It has been revealed by the Environmental Transport Association (ETA) that recent changes to the law have meant that cars which emit less that 100g of CO2 per kilometre travelled will be exempt from paying Road Tax or Vehicle Excise Duty, despite this, motorcycles are still expected to pay.

The Chancellor, Alistair Darling, revealed his plans in the recent budget, he said he was going to reward motorists for driving green vehicles.

Despite Darling's aim and promises, the road tax paid by motorcyclists is going to double in 2009 according to the ETA. The annual charge for a typical 125cc commuter bike is set to grow from the present £15 per month to £33 per month in 2009.

The director of ETA, Andrew Davis, says that the increase "makes a nonsense of the revised rates of vehicle excise duty, and that a case must be made for motorcycles." Motorcycles tend to emit less CO2 and use less fuel than cars, so if green cars are not going to have to pay road tax, why are bikes still liable?

This criticism from the ETA is damning, it is a non-profit organisation that campaigns for sustainable transport, and also provides carbon-neutral breakdown cover. According to the organisation the average CO2 output for motorcycles is 110g/km.

With the cost of road tax set to rise for bikers it is important that other costs are kept down, there are a number of ways to keep the cost of bike insurance to a minimum. The first being to compare the small print of different policies, the cheapest policy is not always the best, terms and conditions on driving abroad and excesses you are liable for will differ from one insurer to another. This is always worth checking.

Some policies will include cover for riding other motorcycles than your own for third party damage. This extension of your own cover is only valid if the bike is insured by its owner. Also once you park the bike it is not insured until the owner re-takes possession of the bike.

Modifications to your bike are not always a bad thing. With cars modifications often increase the price of your car insurance premium, obviously If you modify your bike in a way which enhances the performance a lot you can expect higher premiums, you must make sure you declare any modifications fully to your insurer. If you do not disclose any modifications any claims you make could be rejected and your policy could be void.

Some policies include cover for any legal expenses you may incur, this can be useful but it if often included free in policies, this is a point you will be able to easily negotiate with your insurer to save a few pounds on the price of your policy.

Many people try to save money on their bike insurance by increasing the amount of excess they are willing to pay in the event of a claim, as the premium price will be lowered. However it is also worth decreasing your voluntary excess, sometimes it is possible to get the same price for a lower excess.

Paying your insurance premium off in a lump sum will also save you money, paying monthly by direct debit sometimes racks up as much as 30% interest, if you can't pay for the whole policy up front use a 0% purchase credit card and pay off the balance in full before your term ends on that.

When it comes to renewing your insurance policy shop around, insurers do not reward your loyalty and you can often find a better price with a different insurer.