octane booster

[Ben Hur]

Guys,

Our fuel here is the same as the regular unleaded in the UK (95 RON, depending on the quality of the petrol station you use)...is there any justification to running an octane booster - I am not after performance increases, but more interested in protecting the engine since I read that octane boosters can protect valves and valve seats...

Thanks

R.

 

[hotbulb]

As far as I'm aware,any protective effects from octane boosters will only benefit engines having unhardened valve seats (and presumably valves)...old engines designed for (high) leaded petrols. My elderly Land Rover falls into this category, but runs quite happily on unleaded petrol, it doesn't need the raised octane rating - it would run happily on paraffin, I'm sure - and it's a low output,low-revving engine, which doesn't stress the valve seats etc. All modern bikes will be suitable for unleaded petrol,with hardened valve seats etc,and do not need the extra protection. It's only IF your engine can benefit from a higheroctane fuel that the extra cost of the booster will be justified. I believe all "adventure" type bikes are set-up to run on standard unleaded (lowish-octane) petrol ... only a very few have ignition adjustment available to take advantage of a higher octane fuel ( to run more spark advance) to produce a little more power.
I hasten to add... these are only my thoughts/opinions - others may have more information to impart
(too much time on my hands - hence the wordy reply !)
:wales-emoticon-vlag:

 

[nigelphoto]

Guys,

Our fuel here is the same as the regular unleaded in the UK (95 RON, depending on the quality of the petrol station you use)...is there any justification to running an octane booster - I am not after performance increases, but more interested in protecting the engine since I read that octane boosters can protect valves and valve seats...

Thanks

R.

You don't say where 'here' is, or what bike(s) you ride but regular unleaded is 91RON and super unleaded is 95RON. Any engine built after 1986 (when unleaded was introduced in the UK) and a lot before, will have austenetic steel valves and run on 91RON. As an engine wears (100,000 miles) or if the CR is over 11.5 to 1 it can be an advantage to run 95RON if there is any tendency to pink (pre-ignition), but in the normal course of events you will be doing your engine a great favour to stick to 91RON or regular unleaded if you live in the US or the EC and never, ever put any silly additives in the tank. You will also save enough money each week to buy a case of Brown Ale and chill out and not worry about your engine!

 

[Rubberchicken]

but in the normal course of events you will be doing your engine a great favour to stick to 91RON

Why?

I get the cost aspect, but my engine doesn't care about cost. (Oh indeed... ) So why would you be doing your engine a favour?

 

[Ben Hur]

@nigelphoto....

Sorry here is Malta and our fuel is or should be Ron95. I thought this was normal unleaded in Europe. I ride a transalpbxl650v (csrburretor engine) and an fjr1300(fi engine)

Sent from my GT-I9505 using Tapatalk

 

[nigelphoto]

but in the normal course of events you will be doing your engine a great favour to stick to 91RON

Why?

I get the cost aspect, but my engine doesn't care about cost. (Oh indeed... ) So why would you be doing your engine a favour?

Err, because as likely as not its whats specified in the handbook. The manufacturer spends hundreds of thousands on R&D and there are an unquantifiable amount of variables throughout the rev range and under a miriad of different conditions which effect combustion, all of which are controlled by the ECU and various sensors around the engine. The characteristics of petrol are that 95RON ignites at a higher temp (which comes as a result of higher compression in a tuned engine) but burn time, brake mean effective pressure, economy, mechanical longevity and everything else will be the same as 91RON, whatever else the fuel company marketing spiel might say. So if your engine is designed for 95RON you will damage it by trying to cut costs and run on 91RON unless you retard the ignition or compensate by accelerating very slowly especially going up hill. However, the same is not true the other way round; if your engine is designed to run 91RON then spending the extra on 95RON achieves nothing except for the satisfaction of spending more money. Although it will not cause any deleterious effects, there is no gain either and it certainly won't magically increase the longevity of any internal components. Contrary to popular misconception unleaded petrol requires special grade steel valves, but not hardened valve seats unless its an old iron head. Running 95RON in an engine requiring 91RON isn't going to do anything positive or negative to the valves/guides/seats: running 91RON in a high CR engine will cause pinking which will burn the tips of the spark plugs, very quickly damage the crank bearings etc. Before ECU's/cats/fuel injection (ah, the good ole days) one could do a plug chop and see exactly how an engine was burning the fuel, but regrettably thats all in the past (except for us silly old booggers who still ride BMWs with carbs!) so it is best to stick closely to the manufacturer's specifications for oil/fuel/plugs etc as that will give the ideal working conditions and compromise between emissions, fuel economy, performance, mechanical longevity etc.

PS Sorry this is so long and boring, yawn, yawn

 

[hotbulb]

Contrary to popular misconception unleaded petrol requires special grade steel valves, but not hardened valve seats unless its an old iron head. Running 95RON in an engine requiring 91RON isn't going to do anything positive or negative to the valves/guides/seats: running 91RON in a high CR engine will cause pinking which will burn the tips of the spark plugs, very quickly damage the crank bearings etc.

I suspect my Land Rover's head is made of granite, or limestone... it's that old! No, it's cast iron, really. My mileage these days is very low, and I've not had the head off in years. But I do keep an eye on "tappet" clearances, and there's no valve seat recession as yet, in spite of many years running on unleaded Initially I did use a "lead replacement" additive,but very sooon decided it wasn't worth the extra expense. And for the same reason i didn't have the head bored out to take hardened seat inserts.
-----
Back to bikes: I seem to recall reading somewhere that some bikes (I suspect BMW, but I may be wrong) have a wiring socket into which some gizmo can be inserted to change the ignition advance for users of high-octane (but still unleaded) petrol.....and don't get me started on catalytic convertors!

:marin-simpson:

 

[Boris]

Back to bikes: I seem to recall reading somewhere that some bikes (I suspect BMW, but I may be wrong) have a wiring socket into which some gizmo can be inserted to change the ignition advance for users of high-octane (but still unleaded) petrol.....and don't get me started on catalytic convertors!

:marin-simpson:

I did have a car (can't remember which) that had such a plug. As for the beemer my 1200 automatically adjusts between say 91 and 98 but if you were planning to go further afield there is a software update that enables it down to a much lower number.

(I cant remember the exact number but I'm sure you get the gist)

 

[Rubberchicken]

PS Sorry this is so long and boring, yawn, yawn

That was a bit of a long winded way to say running on 95 instead of 91 doesn't make a blind bit of difference for the engine, yeah.

I run on 98 whenever I can get it though, which is most of the time. Bit more expensive, but in the past it actually did run better under load on the higher octane stuff. Probably doesn't matter anymore since I twinsparked it, but habits, etc. (Who knows, I might at one point stick Moorespeed high compression pistons in. Hello +10bhp. ) And I haven't got knock sensors or computers adjusting ignition timing or anything, just a pair of carbs from a bygone era where there weren't people spoiling perfectly good petrol by putting ethanol or similar rubbish in. I'm not entirely sure that stuff is harmless for various 20+ year old components, including that big-arsed plastic petrol tank.

 

[jasonbc]

I just stumbled upon this thread, i don't normally use additives in the bike but for the car i normally stick with Forte or Wurth products. However due to the bike not being used much last year as the baby was only 1 when i took it out this week my reserve light came on and locally all i have is supermarkets with s*it quality fuel. When i got home i went to the bike shop across the road and bought one of the Putoline additives just to try

http://www.putoline.com/en/products/cat ... e-cleaner/

They do 4 different ones in the fuel range i chose this one, then i rode to a local shell a few miles away and put £20 worth of Vmax or optomax or whatever it's called now in the bike. In the past putting these more expensive fuels in have never made any difference to fuel economy or throttle response but i thought id treat the old girl.
I haven't done enough miles on it yet to see any difference but if i do notice any i will report back. As for octane boosters years ago i tried the Silkolene proboost in my firestorm and it did make a little difference but i think the the main reason they sell this one was it used to reduce carb icing on someof the bike that suffered from that. I'm not going to use any of that stuff in the Varadero as it's not required

 

[nigelphoto]

This might help to clarify who sells what from the big petrol companies here in the UK -

Outlet Product Octane
BP Unleaded 91
Premium Unleaded 95
Ultimate Unleaded 98
Mobil Unleaded 91
Premium Unleaded 95
Premium Unleaded 98
Shell Unleaded 91
Unleaded 95
V-Power 98

Morrisons have curiously removed the BS kite mark from their petrol pumps and are very coy about what they are actually selling. When asked, all they will admit to is that it meets 'E10' specifications which means its made up of 10% bioethanol which could be distilled elephant grass, maize or even cow plops! Please note that unless your handbook (or handbuch for us German/Austrian owners) states specifically that your engine can run a 10% bioethanol mix then DON'T. I say Morrisons, but that obviously includes all Supermarkets, its just that Morrisons are local to me.

As an interesting aside, my 1997 F650ST handbuch gives the compression ratio as 9.7:1 which is not particularly high and should run 91 but recommends 95RON. About 2 years into production (i.e. from a certain chassis no.) they reduced it to 91RON although there were no changes to the engine whatsoever. On the F650 Forum it seems most people stick to 95RON.

 

[Rubberchicken]

the compression ratio as 9.7:1 which is not particularly high

Not particularly low either, the high comp pistons I've been eyeballing lately still come in lower than that.

My GS came with a rather humdrum 8.5:1 from the factory, and that would still give the occasional ping on 95 when you put extreme loads on it. Carburettors again, I suppose... We don't even have 91 where I live, so that's not an issue at least.

(Just checked. 12GSA is 11:1. Jeeze. No wonder there's so much power in those things. Nice BMW specs pages: http://www.bmbikes.co.uk/bmwmodels.htm)

 

[jasonbc]

This might help to clarify who sells what from the big petrol companies here in the UK -

Outlet Product Octane
BP Unleaded 91
Premium Unleaded 95
Ultimate Unleaded 98
Mobil Unleaded 91
Premium Unleaded 95
Premium Unleaded 98
Shell Unleaded 91
Unleaded 95
V-Power 98

Those figures i themselves don't actually mean very much, Tesco's high octane is either 98 or 99ron but the petrol is still poor quality and doesn't have the extra chemicals and detergents in it that the likes of Shell, BP and Texaco do.

I'm in the same boat as you the main fuel stations to me are supermarkets and i had been using Morrisons which i have now stopped using in the last few weeks. Nearest Shell or Texaco to me about 2 1/2 miles so i will be using them now. My truck does seem to run better on there fuels it became very sluggish on the Morrison's fuel.The other one that has sprung up down here since JET pulled out of Cornwall is Harvest and they are the same as supermarket fuels as they are only a fuel broker so you will never get high quality fuel from them

 

[nigelphoto]

This might help to clarify who sells what from the big petrol companies here in the UK -

Outlet Product Octane
BP Unleaded 91
Premium Unleaded 95
Ultimate Unleaded 98
Mobil Unleaded 91
Premium Unleaded 95
Premium Unleaded 98
Shell Unleaded 91
Unleaded 95
V-Power 98

Those figures i themselves don't actually mean very much,

Sorry, I should have made it clearer that I put this table up to point out how difficult it is when you draw up to the pumps to actually identify which nozzle you need, as all the fuel companies use different names. I have also contacted a mate who is a qualified engineer and who incidentally rides a very nice 1992 R100 amongst others, and his comments were 'I often seek out the higher octane or premium fuel for my old bikes, not because they need it (they dont) but because research suggests that at present the oil companies only infect the bulk sale lower grades of fuel with Ethanol and the premium fuels are currently free of the ghastly stuff.......which means quite a lot as you don't want Ethanol anywhere near your fuel system if it can be avoided'.

He also went on to explain that on combustion with higher grades (95-99) the flame path is more even across the top of the piston so it would in fact give a smoother power stroke and theoretically slightly better mpg, but not more power. So I suppose I should modify my OP to say even if your bike handbook specifies 91RON, avoid it and put in 95 or higher so you don't contaminate your engine with bioethanol.

PS This is twice in two days I have been wrong, the last one was my post in the thread about ear plugs. Damn it!

 

[Rubberchicken]

I have also contacted a mate who is a qualified engineer and who incidentally rides a very nice 1992 R100 amongst others, and his comments were 'I often seek out the higher octane or premium fuel for my old bikes, not because they need it (they dont) but because research suggests that at present the oil companies only infect the bulk sale lower grades of fuel with Ethanol and the premium fuels are currently free of the ghastly stuff.......which means quite a lot as you don't want Ethanol anywhere near your fuel system if it can be avoided'.

Wot he said!
(Said the other one with the nice 1992 R100)

PS This is twice in two days I have been wrong, the last one was my post in the thread about ear plugs. Damn it!

Hey, at least you can admit it.

 

[nigelphoto]

As a Postscript to this discussion I thought I'd mention that today I have had to strip and clean out the petrol tap on my F650. The last time out I noticed my left boot smelt strongly of petrol and I saw an occasional drip from the tap in the 'on' position but not 'off' or 'res'. I got a gasket set from Motorworks at £7 inc P&P, emptied the tank and took the cover off the tap. The inside of the base-metal tap was badly corroded which is a sure sign of ethanol in 91RON fuel, and I had to gently scrape the gasket housing with a small screwdriver and sand it clean to get the gasket to sit evenly. I put it back together with a very fine coating of black silicon gasket seal and this seems to have done the trick - no more drips. Its probably been filled over all of its 17 year existence with 91RON but its strictly Super Unleaded from here on in.