Help with funk stuff on my bike

[jonnywdwd]

There have been a number of mods and hacks on my 2001, some of which I've figured out and some I haven't. I could use some insight on several things.
First, the tank.... why would there be two symmetrical JB Weld repairs on the underside of the tank on each side near the front. Did anything used to be there?

 

[Isleoman]

There’s nothing in those areas on a standard tank. Can’t think of reason for it to be crash related. Could be close the deepest part of tank where condensation turned to rust I see corrosion starting in other parts of the exterior. Was the bike used for jumps or stunts?

Interesting as Salt Lake City is pretty dry place.

 

[jonnywdwd]

There's not much relevant history of this bike which is known to me. I'm glad to hear that there's nothing missing from the tank there.

What brand of shorty slip-on is this?

It's a bit loud for my liking. The PO gave me the stock muffler and am wondering about putting that back on. The bike has a K&N air filter, the main jets are #120, mixture screws are 4.5 turns out and the two rearward holes in the throat of the carbs have been enlarged. What would be the result of restoring the stock muffler with these existing mods?

 

[Isleoman]

You won't find a bigger fan of the oem exhaust than myself. Hopefully the PO didn’t cut anything where they interface.

Took me a while to see what was going on in the last photo. At first i thought it was a Roadrunner (bird) trapped in springs.

 

[Jboat]

+ 1 for the OEM exhaust.

The bike will probably run better with it on and you may feel more low end torque due to the back pressure…

 

[killer5280]

Yeah, I'd put the stock muffler on ASAP. I have an Akrapovic slip-on that's just right. Almost as quiet as the stocker.

 

[jonnywdwd]

Most of my other bikes have been stock and I've had no desire to change them.
What I understand from reading about slip-ons is that a slip-on alone will negatively affect performance unless re-jetted.
So is the opposite true - if I reinstall the stock muffler on a modded/jetted bike will I be required to return the jets and air filter to stock in order for it to run right?
BTW I'm not interested in maximizing horsepower. It has more than I need. I would just like a quiet bike which is reliable and runs well.

 

[Isleoman]

Most of my other bikes have been stock and I've had no desire to change them.
What I understand from reading about slip-ons is that a slip-on alone will negatively affect performance unless re-jetted.
So is the opposite true - if I reinstall the stock muffler on a modded/jetted bike will I be required to return the jets and air filter to stock in order for it to run right?
BTW I'm not interested in maximizing horsepower. It has more than I need. I would just like a quiet bike which is reliable and runs well.

Switch them and find out ….shouldn’t take more than 30 minutes. You have more faith than me as to previous owner jetting it.

 

[Blue Flash]

The difference between the stock muffler and a slip-on should be minimal. We have had a lot of people do the jet kits with and without a muffler change. No problem either way, assuming the bike was re-jetted properly.