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Discussion Starter #1
now that i use one of those small batteries which is tucked into the tailof my 06 mono i was able to remove all supports for the battery box.this opens a lot of room . when i go for my engine work .i will rework the exhayst to shorten the distance from head to the end of silencer .the way i plan the new pipes i can shorten this distance by2 feet for each. this will free up breathing i figure by #$%^&* now i am not a genius but it must have the same results as increasing the diameter of the pipes
 

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Sounds interesting. Conventional wisdom is that shortening the pipes will have the same effect as bigger diameter and increase top end horsepower but will decrease torque. Let us know how it goes.

I can tell you that I can feel a torque reduction going from my long dual termi pipes to my shark 2 into short single pipe exhaust. I have yet to see if it has an increase in horsepower. I take it to the track Monday so we'll see what the pants-dyno says. I'll check the real dyno later.
 

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Discussion Starter #3 (Edited)
to make it worthwhile for good gains i will do a port and polish, mbp tulip valves, high comp pistons ,big bore. right now i,m at the lightening phase of the bike along with vissual enhancements
i would like to try st3 thottle bodies as well 50 mm and i think i would have a missle
and i like riding in high revs .i went with a 14 front and 42 rear so i now use a six gears
 

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What are you going to do with the Zards? If you unload them, I may be interested...

It would be nice to see your mods as well. Pix???
 

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Actually, conventional wisdom is that longer is usually better overall: that (within reason) a longer bigger exhaust is better than any shorter exhaust in combined HP and Torque. Even GP bikes have exhausts that use all the available length of the bike. Straighter is always good, but not necessarily shorter.
Drag machines are the only place I know of where short rules.

So, if you're building a dragster, then it's probably the way to go.
 

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Discussion Starter #6
the zards are going to be modified .the upper is now coming from the virt cyl
and bottom from the front. the balance pipe will goe from exhaust port to exhaust port since i eliminated the battery bow and mounts there is a lot af room to be creative . i'll use the existing front exhaust for doing my alterations and my brother will tac in position and then weld it up maybe in a couple of weeks i'll have something to show. this weekend i redid my mono seat narrowed the sides by 1 inch each redid the front mounting to draw
the cowling in as well
when i figure out this picture thing i will post
 

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Discussion Starter #7
the biggest problem with the ds is breathing by shortening the exhaust from 3.5 ft to only 2 ft should let the engine breath easier and increase fuel mixfor mor power . if i'm wrong then i'll but another set of pipes to go on the existing silencers
 

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45mm is enough 50mm will only help you if you go way crazy with the engine.
General rule is to have same dia exhaust as exhaust valve and if engine is tuned go a couple of mm bigger.
I have calculated that 45-48mm and a lenght of 70-78 cm header will be the best.... for my bike that is.
If you go 2 seporate exhaust without them merging you vill get god top end end not so god mid range.

If you go with 2 headers that in some way touch just a little bit at the right point then you will get the best of 2 worlds.

2-1 or 2-1-2 which basically is the same and people say that this is good for midrange but not for top but a spaghetti header gets better mid then a 2-1 and same top as 2-2.

Inlet lenght is allso critical for rpm etc. my calculations is aprox 22-28 cm inlet from plate of valve to end of trumpet. but that allso effects if you are gonna use or even pay attention to 2-3-4 wave harmonics.
2 is plus 10%
3 is 6-7%
4 is 4%

The inlet lenght of the orginal config i guess uses the 2 harmonics since they are something like 30-40 cm if they even pay attention to that.
That means that 25 cm would en up with 3 wave harmonics.

If eventhing is tuned for 5000rpm it will be great if something is tuned for 2500rpm and something else for 5000rpm you will get an curve which is long and without any bigger peak.

All of this is only calculated and not proven in real world which differs big time from what you calculate. only way to know is the dyno.
 

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I`d go for 50mm & not so short:
http://www.ducati.ms/forums/showthread.php?t=21505&highlight=black+sheep&page=4
"The old setup, with the carbs and MSD and stock headers with slash cuts, made 88hp. The new setup, with 2" headers and Hindles, makes 95HP! "
"Both hp and torque are above stock headers from 3500 rpm up to 5000 rpm, where the two curves meet, then from 5000 on up to 9500, there's an increase in both with the new headers."
Pretty amazing w NO hicomps, porting nor cams.

And then add the Wasp inlets & you`ll have a 115 Hp SC!

But I`m just guessing....
 

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Hej Svenne!
 

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Here is a picture of the DP Spagetti version for Monster 1000.

It is a 2-2 with connected header.
It has 45 mm outer diameter with t= 1 mm.
The last 40 mm of the header are 50 mm outher diameter.
The front cyl header is 760 mm long.
The rear cyl header is 660 mm long.
They are connected at
Front cyl header 560 mm from cyl to Rear cyl header 560 mm from cyl
and
Rear cyl header 430 mm from cyl to Front cyl header 690 mm from cyl

/Henrik
 

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Here is a picture of the DP Spagetti version for Monster 1000.

It is a 2-2 with connected header.
It has 45 mm outer diameter with t= 1 mm.
The last 40 mm of the header are 50 mm outher diameter.
The front cyl header is 760 mm long.
The rear cyl header is 660 mm long.
They are connected at
Front cyl header 560 mm from cyl to Rear cyl header 560 mm from cyl
and
Rear cyl header 430 mm from cyl to Front cyl header 690 mm from cyl

/Henrik
Exactly that header i have om my bike, got it today and fitted it a couple of hours ago.
 

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