Octane Boosters? Do they work?

Question

Are these products any good? If yes, which ones work the best. I have a medium high compression (10.5 to 1) and my bike pings even on 91oct premium. There is a station in my area that sells 100 oct racing gas and that solves my problem but at $7.60 a gallon ( ! ) I don't want to make a steady diet of that stuff. Any suggestions?

Answer 1

Sounds to me like you have either a carburetor problem or the ignition timing is off.

Your fuel / air mixture is too lean

or

Your ignition timing is too advanced.

You may also have the incorrect spark plug for your application.  Try a colder spark plug.

The bike with this compression ratio should run on 91 octane without any problems.

Answer 2

you can also try to mix the fuels. take 10 gallons of 100 and 10 gallons of 91. when mixed the octane will settle at around 95-96. its just a way to save a little money. i tried octane boosters i my car and it wore my rings, burned my pistons and destroyed my gaskets. granted i used it alot (about 20 times) and the power increase was great but it destroyed my car. some people swear by it though.

Answer 3

The difference between unleaded petrol and super unleaded petrol at the pump is how much "aromatic hydrocarbons they put in" - in English, this usually means xylene, toluene, benzene and sometimes a few others odds and ends.

The old "Rocket fuel" they used to use was 84% toluene and 16% n-heptane - which REDUCED the octane rating to comply with the requirements of the race - max value of 102

In short, toluene is a SUPERB octane booster and if you have an engine that has high compression / high boost / advanced timing, then toluene is a superbly cost-efficient octane booster - which os both o2 sensor and cat friendly.

It is also gloriously cheap - compared to the pretty little bottles of booster you can buy 125ml at a time.

I just buy 25 litre drums of the stuff. It has an R+M/2 rating of 114 - so just one gallon in ten can raise octane very nicely - AND cheaply.

All that aside, I do tend to agree with the other folks who are saying it sounds as though something has happened to your bike, has someone worked on the engine before - a very heavy skim can increase compression a lot more than some folks give credit for.

Assuming you are happy wit the way your bike is and feel the mixture / timing etc is already spot-on, then I would try some fuel from other garages in the area - does the 91 station perhaps have old fuel?

with toluene, you can also start with a known amount of fuel in the tank - eg: 5 litres, then try adding 500ml of toluene (10% mix). Does this solve the problem? If so, next time, try just 250ml. If it DOESN'T stop it knocking, then perhaps add another 250ml - 15% mix.

If anyone tells you toluene is a paint stripper - yada yada yada - well it IS - but it happens to also be the MAIN ingredient the fuel companies use to raise octane - the fact that it has a "base" use doesn't mean it is bad to use in your fuel tank :)

You can also use xylene - but that is an aggressive solvent (even dissolves sulphur) - and it is rare for fuel companies to add more than a few percent at most.

Answer 4

It would help if you told us year, make, model, and any other mods to the bike.  Some cylinder head designs will ping with 10.5:1 cr, where others designs can run 12.5:1 with the same fuel.  If the bike is running a bit lean, this will cause pinging, if compression is high, piston is carbon coated, spark plug too hot - on and on. Retarding the ignition advance will help.  Some of the octane boosters are good, but do not use over the recommended mix.  

As an example, I have a 1109cc ZX11, 12.5:1 cr, good cam set, 4>1 exhaust, dual ram air. Standard advance, use 93 octane.  Never have had detonation, will red line in 6th gear.  Also have a English version 1986 "Racer Replica". which was a 1100cc version of the Lawson Replica which was sold here.   This bike now has a 1260 kit, cams, 4>1 pipe, etc. Compression is 10.5:1. Does not run good with retarded timing, but a dose of octane booster, and it flies.

So, you are not alone with your problem, if I knew more about the bike, could be a bit more help, but it can be cured.  If you like, you may E-mail me, and give more details, I most likely can help.

Tomcotexas.

[e-mail]  

Answer 5

I'd try the mix. Most bikes have a 4 gallon tank. Try one gallon of 100 and 3 gallons of 93. I know you mentioned 91 but if they have 100 they should have 93.

The octane boosters aren't very popular in bikes for various reasons. Just use better gas.

I don't know of any mechanical tweaks you could make to remedy the situation but maybe you should have a mechanic check things out.

Answer 6

Octane boosters are just fine... we use STP and various others since the only station selling 100 around here quit. We start all our new motors for bench warm up with a capfull or two and sell small bottles of it to all our customers who ride out west and may not even find 91. The other rub for hi perf engines as well as stock air cooled is the ethanol additive mandated by the idiots on capital hill. While they have some info to say your car is ok with it they have NO info on how it will effect m/c engines. One thing we do know... while Eth ups octane rating, it burns hotter.