Mounting Wheels off one side


Using Coaster Bicycle Wheels

  1. I have used rear coaster (pedal back to brake) wheels for the 2 front wheels as they have a larger axle than most normal bike front wheels. I've noticed that the 'free style' bikes especially have these larger axles on their front which would do fine and may look slightly better if you can find them. An added bonus with these is they often have more than a normal amount of spokes as well as a thicker spoke which helps with the sideloads a trike puts on the wheels. So if using the coaster wheels first prepare the wheels in this way. Grind down the torque arm so that it can act as a washer. Referring to the sprocket diagram remove the sprocket and either grind it down so that it acts as a washer to hold the dust cap on or find a second snap ring to replace it. The front axle is a hardened steel bolt replacing the normal axle and can be purchased from the local hardware store for about $2 each. There are different grades of hardened bolts. As I understand it you can 'read' the grade by counting the scribes on the bolt end. The scale is up to 10 (being the hardest) and 2 marks are subtracted from the total count. I use ones marked with 3 scribes which is still quite mild but they haven't bent yet. I'm told not to go too hard as they will be very strong in tensile(stretching) strength but also brittle so could sheer in use.( I've tried normal bike axles and some do bend.) Referring to the diagram the inside cone (cog side) is drilled out. This isn’t as easy as it is to say as the nut is hardened an wore a drill quickly. The following will sound very crude but it does work. I drill the thread out waiting until the drill and nut gets red hot before pushing it through. If you wait like this it is easy work but will pretty well destroy the drill bit. It doesn't really matter if the nut is damaged slightly as on that side there is another set of bearings so it doesn't matter if it doesn't spin freely. All of the original nuts, hub insides and axle are discarded and a nylock nut is used on the outside of the wheel. The bolt axle then passes through the (as per the diagram) right drilled out cone nut, bearing, hub and then screws into the brake cone with the nylock nut holding the ground down torque arm against the brake cone.The nylock nut is needed at least on the left side as the torque arm nut will tend to unscrew with the forward motion.

  2. Sat, 17 Mar 2001
    From: Tom E Arnold
    Subject: Grade 5 bolts

    I am currently contemplating construction of a tadpole (for practice before building a Locost sports car from plans) and would like to clarify one item I found on your construction site. I worked for 22 years at a steel fabricating firm founded by a former sports car racer, and am very familiar with the subject of high strength fasteners. What you say is correct but incomplete. There are three grades of steel fasteners in common use in the US, 3, 5, and 8. Standard stainless fasteners will not be much stronger than grade 2s, but will be tougher, and of course rust-resistant. The grade 9 and 10 and high strength stainless fasteners are normally available more from industrial fastener houses than from hardware stores. An excellent reference on industrial hardware is They are rarely the least expensive source for anything, but they have an extensive stock and informative catalog on line. You are exactly right in recommending Grade 5 fasteners for load-bearing. We used them in overhead lifting for the exact reason that altho they are not ultimately as strong as Grade 8s, thhey would bend rather than break.


  3. Date: Thu, 10 Aug 2000
    From: Clint Everett
    In your description of adapting coaster bike wheels for use with stub axles on a trike,  you talked about destroying a drill bit each time you bored out the hardened steel bearing cone. Here is something that worked well for me.
    Buy a cheap 1/2 inch masonry bit (the shortest length you can find). The body of the bit is not special, but the little cutting blade brazed onto the tip is Tungsten Carbide.
    Patiently, on a fine grit grinding wheel, polish the leading edges and ends of the cutting blade to a sharp profile, with the leading edges slightly higher than the trailing edges.
    Clamp the bearing cone in a machinist's vise and, at the slowest speed your drill press will turn, bore out the hole. It will get hot, but the Tungsten Carbide will cut cleanly without sacrificing itself.
    I have drilled out four cones and four cups with the same bit and it looks like it would do several more without resharpening.

  4. From: Ian Johnson
    I've enjoyed your pages on recumbent trikes and wanted to pass on a tip that I am trying out from a friend of mine who is a welder and does a lot of mechanical stuff. For the front wheels on a tadpole his suggestion was to use rear coaster bike wheels, but instead of drilling out the cones and such, was to get rid of all the guts and to get two sealed bearing sets that would just fit into the drum and fit against the shoulder. My bike isn't finished yet, but I have the wheels and the bearings and I thing that it will work fine. The bearings are a bit loose in the outside fit, but the shoulder is on an angle so the bit of sideways pressure from the nut on the axle will perfectly center them. He has tried this before on a project he once did and it seemed to work quite well. I'll send pictures or a url when I get things set up.
    Ian Johnson
  5. From: "Robert Stein"
    Subject: Re: [trikes] Front Brake Recommendations?
    Date: Sun, 29 Apr 2001

    Which type of front brake (manufacturer and model) do homebuilders recommend for the front brakes for a homebuilt trike? My WizWheez has Sturmey Archers but I am not sure about availability for a homebuilt project. Would Sachs VT5000 be the best solution for front brakes. Thanks for any tips.

    Sachs VT5000 are just fine. The only "thing" remaining is the modification to stronger axles.

    Very simple (if a lathe is somewhere near). 1) remove the original axle 2) remove the cups 3) the remaining holes are aproximately 27.7mm (or something like that) machine them to 28.00mm (so that "6001" sealed bearing fit inside snuggly) 4) drill a 16mm hole through the hub 5) after measuring the distance between the bearings, prepare a 12/15mm dia (hole/out) distancer that will keep the bearings in the middle and one 12mm long piece that will fit between the inner bearing and the brake holding plate 6) Drill a 12mm hole in the brake plate 7) put the pieces together and pull through a 12mm axle 8) done...

    The "6001" bearings should have exactly a 12mm hole and 28mm outer diameter. Some mopeds use 12mm axles (cheaper than custom made)

With Disk Brakes

Also see what's on the IHPVA text page.


Thursday, 29 January 2009