Black cap bean can modification

mean gene

mean gene

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Considering putting stock exhaust back on my Mk III. Is there any modifications I can do internally to get better performance but have original looks. Same with plastic air box
 
I wouldn't worry about the airbox. The Black Cap silencers and the plastic air box were designed for noise reduction.
The Black Caps cause a lot of power sucking exhaust restriction.
The airbox works the other way. It was designed to reduce induction noise by slowing the air flow. This was done by having a large airbox capacity and a large filter area, all good for power output.
Do remove the snorkels.
I wouldn't waste time on the Black Caps as they were so horribly debilitating to my 850 on power testing. I also happen to prefer the look of the peashooters, which are very good for power.
If you are set on the Black Caps, there is probably a way to core them out.


Glen
 
First I got rid of the rubber airbox snorkels. Then I got rid of the whole exhaust system , moving to Feked and reverse cone silencers. Then I had a problem. Never could dial in perfection until in desperation I ordered in 2 slides of size 3 instead of the stock 3 1/2 . Made all the difference to the MK 111. Smooth as silk now. Good luck .
 
Looks like they are out of stock at the moment.
The other negative on the Black caps is the extra weight.
Perhaps these open jobs aren't so heavy, however the original Black Caps feel as though they are made of lead!
 
(Obviously not "650cc")

"Our HD triple plated silencers are made by Armours, using our own design corrosion resistant construction, typical internal design is all metal non-restrictive straight through construction with an exit main gas stream diffuser. This design gives a nice tone without the use of moisture retaining absorption. Baffle design will vary according to type."
 
I like my original Favill designed Annular Discharge Silencers, my MK3 goes just fine and is quiet. Be careful comparing the real ones to aftermarket they are built different.

Black cap bean can modification
 
No wonder they weigh a ton It's interesting that the 5 smaller tubes remind me of Dunstall mufflers. Thanks Jimbo
 
mean gene said:
Considering putting stock exhaust back on my Mk III. Is there any modifications I can do internally to get better performance but have original looks. Same with plastic air box
Click to expand...
I remember back in the day owners would drill a series of small holes in the black end cap so that it resembled a pepper pot, to try and get back lost performance.
know idea if it worked but probably sounded faster.
 
jimbo said:
View attachment 82603
Click to expand...
That is very interesting to see!

What struck me is, even without the baffles and reverse flow etc, even if you removed all of that, what you have essentially is a VERY long and quite small diameter pipe.

I’m even wondering if perhaps that is at least part of the reason for these ‘strangling‘ the performance ?

I also wonder how different they are internally from the T160 versions ?
 

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