Muffler Suspension

Glad you opened this exhaust suspension thread as I've
not figured out what to do on Ms Peel 2 >1 > long megaphone.

You really should create an accurate power unit motion graphic.
I LOL on first seeing the moving Commando life forces image.

I've measured the motion at all 3 points and find that
its example of quantum in-determinacy entanglement
in the macro world existing in more than one mode at once.
This helped me configure Peel's tri- linkage iso stabilization.

Basic motor motion w/o road loads > 66% up/dn - 33% fro/aft.
Rear iso is a pure pivot with front iso bouncing up/dn ~1/16"
either side of its rest position at steady engine speed.

On blip ups, front motion is mostly a jump up and slightly back
by another ~1/16" for ~3/16" total off rest position, and
~1/16" fro/aft total.
Rear iso also slightly moves on blip ups ~1/32" fro/aft from rest

With road loads and tire thrust over laying on pure
engine oscillation, I see additional fro/aft front and rear iso
motion by another ~1/16". Seen by smeared oil grit/grime.

The witness marks left by entangling all the loads shows
an over all egg shaped at front that the slightest bit
bent in an arch convex forward.
The top steady shows about half the size motion 1/8"
total with most to the trace as fro/aft arc.
[Late Gerry Bristow gave me his flat plate steady with marks]

The rear iso trace shows mostly circular 1/16" OD orbit slightly
smeared more fro/aft that up/dn.

The front iso traces out what looks like the classic
planetary atom symbol or planet Saturn/egg with two sets
of rings,
- a vertical egg ~3/16" with two rims standing proud of the
egg shelll, vertical rim more prominent than equator rim.
Here's photo trace that's hard to do with marker
and bike vibrating and only two hands to work
throttle holding clamped pencil still.
[Tag URL to enlarge detail]
http://image50.webshots.com/50/1/2/46/5 ... pYV_fs.jpg



I've 2 plans to try,
A- to fab a twisted plate 45' to hold weight more in compression
on the rubber yet allow up/dn and fro/aft compliance.
B- to suspend by springs, which I've had to do when rubbers
on hand all torn up.

Me and my Cdo buddy Wesley on unpaved paths find that after
a few rubbers set fail headers crack a couple inches from ring 'nut'.
Also peashooter baffle break lose to rattle clang, so we must
trap them still by external bolt mostly out of sight or buy more
to often.

Oh yeah, I also grind a waist in the rubbers for more compliance.

hobot

hobot said:

You really should create an accurate power unit motion graphic.
I LOL on first seeing the moving Commando life forces image.

hobot

Click to expand...

I have no interest in making it accurate. There is more benefit to illustrating by exaggeration. But as I believe you noted, there is less movement at the rear iso (as expected) and more of a pivot motion. That is why I proposed a pivot mount for the mufflers. Ideally they would be mounted to the cradle be the leverage from a stock system might be too great.

You should try keeping 'S' exhaust systems on and working.

Dave
69S

You know if you guys are trying to make these bikes fool proof, Cool it!!!! I like working on my Commando. LOL LOL LOL. :mrgreen: But you guys do have some great ideas.

DogT said:

You should try keeping 'S' exhaust systems on and working.

Dave
69S

Click to expand...

I think I'm about to discover those joys with the "SS" pipes mated to some Emgo wide-mouth Dunstall replica megs. (They look like what was once described as "Blooey pipes")

Danno said:

Your computer simulation is a bit inaccurate

Click to expand...

Oh, I think swooshdave is spot on....well, in the spirit of Monty Python.

ludwig said:

I took the oportunity to take some better pictures , showing the supports relative to a STD engine craddle.

Click to expand...

Shouldn't the supports be anchored at the cradle with at least two bolts each? Otherwise, I would think the two single bolts would quickly be subject to looseness from vibration...

ludwig said:

Since I have to take the mufflers off anyway ,
( pre-season check revealed a worn inlet lobe : soft cam , despite deer oaths of the vendor , so I have to take an otherwise perfect engine apart after
35000 km ..grr..!)
I took the oportunity to take some better pictures , showing the supports relative to a STD engine craddle .
As you can see , either the craddle or the supports must be allongated .
They are not symmetrical because The LH has to clear the chain .
The material I used is not alloy or iron , but steel , to better resist vibration .

Click to expand...

Great pictures. Sorry about the engine.

Those look like quite the contraption, but they do what they have to to. Nice job.

Very nice work Ludwig, Do you do all the fabrication yourself? And it looks as if your mufflers are stainless? Where did you source those? Thanks for the photos, Chuck.

ludwig said:

Of course !! I am not THAT stupid ! These pics are for demonstration only . These supports are made to fit the craddle I use , not a STD craddle.

Click to expand...

Whew! O.K., thanx.

Here is a picture of my muffler mount



It bolts onto the transmission cradle with two 1/2" bolts and one 5/16 bolt that also holds the oil filter on. I didn't have to modify the cradle at all. I cannot use a center stand though. I don't have one anyway.

I haven't riden this bike yet but it looks like it should work well. The mufflers are held very ridgidly. It is not that much different in function or design than the other simillar one shown in this topic. I thought that someone else must have tried this. It was very easy to make. For me it was easier to make this than to aquire all the correct bits. I have mounted two pea shooters on it and the bracket is barely visable. The only thing that looks wrong is there is nothing connected to the ends of the Z plates.

Nigel

Here are some pictures of my 850. I am trying to finish it for Lumby. It has the special muffler mount shown in the previous message. It is really hard to see in these pictures. The mufflers feel really solid. Hopefully there will be no resonnances. I think it should be better than the stock system.

This bike also has an unusual kick starter. It looks like a Japanise one. No one here seems to know what it is, even the experts. It mounts on a much smaller spline than Nortons usually have. Where does this small spline come from? Is it a special one off that someone made? Is it a standard Norton part? Did someone make a batch of these so that Honda kick starters could be used? It seems quite nice as long as it doesn't break.

I have used some RD 400 Yamaha wheels that I was given. This is really easy to do. The Norton axle fit right in. The rear sprocket is only out of line by .040" if the wheel is perfectly centered in the frame. I offset the wheel .020" to the right, that way the sprocket is out by .020 and so is the wheel. This is as accurate as you need. The Yamaha disks are the same size as the Norton ones.

For me Black and Gold is the best for a Norton. How do you guys like the bike? The tank is one of the ones sold on E bay by neuxstone. He makes them too order. I am very pleased with it. It is very high quality.

Looks like it will be pretty sharp once it's finished.

It screams for some custom Z-plates, especially as you won't have to worry about a passenger.

Anyone else make a cradle mount exhaust bracket?

concours said:

Anyone else make a cradle mount exhaust bracket?

Click to expand...

exhaust-brackets-the-cradle-who-done-pics-please-t13845.html

Nicely frabricated muffler mounts Tricatcent/Ludwig & thanks for taking the time to post the photos of them, gets me thinking about some of the modifications I'd like to do to my bike when I get back home to it. I have a set of Interstate pipes with the balance tube header that I got off of e-bay for a hundred bucks last year and since it is complete I'm going to use it for a while, however I imagine I will be replacing them. :wink: