Lowmount Exhaust Chop - How Much to Chop?

[roy-nexus-6]

I am looking to mod my stock pipes by cutting, & need some specific info.

Pic below shows my Senna S4 before and (photoshopped) 'after' pics. The orange dot on the 'before' pic shows where the word 'ducati' is stamped in the metal - about 3 1/2 inches (9cm) from the end of the unmodded pipe.

I want to shorten my pipes... but DON'T want to cut so far in that I cut through all three inner tubes (see pic below, from TOB).

1. How far down the pipe can I cut before I hit all three tubes? (distance X in the illustration below).
2. How thick is the metal of the internal pipe? Can it be welded instead of pop rivetted? Is it aluminium or steel?

caffeinejunkee has a great write up on here,.. but I'm still trying to find out how far I can cut back without hitting all three tubes.

http://ducatimonsterworldwide.org/index.php?topic=2312.0

[herm]

i cant add anything useful to help you since i took over 6 inches off my last set of low pipes.
but i am curious why you don't want to cut through them? are you trying to shorten them without making them louder?

[mxwinky]

I'm kind of curious on that point too.  Anyway, I think for aesthetic and sound reasons the red dot point you've indicated is a pretty good place to cut to.  I've seen and heard a ton of cut pipes and find that the real shorties are a bit too loud, IMO, and don't really look that good, again IMO.  The three-quarters length you're indicating with your red dot seems about perfect.  I did that exact mod on a set of Monster pipes a couple of years ago and was very happy with the results.  Go for it!

[Scooter Montgomery]

I cut 4" off mine, looks and sounds great.

[roy-nexus-6]

i cant add anything useful to help you since i took over 6 inches off my last set of low pipes.
but i am curious why you don't want to cut through them? are you trying to shorten them without making them louder?

Yes! The police in Aus are like raving hounds when it comes to motorcycles. So I'd like to shorten them to make them look better,.. but not necessarily louder.

I cut 4" off mine, looks and sounds great.

Great! At four inches, did you cut through all 3 pipes? 

[Scooter Montgomery]

http://myspacetv.com/index.cfm?fuseaction=vids.individual&videoid=4592375

http://myspacetv.com/index.cfm?fuseaction=vids.individual&videoid=4592310

The sound quality is better in really life. I probably shouldn't have done it indoors.

[minnesotamonster]

ok so this might be a dumb question but here goes anyways. I want to chop my stock low mounts as well. Do you just pick a spot, cut all the way through the pipe, and rivet the cap back on??  Is there anything else that needs to be done?

[roy-nexus-6]

ok so this might be a dumb question but here goes anyways. I want to chop my stock low mounts as well. Do you just pick a spot, cut all the way through the pipe, and rivet the cap back on??  Is there anything else that needs to be done?

No such thing as a dumb question

Excellent write up can be found here - it includes pics.

http://ducatimonsterworldwide.org/index.php?topic=2312.0

[Scooter Montgomery]

I looked inside mine this morning. I only cut 2 of the 3 pipes. One was short enough that I missed it.

Bob

[Big Troubled Bear]

OK, I have checked mine that I cut.

The cut was made just before the D of Ducati on the R/H side muffler, similar amount taken of the L/H side.
I cut through the one pipe that exists at the back

The pipes are a bit louder, but has a deeper sound

[roy-nexus-6]

I looked inside mine this morning. I only cut 2 of the 3 pipes. One was short enough that I missed it.
Bob

Thanks for the update! Do you still have the full word 'Ducati' on the right hand pipe? Approximately how far from the end is it? 

OK, I have checked mine that I cut.

The cut was made just before the D of Ducati on the R/H side muffler, similar amount taken of the L/H side.
I cut through the one pipe that exists at the back

The pipes are a bit louder, but has a deeper sound

I got so excited when I read Big Bear's post, I PM'd him to confirm - no answer as yet: here's my PM.

Let me confirm - you cut through only ONE pipe - that would have to have been the pipe that exited the exhaust? So you're cut occurred in region X of my figure in my post? That 'D' is exactly 3 1/2 inches down the right hand exhaust.. so X must be longer than 3 1/2 inches.

The reason why I am so excited is that you have described cutting EXACTLY where I want to cut!  I'd be one happy camper if I can make the cut this upcoming weekend!  

[Scooter Montgomery]

Thanks for the update! Do you still have the full word 'Ducati' on the right hand pipe? Approximately how far from the end is it? 

I got so excited when I read Big Bear's post, I PM'd him to confirm - no answer as yet: here's my PM.

Let me confirm - you cut through only ONE pipe - that would have to have been the pipe that exited the exhaust? So you're cut occurred in region X of my figure in my post? That 'D' is exactly 3 1/2 inches down the right hand exhaust.. so X must be longer than 3 1/2 inches.

The reason why I am so excited is that you have described cutting EXACTLY where I want to cut!  I'd be one happy camper if I can make the cut this upcoming weekend!  

Its right through the middle of the "D".  Different companies made pipes for Ducati so it might vary from company to company mine are made by Remus.

[roy-nexus-6]

Its right through the middle of the "D".  Different companies made pipes for Ducati so it might vary from company to company mine are made by Remus.

I just got a note from caffeinejunkie: I mentioned his excellent write up at the start of this thread. In the case of his pipe, X was equal to about 5 and half inches. So you are absolutely right - it seems to vary from manufacturer to manufacturer.

Well see what I find when I do the chop! I'll include all the info I've collected in this thread in a mini how-to write up. Thanks again to everyone who provided info.

Cheers. 

Roy