Honda Shadow 750: When driving the speedometer will shut off along with the digital mile counter. At low speeds it will also sputter when this happens

I am no Honda expert, but a similar problem happened to my ex sister in-laws Ford Taurus. The speed odometer would jump around and it had trouble shifting (automatic transmission). After driving it I changed out the speed odometer sensor on the transmission and it's been fine ever since. I changed out the sensor because if the cars computer cannot tell how fast the car is traveling then fail safes in place go into effect and the computer will do it's best to keep the cars rpm's down based on the speed indicator and not let it shift or shift properly either. If it's getting false speeds then it will shut down the motor when the speed gets to high and allow it to run as the speeds fall (jumping speed odometer needle). It effects the transmission shift points also. It will either shift erratically or not shift out of say 2nd gear, so that the cars engine can't get damaged based on what signal the speed sensor is sending the computer.

Put a spike air filter on my 06 honda shadow spirit 750cc and now it spits and sputters won't go past 35 with out spitting and sputtering

I'm trying to replace the sensor and cable since my speed ometer is not working

charging device or voltage regulator is faulty.

Sounds like a grounding problem. I know not easy to fix. To start with, I suggest running another ground wire (just a jumper wire with alligator clips on each end) from the instruments to the frame and see if the problem goes away then if fixes make the repair perminent. Best wishes.

Sounds like low voltage. Ck charging system.

how's the battery on the bike? weak battery - speedometer won't work correctly. had the same prob with my 04 750. replace battery