motorcycle inner tube size as follows, Sizes Tyres net weight(kg) Tubes net weight(kg) 2.75-18/6PR 2.5 0.39 3.00-18/6PR 2.9 0.46 3.25-16/6PR 2.9 0.46 2.75-16/6PR 2.0 0.36 100/90-18/6PR 3.7 0.54 100/90-19/6PR 5.2 0.8 3.00-17/6PR 2.8 0.43 3.50-10/6PR 1.9 0.32 90/100-10/6PR 1.7 0.30