Exhaust internals

[Nick]

My next plan for improvement is the exhaust internalls my Mk 2 number 82 has different sized holes to the drawing on here is the drawing correct or did they change it later on?
 Drawing                                                        Mine
OD at end 55mm                                            45mm
OD at end start of taper 48mm                        40mm
Perforated tube 50 mm                                   38mm

Would my bike benefit from enlarging these to the drawing?
With the silencer off is it wise to clean out the baffle tube and How?

Any advice greatly apprecated

[hendred]

I think the dimensions on the drawing are wrong.  My silencer is about the the same dimensions as yours.  The baffle is easily removed after removing the alloy end cap.  The space between the baffle and the exhaust body should be packed with silencer fibre wadding.  Makes the bike quieter and I think it improves performance.  The wadding deteriorates and/or gets soaked with oil over time.

[Nick]

My tube is just a rolled tube of gauze like -more hole than tube
Would I be better with a more tube and a bit less hole?

And how well packed and how much of the packing?
I just wrapped the gauze in exhaust wadding roll?

[hendred]

My "tube" is rolled up gauze too.  I just packed the space with as much packing as I could get in and it expands with heat to give a good fill.  I did get some perforated tube but decided not to use it because it was a bit heavy and I didn't think it would be a good idea to have it rattling around inside the silencer. I don't know enough about silencer design to predict the effect of changes to the exhaust.  A J Bell's book on two stroke tuning has a good chapter on silencer design, worth reading to get an idea of why the silencer is the shape it is.

[Smokey_Paul]

There are two different sizes.

Again I am waiting for Dale to sort the drawings so I can upload the new website

[Nick]

I have put one wrap of wadding on, as I was told by the bike shop I bought it from not to add too much.
The drawing shows the space full?

[Smokey_Paul]

Nick it's not an exact science I wrap the pipe then lockwire around the outside to loosely hold in place. If you over pack it can get compacted and just act as a peashooter it's just getting a good balance between silencing and backpressure / exhaust flow.

Wouldn't get uptight over it to be honest

[Nick]

Thanks, I am constantly looking for ways to improve it as I ride it every week with a Classic Club

[Nick]

I have done as you mentioned Paul and polished up the end cap all looks and sounds great.

[Smokey_Paul]