So I'm trying to geek out and get stuff done while I'm still motivated, work and skateboarding have been a distraction from making progress.
I'm figuring out how to attach a second disc to the right side of the front wheel, not as easy as it seems. All the threaded adapters for ISO 44mm PCD discs and scootypuff 48mm discs have a right hand thread, so that won't work unless locked in place with a set screw or pins or something, plus buying or borrowing a 1-3/8x24 die from somewhere. Probably not the best bet, but an option if a clamp-style disc mount fails to work. The axial trueness of the threads is very important, might require fixturing in a mill and putting the die in a big ass chuck to get the disc to run true. All in all it's not a simple task.
The next option is to use a split shaft collar, drilled and tapped into the side for four of the six bolts. The only problem with that is there will be 1/2mm interference fit and with the rotor bolts to the wheel hub OD, this could be good or bad. It would keep the clamp from spinning, but weaken it and also need partial threads tapped into the OD of the hub. The main drawback of this is only using four of six bolts, which could cause warping or loosening over time.
I don't really want to weld or braize a mount to the magnesium wheel, seems extremely sketchy and a pain. I also need to offset the rotor outward about 5mm to make the caliper mounts symmetrical. That can be done with washers or a plate, but it would be cool to make the rotor mount flush to the adapter so it doesn't want to warp the hub.
I could machine an adapter that takes care of the offset and uses six bolts. There is the drawback that it still needs a positive mounting to the hub. It could be heated up and shrink fit to the hub with the paint removed, but will still require some sort of pinning to keep it from working loose.
I think I looked at this a long time ago and shelved the idea because it isn't easy at all. The bike doesn't really need the twin discs for braking power, it's just going to look sick and hopefully prevent heat warping and squeaks. This is definitely going to be something I hash out entirely before cutting metal, since it's ridiculous. There's another option for better braking - relocate the caliper out and use a larger single disc for more leverage. It doesn't even need that, the brakes work great. I'm just a dork, and I guess the challenge is interesting.
Another note is that the speedo magnet and pickup sensor probably need to get moved away from the rotor, probably won't be to hard by just moving them away from the center of the hub. The Sigma probably has a corroded coin cell battery in it anyways, hope it still works.
If any of you guys have had good success mounting an ISO 44mm PCD rotor on the right side of a hub, especially a 1.5" diameter hub OD, please let me know.
I'm posting these ramblings here as notes and motivation to get this moving. I know this type of stuff is dry as dirt, but these sticky details are what forums are all about IMO.
After I get my BMX back running with its new parts, this bike is up next to get resurrected, so stay tuned this spring and fall for updates.
I'm figuring out how to attach a second disc to the right side of the front wheel, not as easy as it seems. All the threaded adapters for ISO 44mm PCD discs and scootypuff 48mm discs have a right hand thread, so that won't work unless locked in place with a set screw or pins or something, plus buying or borrowing a 1-3/8x24 die from somewhere. Probably not the best bet, but an option if a clamp-style disc mount fails to work. The axial trueness of the threads is very important, might require fixturing in a mill and putting the die in a big ass chuck to get the disc to run true. All in all it's not a simple task.
The next option is to use a split shaft collar, drilled and tapped into the side for four of the six bolts. The only problem with that is there will be 1/2mm interference fit and with the rotor bolts to the wheel hub OD, this could be good or bad. It would keep the clamp from spinning, but weaken it and also need partial threads tapped into the OD of the hub. The main drawback of this is only using four of six bolts, which could cause warping or loosening over time.
I don't really want to weld or braize a mount to the magnesium wheel, seems extremely sketchy and a pain. I also need to offset the rotor outward about 5mm to make the caliper mounts symmetrical. That can be done with washers or a plate, but it would be cool to make the rotor mount flush to the adapter so it doesn't want to warp the hub.
I could machine an adapter that takes care of the offset and uses six bolts. There is the drawback that it still needs a positive mounting to the hub. It could be heated up and shrink fit to the hub with the paint removed, but will still require some sort of pinning to keep it from working loose.
I think I looked at this a long time ago and shelved the idea because it isn't easy at all. The bike doesn't really need the twin discs for braking power, it's just going to look sick and hopefully prevent heat warping and squeaks. This is definitely going to be something I hash out entirely before cutting metal, since it's ridiculous. There's another option for better braking - relocate the caliper out and use a larger single disc for more leverage. It doesn't even need that, the brakes work great. I'm just a dork, and I guess the challenge is interesting.
Another note is that the speedo magnet and pickup sensor probably need to get moved away from the rotor, probably won't be to hard by just moving them away from the center of the hub. The Sigma probably has a corroded coin cell battery in it anyways, hope it still works.
If any of you guys have had good success mounting an ISO 44mm PCD rotor on the right side of a hub, especially a 1.5" diameter hub OD, please let me know.
I'm posting these ramblings here as notes and motivation to get this moving. I know this type of stuff is dry as dirt, but these sticky details are what forums are all about IMO.
After I get my BMX back running with its new parts, this bike is up next to get resurrected, so stay tuned this spring and fall for updates.
