After Replace of TB cams, right side cylinder not firing;

[PNWrider]

I have replaced the original cracked TB cams on my ~70K 2011 R12RT with aftermarket aluminum cams.  Prior to the cam replacement, the bike was running well.  I have followed DR's throttle plate alignment advice; I have certified that the throttle cables are in place and moving the cams simultaneously,  

 

Upon completion of the cam swap out the right side cylinder is not firing.  The bike starts, runs roughly at part throttle, and dies immediately when the throttle is released.   I confirmed with a pyrometer that the right side exhaust is not heating up at all.  

 

I have done the following:

1. To determine if there the right side coil stick is bad, I swapped the right and left lower coil sticks: no change with  the right side still isn't firing. 

2. After returning the coil sticks to their original positions, I removed the right side spark plug, grounded it to the bike frame, and started the engine resulted in a fat, bright blue spark.  

 

I will get my loaned out GS911 back to try to get some diagnostic readouts. What engine diagnostic categories should I be looked for?  

 

How fragile are the wires going to the throttle body?  is it possible that I damaged the wire leads or the connectors upon disassembly / reassembly?  

 

Thanks,

 Bill Thompson 

[Hati]

1 hour ago, PNWrider said:

How fragile are the wires going to the throttle body?  is it possible that I damaged the wire leads or the connectors upon disassembly / reassembly?  

 

I'll jump in before DR does,  The cabling is no different to the rest of the bike's, make sure your plugs are pushed together properly until you can hear or feel a positive click from the locking tabs. Damage is always possible, but we can't see what you did or how competent of a mechanic you are ;)

 

Remove you right side injector and crank the bike to see if you get any fuel from it. My money is on the injector electrics at this stage. You ruled out the spark plug and coil. There is nothing else left. Your butterfly (air supply) works, your spark (ignition source) works so the last part of the combustion must be missing, the fuel.

[dirtrider]

11 hours ago, PNWrider said:

I have replaced the original cracked TB cams on my ~70K 2011 R12RT with aftermarket aluminum cams.  Prior to the cam replacement, the bike was running well.  I have followed DR's throttle plate alignment advice; I have certified that the throttle cables are in place and moving the cams simultaneously,  

 

Upon completion of the cam swap out the right side cylinder is not firing.  The bike starts, runs roughly at part throttle, and dies immediately when the throttle is released.   I confirmed with a pyrometer that the right side exhaust is not heating up at all.  

 

I have done the following:

1. To determine if there the right side coil stick is bad, I swapped the right and left lower coil sticks: no change with  the right side still isn't firing. 

2. After returning the coil sticks to their original positions, I removed the right side spark plug, grounded it to the bike frame, and started the engine resulted in a fat, bright blue spark.  

 

I will get my loaned out GS911 back to try to get some diagnostic readouts. What engine diagnostic categories should I be looked for?  

 

How fragile are the wires going to the throttle body?  is it possible that I damaged the wire leads or the connectors upon disassembly / reassembly?  

 

Thanks,

 Bill Thompson 

Morning  PNWrider

 

You didn't plug off the R/H side intake going into the cylinder head or into the air box to prevent dirt/junk entry then forget to remove the rag or wad of paper towel did you? (it happens)

 

If your intake passages are open then check that the R/H side is FULLY returning to the idle stop, not just opening & closing in tandem with the L/H side but actually hitting the idle stop screw.

 

Is the R/H throttle cable seated  properly under the retaining clip down in the cable seat?  They usually self-seat in OK but I suppose it could be possible that it isn't fully seated.  

 

I have had a couple over the years that throttle cable wasn't properly wrapped in the groove on the R/H throttle cam therefore holding the R/H throttle plate partially open at idle. Then massively tracking the R/H throttle plate opening ahead of the L/H side, the L/H side controls the fuel spray so if the R/H side tracks way ahead of the L/H side it gets way too much air in for the amount of fuel sprayed in (causes a basically dead cylinder).   

 

Otherwise verify the R/H side fuel injector is PROPERLY plugged in. If it is then put a NOID light on the injector connector for the R/H side then see if it is flashing on & off with the engine cranking and/or if possible while idling.   

 

I'm not sure a GS-911 will show you much other than the R/H side isn't firing, or the o2 sensor on that side isn't responding properly.  The GS-911 can't see air flow or fueling flow to that side. 

 

  

[PNWrider]

thanks Hati and DR for the suggestions on where to look for the solution.  Prior to my message yesterday, I was checking the TB cam movement by hand rather than sight and misjudged the actual motion of the RH TB cable.  

 

DR: "If your intake passages are open then check that the R/H side is FULLY returning to the idle stop, not just opening & closing in tandem with the L/H side but actually hitting the idle stop screw."

 

 After reading DR's reply, I did visually check the RH cam with an inspection mirror; the RH cam was not contacting the idle stop.  Opening the splitter box showed that the cables in the splitter box were routed correctly; the TB cable clip was also correct.  The problem was the RH outer sheath was not seated correctly on the splitter box exterior that is hidden behind the air horn.  Properly seating the outer sheath at the splitter box exterior resolved the problem. 

 

Thanks again.

Bill Thompson