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Discussion Starter · #1 ·
The following applies to a 2010 Pitster Pro XJR SS with the 90cc Lifan motor with maybe 4 hours on it...



Lets start at the start. The bike fired up first kick after uncrating it an adding fuel. Serviced/setup/adjusted and handed over to the new owner. Long story short... the customer did not keep up on chain adjustments and the chain derailed... wadding up in the ignition cover and doing some damage. The chain bust through the ignition cover and broke the trigger coil off the backing plate. This is where the running issue started as far as i know.



So after getting off the phone with the Pitster parts department I was made aware that Pitster does not have engine related parts in stock for the XJR. So with that in mind I decided to pull the stator off my personal 70cc chinese motor to get the customers bike back in action. Instead of just swapping the stator and calling it a day, I pulled the ignition/lighting coils off the broken plate and reinstalled them on the good plate off my bike. That way all of the electrical components and connectors are OEM pitster on a new backing plate. HOWEVER, the trigger coil got schmucked... so I soldered in the trigger coil off the 70cc chinese stator plate. I ran the flywheel off the 70cc motor so it was matched with the trigger coil and stator plate as far as positioning.



At this point the bike fired back to life and idled. I gave it back to the owner after I got an ignition cover from a different vendor.



It showed up a few hours later with a running issue. After the engine warms up the bike bogs extremely bad. It will act like its running out of fuel and stall out when you let off the gas. The engine seems to get very hot for what it is. Logically one would start looking at electrical problems somewhere after considering the history of the machine.



Heres the kicker... turn the choke on and it runs like a dream.:confused:



Here is a rundown of things I have checked with no luck:

-Adjusted valves (intake was tight.. did not help)

-Swapped carbs with a known good off another XJR SS

-Swapped CDI boxes

-Unplugged Kill switch

-Adjusted fuel screw to 3 turns out

-Checked fuel line for kinks

-Checked gas cap/vent for vapor locking

-5 minute stare-down session with a small chinese cycle kicking my @$$

-Tried running the stock pitster flywheel

-Made sure the keyway wasn't bent or broken



The plug looks black? Has anybody experienced an electrical problem that clears up with more fuel/choke??



Just so it is known... the guys at pitster are going to warranty the stator by yanking one off a blown XJR SS motor that they have there. Not ideal... but at the same time they didn't HAVE to do anything about the situation so thats cool on their part.



Waiting on the stator from pitster... but I just dont see that being the fix from what I have been going through :banghead:
 

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Discussion Starter · #2 ·
Checked cam timing... spot on. Also installed the new stator from Pitster today with no luck.



I found that the paint had never been ground down on the frame where the coil mounts. Swapped a coil from a good bike/cleaned the ground tab up and it seemed to run good. Swapped the original coil back on and it continued to run good. Bolted the seat/plastics back on and its back to bogging mercilessly. I'm swapping the new coil back one more time before I throw my hands in the air. You can only swap out so many parts before there is nothing left to swap??



Anybody think the jetting needs to be changed for this particular bike even though its the same engine/carb thats on the other bikes and they run fine? All running the same carbs, same jets, same motor. All bone stock.
 

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Discussion Starter · #4 ·
I think I got it figured out... i hope. I drained the fuel into a ratio rite cup and although it wasn't old and rotten, it was extremely separated. Ethanol = Junk gas. The gas can that the customer filled the bike up with must have been sitting for quite a while...
 

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I've been mixing 1 oz. of Marvel Mystery Oil per gallon of Ultimate 93 octane, and it seems to stave off the artery-hardening abilities of the ethanol.
 

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Discussion Starter · #6 ·
I have a product called Startron that is designed specifically to deal with ethanol issues. I guess since the bike was brand new I didn't put much thought into bad fuel. Live and learn...





You would be suprised how lean that bike was running with that fuel in it BTW!
 
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