Exhaust brackets snapping - standard type expansions

[immylam]

Just back from Scarborough and my ancilloti exhaust snapped at the main top bracket ( the snapped off bit still bolted to the scooter. This is the 2nd rally in a row this has happened at - brid at the end of last year an indian big bore clubman snapped. The big bore didn't seem that good quality but the ancilloti was far sturdier. Now have I just been unlucky is the quality poor or can there be something causing this? There doesn't seem to be any unusual vibrations more than normal. I have just gone back to standard looking type expansions and wonder if this a common fault and what can be done to reduce the chances of it happening.

[psychedelicropcircle]

Make sure your exhaust is not touching the chaincase or anywhere else for that matter it'll shake it to death. It would be cheaper to buy an expansion (sharks fin) bracket and bolt it to the clubmans sharks fin. You may have to put in longer bolts.

[purple_pill67]

Bgm have slip joints on u bend,adjustable shark fin bracket, mounting point underneath and on the tailpipe.
Done about 5k on mine no issues, the sloped af one i had before did about 700 miles....

[Donnie]

Are you runing a mugello?

[onthelam]

Could it be the installation procedure. Two failures in a row seems unusual?

I say this because i had a guy, not Lambretta , who claimed his exhaust was the wrong model. Because he bolted up the muffler first and then said the front pipe wouldn't fit.

[immylam]

Yes , I am running a mugello...

[Donnie]

hmmm in that case how well did the exhausts go on, there are / were batches of mugellos where the exhaust port was modified effectively giving the whole cylinder a larger than normal diameter. This had the effect that all standard eg clubman exhausts wouldn't fit properly to the point on mine where I have to cut off the swan neck bracket and reweld it 5-10 mm backward allowing the exhaust to sit properly and not under tension.

MB actually make a specific swan neck for these mugellos for some of their exhausts!

Depending who you talk to, this is either a flaw in the design or a "performance enhancement"

Do you remember which mugello it is?

There was the first ones way back about 2002 that never came with a head so you had to reprofile your old one.
Second one was with a head and had a boost port
Third had a head, boost port and collets to centralise the head like in this link http://www.lambrettaspares.com/images/p ... G_6062.JPG see the way the stud holes are smaller in the recesses
Fourth and current version they did away with this and instead have a cylinder head that attaches seperately to the cylinder as well as the studs. very recognisable with the 8 hole head gasket.

The one with the collets is the one I have and i suspect you may do too.

[immylam]

Thanks Donnie , that looks like what has caused the problem , now to find an exhaust or welder that can rectify it.

[ArmandTanzarian]

My ancilloti snapped three times before I finally gave up repairing it and bought a BGM