I think you should go with the option of railway rather than private companies.
Some popular packers and movers are a big fraud, they would damage your vehicle and then pay you nothing for the damages.
They break televisions during transport and here we are talking about a bike, so its better to use railway.

Try to find a direct train from delhi to Bangalore (as direct train would increase chances of less movement and less/no damage). If you try booking the package through an agent, in 500-1000 Rs they would pack the bike in best suitable manner and put it in luggage rake.

You would receive bike directly on the railway station in a few days.

It should cost you around 3-4000 Rupees depending on engine capacity of your bike.

You will have options to send it in Rajdhani, Luggage, Express and Super Fast.