Tune Tic

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gentsvmax

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So I got my shiny new Ultrasonic cleaner, got my carbs all shiny new clean,
I intended to do a thorough tune, the Top Down tune. 20210925_112410.jpg

Main jet selection was easy as it gets. I think this bike goes hard all the way until I get out of it.
To check the test off the list I gladly ran it anyway.... now I've got a tic out of cyl#3.
Stopped the tuning cycle for sure.

Checked compression, carbs off and found #3 to like 40lbs less than the other cyls. approx. 170p.s.i..
So off with the heads!

I have always had an issue with cyl#2 running way leaner than all other's, I've been wanting to weld bungs in this header for the inevitable LM-2 as this wouldn't have been my first "top down tune" attempt and I am TIRED of playing the jetting game.

I cannot enter my garage without the protection of my new JLABS noise cancelling ear buds.
The mod monkey is fully aware of the issue with the "tic".
He sits here and there brooding, barely containing his under breath shrieks of 'long rod' and 'big bore'. That tic has nearly driven him to mod monkey sycosis!

Although this tic isn't steady, it will be addressed. We are in a sort of Indian summer here in Denver, still some good fall riding weather.
I'm not sure now's a good time to pull the motor.
 
Don’t do it gentsvmax. We’re doing some late season riding here in New England and it’s some of the best riding of the season. My bike loves this cooler denser air. Twist it to the stops and drown out the mod monkey at least temporarily.
 
So I got my shiny new Ultrasonic cleaner, got my carbs all shiny new clean,
I intended to do a thorough tune, the Top Down tune. View attachment 81180

Main jet selection was easy as it gets. I think this bike goes hard all the way until I get out of it.
To check the test off the list I gladly ran it anyway.... now I've got a tic out of cyl#3.
Stopped the tuning cycle for sure.

Checked compression, carbs off and found #3 to like 40lbs less than the other cyls. approx. 170p.s.i..
So off with the heads!

I have always had an issue with cyl#2 running way leaner than all other's, I've been wanting to weld bungs in this header for the inevitable LM-2 as this wouldn't have been myIs 170 first "top down tune" attempt and I am TIRED of playing the jetting game.

I cannot enter my garage without the protection of my new JLABS noise cancelling ear buds.
The mod monkey is fully aware of the issue with the "tic".
He sits here and there brooding, barely containing his under breath shrieks of 'long rod' and 'big bore'. That tic has nearly driven him to mod monkey sycosis!

Although this tic isn't steady, it will be addressed. We are in a sort of Indian summer here in Denver, still some good fall riding weather.
I'm not sure now's a good time to pull the motor.


What did you do to differentiate between the heads/valves or the rings? 170psi are the higher reading cylinders I'm guessing?
 
What did you do to differentiate between the heads/valves or the rings? 170psi are the higher reading cylinders I'm guessing?
Yes sir, great question. I have not yet made an attempt to verify either.
However I do hear something in the #3 and 4 header tubes all the way back to the collector, like something loose rattling around in the tubes.

Instead of working on my machine which should be priority I'm working on other people's toy's, pay's the bill's though.
20211108_152840.jpg20211108_163501.jpg
 
Yes sir, great question. I have not yet made an attempt to verify either.
However I do hear something in the #3 and 4 header tubes all the way back to the collector, like something loose rattling around in the tubes.

Instead of working on my machine which should be priority I'm working on other people's toy's, pay's the bill's though.
View attachment 81191View attachment 81192
If OEM exhaust, the inner exhaust tube has a history of making noise. There should be some threads here on that. I believe the fix is simple. You may not have an issue with your motor. Gen 1's can be noisy, but not from the valve train usually.
 
If OEM exhaust, the inner exhaust tube has a history of making noise. There should be some threads here on that. I believe the fix is simple. You may not have an issue with your motor. Gen 1's can be noisy, but not from the valve train usually.
That's what it is. The inner tube has come loose. Buddy of mine had that problem. Sounded freaking awful, almost like a rod knocking in some cases. In others it sounded like a big muffler on an old Chevy dragging the ground.

He just bit the bullet and bought new downpipes and put those on. (He already had Supertraps and just moved those to the new downpipes.)
 
If OEM exhaust, the inner exhaust tube has a history of making noise. There should be some threads here on that. I believe the fix is simple. You may not have an issue with your motor. Gen 1's can be noisy, but not from the valve train usually.
Thank you for the input on this. Today I fired it up just to get it over to my garage, the #3 cyl. tic was intermittent but I could stop it by unplugging that C.O.P., the bike still runs well on three cylinders LOL..
Now in the alley by my garage the acoustics off other doors were perfect, I could really here this rattle in the #3 pipe between the stock peg location and the forward control brake/peg. I'm going to get the bike up and probe with my telescoping magnet just to see/feel if a fastener or something else metal is trapped between the block and pipe.
 
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