I haven't gone too stir-crazy, but having extra quarantine time has gotten me fired up about finally finishing a half-baked custom supermoto build I have been dreaming about for years. The aesthetics of this build are important to me, and although I will ride it and it won't be a complete show bike, I want the end result to be a conversation piece and something I am proud to show off, and I have a specific vision.

I am hoping to find someone who can sell me (or custom-machine for me) a new fork bottom/fork lug/fork leg foot with a radial caliper mount for a 47mm USD Showa. Something along the lines of these:












I don't necessarily need adjustable trail (like the black set pictured) and I am not particular about 100mm vs 108mm, either could work for me.

I am aware that there are lots of axial-->radial adapter brackets on the market, but I am hoping to find something one-piece. I am also aware that I could just go for another set of forks, like from a KTM SMR450, or an Aprilia SXV550, but the problem there is all the knock-on effects of having dug myself into this Showa 47mm hole....I would need to disassemble the other forks, send the fork parts out for coating/anodizing to match what I've started, get springs and valving for these new forks, plus all the problems with getting another fork to fit the custom triples I already have....not to mention front wheel, axle diameters, wheel spacers, brake rotors, etc, etc. Yes, it would be fairly cheap and easy to go with a different fork, but I would end up throwing away of lot of custom parts I've already sunk into this bike presuming I can use the Showas. Am I an idiot? Probably. Am I 5-10 years late to this party? Most likely. But I'm an idiot motivated to find a solution that doesn't involve ditching everything I've got into it so far.

I've contacted:

Race Tech
Goldfren USA
Extreme Riders Italy
SuperMoto Pro in Utah
CRFs Only

and so far all I have gotten is a big ol' goose egg. It seems that most of this stuff is discontinued.

Where else do you guys go for radial fork lugs or for custom-machined fork parts?

Slippery (Forum Supporter)
Slippery (Forum Supporter) GRM+ Memberand UltraDork
5/25/20 9:29 p.m.

How much do those things go for? That's a VERY tricky piece to machine. Either 5 axis, and still 2 operations, or quite a few set-ups to complete.

Do you have all the critical dimensions? 

Slippery (Forum Supporter)
Slippery (Forum Supporter) GRM+ Memberand UltraDork
5/25/20 9:35 p.m.

I spent the last 5 minutes looking at those things and think it can be done in a 4 axis machine, but there are at least 7 operations. Maybe a 4 axis + lathe and you still have a few mill ops. 

I am not really offering help as I see a lot of liability on that piece if all the dimensions are not correct, just trying to help you realize that it might be cheaper to go to a different set-up. 

If I was to quote that for a customer, two pieces ... you probably be looking at $1k each. 

I wish I could look at one closely to really be sure of what I am talking about. 

Thanks for the suggestions. It is an insanely complex part, with really fine threads on the inside of the fork lug to thread onto the fork tube. Supermotos are light enough they run a single large brake, almost always on left side, so as long as you can get an aftermarket radial-mount left designed to work with the stock right, and aren't changing axle sizes/offset (or going for adjustable trail) replacing both is a bit overkill.

Color me flabbergasted, but for once Faceballs came through and I have an arrangement to buy this used setup later this week:

It is for a Honda CRF255 (USD Showa 47mm) and my build is using a Suzuki RMZ250 (USD Showa 47mm) so I think I should be able to use the fork lug, the caliper, and the master cylinder. I will get a new rotor to match my hub and sell off the rotor, or try for a replacement Suzuki-pattern aluminum center rotor hub if the outer iron wear surface is in good enough shape.

I'll have to do some measuring of axle diameter and offset to be sure, but there is a chance I will need to change my right lug as well, or else machine a custom axle/axle spacer setup to match the Honda left lug with the Suzuki right lug. Thankfully, it looks like I can get an OE-style cast right lug for around $120:

https://www.suspensiondirect.com/shop/mx-parts/fork-parts/2-outer-tube-parts/d-axle-lugs

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