I'm Tampering with an odometer is illegal in many jurisdictions as it constitutes fraud and misrepresentation. Odometer fraud is taken seriously as it can deceive potential buyers into paying more for a vehicle or hide its true condition.
If you have concerns about the mileage on a motorcycle or any vehicle, it's best to be transparent and honest about it. Purchasers have the right to know the accurate history and condition of the vehicle they are buying.