'77 GS400X Stock Exhaust Modifications

[rymac11]

I own a '77 GS400X and I am curious about modification of the stock exhaust. I know from reading in other threads how many of you feel about "loud" bikes, however my intent is not to create an obnoxious machine. I removed the mufflers completely and loved the tone I got however they were just too obnoxious to leave off--not to mention I had about zero low end torque. As a compromise I decided to modify the stock exhaust. I have already take an 7/8" hole saw and drilled out the first two baffles. This gave me about a 5% increase in sound and no change in tone. So I then took a 2" hole saw and drilled through the rear of the exhaust and pried out the baffle that was attached. I am left with a sound that is, in my opinion, pretty nice and not too loud; however, optimally I would like it to be a little deeper. I didn't want to do anymore drilling without getting some input as I don't want to overdo it. Tips would be much appreciated!

Thanks,
Ryan

[Steve]

The only way you are going to get a "deeper" tone is to get a larger bike.

Enjoy your bike while you can.
Opening up the mufflers is going to require re-jetting the carbs.
If you don't do that, you may damage the engine.
Then, it's going to be REAL quiet.

[rymac11]

Do you think what I have done so far warrants a rejet?

[Steve]

Do you think what I have done so far warrants a rejet?

Did you read what I wrote?

Opening up the mufflers is going to require re-jetting the carbs.

Did you do ANYTHING to "open up the mufflers"?

.

[rymac11]

Yes I did read what you wrote, however the way you worded it was confusing. Did you see what I wrote?

I have already take an 7/8" hole saw and drilled out the first two baffles. This gave me about a 5% increase in sound and no change in tone. So I then took a 2" hole saw and drilled through the rear of the exhaust and pried out the baffle that was attached

A simple, yes you need to rejet would have sufficed. Thanks for the help though.

[Steve]

A simple, yes you need to rejet would have sufficed.

Sorry, I didn't use the word "yes", but I did give it you in plain English.
(and in the first response, too)

Opening up the mufflers is going to require re-jetting the carbs.

.

[Bonehead]

As Steve said, you WILL need to rejet. However, instead of modifying the stock exhaust, why not get an aftermarket one? Or, simply fabricate your own out of some straight piping. Whatever you do, modifying an exhaust will warrant a rejet. Do you happened to have pods or the stock airbox?

[oldpara]

I have a couple of MAC slipon mufflers I'll sell.
I took them off my GS250, (too loud).
They'll accept 1.5" OD pipes, chrome, nice shape.
$100.00 you pay shipping.