The average Joe can be seen filling up his 100 cc commuter bike with a hundred rupees’ worth of petrol — but most experts recommend you tank up. What is right? What is the right kind of fuel for your vehicle?
Let’s start with the basics — petrol, diesel, kerosene, even aircraft turbine fuel and the tar we use for our roads, come from crude oil sucked up from inside the earth’s crust. They are separated from one another in refineries, and then refined to the required extent to remove impurities. Formula One teams use synthetic fuels (as they do oils) since that eliminates the possibility of impurities — no matter how good the refining process, a miniscule amount of impurities will remain.
Know the efficiency
The reason experts tell you to tank up whenever you go to a petrol pump is so you get to know what the real fuel efficiency of your car or bike is. If you’ve got a tripmeter, it might be a good idea to reset it every time you tank up, so you can calculate the ‘average’ immediately. A very low reading will suggest that all is not well with your vehicle. Run your vehicle for at least 60-100 km for a proper reading. You can also further eliminate error by tanking up at the same pump; even the same nozzle, if possible. Do not brim petrol cars right to the top, it isn’t good for them.
The fuels we use have particular ‘octane ratings’ which, simply put, denote the resistance the fuel has to detonating by itself. Petrol has ‘octane’ ratings, while diesel has ‘cetane’ numbers. The higher the octane rating of petrol, the more its resistance to detonate on it own, without a spark. On the other hand, the higher the cetane number of diesel, the quicker it will ignite when compressed. Let’s deal with octane ratings in further detail, since diesel with a higher cetane rating than usual is extremely rare in our country.
Know your petrol
The regular petrol you buy at the pump is rated 87 RON (Research Octane Number), and all vehicles sold in our country will run on this fuel. You may argue that certain high-performance vehicles need higher octane fuel, and you’d be right. However, cars like the Audi A4 3.2 FSI recommend 95 RON fuel for optimum performance — but that doesn’t mean they won’t work on regular fuel. However, there will be a dip in performance and fuel efficiency.
Branded fuels like BP’s Speed or HP’s Power are regular fuel with additives. These additives help clear things like carbon deposits that form when unburnt fuel is left in the engine, and your injectors that will eventually get clogged with the kind of fuel quality we have. It is a good idea to tank up once in a while on these fuels to clean out the system, but a better idea would be to add an aftermarket additive to the fuel yourself. The same applies to octane boosters — if you own an A4 3.2 or any other high-performance car, keep a bottle of octane booster handy. This also applies to owners of cars like the Octavia petrol and the second-generation Honda City, whose engines run a high compression ratio.
At approximately Rs 70 per litre, 97 RON petrol isn’t exactly cheap, and the only place you’ll manage to get your hands on some will be at the heart of a city. A 350 ml bottle of octane booster will generally suffice for a full tank. Do not go overboard with the booster, as it may cause damage to your engine, and those repairs will be expensive — this applies doubly to a motorcycle owner. Our bikes aren’t made to withstand the stress that our cars can handle, so add the booster in incremental steps.
Higher octane fuels work better with carburettors since modern fuel injection systems can cope with pretty much anything. Take special care to keep water out of your fuel tank this monsoon, and ride/drive carefully on wet roads.