Hey all,

Just joined the forum and I cant stop reading about restores and repairs.  I got my first K100 about a year ago and it was a silly mess, fairing all cracked and falling apart so I removed them and am in the process of a Franken'bike. 
I purchased the bike to teach myself how to work the engine as i hear its a joy to. It is now ride-able and i commute regularly with it. but I feel like there is always something that needs to be fixed....suspicious hall effect sensor issue or MAF. Poor power, running super rich with sooty black spark plugs.

any tips/advice for working on it would be much appreciated but for now ive been reading my clymer book

Alex

WelCome to the Knuthaus...

Hi Alex. WelKome to the forum. Glad to hear you are enjoying the K-Bike. They are a dream in all respects.
Best if you put a post up in the technical/repair section regarding your problem as many don't read the intros.
But to get you started, if all your sooty plugs are the same, then it'll be easy to track down.

1. Could be the fuel pressure regulator (FPR). Check to see if you are getting a good flow on the return hose. Or, open the tank and listen for the gush as it returns. Little or no return means your FPR needs replacing.
   
2. Fuel Injection Control Unit (FICU) could be getting wrong signals from one of the sensors like the Mass Air Flow (MAF) sensor or the temperature sensor, the later being more likely. If the sensor goes 'open circuit' due to corrosion (very common) then the FICU thinks its in start mode and its really very cold and so pump a shit load of fuel in. Pull the plug on the FICU and test Ω between pin #10 and #13. At ambient temp it should be ≈2.5kΩ. There are instructions on the Trouble shooting link off the Portal page.
   

Cheers

Welcome, before you get too deep into HES or MAF issues do the simple stuff like checking the TB rubbers and crank case breather pipe for cracks. Good luck with it.

Welcome Alex,

Post up a few details of what your bike was before you started the transformation (model, VIN, year etc.) - it'll help with diagnosis etc.

Nice place McLean VA - lived there for about 2 years (2008 - 2010) and my kids went to Franklin Sherman Elementary School. Happy memories! Unfortunately, I didn't discover K100's until after I returned home to the UK - there is some cracking riding on your doorstep. 

Enjoy!