I'm having an issue with my bike knocking when it's cold. The knock does not sound like traditional lifter noise as its a much deeper sound. The noise appears to be coming from the primary side of the engine but I can't pinpoint it. If I run the bike for about 20 minutes and let it come up to full operating temperature the sound almost disappears. I recently replaced my worn stock compensator with a baker comp and this didn't seem to affect the sound. This is going to sound crazy but i noticed the sound after an oil change using a wix filter and 20-50 mobile 1. Any advice on what to look for? Build is in my signature. Thanks!

 

Can only offer this.... Mobil 1 is THE WORST as far as noise goes in my '15 Limited Low. I'm sure it's fine oil, but it just seems too thin or something, despite what "weight" it is. It would not surprise me at all if you changed oil & the noise went away.

 

Piston slap would be my first guess, due to it going away when warm.

 

Another vote for piston slap. Also not that M1 is a superior oil, but like most synthetics, it is on the low end of the viscosity scale, and tends to not cover up noise like an oil on the thicker end of the scale.

 

Try running Formula+ in the primary. Had very similar symptoms. Changed to Formula+ and no more noise. I have since put 50K on the bike and the noise never returned. Very inexpensive too.

 

I am running formula plus in the primary.

 

This is a fairly new build on the engine so I'm really hoping it's not piston slap.... If it IS piston slap, what options do I have?

 

The 99 Chevy's came stock with piston slap & would run along time like that. Change back to the oil before, like mentioned & run it

 

When I seen a 96 piston I thought it had way less saport on skirts than the 88. Then going bigger only is going to make this worse.

 

I agree, Mobil 1 is good oil but it transmits noise really bad. I went to Valvolune VR 20/50 and the noises went away-- sure can't hurt to try