Spark Knock

[dnifong]

Can the LT spark knock?
Does it have a knock sensor that will retard the timing automatically if there is a knock present?

If not can the timing be adjusted?

thanks,
dale

[Steve_R]

Everything is controlled by the Motronic (computer) on the bike. There is NO timing adjustment.

[dnifong]

OK,

what would be the probable cause of spark knock sound?

[Steve_R]

Riding to low in the bike power band and trying to ride it out without downshifting. This bike is not a low grunt V-Twin. You really need to keep it up in the power band, i.e. over 3000 RPM and still think about downshifting when you want to speed up.

[dnifong]

Steve,

No it's not related to engine load. It does appear worse at lower RPMs but that could be related to slower speed and the ability to hear better. I could hear it today on the interstate at cruising speeds. I do have an exhaust leak that seems to go away with engine heat. I order bolts and seals today.

the bike has 31k and the valves have never been adjusted that I know of. Could the valves make a similar noise.?

[MikeERideWNC]

What octane are you using?

With 87, mine totally hates the uphill side of the mountains.
Especially, two up.

[dnifong]

Super only, always brand name. I am new to the LT and have put about 2.5k on the bike. I dont have BMW within 3 hours. I really flogged it this weekend, and I worried about the noises that I'm hearing now.

same question over again: can the LT spark knock if it is not malfunctioning or will the computer take over like a modern car engine and prevent it from happening? What are the common noises from this bike? Can valve train noise sound similar to spark knock.

I dont mind taking it apart to try to find the problem, just looking for common failures or noises that mimic spark knock. thanks, Dale

[dnifong]

what about a power commander where you have control of the timing?

dale

[jzeiler]

There is a static timing adjustment defined in the manual. There is no knock sensor on the LT. The valves always wear tight (valve seat erosion) so it is not that. You say you only have a little time on the old girl, could it be you have changed something (turned the radio down, changed helmets etc)? Often we hear strange and unusual sounds that were always there but did not notice. The injectors can be pretty noisey as well. Best to have some other LT rider take a listen to rule out normal sounds, before tearing into an other wise OK machine.

Oh yeah the exhaust leak will make all kinds of noise that changes with temperature. Get that settled first then look for the "other" source of noise.

[Steve_R]

Well, it's only about 3 hours from here to Dublin, GA. Maybe I should ride down on the weekend and take a listen. What say ye, Dale?

[dshealey]

Everything is controlled by the Motronic (computer) on the bike. There is NO timing adjustment.Yes there is Steve! The plate that holds the Hall Effect sensors is adjusted to have the static timing at 0.010" BTC. You have to use a rod in the spark plug hold for #1, and a dial indicator to read the setting. A volt meter on the lead from the correct Hall sensor is used along with the dial indicator reading to set it.

[Steve_R]

Yes there is Steve! The plate that holds the Hall Effect sensors is adjusted to have the static timing at 0.010" BTC. You have to use a rod in the spark plug hold for #1, and a dial indicator to read the setting. A volt meter on the lead from the correct Hall sensor is used along with the dial indicator reading to set it.THE Doctor has entered the building and I stand corrected. :)