Trying to figure out crappy gas mileage

[Olie]

So I took the bike to the garage and started tearing her apart to see why I'm only getting 30 MPG. Its obvious the previous owner had something done as all fuel lines and throttle cables are labeled with tape. What really blows my mind is when I pulled the spark plugs the gap was so small I couldn't get the gauge under it. Pulling the needles now from the carbs but I'm afraid to see what's in there. Anyone else heard of a gap smaller than .020?

[Olie]

So I pulled the carb tops off and found something I've never seen before. The spark plugs didn't look fouled but the gap was ridiculously small and the diaphragm edges had some weird white gunk on it. I fould in on the carb where the edge of the diaphragm sits. The inside of the carbs were OK but it looks like they need to be pulled and cleaned properly. Anyone know what this is from? Bike only has 1200 miles on it.



I did shim the needles with two shims equaling 1mm, pulled the snorkel and put a K&N replacement filter in. (It didn't want to fit).

During the first start-up, she started right up without choke. I let her warm up and went for a ride. I like the sound without the snorkel. Power seemed more even throughout the RPMs with no surging or lags. The bike seemed to run decently prior to all of this but I couldn't understand why I was getting 29/30 MPG. So my guess is, with all the cables and hoses being labeled by previous owner that the carbs have been pulled and the jets changed. With the shims in now and the plugs gaped correctly I am hoping to see some improvement until I can pulled the carbs and go through them correctly.

[Motofool]

Originally Posted by Olie

So I took the bike to the garage and started tearing her apart to see why I'm only getting 30 MPG...........What really blows my mind is when I pulled the spark plugs the gap was so small I couldn't get the gauge under it.......

I don't believe that the reduced gap has been the source of your problem.

Check for small but steady fuel leak from the carbs up, including the float valves with the engine running (vibration tends to make old valves leak and allow a higher level or even overflow of the carbs' bowls.

[Olie]

Originally Posted by Motofool

I don't believe that the reduced gap has been the source of your problem.

Check for small but steady fuel leak from the carbs up, including the float valves with the engine running (vibration tends to make old valves leak and allow a higher level or even overflow of the carbs' bowls.

So where is it going? No pooling or puddles under the bike. Crankcase isn't full of gas at oil change. I guess we'll see at next fill up.

[Motofool]

Originally Posted by Olie

So where is it going? No pooling or puddles under the bike........

Into the atmosphere.

Small and steady leak = evaporation

This could be your problem:
https://www.ninjette.org/forums/showthread.php?t=176462

[Olie]

She ran well this morning, little choke needed at start up. Let her warm up and checked for leaks, luckily none were found. I think it's the floats as now the oil fill cap smells like fuel. So, looks like a carb removal and tear down is next. I miss fuel injection....