Modern Vespa

Hi everyone,

About halfway through a 2-hour ride today, I noticed my GTS sounded a lot louder than usual. So, having had a broken exhaust stud on the same bike last December and remembering how that sounded, I took a look at the exhaust when I got home and voila! -- another stud (the same one, in fact, as before) had been sheared completely off, making this the second time since I bought the scoot last August that one broke.

Any ideas as to why this keeps happening? I have the Moto Amore bronze muffler bearing installed--it's coming off when the bike goes in for the new stud--but other than that, I can't think of a good reason why the studs would be so prone to failure. Also, I've done my own tire changes, but I always torque the bolts to spec and in the recommended order (Torx, clamp, then header-stud-flange-nuts) and use plenty of anti-seize when sliding the muffler back onto the downpipe.

The only other thing I can think of is that the studs might be put under extra stress by the scoot bouncing over the bumpy roads here in Athens. There are lots of exposed joints, buckles, and other junk that are nearly impossible to avoid in heavy traffic,, and there are several spots on the country highway into town that have large ridges (~2 inches tall) spanning the entire width of the road that feel almost as bad as potholes to ride over. Could any of those be causing the studs to break?

One final thought--since installing the bearing voided my factory warranty, what would you guys think about me asking Moto Amore to help pay for the repairs? They do not mention anywhere on the website or on the product packaging that the bearing may cause the studs to fail. I know people using the OEM collar have had them break, but twice in the last 6,000 miles seems like more than average. I also know it was my choice to install it, but, if it is in fact the culprit behind the stud failures, the problems it causes are way more significant than what I would expect given the positive way it's marketed, so I don't think it's out of line to ask them to help. I know they're good people, too, so I feel bad bringing this problem back to them, but I feel like they should be willing to help.

Anyway, sorry for the long post. Thoughts, ideas, criticisms, advice--it's all welcome.

Thanks in advance!

-Scott

You have answered your own question. WTF do you think Piaggio still insist on rather expensive graphite impregnated steel mesh collars to allow the downpipe and exhaust to slide one against the other by up to 3mm or more.

I refuse to make comments about fools, money, and parting, but *OOPS*.

Thanks, Jim. Always a pleasure.

Have others reported this same problem after installing the Moto Amore bearing?

Yes. Check out these threads:

https://modernvespa.com/forum/topic16737?highlight=amore+exhaust+stud
https://modernvespa.com/forum/topic39383?highlight=amore+exhaust+stud

Here's one account of NO issues with the bronze gasket:

I don't remember now when I installed it (and it was a bitch to get it fit straight), but I would guess it was after about half the mileage I have now, so at about 12K miles. Since then, I must have removed the exhaust three or four times (always removed in one piece), and put another 12K miles on the scooter--with no issues anywhere.

I would, BTW, alter the installation order: fasten the exhaust with only the right of the two top torx bolts loosely inserted, then, after the header is firmly mounted to the engine, insert the other two and tighten all three torx bolts. That way, you will have a stress-free flange install and a conforming exhaust install. At least, this worked for me...

I would ask - what does one do when the rear tyre needs replacing? Where does the exhaust 'chain' get broken, at the manifold (deprecated by Piaggio) or at the downpipe/exhaust junction (welded shut by many bodgers)? Huh?

What the hell is wrong with using the original (and now re-designed) collars to allow the slip that is necessary with unsprung silencers? They last 12,000 minimum - OK, I do that twice over, my choice.

This has been a bit of a 'subject' on several threads recently. All I can say is that I see lots of folks trying to save USD24 and spending USD240 instead. Mugs. Muppets. Numpties.

DSSC, this is an 'Otto' marker.

Really, I wasn't trying to save money. I originally replaced the graphite collar because I didn't want to have to worry about it breaking on a long (1,600-mile) road trip I was planning to do. I honestly thought the bronze bushing was supposed to be more reliable and less likely to cause exhaust problems.

Edit: I would have taken the bushing off during the last tire change, but it wouldn't come off of the downpipe, which it somehow had latched onto instead of the muffler, to which it was attached during the install.

I had the original Graphite impregnated gasket failed on me twice before I went for the muffler bearing. Both times were before anybody touched the exhaust for any reason.

Screw that. I put the bearing in about 1500 miles ago. So far so good.

I understand why you would like some flexibility in that joint, but execution is everything and Piaggio didn't do so well on the GTS.

I'll accept the consequences if I get a failure, but the original gasket is a steaming pile of, well, you know.

P.

OK, understood, but those who espoused the bronze (brass?) solid joint were short of a few clues IMHO.

Did the designers ever think *why* the original collar was a graphite- lubricated one? Did they ever wonder why it gradually wore out? Did they ever examine exahust downpipes as to where the real wear existed? No, they looked at the dollars they could make from folk who only rode 3,000 miles a year and who thought every 'after-market' goodie was actually good.

The luckless buyers were in the most case NOT engineers by profession, and couldn't tell bull-shit from mustard.

Third-party stuff is in some cases, some circumstances, a very good idea - but normally staying with stock will keep you on the road for the longest time for the least expense.

Those with no cash to spare, and have to commute, PLEASE stay stock. Your beneficiaries will thank you...

So, you didn't read the instruction included with the Bearing? It doesn't go onto the muffler, it goes onto the head pipe. Driven deep onto the head pipe with Aluminum Anti-seize compound. Muffler goes over it (well lubed with more Aluminum Anti-seize. Align everything, then loosen manifold bolts and muffler clamp, jiggle to relieve stress, then retighten.

I don't care if people use the Bearing or don't, but any time somebody attempts playing mechanic, it behooves them to find out the proper procedure and follow it--regardless of whether it's mods or just normal maintenance.

P.

My mistake--I actually did install it onto the downpipe. Not sure why I thought it was the other way around, but I definitely did read the instructions, even if I have trouble remembering them.

Someone installed them though - and buggered it up both times it seems. The original ones were good for at least 6000 miles (and/or four exhaust on/offs) the new design should do double that in miles (exhaust on/offs are down to dexterity by the mech...). The design isn't bad, it's the lack of understanding of it by those who mess with it that has caused most of the early failure reports.

No problems with mine so far. I also did it the sameway as someone listed about. Bearing mounted to header first and header on only finger tight while I install the muffler. Tighten muffler first, then clamp, then header to head.

wow.

i have the original prototype of the muffler bearing installed on my 2006 GTS. i too, had a broken exhaust stud - sucktastic. but it now has [size=18]27K[/size]+ miles on it, and the exhaust stud shenanigans happened 19 k miles ago -

*shrugs*

Piaggio installed the first one, highly respected dealer the second. Again, I know enough engineering to know why the gasket might need to move, I just am not sure this is the best way.

If I do actually get a failure, I may go back to the brass bearing (or full weld-up) and float the muffler mount by making the bolt holes into slots and using shouldered bolts (or spacers). We'll see.

Still $40 here, and $40 there may be fine with most Vespa owners, but I'm a little too blue collar for that.

P.

After reading through all the threads that I could find using the advanced search feature on Google that have been posted on this forum, I could only find a few failures of the Moto Amore muffler bearing. I don't know how many Moto Amore has sold but from the interest that was shown in the product in the threads that I read, I suspect that it was quite a few. Internet forums are where most people go to report a problem. Conversely, few people ever post about products that work well with no problems. I think that the OP has an alignment problem due to the way the bearing was initially installed. I also understand why Piaggio used the graphite material for the original bearing/gasket but it's a shit design and it appears to me that there are a lot more scooters riding around with the Moto Amore bearing with NO problems than those with problems. I have one on my wife's GTS. She has only put about 200 miles on it since I installed the bearing but I followed the directions that came with the product and the assembly has NO more stress on it (after being tightened down) than it did with the old system (less the small amount of flex that was due to the graphite bearing). Unless I see a lot of failures of the Moto Amore bearing being posted, I'm going to leave it on the pipe. Time will tell.

Paul G.: I like your idea about shouldered bolts. Maybe, elongating the existing, round mounting holes on the muffler mounting brackets to an oblong shape and installing a small, hollow collar in those holes where each of the three mounting bolts passes through to the swingarm plate would also be a solution. This would allow the assembly to move slightly and relieve any stress that might occur from movement.

I thought about doing what you mentioned about, opening up the bolt holes on muffler mounting point, but didnt do it... But may do it on the next tire change. It would make mounting of the muffler a little easier when using the brass bushing.

I installed the MotoAmore bearing almost 18,000 miles ago. The bearing install in the downpipe was tight, but after dozens of silencer removals, I can say its paid for itself if I had to replace the graphite bearing every other time I removed the silencer.

No broken manifold studs, no leaking, no problems. I remove the silencer at the joint, and I always loosen the manifold nuts for re-assembly. Anti-seize grease is key.

Starr--you're probably right, and I bet I didn't put enough anti-seize on during both the last muffler replacement and the original install. I don't think I can keep it on their in good conscience, though, after having it break two studs, even if it was mostly my fault. *sigh* Back to the graphite collar...

this has been a major help for me and my local mechanic. My 2009 Super 250 had NEVER had any muffler work or anyhting removed but blew the graphite sleeve at about 2400 miles & less than 1 year of ownership. I think it will be best to replace with the oem sleeve. My local shop told me that it will be covered by warranty anyway. Thanks guys for the discussion on this.