Welding of the brake pedal and footrest is finished. The footrest was extended 1.5 inches either side and the brake pedal was shaved on the left side and added about an inch to the right. Continue reading Honda Cub 70cc to 100cc conversion Day 5
Category: black cub
Honda Cub 70cc to 100cc conversion Day 4
Home stretch! Only need to work on the exhaust and do some machine shop work to parts that need to be cut or widened to accommodate the larger engine.
I plan to have the brake pedal cut and added so it won’t hit the crankcase.

Honda Cub 70cc to 100cc conversion Day 3
Wave 100 internals to EX3 engine conversion aka ‘Project WavEX3’, Day 3. First start! Some problems:
Honda Cub 70cc to 100cc conversion Day 2
- Good news the neutral indicator was just a straight swap from the ex3 to wave 100 gear shift.
EX3 neutral indicator is straight swap to wave 100 gear shift - Here are pics of the 4 speed wave and 3 speed c70 transmission assemblies for comparison. Nearly same sizes for each.
Transmission assembly comparison - The bearings proved difficult to find. I needed ‘open seal’ bearings so it took two trips to buy and return them then find another. A nice old man at BRITE TOWN auto parts along Sucat helped by showing you can remove the seals and they’ll be ok. Thanks so much to the nice old man!
- Machine shop work: The smallest #6200 bearing was removed, the cylinder stud hole was re thread and the crankshaft thread was rethread. Cost P700.
- The bearings issue took so long it got late and I had to go home. Will come back Wednesday.
Honda Cub 70cc to 100cc conversion
I finally bought a Honda Wave 100 engine for my Honda C70 EX3. Here it is.
Of course I wanted a 110cc or maybe even a 125 but I settled on a 100 because it’s just really hard to find one for sale that’s either still intact and nearby. I had been waiting almost a year and drove 80km to Laguna (back and forth) to pick this one up. Most are sold in smaller pieces so the seller can make more money. Continue reading Honda Cub 70cc to 100cc conversion