm running the hottest Iridium plug I could get, and now I'm thinking maybe it's TOO hot and not in the proper temp range.
Any thoughts on the matter.


On the Strats, there is mention of synching the throttle bodies, maybe it's an issue with the Roadies too?
any way, here's the article
http://www.linerwiki.com/index.php?title=ThrottleBodySynch
 
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#674548
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Re:The great fuel injected Roadie 4 Years, 6 Months ago  
Erbman02 wrote:
On the Strats, there is mention of synching the throttle bodies, maybe it's an issue with the Roadies too?
any way, here's the article
http://www.linerwiki.com/index.php?title=ThrottleBodySynch
How the hell are you supposed to synch a single throttle body?
 
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#674550
Erbman02 (User)
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Re:The great fuel injected Roadie 4 Years, 6 Months ago  
blue_star wrote:
Erbman02 wrote:
On the Strats, there is mention of synching the throttle bodies, maybe it's an issue with the Roadies too?
any way, here's the article
http://www.linerwiki.com/index.php?title=ThrottleBodySynch
How the hell are you supposed to synch a single throttle body?


Cut it in half? Didn't know there was 1 on the Roadie. Guess I'll need 2 42HSR carbs when I do my mod. lol
 
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#674553
texasscott1 (User)
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Re:The great fuel injected Roadie 4 Years, 6 Months ago  
The Strats are entirely different setups. Haven't read the book in a while but if I remember correctly they even use the O2 sensor during idle - no AIS.
 
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My 99 Standard Test Mule
Scott B.
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