There are two methods of getting your pre-2007 Monster exempted from ULEZ charges in London, an emissions test or submitting documentation to TFL. The test method currently costs £175 including VAT (assuming your bike meets the standard without further tuning), The documentation method should be free. The method you choose depends on how much time you have and what you want to spend.
Most standard Monsters should meet or be close to meeting the standard, high flow air filters and race pipes etc. may make this a bit harder.
The current standard is less than 0.15g/km of NOx (Nitrogen Oxides) in the exhaust gasses, eg. Euro3 for motorcycles.
Some example figures are:
Year | Model | NOx | Source | |
| | | | |
1997 | 900SS | 0.14 | Test | (similar engine to M900) |
1998 | 916 | 0.09 | Test | (similar engine to S4) |
2000 | M600 | 0.11 | Documentation | | |
2003 | M1000S | 0.132 | Documentation | | |
2006 | S2R1000 | 0.036 | Documentation | (Euro3 but not post 2007, TFL want further docs) |