Reply To: Scrambler Gearing. Great British Handcrafted Motorcycles › Forums › Spitfire – Scrambler › Scrambler Gearing. › Reply To: Scrambler Gearing. 14 July, 2020 at 9:45 pm #5538 Scrambler126Member Mine will do over 90 mph on stock tyres and then its getting a bit vague in the steering. You can get a smaller rear sprocket I expect, but it will run at 70-80 on the motorway which is good enough for me.