2-Stroke Engine Compatibility ✅
Yes! The Duluth Cycle Advanced Chain Tensioner is specifically designed for 2-stroke motorized bicycle engines:
- 49cc 2-stroke ✅
- 66cc 2-stroke ✅
- 80cc 2-stroke ✅
Our tensioner is engineered for the standard #415 chain used by virtually all 2-stroke motorized bicycle engine kits.
4-Stroke Engine Compatibility ⚠️
It depends on your setup.
4-Stroke Engines Using #415 Chain
If your 4-stroke engine kit uses the standard #415 chain (same as 2-stroke kits), our tensioner will work. Many 49cc and 79cc 4-stroke kits use this chain size.
4-Stroke Engines Using Different Chains
Some 4-stroke kits—particularly larger displacement engines like 79cc, 99cc, or 212cc—may use heavier-duty chains (#420, #41, etc.). Our tensioner is optimized for #415 chain and may not be ideal for these larger chain sizes.
How to Check Your Chain Size
Look for markings stamped on your chain links. Common motorized bicycle chain sizes:
| Chain Type | Typical Use |
|---|---|
| #415 | Most 2-stroke kits, some small 4-stroke kits |
| #420 | Larger 4-stroke engines, mini bikes |
| #41 | Heavy-duty applications |
Jan 13, 2026