Modern Vespa

M6 comes in 0.75, 1.0 and 1.25 pitches - all should be readily available. Grainger certainly stocks such studding.

I'm not so sure about that. I'm coming up empty (though I haven't checked Grainger yet).

Not seeing it at Grainger, either. I'm not sure M6-1.25 actually exists.

Huh. I could have sworn I spotted the studding at Grainger earlier. M6 x 1.25 nuts and bolts exist though.


Are we sure it's 1.25 we actually want?

My google-fu says they are as rare as hen's teeth.

Plenty available via Amazon and other outlets, even Walmart. e.g.:
https://www.walmart.com/ip/Flange-Cap-Screw-Flange-M6-1-25-X-30/160510267

What ARE available, as far as I can tell, are nuts and bolts, not all-thread rods or couplings - the pieces I need to fabricate a connecting standoff replacement.

I have gone back to ScooterWest to get them to confirm the non-standard M6/1.25 requirement since they originally suggested the build-your-own solution.

It's called a dado distanziale, or dado distanziale di montaggio del portapacchi, anteriore to be specific. It's like the one in the link below, but about 80mm overall. You can find these M6 × 40 Dado Esagonale Lungo in a lot of places. They are M6, and you can use two 50cc exhaust studs to fasten them together, then off you go.

this is similar, but a lot shorter.
https://scooterpartsco.com/021-vespa-c-801_802/spacer-for-front-luggage-rack-672320-p-37780.html

It clearly exists -- you can buy tap and dies in that size. But "plenty" is a big, big stretch.

I stand by my assessment of "rare".

If it's an M6 coupler the "standard pitch" for when none is specified is 1.0. The short spacer is also used in the 2023 GTS300 Rack. It is claimed that they, as well as my broken long spacer, are M6/1.25 pitched - this may be madness.

Rare (and unusual!) is fine. But not as rare as hen's teeth...

Well, he hasn't found any M6-1.25 threaded rod yet, so...

It would be madness indeed if the thread was M6x1.25. I could see a sense in using M6x0.75.

Do you have a metric ruler? Measure the distance between four five "teeth". This will be 4mm for a regular M6x1 and 5mm for M6x1.25.

Make your spacer out of a rod coupling:

https://www.amazon.com/Standoff-Hexagonal-Sleeve-Threaded-Fasteners/dp/B08YJQYD7L/

Chris from CLE

0.75 is a Fine thread - it's definitely not that.
M6x1.25 is PROBABLY M8X1.25, which is a "standard", but I'm going on what ScooterWest told me when I asked them for help... the same folks who suggested the solution was to buy the rack a second time. Go figure.
I have raised the "size" issue with them and I am awaiting their answer.
No metric ruler, not a metric country.

I really want to do exactly what you suggest, once I get the SIZE issue sorted.
M6 with no Pitch specified is standardized to 1.0, but (if you've been following this) you know that's not what "experts" have told me I need.

I repeat: Try a screw or nut out of a "M6 1.0" or "M6 1.5" bin, or whatever. Then you'll know.

Okay, wait. Just wait.

Metric is not exactly rare in the US. I have within my reach at my desk no less than 5 metric measuring devices -- several metric rules and a couple of tape measures that have both metric and inch.

But more importantly, you are working with metric parts on a metric bike. The backwards country we live in is irrelevant. You have metric parts that need measuring. Either get a metric thread gauge or (much simpler) get a metric ruler. It's not hard. I'll bet the hardware store near you has both.

Better yet, I'm virtually certain you can find a small, inexpensive metric ruler at Kinokuniya: https://usa.kinokuniya.com/stores-kinokuniya-new-jersey

Otherwise this is rapidly becoming a boondoggle.

I am so glad I didn't choose a Vespa front rack...

Similar sentiments! Though I do own a strap-down one (that I rarely use).

a. in 50 years of bike ownership, if I needed a part I just got that part; they were all IPB numbered and specs weren't needed
b. fabrication of a part by spec is, to me, therefore, an unnatural act - seems like something only vintage owners might need to do
c. the only part I would want to measure is the bit snapped off inside the frame from the Long Standoff; the Short Standoffs were not designed to go into the frame
so...
Yes, I agree I need to get a Metric gauge/ruler - shame on me for not thinking more Globally. And, btw, the Kinokuniya New Jersey store looks amazing...
Hey, I sympathize; I'm losing patients with this issue, too. I am hoping the REAL specs can be used to create something or that some other solution appears soon.

once I get the broken-off stub out of the hole in the frame... M6/1 or M8/1.25 are the choices I can try... although it would be nice to know ahead of time what works - because IF it's M6/1.25 I'm in trouble and will need a machinist

I wasn't sure the top clamps would clear the bottom for my full Vespa shield; the gap is small. But that story is in another thread...

Sorry, I was thinking the long and short spacers were the same except for their length.

I still maintain that they are.

I would like to think that - AND I will know for certain once the hole is cleared.
But you would think that, given how weird this whole "pitch" thing has been, I have every right to be afraid of screwing this up a second time. No pun intended.

You could be right. I should be able to confirm that when the hole is cleared next week... but if they are all M6/1.25... you know getting pieces to build something is not a good bet.

and I, finally, ordered one... I hope it delivers good news.

Not to be nosy, but what variety of thread gauge did you get?

https://www.amazon.com/gp/product/B00XUU0UMK/ref=ppx_yo_dt_b_asin_title_o00_s00?ie=UTF8&th=1
*
Jess, a funny thing has happened - I'm pressing ScooterWest HARD to confirm their M6/1.25 spec that they claim I can use to "build" a Long Spacer from "Hardware Store" parts because we all now know what a crock that is AND they've now gone silent on me. Feels like a "we can neither confirm nor deny" moment. No wonder they don't want to take tech support phone calls... *sigh*

👍 Or it's Friday and they've already fucked off for the weekend. ¯\_(ツ)_/¯

If their weekend starts on Thursday, when I last messaged them, that could be true. Is this a California thing?

One is arriving on Sunday! I let everyone know the news for the Short Spacer ASAP.
I think 0.75 (Fine) threads wouldn't be any good for "soft" metal spacers.

Why would Piaggio have made one bolt on the entire bike use a different pitch than every other M6 bolt they use on the bike?
It's a standard, everyday M6 x 1.0.
You could have taken the part you didn't break over to Home Depot or Lowes and verified this for yourself in about fifteen minutes. Here is a poorly taken photo of the bolt, screwed into a 6mm Yamaha exhaust nut, which is M6 x 1.0.

I agree in principle, and it's almost certainly M6x1.0. That said, it's not like Piaggio hasn't made similarly boneheaded fastener decisions for literally decades.

bolt depot has shoulder bolts
https://www.boltdepot.com/Metric_shoulder_bolts_Stainless_steel_18-8_(A-2)_8mm_shoulder_(6mm_x_1.0mm_thread).aspx


I would just buy a long bolt the correct length and then sleeve it with a spacer

You may be chasing something that doesn't exist.. See the metric thread size chart linked below:

https://fullerfasteners.com/tech/basic-metric-thread-chart-m1-m100-2/

Even if a M6 x 1.5 exists, this would be a good time to change to a readily available fastener size - there is something to be said for getting your parts at the local hardware store.

Once you remove the broken stud, re-tap the hole to 1.0.

Good luck,

Chris from CLE

I expect that you are correct, as I shall find out myself today! This raises two unanswerable questions beyond the scope of this discussion:
a. why would Vespa make a failure-prone part and provide no spares?
b. why would a reputable Vespa dealership insist that it has a pitch of 1.25?
M6 x 1.0 parts to build a replacement standoff are readily available.
I think this saga is winding down.
My thanks to all who helped!

I can answer that. Because Piaggio. I know that's not a very satisfying answer, but I expect that a small subset of people will just nod and chuckle here. Piaggio does many things well. But they also make stupefyingly dumb mistakes on a regular basis.

This particular mistake is likely compounded by the fact that mounting a rack to the front of a Vespa is not something that the Vespa was designed to accept, and so a half-assed solution was put into place. This is likely simple human error. I wouldn't read too much into it. I expect they are wrong about this, but I don't think there was any malice.