- Rear-axle STRONGER:
If you want BIG & FAT TIRES (Big Foot) then use an extra strong rearaxle. The rearaxle tube needs 3 (-4)
mm thickness instead of 2 mm OR 40-50 mm diameter instead of 32mm. Minimum thickness for the rearaxle is 2
mm. Also change M12 into M16 (bolts and ballbearings !). The M12 bolts can bend.
You may also have to change the tube-in-tube connection by a bolt connection, simular to the wheel attachment
on the rear-axle. That connection is more stiff.
- Rear-axle WIDER/NARROW:
If you NEVER want to make wheelies but want to set the speed record then increase the axle wide from 950 to
1050 - 1250 mm. If you want to make MANY easy wheelies go for 940 - 925 mm. If you intend to use Big Foot
wheels you may need a 1150 - 1200 mm wide rear-axle for extra elbow (yours) space.
To return to the original geometry of the buggy you need to increase the length of the frame tube or
experiment with the angle between frontfork and surface (caster).
- Balhead (downtube):
The square tube must be at least 2 mm thick. For wheelies and Big Foot wheels, 1.5 mm is to WEAK !!.
- Frame Tube:
A wider rear-axle (more then 950 mm) requires a longer frame tube to return to the original geometry.
(Rear-axle increased from 950 to 1200 mm requires 240 mm part to be increased to 303 mm. Check drawing.)
- Steering more STIFFER:
At high speeds on washboard or rough beaches a more stiffer steering is more desirable. While for fun and
stunt purposes the smooth feathery steering is wanted.
- Replace the ballbearings in the downtube by teflon rings of the same size.
- Replace the inner 55x20x12 tube by a 55x24x12 one, for more contact with the teflon ring
- Tighten or loosen the 8 mm bolt, on the front fork, for a more or less stiffer steering.
- Balhead & Frame Tube connection STIFFER:
Instead of one 8 mm bolt (see photo) use two (2) 8 mm bolts as follows:
- Add to the downtube extra holes, with diameter of 10 mm, at 25 and at 175 mm.
- Drill the 8 mm hole in both U-shapes at 25 and 75 mm. And NOT at 50 mm !!.
- Weld the both 8 mm bolts to one U-shape.
- Weld each U-shape to the tube in the middle of the U-shape.
- The whole frame RIGID (one piece):
Instead of one 8 mm bolt use two (2) 8 mm bolts as follows:
- Add to the downtube extra holes, with diameter of 10 mm, at 25 and at 175 mm.
- replace the U-shapes for a square tube (3 mm thick)
( inside measures same as outside measures of downtube )
- Drill the 8 mm hole in 2 sides of the square tube at 25 and 75 mm. And NOT at 50 mm !!.
- Weld the square tube to the frame tube in the middle of the U-shape.
- Instead of the tube-in-tube connection with the rear-axle weld the frame tubes to the rear-axle.
- Seat (photo's):
Replace the red seatbelt webbing by dacron fabric as used for a sports bag. You get a full surface instead of
the fish net feeling... It gives extra protection against water.
Check the photo. Note there is a fourth seatbelt with loops, close to the rear-axle, which is tightened
between the frame tubes. This results in extra support for your back. You will feel the difference with a
"fish net" seat. But I have not tested it yet, so I don't know if it is good enough. I estimate that
something is neede to prevent the 4th loops of slipping down to the rear-axle and to increase support. Check
the plan for a comfortable seat with integrated back and side support.
- Front Fork with speedometer:
T.b.s.
Shopping list Materials:
- Stronger rear-axle (no drawning):
1x 950 mm tube dia. 45x2 mm,
2x 45 mm rod dia. 41 mm, full,
2x 90 mm tube dia. 30x2 mm.
Optional: 2x Bolt M16 - 100 mm with spring-ring, (think of the ballbearing in the wheels !)
- Wider and stronger rear-axle (no drawning):
1x 1200 mm tube dia. 45x2 mm,
Rest same as above.
- Balhead:
1x 456 mm square-tube 32x32x2 mm,
1x 75 mm rod dia. 37 mm, full,
2x 20 mm rod dia. 16 mm, full,
1x 55 mm tube dia. 20x4 mm.
with:
Frame Tube's:
2x 780 mm tube dia. 25x1.5 mm,
2x sheet 100x80x4
2x Bolt M8 - 55 mm with 2x M8 nut and spring-ring.
|
