Here's my previous post about misfiring:  http://gstwins.com/gsboard/index.php?topic=50715.0

I have since done the following:

- oil change
- rechecked valve clearances.  I am on the loose side of the spec.  I'm at .1mm .1mm .07mm and .09mm.
- installed Buddha's jet kit with #20 pilot, #130 main, 2.5 turns on the pilot screw
- new OEM air filter
- new fuel lines

Today I took it out for the first time and turned around and went home because it was bogging down.  Try to give it any throttle and it would bog down, which is odd because sitting on the center stand in neutral, I could rev it all I want.

What really concerns me is a sound that has not ever gone away -- it's been there since before I changed jets.

Starting at 1800 to 2000 rpm, there will be what I called misfiring in the other thread.  It's not so much backfiring towards the exhaust or the air box.  Instaed, it has a mechanical, metal, deep clunking sound to it and it occurs simultaneously with a drop in rpm.  I don't want to wreck my engine...does this ring any bells for anyone?  Is this knocking?

Regarding the bogging down, I believe it could be the following:

- too rich, but that wouldn't make sense to me given lack of smoke, smell, etc.
- fuel starvation issue.  I had a new tank bag over the gas cap, could that do it?  Petcock was set to Run when it was bogging.  When I turned around and went home, I switched to PRI and it seemed better...
- way leaner than it's ever been?  again, doesn't make sense with the new pilot jet.

I could believe the bogging down is just a fuel starvation issue and not worry about that.

The clunking I hear scares me though.  If it's knocking or preignition caused by a lean condition, how could I be leaner with new jets?  I did verify the size of the old jets -- they were marked with stock sizes (#17 and #127.5).

If I can give you advice it would be that:
make your posts shorter, much shorter, and get straight to the point. Usually people are too lazy to read long posts.

I just opened yours and immediately closed it, and when I realized why I did that (too long) I thought I should let you know.

cheers

It sounds like you may have an exhaust leak, or a cam shaft drift (drop in rpm isn't a symptom though) and maybe a tight cam bucket.
Cool.
Buddha.

You'll know if you have a rod knock. It sounds like someone hammering on the side of the case with a steel mallet. A nice, deep, low, hollow sound. Oh, and you'll here it at all RPMs, it will just get faster.

Then there's ticking, like a sewing machine. I think they all make that noise. Higher pitched. Louder ticking may be exhaust leak.

You're not hearing it at all RPMs. Either your carbs have issues or it's ignition.

Have you completely cleaned the carbs, or did you just change the jets?

There's not much to go wrong with the ignition, but you might pull the RHS cover and check the rotor / stator plate and see if all's well. It's a 2 minute job to check it.

Wait..isn't there a recall on that or something? It's what buddhas talking about.

Quote from: kml.krk on March 05, 2010, 06:45:54 PM
If I can give you advice it would be that:
make your posts shorter, much shorter, and get straight to the point. Usually people are too lazy to read long posts.

I just opened yours and immediately closed it, and when I realized why I did that (too long) I thought I should let you know.

cheers

I appreciate the advice; sometimes I do the same thing with long posts.

The problem, if it be that, is I take time to write the post out to cover as many details as I can so we don't waste each other's time.

Verbosity is necessary in descriptions of mechanical systems.

Quote from: dauphinc on March 05, 2010, 09:39:51 PM
Wait..isn't there a recall on that or something? It's what buddhas talking about.

eh?  Recall on what?

Quote from: noiseguy on March 05, 2010, 09:23:29 PM
You'll know if you have a rod knock. It sounds like someone hammering on the side of the case with a steel mallet. A nice, deep, low, hollow sound. Oh, and you'll here it at all RPMs, it will just get faster.

Then there's ticking, like a sewing machine. I think they all make that noise. Higher pitched. Louder ticking may be exhaust leak.

You're not hearing it at all RPMs. Either your carbs have issues or it's ignition.

Have you completely cleaned the carbs, or did you just change the jets?

There's not much to go wrong with the ignition, but you might pull the RHS cover and check the rotor / stator plate and see if all's well. It's a 2 minute job to check it.

This is a very mechanical sound, not hollow.  It's like a clank and you can feel it in the handlebars.

The ticking is fine; just the valves I think.

The carbs were cleaned before I switched jets.  I don't believe there's been a change in sound regardless of carb adjustments.

Thanks, I'll check what you suggested.

Quote from: The Buddha on March 05, 2010, 08:58:58 PM
It sounds like you may have an exhaust leak, or a cam shaft drift (drop in rpm isn't a symptom though) and maybe a tight cam bucket.
Cool.
Buddha.

When you say bucket, you don't mean shims?

Would cam shaft drift (I don't know what that is) be consistent or intermittent?

Starting up cold I get steam in my exhaust and it doesn't look like it's leaking exhaust anywhere but where it should.