Oval carbon can sleeve.

[utopia]

I'm looking to rebuild the carbon can on my newly restored Sil Motor exhaust.
Can anyone suggest a source for replacement oval can sleeves in carbon fibre ?

I have found round section carbon sleeves which the manufacturers claim to be flexible enough to become oval when used with oval end caps .. but I'm sceptical.
It seems to me to be rather likely that the central portion of the sleeve will want to retain its original round shape.
In lieu of finding a proper, oval shaped sleeve, does anyone have any experience of using round carbon sleeves on oval end caps ?

I suppose I could use a different sleeve material which may give me more options to get the oval shape but for now I would prefer to replicate the original carbon sleeve because the original can, though a bit battered and previously shortened, does look good on the bike.

[Albie]

http://www.pjengineering.co.uk/products.php?cat=5

[Mr Gazza]

http://www.pjengineering.co.uk/products.php?cat=5

Anything here worth a look or a phone call?

I have in my mind someone in Lincolnshire who does just sleeves... It'll come to me. :scratch:

[bigredduke]

http://www.pjengineering.co.uk/products.php?cat=5

Anything here worth a look or a phone call?

I have in my mind someone in Lincolnshire who does just sleeves... It'll come to me. :scratch:

These peeps perhaps?
http://www.aa16.co.uk/

[Mr Gazza]

It was SP Engineering that I was thinking of, who are in Frome Somerset, near Lincolnshire! :rolleyes:
They don't appear to do just sleeves?
https://www.spengineering.co.uk/

[Grumpy]

These peeps perhaps?
http://www.aa16.co.uk/

Same guys I would suggest, localish as well.

[Ezio]

I have found round section carbon sleeves which the manufacturers claim to be flexible enough to become oval when used with oval end caps .. but I'm sceptical.
It seems to me to be rather likely that the central portion of the sleeve will want to retain its original round shape.


I had some replacement sleeves from SP Engineering for my ovals and they were indeed round when supplied. I even phoned them up to question the fit but they assured me that's how they do it.

Mine are quite short though so I see your concern about the centers on longer ones opening up.

https://i.postimg.cc/4yCVRV9y/SP-M900.jpg (https://postimages.org/)

[utopia]

Thanks for all your replies, chaps.
I'll have a phone round and see what the score is.

Ezio .. your feedback is very helpful .. just the sort of experience that I was looking for.
My existing can is about the same length as yours and although I intend to lengthen it a little, it will still be a few cm shorter than normal.
Maybe that will assist my cause.
Your can certainly looks fine in the pic.

I did find myself toying with a titanium sleeve which came up on ebay the other day.
But that was round too and the vendor suggested that it would easily adapt to oval endcaps.
So maybe I'm worrying unnecessarily.

[Dukedesmo]

The only experience I have with carbon cans is with Termignoni for both Monster and 916 (same sleeve size BTW) which are oval and I can definitely say that you would not be able to deform them in any way as they are quite thick and very strong/stiff.

Other brands maybe more compliant though...?

[utopia]

A short postscript, just to finish off the thread ....

I ended up buying the round titanium sleeve.
My thinking was that the titanium might be easier to work into an oval shape which would retain its finished form better than carbon.
Well, that was part of the reasoning anyway ... the other part was that it was only £30 posted !
At that price I thought it was worth a punt.
And anyway, the titanium will probably retain its cosmetic finish better in the long term than carbon would .. and as I have often said before, this bike is a definite keeper.

So, it arrived today and I can tell you that its only 0.5mm thick and weighs next to nothing.
It also deforms fairly easily to an oval shape while at the same time being stiff enough to resist returning towards round half way along the can.
So far, so good .. though I'll have to cut it to length and that might be a tad tricky.
But for now I'll have to leave it on the shelf 'til winter when I will sorn the bike, rather than disable it now during the riding season ... unless the temptation gets to me before then.

[350TSS]

You will really struggle to hacksaw it - Masking tape to provide a guide line and an angle grinder with a 1mm cutting disc or even a Dremel thin cutting disc. The spark shower will be entertaining.

[utopia]

Yes, I'm expecting to struggle.
Although I have got a bit more used to cutting titanium in recent years and I have in the past hacksawed through 15mm round bar ... but only with a sharp, new blade and, critically, a liberal dose of red cutting oil, which makes all the difference.
But I think my main problem will be holding it firmly enough to be able to get good cutting pressure.
I'm thinking maybe my giant toolmakers' clamp might be the key, if I'm hacksawing.
I do have some ultra-thin dremmel cutting discs that I will probably try but high speed grinding doesn't seem to suit titanium, in my experience .. and the heat might discolour the metal too.
I suppose if all else fails I could look into getting it cut by laser/plasma/water-jet or somesuch new-fangled witchcraft.
But in the short term I do quite fancy my chances at going all-in with a nice, sharp, fine-toothed hacksaw blade, some red juice and a firm, positive attitude.
Famous last words.

[BigOz]

An angle grinder will do the job without colouring the Ti as long as you take small bites don't dwell and let it cool. I'd tend to cut short of the line and work back to the line with abrasives (Roloc abrasive disks in an 90 degree die grinder is my weapon of choice) finishing off with lapping on a flat surface if the end needs to be really flat and square.

A manual hacksaw will work nicely on grade 1 or 2 (commercially pure) and just take a bit more dedication on grade 5 or 9. If your concerned with the tube flexing and preventing cut pressure how about making a quick wood buck to slide up inside the tube and support it. A couple of wood disks with some foam tape on the O.D. and a stick though the middle to go in a vice then slide on the tube and cut right over one of the the wood disks. Should allow you to support it without marring the outside too.

Might be worth mentioning 0.5 mm Grade 1 or 2 will cut using aircraft shears though the round shape might make that a tricky option.

[Mr Gazza]

I solve a lot of problems with woodwork, as you probably know. In fact I even work metal with woodwork tools.

So my approach would be to turn up a lump of wood as close as possible to the internal diameter of the sleeve, and push the sleeve over it, to hold the sleeve. Further lumps of suitable wood could be screwed on appropriately to hold the whole ensemble in a vice.
Tape could hold the sleeve onto the wooden mandrel.
Come to think of it, it might even be possible to part the sleeve off with a lathe if the sleeve were securely held on the wooden mandrel with suitable centres?

My first thoughts were to use a marking gauge off the end of the sleeve to ensure a nice even and square cut, I then thought that as the sleeve is only 0.5mm thick, that possibly a very sharp marking gauge might even go some way to cutting? Maybe a custom made gauge with a tungsten cutter installed? (Tungsten tipped glass cutter?)


Ha ha.. While I was posting Oz was thinking the same thing with a wooden buck...

[utopia]

Thanks for all your thoughts.

Yes, tbh I was pondering a wooden buck just now, while I was planting out my broccoli.
A few layers of thick plywood/mdf or summat.
I do also have a 2 inch length of massive ally bar, that is just a few mm bigger than the bore of the sleeve.
Turned down to a short plug, then maybe a slit in the end of the sleeve that I want to cut off and a ducting jubilee clip around the outside .. was a first thought.
BUT .. maybe with a plug inside, I could just grip the "waste" end (suitably slit) in the 4-jaw lathe chuck and hacksaw from there ?
I don't really fancy parting it off, or even spinning it at all in the lathe ... I envisage a crumpled mess.
Though I suppose I could mark the cut line nice and square by spinning it by hand, against a scriber.

You've got me going now.
I'm going to have to at least have a go at cutting it now, aren't I ?
But first I'll ponder your various other suggestions.
I may end up angle-grindering it.

Incidentally, I'm planning to rivet the sleeve directly to the end caps, ie without using straps.
I can't see the need for them with a titanium sleeve.
This was actually a small part of the reasoning behind getting the titanium sleeve .. it removes the cost of the straps as well as giving what I would consider to be a more secure fixing anyway.

Whatever the outcome, the ti sleeve only cost me £30.