We got a great email the other day from Victor Voris regarding the GTS exhaust gasket and some of the other issues we’ve been talking about. Victor’s been running Big People Scooters in Seattle since 1989, and was one of America’s most respected Vespa experts during Piaggio’s absence. When Piaggio returned to the U.S., Victor’s Vespa of Seattle was among the first dealerships to open, and one of very few to be run by someone with extensive scooter experience. Since then, both shops have flourished. I respect his opinion greatly, and like others, he feels modern scooter repair is best-left to a factory-trained technician:
There has been a lot of miscommunication and misinformation about the GT/GTS exhaust gasket and packing problems. The first thing to know about the problem is that you are NEVER to take the pipe apart. in all Piaggio shop manuals, as well as at any factory school, you are clearly told this. The reason that the pipe has this graphite one-time-use packing is that the header pipe is made of a different metal than the rest of the exhaust (I believe the header pipe is titanium). Because there is a joint there, and a clamp that can come loose, the torque on the bolt is to be checked as part of the routine service, as it can loosen over time.
In our shop we have seen exhaust systems come in that the customer has beaten apart, which will never go back together and seal, even with a new packing installed. It is by no means a design problem, any problems are coming from incorrect maintenance or repair. PiaggioUSA requires that their dealers have factory trained staff and offers training to their dealers free of charge. It is unfortunate that not every Vespa shop in the country has only factory trained technicians working on their scooters, but that is the case. There are countless other things that home-repair people and non-certified shops are doing that can cause huge damage to a modern Vespa motor. A common mistake we see all the time in the shop is the re-use of the one-time nut on the variator. If this nut fails, one of the many things that can happen is damage to the crankshaft, and installing a new crank is not fun for anyone. All of the factory shop manuals and workshop manuals are posted on Modern Vespa , and anyone working on their scooter at home should download these and read them. I am planning to offer tech classes at Amerivespa this year, and am trying to get Piaggio to send a technical representative as well.
It’s common in scootering (especially on the internet) for a scooterist (often me) to insist he knows more about scooters than the people who make and sell them. Sometimes they (I) do, but there are certain people I’d never dare argue with, and Victor is one of those people. I do, however, look forward to rebuttals.
So in summary… admittedly the pipe does loosen on its own and can blow out the gasket; Piaggio acknoledges that dangerous consequences can occur from a reused or blown gasket including the possibility of catastrophic brake failure or other. One can reduce the risk of damage by paying someone else to check torque periodically who may or may not be “factory trained”. It’s not a design problem because they intentionally made it that way. Finally, owners should just accept it because Piaggio won’t do anything about it anyway.
Several people on Modern Vespa didn’t do anything with their exhaust pipes before having the gasket blow out.
What possibilities does this leave if it’s not a design flaw? 1) Piaggio has some flaw in assembling the pipes. 2) Vespa dealers are messing with the pipes during prep or on the showroom floor. The first option seems more likely than the second.
No matter what the reason, the initial gasket blow out seems to happen before the exhaust is removed for maintenance or tire changes. Several riders have needed their gaskets replaced at what appear to be regular intervals. If the replacement gasket fails in about the same time as the original, and the next replacement does as well, that strikes me as a design flaw.
The question is (and this could be answered by anyone willing to dig through the service manuals): Does the dealer service manual clearly state that that joint should never be disassembled, and specify that it should be checked at given intervals as part of regular service?
A cursory glance at the workshop manual seems to indicate that the pipe *is* intended to be removed *with* the header as Victor points out. As far as torque, parts *do* vibrate loose, any vehicle service manual (even old Vespas) specify that at certain milestones you must make sure certain fasteners are torqued to spec. I think Victor is simply trying to make the point that torque specs and maintenance requirements for vintage Vespas are pretty damn forgiving, while modern machines require a far more precise going-over. If the original manuals do *not* specify that this gasket must be checked, the service bulletin does, so they’ve (legally, if not ethically or practically) covered their bases, even if it was after the fact.
That said, it still sounds like it’s more prone to failure than your average gasket, and *if* it is a frequent problem, and *if* the part is hard to get, Piaggio could be more accountable, especially in gasket failures where scooters followed the proper service schedule and service was performed by the dealer. Whether it’s a matter of service personnel being improperly trained or a matter of a defective or poorly-designed part, you expect more from a $5000+ scooter and the company that makes it. American scooters have a pretty cushy life for the most part, and the GTS hasn’t even been out that long, so even a dozen or so instances of failed gaskets on properly-maintained machines would seem to indicate that it’s a problem that needs to be addressed in more detail. Which is why the internet is beating it to death.
“even a dozen or so instances of failed gaskets on properly-maintined machines would seem to indicate that it’s a problem that needs to be addressed…”
Did you count *all three times* that the gaskets failed on the GTS I sold Bobo to take on the ’06 Cannonball? That machine had never even been looked at by anybody other than a certified Vespa dealer before the first gasket failure.