Join Date: Sep 2004
Location: Zephyrhills, FL - 25 miles NE of Tampa
Mileage, year, how long was it sitting since last start-up, and how long did the noise last?
Is yours gone in seconds after starting cold and most would call it a heavy knock?
Unfortunatly, on GL1800s a heavy startup knock at times is not unusual. Oil grade and type has little to do with it. I sometimes get that if mine sits for weeks, like 3 or more. It happens after truning off our motor, and the oil pump quit pumping, and the oil settles to the bottom of the motor, and the crank shaft drips "dry." On most motors, the crank shaft live in the bottom of the motor where the oil drips to, but on a GL1800 the the tranny lives there. You are probably hearing rod bearing noise, and it is gone in seconds after start up (less then 5 secs). On my different ones, I have tried the Honda Synthetic Blend, and it seemed more frequent then, but like Gary stated, I would have expected the oppisite. So, I am back to running Honda GN4 10/40. If you want to prevent it, ride it daily. Another way is to remove the FI/IGN FUES, and crank it for 30 secs before starting to get oil pumping after it has been sitting. The problem there is that sometime you may find it happening after only sitting for a couple of days. As for frequancy, any of mine might do it once a year in the climate here; I ride a least 340 days a year. It didn't seem to matter which kick stand I used.
JustWings - GL1800 Specialty Service and Repair