White screw- throttle body synchronization

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thefix

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I can say from experience. You have clogged injector(s). The bike should idle smoothest with sync screws closed more because the idle sync screws affects mixture making it richer. And the only pour in the tank cleaner that might work is Yamaha “ring free”. Option 2- Removing the injectors and a “proper cleaning”. Seafoam= joke , mainly a carbon remover by being difficult to burn, it has no solvents. Fyi- morgan carbtune’s hoses are WRONG size for FJR. The hoses should be 5/32. Take the 3/16 and put an adapter to 5/32. Also confirm the sync caps are not loose or cracked. I use silicone caps. Fact: TB#3 was set at the factory for proper emissions.
 
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Pjotr

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Thxs for your input. On the white dot on cil#1 on gen 3 (2013) see earlier in thread.

You mention proper cleaning of injectors; any recommendations how to do that?
 

RossKean

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If injectors are dirty, RingFree or other injector cleaner MIGHT help but better to get them done by a company that specializes in cleaning fuel injectors. For a reasonable cost, they will clean the injectors ultrasonically while rapidly actuating them and pumping solvent through. They will replace the inlet filter baskets and evaluate the injectors with respect to flow and spray pattern. If one or more is off badly, you may need to replace it. Sets of used FJR injectors often come up on ebay.

There can certainly be other causes but injectors are a distinct possibility. I would probably try opening up the base screw and trying the TBS again before messing with injectors. Doesn't take much time and costs nothing.
 

Pjotr

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If injectors are dirty, RingFree or other injector cleaner MIGHT help but better to get them done by a company that specializes in cleaning fuel injectors. For a reasonable cost, they will clean the injectors ultrasonically while rapidly actuating them and pumping solvent through. They will replace the inlet filter baskets and evaluate the injectors with respect to flow and spray pattern. If one or more is off badly, you may need to replace it. Sets of used FJR injectors often come up on ebay.

There can certainly be other causes but injectors are a distinct possibility. I would probably try opening up the base screw and trying the TBS again before messing with injectors. Doesn't take much time and costs nothing.
Unlike gen 1 and 2, Gen 3 has no base screw as far as I know.
 

thefix

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Removing the injectors is simple but i think there are 2 large phillips looking screws requires JIS (japenese industrial screwdriver ). Otherwise you’ll buggger them up. That holds the rail in place. It takes patience. Dont be in a hurry to remove the whole “fueling rack”. There are a few hoses. Take pictures before you turn the 1st screw. You must remove the injectors from fuel rail. Get new orange o-rings . And get silicone grease( silglide) for orings. Fyi… i am speaking of gen2. Gen3 should be very much similar .
 
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Pjotr

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Unlike gen 1 and 2, Gen 3 has no base screw as far as I kn
Base screw meaning the paint dot one. No marking on any Gen II screws.
Rosskean,
I now have looked at the self diagnostic, once you know it looks very simple. I have a diagnostic code 67, with value 02; meaning it is necessary to erase the ISC (idle speed control) learning data.
it also states how to do that.
what I don’t understand is the cause for such a code. why doesn’t it always “self learn”. This is not adressed anywhere in the manual as far as I know, or on internet.
 

RossKean

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Rosskean,
I now have looked at the self diagnostic, once you know it looks very simple. I have a diagnostic code 67, with value 02; meaning it is necessary to erase the ISC (idle speed control) learning data.
it also states how to do that.
what I don’t understand is the cause for such a code. why doesn’t it always “self learn”. This is not adressed anywhere in the manual as far as I know, or on internet.
Sorry, I don't know much about that stuff for a Gen III+
 

Pjotr

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Sorry, I don't know much about that stuff for a Gen III+
No problem😎, I reset it and get now the code 01, no further action needed. But i still like to think it should run more balanced.

nSo now time for perhaps a stupid question, but cannot find answer. I took out the ignition coil and spark plug. The topside of the spark plug looks like on the photograph just the thread, unlike on the picture on the box that shows for me the more known configuration. If I look into the coil it looks like the diameter is bigger than the diameter of the thread on the spark plug. In other words I wonder if connection is electrically sound. Do you need to put something on top of the spark plug on the thread?
 

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escapefjrtist

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<<snip>> nSo now time for perhaps a stupid question, but cannot find answer. I took out the ignition coil and spark plug. The topside of the spark plug looks like on the photograph just the thread, unlike on the picture on the box that shows for me the more known configuration. If I look into the coil it looks like the diameter is bigger than the diameter of the thread on the spark plug. In other words I wonder if connection is electrically sound. Do you need to put something on top of the spark plug on the thread?
On my '15 and other GEN IIIs I'm familiar with, the screw on adapter is removed on the spark plugs. When installing coils you'll feel (and hear) the sound of the coil going over the threaded portion of plug. You have to forcefully push downward to fully seat the coil.

~G
 

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