2017-01-07 Fuel Injectors Matched - KrZy8

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dcarver

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2017-01-07 Fuel Injectors Matched







Awhile back, the baffle plates in the Aux tank broke and I repaired it using gas approved JB Weld. After a year or so, the plate broke free again. Unknown to me, the plate was rubbing against the JB Weld contaminating the fuel system with micro-particulate JB Weld matter.

In turn, the fuel injectors clogged and the bike ran crappy. We troubleshot everything but injectors. Changed plug wires, replaced one coil, then in desperation bought a used fuel rail from ebay and Voila! Fixed. That rail lasted for about 8 or 9 months then the crappy running started again.

Inspecting the injectors showed gray matter clogging the intake screen. Using a 9 volt battery, syringe and tubing, was able to clean the bulk of JB fro screen. Used an ultrasonic bath and to remove the rest. Yes, the screens can be removed using a self-tapping sheet metal screw but they are destroyed in process and I cold not source new screens.

While cleaning, a work mate sauntered by and said 'I used to engineer fuel injectors. Did you know that +/-10% is the acceptance criteria?'. Boom! Right then and there decided to have my spare 10 injectors cleaned and flow balanced. Here are the results.

I asked the company to choose the best matched set of 4 then the next best matched set of 4. One set is marginally better than the other. Both have excellent as-left flow numbers.



I like that they sent back the old parts. You can marginally see JB Weld deposits.



Here's a better picture.





I'm eager to get these balanced injectors installed on KrZy8. I need to pull the fuel rail anyway as I have a new to me airbox that needs be installed.



 
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