[Bike Mod] 650/250/125 – AiS Block Off Removal (EGR Delete)
⚠ WARNING: This guide involves AIS (EGR) removal. Follow at your own risk! Incorrect modifications can damage your bike or void warranties. Make sure you understand the steps fully before attempting.
Credits: I did not write this, but full credit to the lad who created this book. (BTW, follow at your own risk!)
Benefits & Proofs
Aimed at 650cc bikes but the same method also applies to smaller CC bikes.
Deleting the AIS (EGR block) from the bike results in:
- Loud pops on the exhaust pipes
- Deeper groans on idle (louder induction roar)
- Improved performance from 4-7k rpm, especially for low CC bikes
- Recommended for stainless pipes anyway
- First step race teams take—removing parasitic parts
- Overall marginally louder bike
What is AIS? (Often incorrectly called EGR by uneducated mechanics)
- It makes the bike “fake” its emissions by burning cleaner air to meet Euro laws.
That’s it!
- It has never proven to benefit bikes; it actually “steals” energy from the engine. Think of it like a “Remora” fish under a shark, migrating across the seas 😉