This topic comes up a lot in the motorized bicycle world. The only mass production 1" threaded suspension forks are from RST, and not "real forks", basically just spring and elastomer jobs that work, but don't have any real damping.
You can convert your 1" threaded bike to take 1 1/8" threadless forks, but you will need probably 2 headsets to combine, and will need a threadless stem to match the fork. Call Lynne at www.custommotoredbicycles.com
if you really want to do it without welding a new head tube on your frame.
Originally Posted by fatdaddy
It's not the fender, it's the cheap little tin tabs they give you to bolt it up with. They are usually pop riveted on and can break or just plain come loose. I usually remove them completely and make my own if I run with a front fender. After I make a tab out of better thicker steel I use a small bolt to attach it to the fender, Then peen it down like a rivet. Then lock washers and locktite to install. The rear fender is important also, just not as critical as the front.
Anyway, got my cheapo retro speedo in and installed. I'm finally almost finished with my bike. Well, as far as one can be with a build. There are always things that come up that make you want to change things around. I was looking to put drum or disc brakes on the front, but one was really expensive, (disc,) and the other, (drum,) was a LOT of work. (rebuilding and lacing a wheel.) So I got rid of the calipers and put on a set of cantilever forks. I got it all together last night and now I just have to tighten everything up and take it for a test ride. I found a set of Schwinn forks with cantilever bosses at Fabers Cyclery that are almost the exact copy of my huffy forks, so I kept the fat fork old school look. Was hoping to find some suspension forks with a 1" head tube and cantilever bosses but everything today is 1 1/8". Oh well, It's together now. LETS RIDE.