Gen 1 - Loud tapping sound between 0-4K RPM and only when in drive

[CZ Eddie]

Have a loud tapping sound coming from the engine area.
It only occurs between 0 RPM and ~4000 RPM, then goes away.
And I only hear it while in drive.
So if I am in Neutral and rev the motor, I don't hear any tapping.
If I'm at a dead stop and put it in gear, I don't hear anything.
But if I start to take off, I hear the sound from 0 RPM up to 3500-4000 RPM and then it goes away.

The sound went away completely after I installed the resistor mode (DIY TRE).
And was gone for like 4000 miles.
Then I pulled the resistor and immediately the loud tapping came back.

So what is it about the TRE that is preventing the tapping sound and what might be the problem causing it?

Gonna get a Dyno Tune this Sunday and I've got a feeling that'll resolve the issue.
But am interested in hearing more opinions.

Remember... the tapping is not always there.
Only when in gear and when moving between 0 RPM and ~4000 RPM.

 

[dillon]

Chain and sprockets, Just doing mine for the same reason. I was convinced it was a gear box problem but it turned out to be a tight spot on the chain.

 

[CZ Eddie]

Chain and sprockets, Just doing mine for the same reason. I was convinced it was a gear box problem but it turned out to be a tight spot on the chain.

The sound went away completely after I installed the resistor mode (DIY TRE).
And was gone for like 4000 miles.
Then I pulled the resistor and immediately the loud tapping came back.

 

[CZ Eddie]

Went to Johnny Cheese today for the dyno tune.
Mr Cheese immediately diagnosed the tapping sound as an exhaust leak.
I guess it makes sense. When I removed the TRE, I also tightened my header bolts at the same time.
Quite some time back I tightened the exhaust header bolts also. They were so loose that I could twist them with my fingers!
Mebbe that was the same time I installed the TRE, which is when the tapping went away.