Fuel - 95 vs 97.

[garynortheast]

Bike is a SV650sy (2000 curvy). Normally runs on 95 ron but now and then I'll run a tankful of 97 ron through. I filled up with 97 a few days ago and remembered just what a huge difference it makes to the engine feel and characteristics. It's a 75,000 mile engine and runs quite nicely on 95 ron but the 97 has it running so much more smoothly. It's not an imagined difference either. It pulls much more cleanly from much lower rpm, ticks over much more steadily, especially from cold, it has a much crisper note from the silencer. I shall be interested to see if the mpg is improved too, although that may be asking a lot from a bike that already gives around 60mpg.

I'm due to fill up again soon so I'll put some more 95 back in the tank and see what happens over the next 200 miles/tankful of fuel.

[Craig380]

When I got my K6 I ran it on Shell V-Power for a few tanks, largely because it had only done 7,500 miles in 9 years when I bought it, so my main aim was that the V-Power might help clean up any crud / deposits on the injectors (one of the big claims is better detergent additives).

I usually just fill up with regular 95RON now, and can't tell any difference. Although I would expect the later injected bikes would be more tolerant of different fuels because of the pressure at the injectors and the closer control over fuelling.

[Blapper]

I did try the good stuff once and there was a small performance improvement as you said, but I didn't notice an improvement in fuel economy on my curvy.

[Craig380]

Also, even with bog standard 95, we're better off than our US-based counterparts, their standard stuff is 91 and the best they can get is 93

The SV is designed to take crap fuel, but good fuel won't do any harm at all.

[Bibio]

only if the fuel can be burnt efficiently in the first place. a badly running bike will still be a badly running bike even with the higher ron.

[Mark_h]

Mine needed 97 in the winter as otherwise it struggled to start.

[tom_e]

I use V power simply because it costs so little extra when you're talking about brimming a bike tank that even if it only keeps the engine running a little cleaner and easier then it's worth it. Also because Shell is on my way home from work, any other stations require detours.

[ophic]

It's probably got more to do with the extras in the premium 97 RON fuel than the standard cheap 95 stuff, rather than the RON rating itself.

The 95 probably has more ethanol and fewer detergents.

In terms of RON, I think the SV is designed to handle 85. Anything above that is fine but shouldn't make any difference to running.

[garynortheast]

I'd hazard a guess that you're right about that Ophic. It could well be the general cleaning effect of the higher rated fuel. I've just filled the tank again at 195 miles (fuel light started flashing at 187 miles) and ridden the 7.5 miles home from the garage. The engine still feels very smooth, still punchy from low rpm, and still ticking over very cleanly. We'll see how it is after a couple of tanks of the 95.

[Craig380]

Originally Posted by garynortheast

I've just filled the tank again at 195 miles (fuel light started flashing at 187 miles)

How much fuel did you squeeze in, out of interest? When my fuel light starts flashing (K6), I can usually only get about 10 litres in before the pump starts cutting out all the time, and the fuel level is right up to the filler neck. That's about 130 - 140 miles.