Modern Vespa

How often do you come across a broken exhaust bolt in the case and of course they drill another hole beside? This has to be my 4th one i have repaired. not exactly fun, but nice now.

Confession time...when I stripped the threads on my VBB's exhaust hole, I just tapped it up a size and went on. I figure I'll fill and tap it again eventually, but I've been saying that dive it happened.

It's been like that for probably ten years now without issue.

Timesert, helicoil or some other thread repair kit, would be my next step.
On the one Gick fixed, I'm still trying to figure out why the original broken off bolt wasn't drilled out and the hole fixed. Why an entire new hole in the wrong spot? With the size of the bolt, I would have used a center punch marked center and tried drilling it out with a reverse bit. If it had failed to come out I would have drilled it oversized for a thread repair kit. Maybe try a few easy out tools while drilling. My experience has been if a reverse drill bit doesn't get it out, either will an easy out.

My rough guess is that's where the replacement exhaust bolt landed, like someone did a dry fit with a Sharpie and went at it.

Hard to say, this is the way I got this customer GL project. Subject to water and outside storage, the bolts can seize up and the heads break when removed. Some heat in this area can get things moving TBH.

How come the old bolt turned to golden from the vapor blast?? Was it brass??

Brass. I don't know the history here, just showing the repair.

That design looks pretty lame.
The GS/SS is a different (better?) design. A long bolt goes all the way through an unthreaded hole in the aluminum and threads into a square captive nut on the exhaust bracket. If that nut strips, it's easily replaced.

My guess is that someone bolted on a brand new ill fitted Sito + exhaust, and that's where the bracket lined up the best. Oh wait, ill fitted and Sito+ in the same sentence is a bit redundant.

in all my years, and all the scooter-boy bullshittery i've done seen and had to deal with i've never seen this.

wallowed out, blowed out and redrilled, tapped up, hittin' from the back. yeah, all that. but i've never seen a side by side before.

but, as always my man. pretty work!

great job!

-g

I think 2 port motors are like this one, tapped, and all 3 port motors are also as you describe with a thru bolt.

Regardless, I'm with Greasy and at least the perpetrator gets points for originality.

That's correct. it's not necessarily better or worse, it's just what it is. When the exhaust bolts threads into the swingarm, i always use anti-seize grease on it; the factory never did.

This also appears on Widebody engines.

All performance exhausts use a bolt though the swing arm. Some manufacturers even say the threaded bolt may not be sufficient to hold it. Anyone have problems using just the threaded bolt?

It's certainly a lovely repair job, fair play to ya 😎

Interesting... The guy went to the trouble to drill and tap a new hole... how hard would it have been for him to drill out and extract the brass ?

Not since I re-threaded mine. I ran my Prima (JL Knockoff) pipe on my VBB for a long time with no issues other than ground clearance, but after a while, that dent just doesn't get any bigger

I've been running one for a couple years and it's still holding. I did bend the exhaust bracket so it met up flush with the swing arm bolt hole, but other than that, it's still working...