Modern Vespa

Hi, Anyone running fat tires on a 8" bike? I run 4x8's and have never had a problem with rubbing for the most part. There are mild rub marks on my clutch cover that would indicate it rubs slightly over bumps, etc. However, I am thinking it is prudent to add a spacer, especially as SIP now offer them. SIP also offer new cogs/hub holders with longer studs, from 16mm to 21.5mm to allow for spacers, however they only offer this for the rear. SO, to my question: Is there enough thread to put a 5mm spacer, rim, hubcap bracket (about 2mm), and a spring washer on a 16mm thread. And the studs are the later 10mm, not the earlier 8mm.

Looking for opinions from people with similar issues, not just an opinion.

Cheers,
Simon

Is replacing the studs yourself an option, like what Ray8 just did on his VBA?

Hey there filmworker, can you post a pic of your set up? I assume you're running Heidenau K75's as they're the only "fat" 8" tire I know of.

I'm interested in going to a 4" rear tire myself, not so much for the width, but because those bad boys are a full inch taller than the 3.50-8's I'm currently on. Basically an upgear.

Unfortunately, the SIP spacer doesn't work on Supers due to the different style hub. If rubbing's an issue, I'd have to fabricate something.

a spacer that goes between the two rim halves would also give a wider rim...

Replacing studs is not really an option as I don't have a garage and my bike is out of the elements in a friends basement. I'd rather have all parts ready for an afternoon swap out.

I'm running King 4x8's. Never really had a rubbing problem, but there is slight marks on the clutch cover indicating that it does make slight contact over bumps. Not a black mark but a polished mark, so the tyre is not degrading. Still, it makes sense to space it

SIP make a 5mm spacer and a splined hub holder
https://www.sip-scootershop.com/en/product/spacer-rim-sip_83011000?q=5mm%20spacer
https://www.sip-scootershop.com/en/product/drum-brake-seating-sip-sport-rear_89574100
However, there is no option for the front besides changing your stud length yourself. So, my question is: Do I space out the rear only? Or, is there enough stud length on the stock studs to accommodate the 5mm spacer on the front?

What are the tracking issues like if you only space out the rear? A friend with experience tells me I won't notice a 5mm offset.

I think just about every old Vespa (including the "newer" old P200's have some sort of tire rubbing on their clutch covers. It all depended upon just which brand of tires were installed. I know the performance Zippy1's tended to make contact, than say a more stock tire profile like the S83. I've never worried about it myself. I just keep on rollin'.

If you only have rubbing on the rear than just get the set up up for the rear, and leave the front be? i am amazed that you still have clearance. i run a Heidenau with a spacer and really need that clearance maybe the Kings are a tad slimmer.

Aren't Lambretta tires 4 x 8's?

Thinking these look close enough to the Michelin S83's:
https://www.casalambretta.us/index.php?route=product/product&product_id=3747

Switched out the studs on an aftermarket rim that came with studs stupid short and crooked (see pics below).
https://www.scooterworks.com/Wheel-Hub-Stud-8-Rims--P3660.aspx

Looks like I might have enough stud length to add a 1/2" rim spacer and give a 4x8 tire a shot