Super Trapp, open exhaust?

[BWPNelson]

I have a 1995 XR 600, it has an aftermarket super trapp exhuast on it, and i was wondering if it would harm my engine to run it without any disks. Any input would be much appreciated!

[Onederer]

Not at all, go ahead and do it, it will sound so awesome. Everyone loves a obnoxiously loud motorcycle.

[keithluneau]

It will throw your jetting off, and hurt your ears! Not sure if it'll hurt anything beyond that, but you'll more than likely loose power either way, you need a little back pressure. Besides, everyone within a mile radius will hate you and everyone else that rides a dirtbike for years to come... ?

[LT1coupe]

With or without the end cap?

[ThumpNRed]

My $.02... (what it's worth)?

Open megaphone exhausts (what you have when you remove the end cap and discs from a supertrapp) were popular on thumpers 20+ years ago. They actually sound good from about a mile away! Anything closer though and they are LOUD. I can remember TT500s ripping around the hills with open pipes... no mistaking when one was coming.

As has been said elsewhere, you would probably have to rejet and the lack of back pressure may actually make your powerband worse instead of better. You may end up with a bike that makes less power down low in the powerband with a bit more "hit" higher in the rpms. This is counterintuitive with a large bore thumper as they arent built to spin at high rpms. Also consider that having a dog on the bottom with a big hit in the higher revs is at best hard to ride and probably dangerous. If you want a bike with a powerband like that... start looking for a CR500

[ThumpNRed]

With or without the end cap?

Didnt consider that! With the endcap and no discs would be like stuffing a sock in the end of the pipe! wheeeeze ?

[Onederer]

With or without the end cap?

Read the tittle in the first post.

[scarty111]

Get one of these end caps, you can open or close it! LA Choppers Exhaust End Cap for 4 in. SuperTrapp External Disc Mufflers

Dennis Kirk Part #: 4402588

Manufacturer Part #: 18120150 http://www.denniskirk.com/denniskirk/b2c/product_images/1/8/1/150pix/18120150.jpg

[Onederer]

I'd spend a couple hundred on a Supertrapp then another 55 to defeat the whole purpose of the design, heck yeah. How about a flame thrower too, noise and light, a complete show to awe the crowds that will gather to witness the awesomeness of mans ego incarnate.

Edited March 1, 2010 by Onederer

[scarty111]

I'd spend a couple hundred on a Supertrapp then another 55 to defeat the whole purpose of the design, heck yeah. How about a flame thrower too, noise and light, a complete show to awe the crowds that will gather to witness the awsomness of mans ego incarnate.

?

[LT1coupe]

Read the tittle in the first post.

The title does not mention the end cap & if the end cap is removed the disc don't matter ?

[scarty111]

The title does not mention the end cap & if the end cap is removed the disc don't matter ?

You stick an allen wrench in the end of the cap and turn to open it for straight thru running exhaust or closed and it directs it thru the discs.

Edited March 1, 2010 by scarty111

[DGXR]

With "open exhaust" in the subject, I am sure everyone -- well, almost everyone -- knew he was talking about running it with no discs and *no end cap*.

Using an end cap with no discs would be the opposite of open exhaust, with the exception of that 2-way end cap scarty is talking about, that's pretty trick! ?

[HeadTrauma]

Running a SuperTrapp with an open end will not hurt your engine if the necessary jetting changes are made.

That said, SuperTrapps are not known for being quiet anyway and taking the end off will make yours ear-splittingly loud. It will also eliminate the spark arrester, so you'd be set up for two citations.