|Topic Review (Newest First)|
|Aug 20th, 2018 3:30 pm|
The OEM headers including 2x M18 bungs = 2.736 kg. Thats less then 500 grams of weight savings. They look good though.
|Aug 15th, 2018 3:02 pm|
Spaghetti for dinner today. 2.252 kg. I would say these are pretty good quality. I ordered M18 bungs for data logging.
|May 21st, 2018 7:55 pm|
Originally Posted by califblue View Post
Add says for 900SS/SL and also 400SS (there are many like that), will those headers really fit the 900 and the 400, what about the 600 and 750?
Will the carby headers also fit the ie. bikes, will the 900ie headers fit the 750ie, will the 750ie fit the 620ie?
To what extend are Monster and SS headers interchangable?
Can those with knowledge regarding this please inform the rest of us.
Though systems (headers) for the 900's are quite common, they are really rare for the smaller bikes.
Will 900 headers fit the 750, how difficult will it be to make them fit?
I've been looking for a really nice system for the 750ie for the past 6 years without any success, custom building a system (in ZA) is not a option, so the only way eventually would be to buy something like in the add and modding it for purpose.
Any help would be appreciated?
|May 17th, 2018 10:54 am|
|May 14th, 2018 7:39 am|
Originally Posted by Feral_Ducati View Post
|May 13th, 2018 7:38 am|
|Feral_Ducati||I recently bought a 900ss from interstate unseen. When it arrived, a nice bonus - Staintune full system. Score!,|
|Feb 28th, 2018 2:03 pm|
Originally Posted by grrss View Post
|Feb 25th, 2018 12:10 am|
Originally Posted by Neil66 View Post
|Feb 24th, 2018 11:14 am|
Only one day left...!
Not my ad but a good one for someone needing one!!
|Jan 27th, 2018 2:04 pm|
Some stuff I wrote for a a friend of mine....
My 2 into 1 on the Frankencati works pretty well and has now been copied on about 6 or 7 bikes on this forum all with good feed back. While not developed/tested on the dyno like my bucket pipes I think It works pretty well.
4 stroke exhaust design is much simpler than 2 stroke design because you are not having to concern yourself with creating back pressure. In a a four stroke design the only back pressure consideration is t have as little of it as possible!
Four stroke exhaust are optimised for extraction effect, where one cylinder's low pressure wave in it's header helps create a well timed low pressure point to help suck out the gases from another cylinder just as the exhaust valves in the other cylinder opens.
In a typical exhaust system there will be several low pressure waves reflected back to the exhaust valves. The first one will be where the first inter-conection point between headers occur. There will also be a reflection from each point the exhaust diameter changes, such as the entry to the muffler and also a reflection point from the exit of the slip-on to the big wide world. Multiple reflections like this mean that you have the extraction effect happening across a number of rev points.
A small difference in length to these reflection points will shift the revs at which extraction occurs. Easy to see this on a dyno with a single cylinder bike if you make a long header and then just cut 25 mm off it in between dyno runs and observe the shape of the torque and hp curve shift. I observed this, and a similar, but even more pronounced effect when I lengthened and shortened the inlet tract on my bucket with my variable inlet length tract set up (especially if I altered the jetting to suit each length.)
On a bike where you want to create maximum power at shorter revs you need to have the reflection points closer to the exhaust valves.
With an even firing 4 cylinder or parallel twin it is easy to create an inter-cylinder extraction effect on all cylinders.
With a even firing 4 cylinder the interconnection (crossover or merge) points for inter-cylinder extraction are quite close to the exhaust valves as the firing intervals between the cylinders is much less (half) that of an even firing twin cylinder engine and this makes the packaging on a four cylinder bike easier to achieve. If you look at a modern high revving Japanese 4 cylinder bike, you will see the merge points are on the down pipes quite close to the exhaust valves.
All else being equal on an EVEN firing 2 cylinder the merge points will be twice as far from the exhaust valves. If you look on a parrallel even firing twin cylinder bike, the first merge/cross over point will typically be under the engine comparatively quite a long way from the exhaust valves.
HOWEVER with the uneven 270 and 450 firing interval on a V-twin Ducati you can't create a inter cylinder extraction effect to BOTH cylinders with equal length headers of course.
Here is the thinking I went through when I designed the Frankencati 2 in to 1 system....
On a Ducati twin with it's uneven firing interval you could create a milder extraction effect to BOTH cylinders with two interconnections (A merge and an earlier interconnection pipe for example each timed to suit the firing interval to the other cylinder) and it appears that Akrapovic did attempt exactly this on one of their exhaust systems for the earlier air cooled Multistrada. (Search the internet and you will find pics of this system.)
While it is not simple to create an inter-cylinder extractor effect for BOTH cylinders to suit the Ducati uneven firing order, you can tune the length of the headers so that the low pressure wave reflected back from the end of each header would help extract gases from it's own cylinder (self-cylinder extraction as opposed to inter-cylinder extraction, for want of better terms). When I looked at doing this, the calculations suggested the length of the headers need to be quite long to achieve this at the revs of interest and packaging long enough headers on a V-Twin Ducati to achieve this is problematic. For this reason I made the headers on my 2 into 1 as long as possible. If I still had ready access to a dyno I would be keen to make up a few variations and test them back to back on the dyno as I did with my bucket pipes.
Everything is just theory and pub talk unless you make multiple variations and test and measure on the dyno.
I tested 9 exhaust variations of design and lengths on my bucket before settling on the current pipe...and now I am changing the cams which will change the valve timing so I will need to go and make up some more exhausts to test to optimises for the new cam timing.
The overriding reason in the end that I opted for a two into one system for the Frankencati is that the one clear and irrefutable advantage of a two into one system is that you save a lot of weight!
|This thread has more than 10 replies. Click here to review the whole thread.|