Britbike forum

Fuel Additives

Posted By: Blapper

Fuel Additives - 01/02/08 10:26 pm

Hi all,

If I understand points made in other postings recently, it seems that one of the biggest risks to a motor in the first couple of hundred miles or so after rebuild is damage done by oil passing the rings and lowering the octane rating of the fuel causing a partial or complete seizure.

What are the views on using fuel additives to reduce the risk during this time? It makes sense to me, what say you?

Blapper redwine
Posted By: JubeePrince

Re: Fuel Additives - 01/02/08 11:28 pm

I have no idea what the benefits/risks would be of a fuel additive to break in an engine......

I would think that if the barrels, pistons, rings and valves have been prepped correctly, a nice spirited run at start-up should bed the rings and prevent the condition you describe?

Perhaps retarding the ignition a degree or two?

Cheers,

Steve
Posted By: HawaiianTiger

Re: Fuel Additives - 01/03/08 12:39 am

50's Triumphs came from the factory with the needle on one notch to the rich. At the 500 mi. service they would return it to the normal position. Not only does the octane rating drop with oil present but the mixture weakens when part of the incoming charge escapes past the rings. Not a happy situation for proper combustion.
Bill
Posted By: Blapper

Re: Fuel Additives - 01/03/08 10:03 am

Steve,
Risks should be none, benefit are that the situation JH describes so graphically can be prevented.
Bill,
Worth a thought.

Thanks, Blapper redwine
Posted By: Britbodger R.I.P.

Re: Fuel Additives - 01/03/08 12:58 pm

Just as a more extreme example of breaking-in an engine:

On a fresh rebore and new pistons and rings started for the first time and broke-in my T120 with Routt barrel and MAP billet pistons during practice sessions at a road race meeting last year. At the end of the practice sessions (about 25 miles) had the throttle wide open and, of course, in my races as well.

Should mention that the bore was expertly honed with torque plate to the correct finish (by Marino's brother Terry) for ductile steel rings with 5.1/2 thou piston to wall clearance.

A subsequent strip-down revealed the bore and pistons and rings to be in good condition with evidence of good ring seating. Pistons did have slight scuff marks.

Course may have shortened the life of the cylinder, pistons and rings using this procedure but just trying to illustrate that high rpm doesn't necessarily result in seizure - admittedly with genorous piston to bore clearance.

beerchug

P.S. Also should mention that I took the precaution of using Aviation Shell 100 (50w) for the break-in as it was very hot at that particular track at Albuquerue New Mexico
Posted By: Peter Jones

Re: Fuel Additives - 01/03/08 3:16 pm

I've heard of 2-stroke racers using even more extreme methods, rinning it hard 'til it siezes then polishing the scuffs off the piston eek
Posted By: gs750

Re: Fuel Additives - 01/03/08 3:29 pm

The only seizure I've ever experienced on a newly rebuilt motor was knocking along at about 55mph at medium revs.

Since then, and after reading 'millions' of posts on the subject, I adopted the Britbodger 'ride it like you stole it' approach and have not had another problem.

John Healy's 'dry assembly' is also part of my routine now.
Posted By: John Healy

Re: Fuel Additives - 01/03/08 5:14 pm

"John Healy's 'dry assembly' is also part of my routine now."

I can't claim this as it was told to me in 1978 by Ken Tipton of MTC Engineering.

http://www.mtceng.com/images/pdf_files/piston_kit_installation.pdf
Posted By: Blapper

Re: Fuel Additives - 01/03/08 7:46 pm

Does anybody have any views on, or actual experience of, fuel additives? Has anybody had any (temporary as in caused by oil as per JH's scenario) detonation problems (temporarily) cured by it?

Blapper redwine
Posted By: btour

Re: Fuel Additives - 01/03/08 8:12 pm

Hi Blapper,

You keep asking this question. You are probably not going to get many answers, about fuel additives, for octane. Do a search. There have been mentions of them. Consensus is they do not work and may cause harm.

Why don't you search and find, Real gas. There must be a race track somewhere near you. Or a small airport for AV gas.

Problem is not just octane. Problem is alcohol, which burns slower. Thus causing a "premature end end to combustion" = detonation.

Thus AV gas. Race = real gas (no nitro). Or second spark plug, stronger EI ignition.

I doubt, you will find, just adding a can of this or that will work.
Posted By: Britbodger R.I.P.

Re: Fuel Additives - 01/03/08 8:48 pm

With all due respect Bob, alcohol (both ethanol and methanol) possesses very good anti-knock properties. Unfortunately it doesn't possess as much unit energy as gasoline so for the same carburation/jet size and C.R., power output is less for a alcohol/gas mixture than for straight gasoline.

Its academic for Blapper though as I don't think they use alcohol in Europe - yet.

I do agree that mixing-in a small amount of 110 octane leaded race fuel or aviation 100LL (actually about 108 octane using (MOM+RON)2 octane rating method)fuel might be helpfull if Blapper can get hold of some.

Personally though I don't think it is of real concern using pump gasoline as the rings should seat in much less than 200 miles and the oil bypass before then should be so small in my opinion as not to cause a problem .

BTW I think aviation is slow burning which isn't a bad thing in my opinion unless looking for out and out performance.

My 2c

Still haven't answered Blapper's question re-octane boosting additives as don't know sufficient about the subject other than what I've gleaned from others
Posted By: Blapper

Re: Fuel Additives - 01/03/08 8:57 pm

Thanks guys, at least I've got a response to the original question now.

I do have a small airfield near hear, I'll go and see if I can buy some gas from them nearer the time I need it. From what you say, a couple of gallons should do it. Good idea chaps.

Thanks :bigt:

Blapper redwine
Posted By: btour

Re: Fuel Additives - 01/03/08 9:24 pm

Hi Blapper,

Here in the States we have to tell them it is for "off road" use.

There are different colors of AV gas. I think I remember some are good for us others bad. Do a search, it was covered here.
Posted By: Britbodger R.I.P.

Re: Fuel Additives - 01/03/08 9:36 pm

Blapper,

100LL is good - contains more tetraethyl (spelling?) lead than the old auto leaded gasolines and is about 108 octane based upon (MON+RON)/2 formula so you don't need much.

HTH
Posted By: John Healy

Re: Fuel Additives - 01/04/08 12:24 am

"Personally though I don't think it is of real concern using pump gasoline as the rings should seat in much less than 200 miles and the oil bypass before then should be so small in my opinion as not to cause a problem ."

Most of the complaints we have received is with motors that had less than 100 miles on new pistons and rings. The typical mileage was 50... The complaints had started to slow down, but with all the internet sales of pistons and rings over the past couple of years the complaints have started back up again.

Being that the problem manifests it self through detonation, with the new rings unable to transfer the heat out of the piston, raising the octane rating of the gas used isn't a bad thing.

As small amount of "race" gas is about the best additive you can get, shy of using it straight up. IMHO the rest of the stuff sold as "performance" additives are suspect.

As an aside, we have had very good luck avoiding detonation twin pluging heads when we push the compression up in the 13 plus range. It works as well with stock compression. I think as time goes by we will see more people twing plugging their street motors that utilize hemispheric combustion chambers (Triumph).
Posted By: trumpetloon

Re: Fuel Additives - 01/04/08 3:22 am

To summarize several recent posts about how to treat a fresh engine::::: Best gas money can buy. Retard timing a couple of degrees and a tad rich until "broken in". Drier assembly, and earlier specification oils help. Cast iron rings are preferred in most instances, and last but not least; ride the thing like you mean it from the first start up. Sounds like all these years I have been doing it right... ah; serendipity!!!! laugh
Posted By: nutz

Re: Fuel Additives - 01/07/08 3:34 am

here in new zealand they stopped putting lead in the fuel. the quality of the fuel went from very good to very bad. i found that the bad fuel burns too quick and this caused too much heat and damaged the plugs. lots of people were blaming the plugs and going to hotter plugs. this caused more problems. i found that the higher your compression was the quicker your plugs stuffed out. we found a product called techni-lube fuel conditioner. this got rid of the problem by slowing down the burn rate of the fuel.there were a lot of complaints and the fuel is now a lot better. my 650 Bonni was high compression and would stuff a plug in less than 5 miles but with techni-lube i have never had another problem. i sold a lot of this product and it never failed to fix the problem, cars or bikes. the fuel is better now and i do not run it as much but can tell you that this product works. but it is a fuel CONDITIONER not additive. hope my 10 cents worth helps
Posted By: Blapper

Re: Fuel Additives - 01/07/08 7:02 am

Techni-lube.

Thanks Nutz.

Blapper redwine
Posted By: tomterrific

Re: Fuel Additives - 01/07/08 3:00 pm

The aromatics toluene and xylene have extremely high octane and high btu (~115). These are sold as paint thinners. You can mix either with gas to raise the octane without changing the chacteristics of the gas too much. Aromatics are already in gas so not much change except octane. If you have a choice use toluene for no other reason than that is what the old turbo F1 cars used to use for such high boost and HP.

Tom Graham
Posted By: Blapper

Re: Fuel Additives - 01/07/08 5:02 pm

Cheez Tom, Mix it myself? Without instructions? I haven't go the bottle (guts) for that!

Blapper redwine
Posted By: Tiger

Re: Fuel Additives - 05/24/08 9:39 am

Quote
Originally posted by Blapper:
Cheez Tom, Mix it myself? Without instructions? I haven't go the bottle (guts) for that!

Blapper redwine
Girlieperson Alert !

Rubber gloves and Toluene are all required, rubber gloves are the most easily obtained component.
Posted By: Melbourne Metisse

Re: Fuel Additives - 05/24/08 10:28 am

Tiger's right, when they were using toluene in F1 the refuelers used to wear very heavy duty gloves, aprons and respirators.

Evil stuff. You could smell it as soon as you walked through the gate at Silverstone!
Posted By: dale karger

Re: Fuel Additives - 05/28/08 10:18 pm

the different colors of AV gas relate to the octane rating. I used to be able to tell you what each was but....been too long. as for additives ( oil and gas )... i consider the vast majority of them to be nothing more than "wishful thinking". most were used after a problem had occurred and people figured they could spend a mere $2.99 rather than a few hundred to fix it correctly. fat chance. I had shelves of different ones that made this claim or that... all in all they really didnt deliver what they claimed. for fuel additives the best ones were basic lubes. marvel mystery oil, etc. ones that provided an extra measure of upper end lubrication. some of the carb and fuel injector cleaners were good as well...but you had to watch how they reacted with the rubber seals and o-rings in the system. I have never re-assembled an engine with a "dry" top end. I just used a light coating of 30w oil and it was done. and i have never had an engine cease or take excessively long for the rings to seat. i dont see whwere dry assembly would be bad either..i just never did.
Blapper, if you put your engine together like i know you did you wont have a major problem. to use an additive to hedge your bets against a castastrophy is a waste of time here. if something is that drastic to cause it to cease or break ... miracle in a can isnt going to stop it. use a good grade of non-foaming oil and change it after a couple hundred miles. if you want use some top end lube in your gas.
Posted By: Blapper

Re: Fuel Additives - 05/29/08 6:40 am

Cheers Dale.

Blapper redwine
Posted By: Tiger

Re: Fuel Additives - 05/29/08 10:03 am

Quote
Originally posted by Britbodger:
Just as a more extreme example of breaking-in an engine:

On a fresh rebore and new pistons and rings started for the first time and broke-in my T120 with Routt barrel and MAP billet pistons during practice sessions at a road race meeting last year. At the end of the practice sessions (about 25 miles) had the throttle wide open and, of course, in my races as well.

Should mention that the bore was expertly honed with torque plate to the correct finish (by Marino's brother Terry) for ductile steel rings with 5.1/2 thou piston to wall clearance.

A subsequent strip-down revealed the bore and pistons and rings to be in good condition with evidence of good ring seating. Pistons did have slight scuff marks.

Course may have shortened the life of the cylinder, pistons and rings using this procedure but just trying to illustrate that high rpm doesn't necessarily result in seizure - admittedly with genorous piston to bore clearance.

beerchug

P.S. Also should mention that I took the precaution of using Aviation Shell 100 (50w) for the break-in as it was very hot at that particular track at Albuquerue New Mexico
That method works and you pretty much have no choice safety wise, good to walk around the pits and warn folks that you may be a little slow in the first practice sessions.

John H, I once tried to bump start a Z1000 superbike [10:1] on dry bores, the old Kawas would not select 2nd unless the crank was spinning and no way we could get it to turn over, had to put a half teaspoon of R Synthetic down all plugholes.

I wish I still had that bike.
Posted By: trumpetloon

Re: Fuel Additives - 05/29/08 7:49 pm

For anyone considering "aromatics" as a fuel additive: have you sealed your fuel tank? Will your choice of paint stripper/ octane enhancer turn the liner into fuel system stop flow? Completely plugged carbs will cause all sorts of drama. And a certain walk home.
Posted By: Ibsnortin

Re: Fuel Additives - 05/31/08 8:14 pm

Hey Guys,

The key to break in, especially with the 3 piece oil ring is heat. When I raced Karts we used a cylinder head temperature gauge to tune on the fly (varible main jet), I started using it on all air cooled engines. It's just a ring sensor that locates between the plug and head, in place of the compression washer. Tapered plug? Never thought about it.... All the other stuff about additives and dry and all I can say is, metal on metal needs sliperage. All the wives tales have pieces of truth but an engine assembled correctly with assembly lube and white grease in the ring lands and other strategic places give me long and reliable engines. One quirk I do have is running a fan on the engine and running it on the lift until it's been at operating temp for a couple of minutes or so before riding. I listening for the engine to "loosen" a little before I put it under load.

I was a Triumph mechanic in the South when the short rod 750 came out in 1973. That summer they were gaulding pistons left and right (pun intended). What was causing it? Every one was the result of riding two up on a Sat or Sun afternoon, 95 degrees, less than 500 miles. That about the time the idiots were infiltrating the shop and no amount of repellent...I digress.

Mike
Posted By: Alan in TN

Re: Fuel Additives - 06/06/08 1:21 am

Blap,

I concur with Tom T about the aromatics bumping the octane rating. You can search Google and find sites that will give a ratio of quantity to increase in octane rating. I can go to my Sherwin-Williams store and buy 1 gal or 5 gal quantities (although you probably don't have this store in Mayenne but a paint supply house would have it). As I remember (vaguely) it seemed like about 10-15% by volume of toluene would get the rating in the low 100s. Provided your tank insides and fuel hoses can take the toluene without problem IMHO this would be the simplest approach to get a real octane boost.

To go off on a tangent briefly: adding ~1-2% acetone can give a bit of boost in the vapor pressure area if your gas doesn't vaporize quickly. There are some claims of acetone benefits in giving better overall burn but this may be a pipe dream.

My 2c

HTH

Alan
Posted By: saxon7

Re: Fuel Additives - 06/07/08 12:31 pm

Picture of the rear head of my old 860GTE. I was running it on premium unleaded with an additive. You gentlemen can draw your own conclusions.
[Linked Image]

Sean.
Posted By: ozzman

Re: Fuel Additives - 06/08/08 6:19 pm

speaking about double plugged heads...... i think that is one of the best things to do , and i think it should be a standard thing on more bikes then it is.

i have a 2000 HD sporty 1200S the "S" stands for sport, they dont make them anymore. but it came stock from factory with double plugged head, higher 11 to 1 compression, and i think bigger cams then any of the other 1200cc sporty's

the up side to it is where my friends with 1200C, or 1200R sporty's get 50MPG i get 70mpg, with a best so far of 84mpg. i pull a trailer with mine, packed with camping gear and still can get 10 mpg more then them and they are not pulling a trailer at all, and still pass them on an up hill if wanted to...lol
Posted By: RPM

Re: Fuel Additives - 06/09/08 1:25 am

Just ordered some rings from Total seal. My guy there told me about a product they sell called DRY BREAK. I have not got it yet but he explained that it is a powder that you put on the clynder walls with light oil to hold it in place. It is supposed to help bed in rings quickly on race motors as must of us racers do not have time for careful running in. Should have the bike back togather by next weekend. I will let you know.
Posted By: RPM

Re: Fuel Additives - 06/09/08 1:28 am

Sorry got the name wrong, check this out. http://www.totalseal.com/Tools.aspxy
Posted By: phantom309

Re: Fuel Additives - 06/09/08 3:30 am

Keith, site didn't work for me but I think it is the same stuff we use called quick seat by totalseal. it comes in a little thimble that will do like 4 v-8's.I think it does well but have no proof.
Posted By: Blapper

Re: Fuel Additives - 06/09/08 6:01 am

Try:

Click here then use the drop-down to find quickseat.

Interesting stuff there. Gapless rings anybody?

Blapper redwine
Posted By: phantom309

Re: Fuel Additives - 06/09/08 12:55 pm

Ive run total seal top, total seal middle,and now no total seal and they have all sealed up great.Does that help. :bigt:
Posted By: Blapper

Re: Fuel Additives - 06/09/08 4:00 pm

It does Tim, Thanks.

Have you tried the gapless rings at all?

Blapper redwine
Posted By: phantom309

Re: Fuel Additives - 06/09/08 5:29 pm

Yes Im saying I can't notice a differance in ring seal either way.Im not saying they don't work, good rings seem to seal great anyway.Now if you had a stock ring cut for a total seal it would be way better. :bigt:
Posted By: dale karger

Re: Fuel Additives - 06/09/08 6:23 pm

there was a thread about ring gaps and the myths of: too large a gap and aligning the end gaps ( since they do move and and not pinned into position ). it was interesting reading although i still cant bring myself to not arrange the end gaps in the traditional way. so might be worth the search if if you were thinking of going gapless.
Posted By: Alan in TN

Re: Fuel Additives - 06/10/08 12:20 am

I am partial to the Deves brand of rings. When I raced an Austin-Healey Sprite many moons ago I was introduced to them and they performed exceedingly well all the time. I think everyone I knew racing that class of car used Deves. They sealed quickly (of course the hone job was done in accordance) and never had a problem with them. I wish the rest of the motor worked as well as the Deves rings but the Brits did not do such things as crank counterweights, etc. To get a bullet-proof motor in the 948cc H production class would cost approximately $4K in 1970s. My time in this lasted about 18 months due to $.

The Total Seal technique sounds very interesting. I was wondering how it affects the oil during this initial running. Would it scratch the bearings or not?

If you don't mind my asking, Ibsnortin, where in the South did you work? Also, did these pistons in the new Triumph engines gall because the engines were running hotter than usual, were new and if they rode 2-up was the engine lugged or run at lower than ideal RPM?

My 2c

Alan
Posted By: RPM

Re: Fuel Additives - 06/10/08 4:27 pm

We have used gapless rings for many years. Ed Mabry used them in the worlds fastest Triumph. A double engine blown Trident. Top speed 252mph.
John are not also lowering the compression when you double plug a head? Especially when they use 14mm plugs. If so is it the dual plugs or the lower compression that stops the denotation? Food for thought.
Posted By: John Healy

Re: Fuel Additives - 06/10/08 7:48 pm

"The key to break in, especially with the 3 piece oil ring is heat."

Without getting into a dissertaion, in my mind the key to break-in is matching the cylinder finish to the rings used, proper cleaning of the bores to remove embedded stone bits left by the hone, appropriate cylinder lubrication, and generating enough cylinder pressure, by initial loading of the engine during mild to moderate acceleration, to force the rings out against the bores hard enough to seat the rings. I don't look at heat as my friend during this process as it increases the chance the motor will detonate.
John
Posted By: HawaiianTiger

Re: Fuel Additives - 06/10/08 8:16 pm

The chances of overheating your motor during break-in is greater than at any other time in your motor's life. It only takes one incident of overheating to dramatically affect many components of your engine and ruin its efficiency; ie. iron rings will collapse and lower compression. Those who propose to "ride it like you stole it" are doing everyone a diservice. Even those who stand to benefit from selling more engine parts will advise differently.
The most experienced mechanics that I have known have always given the same advice that John Healy has given here.
Bill
Posted By: RPM

Re: Fuel Additives - 06/10/08 10:22 pm

The last two post are o so true. Go to great length to get the timing real close before you start it.
Posted By: phantom309

Re: Fuel Additives - 06/11/08 2:38 am

Hope to see ya at grattan in a few weeks I leave in the morning so drive safe.Been talkin to the yamaha guys and they are thinkin they might have there hands full. :bigt:
Posted By: Blapper

Re: Fuel Additives - 06/11/08 6:22 am

This thread has been more useful during its second life than first time around. Perhaps I should have called it how to avoid detonation instead of coming from the octane boosting angle.

John and Bills posting just above are particularly useful, but (RPM) -

Quote
Go to great length to get the timing real close before you start it.
- easier with points than a boyer methinks, but I will be trying hard. Any pointers on real precision with this point?

Good stuff, thanks.

Blapper redwine
Posted By: John Healy

Re: Fuel Additives - 06/11/08 3:11 pm

Actually Blapper, we used a Boyer Micro-Power on both of our old race bikes and you can get withing a couple of degrees sighting the magnet screw through the hole in the plate.

Of course it helps that we have probably set-up a thousand or more BSA auto advance units which require a similar crude alignment during installation.

Like anything, practice is essential.

John
Posted By: Blapper

Re: Fuel Additives - 06/11/08 5:12 pm

Good job I am used to steep learning curves then!

Thanks chaps.

Blapper redwine
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