Plug Swap and Throttle Body Sync

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Bounce

Chicks Dig Scars
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Swapped plugs and did a throttle body synch on the FJR today. During the tear-down phase, I found the T-Bar covered with black scuff marks. My guess is that the shop that did the valve clearance check used a rubber mallet during reassembly. This was cleaned up with elbow grease and the liberal use of Nev-R-Dul; chemically-impregnated cotton batting. I had a can laying around unused from the days when I had silver rims (aluminum) on my Wing. Since getting the Feejer I've not had to worry about brake dust, road grime, and the rims pitting thanks to their black finish.

Plugs:

plugs12k.jpg


OEM Plugs @ 12,000 miles

The last time I did a plug swap was when I first went to iridium (NGK CR8EIX) back at 12k miles.

The iridiums don't provide any real performance boost but they do extend the service interval beyond the OEM 8k mile recommendation for plain old plugs (POPs).

Back when people started first talking about iridium they suggested that, perhaps, doubling the service interval might be possible. Without any concrete, lab-based evidence, all I can say is that I think I've been experiencing some degradation in mpg recently. To me that's one clue that it's time for a tune up. With the bike now at 28,078 miles, it was time (16,078 miles on the iridium plugs). The condition of plugs is fine and, IMO, justifies the difference in price for the iridiums over the POPs.

plugs-28k.jpg


NGK Iridium Plugs @ 28,078 miles

The color and construction of the iridium plugs looks good. Any appearance of center posts missing or shortened is a trick of the camera angle. With EFI and it's ability to compensate for a multitude of sins, reading plugs is no longer a universal diagnostic tool. If there is serious fouling, oiling or other problem, it should show up. But it's use as an indicator of "good health" can be misleading. A few landmarks about the photo are worth mentioning. The dark areas on the insulators are greasy fingerprints; not something wrong with the insulators. The "gunk" around the top of the threads is anti-seize (silver). You can see more of it in the threads. Over enthusiastic application when these plugs were installed didn't appear to affect performance. During this service, I used copper anti-seize and used it much more sparingly. I would recommend the use of some kind of anti-seize due to the extended service intervals involved.

Throttle Body Sync:

The throttle bodies were within spec. If a shop were asked to check them, they'd probably have not done anything. I tickled the sync to get them closer. They might have drifted a little bit, but not much, since the last time they were done. A little patience resulted in them being much closer.

Fuel Consumption:

Given that local fuel is all oxygenated, these numbers can be artificially low compared to what the bike can get when out on the open road. I'll be checking my mpg over the next few weeks, but prior to the swap, my most recent numbers were:

- 41 mpg: While riding with a guy on his Daytona 600

- 43.7 mpg: Out on a GWRRA Chapter ride where they did about -20 of any posted limit (this is where I thought I should be getting high 40's to low 50's)

- 40.6 mpg: While riding with a guy on his Daytona 600 on the way back from that same GWRRA ride (closer to the speed limit with a pass at Tx51) and some commuting. I've been getting in the mid to upper 30's when strictly commuting.

 
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Which TBS tool do you use? Is it one of those add-mercury types?I don't have one yet but need one fairly ASAP as riding season draws near.
I have the Motion Pro economy model of mercury sticks.

https://www.motionpro.com/motorcycle/tools/...omy_carb_tuner/

I got mine from JC Whitney but couldn't find a reference there when I just went to look. At the time it was something like $20 for the whole thing. I suspect the price hike is related to the whole, "Woe is me. Mercury is bad. Where's my hat? Boy am I mad! [waaa] [waaa] [booo] [hoo]!" <_<

 
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You can get the syncro set up from Sportbike Effects,(he's a member here) plus a number of other goodies ta boot :D

:jester:

 
Is it a bad pic or does the irridium plug on the left have a broken electrode?

My FJR:

12,488 FI Synch/Disconnect O2 sensor

15,140 Spark Plugs and Air Filter

Between 34,000-35,000 now.

Better put some more plugs in. MPG is dropping.

Hi Mark!!!!

 
Try sentence # 2

"Any appearance of center posts missing or shortened is a trick of the camera angle."

So. I'm guessing that it is just a bad pick.

 
Which TBS tool do you use? Is it one of those add-mercury types?I don't have one yet but need one fairly ASAP as riding season draws near.
I have the Motion Pro economy model of mercury sticks.

https://www.motionpro.com/motorcycle/tools/...omy_carb_tuner/

I got mine from JC Whitney but couldn't find a reference there when I just went to look. At the time it was something like $20 for the whole thing. I suspect the price hike is related to the whole, "Woe is me. Mercury is bad. Where's my hat? Boy am I mad! [waaa] [waaa] [booo] [hoo]!" <_<
Thanks. Yeah, I used to have something similar years ago called Carb Stix. Looks to be about the same.

I've seen the Motion Pro Economy listed on several on-line sites for about $65 now.

I'll probably go that route.
 
Try sentence # 2"Any appearance of center posts missing or shortened is a trick of the camera angle."

So.  I'm guessing that it is just a bad pick.
Not a bad pick. Just a bad angle on that one plug due to the way I lined the plugs up in pairs.

 
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Bounce, I don't think the mileage you're getting is particularly low. Seems you're averaging around 40mpg, which I think is normal if you actually use the throttle once in awhile. You could prolly get better with more restraint, but what's the point then of having such a powerful motor?

Those Iridiums look nice for 16K+ miles. I've got a set ready to go in soon. Thanks for posting the pics! :)

 
(Appearance) is what I was thinking, too. Up until now the discussion about the iridium on the FJR was "should hold up" to extended service intervals. This proved it to me.

 
(Appearance) is what I was thinking, too. Up until now the discussion about the iridium on the FJR was "should hold up" to extended service intervals. This proved it to me.
whats the part number on these plugs????

Richard

Nevermind I found it.

 
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Why would the wrench at the shop need to take a rubber mallet to your T-bar? Mine just slides right in.

 

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