[Megadan]

Ok, so as an update now that my new, different, studs arrived.

Honda Part Number 90128-361-000 for the MT125 and XL175.
These are a viable alternative to the factory sprocket studs, in my case they are still a teeny bit loose in the bushings on the hub, but way better than the factory ones.

I whipped out my digital calipers to do a little measurin'.

OE Hawk Stud. Threads - M10. Pin side - 8.8-8.9mm diameter. Flange thickness 2.7-2.8mm. Each stud had .1mm of variance from part to part.

Honda 90128-361-000 Stud. Threads - M8 (uses the smaller set of holes on a JT sprocket). Pin diameter 9.2mm. Flange thickness 2.8mm. Consistent across the board within a few thousandths of a mm.

Wheel hub bushing sleeve the pins go into had a lot of variance to them. but overall they averaged out to 9.3mm. From the research I have done on these bushings, they should be 9.2mm, so this would explain why my factory studs were a hotdog in a hallway. .4 to .6mm of gap. Now I have about a tenth of a mm of gap with the new studs.

With the sprocket installed over the new pins and just the snap ring the sprocket with no nuts on the studs has less play than the OE studs had with the nuts torqued down and loctited. This makes me confident enough in this setup to ride the bike once they are tightened down. I think the variance in flange thickness and pin side diameter combined with the large difference in I.D. of the bushing sleeves just created a perfect scenario for play. I have total confidence in the M8 stud size to hold the torque/power of a CG250 engine, although I would prefer to retain the larger M10 sized threads. Given the quality of the metal the Hawk OE Studs are made out of, I am far more confident in the strength of the Honda studs, even if they are a bit smaller. For my own peace of mind I do plan on using Loctite retaining compound on the studs, which is the main reason I haven't fully installed them yet. I just need to figure out which one is best for the application. Either 638 or 680 are the front runners, because of their ability to fill larger gaps (up to .25mm and .38mm respectively), but this will come at the cost of high tensile strength which can make potential stud removal later a pain...