Petrol additives

Peter Stokes

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I am curious to know what we think of the various petrol additives. I do not mean the ethanol problem, but the old unleaded, low-octane problem.
I have not got a Vincent anymore, but the problems are just the same on my old 750 Ducati, and the Velo I sometimes have the use of.
I have used the Castrol product (Valvemaster Plus) for some years, and it does seem to work. The engines run ok and the tappets do not need adjusting all the time, so it seems, simply, to be doing its job. We have been using these additives for long enough now, that there should be some amassed experience, and some comments. Maybe this aspect of modern fuels isn’t a problem if the additives are used – it would be nice if something was simple.
Has anyone any experience of Tetraboost, evidently a real lead additive instead of a substitute?
Thanks - Pete
 

timetraveller

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I used the Miller version of this which is also an octane booster. I found that I was having to slacken off the tappets about twice a year and when I took the heads off it was clear that the valve seats were eroding. However, be warned that what applies to one bike might not apply to others. In the Club we have a very knowledgeable member with both a PhD in automotive engineering and also a lifetime of experience with one of Britain's best known engine developers. He told me that it is possible to do a calculation including temperature, rpm etc in order to determine what the likely wear rate will be. Guess what! A Vin at about 2,000 - 3,000 rpm is just in the worst part of the wear profile and will erode it's valve seats more rapidly. Other bikes with different revs, temperatures etc might behave differently. I tend cruise at about 3,000 - 3,500 rpm, possibly slightly higher, whenever on the open road so if that is your normal usage then you can expect to get valve seat wear.
 

Howard

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I used the Miller version of this which is also an octane booster. I found that I was having to slacken off the tappets about twice a year and when I took the heads off it was clear that the valve seats were eroding. However, be warned that what applies to one bike might not apply to others. In the Club we have a very knowledgeable member with both a PhD in automotive engineering and also a lifetime of experience with one of Britain's best known engine developers. He told me that it is possible to do a calculation including temperature, rpm etc in order to determine what the likely wear rate will be. Guess what! A Vin at about 2,000 - 3,000 rpm is just in the worst part of the wear profile and will erode it's valve seats more rapidly. Other bikes with different revs, temperatures etc might behave differently. I tend cruise at about 3,000 - 3,500 rpm, possibly slightly higher, whenever on the open road so if that is your normal usage then you can expect to get valve seat wear.
Hmm ............ Officer, I have to go this fast to protect my valve seats.......... sounds like a perfectly good excuse to me.

H

ps I'm using Castrol Valvemaster. I don't know what's happening to the seats yet, but the engine doesn't seem to run any different when I top the tank up without it.
 
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Tom Gaynor

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FWIW, I've never used additives in fuel*. I did top the Vin up with Avgas (used in a race bike) occasionally, but probably haven't adjusted the tappets in 12,000 miles. When the heads were off, at 50,000 miles, after 6000 miles on lead-free, the seats were OK. The other high-mileage bike, the Ducati, 1993, may have hardened seats, but at 56,000 miles has only been serviced once in 14,000 miles.
* Not entirely true: I use 1:100 R in the 1922 Sunbeam: people like the smell, and it stops the valves sticking...
 

Alan J

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Additives.

How do, Peter!!-when lead became unavailable in petrol I put some "wonder capsule" in one Morini tank, but not in another Morini! 10 years down the line there is no difference in their performance or valve condition! I am far more worried about ethanol, however!!
 

Peter Stokes

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Thank you everyone.

Hi Alan - about time you came up here again? I was going to say that most of us don't get a chance to do a 'control' to the experiment (that is, to see what would happen if you don't do something...), but you have done one. Also I should have said that any problems with my bikes are similar to those of the Vincent, not the same as.

Pete
 

len.c

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Hi Peter,As Tom has already suggested sneak down to your local flying field and purchase some AV-Gas I use just a snifter per tank full , especially when I was racing,in fact at the MGP you could buy Avgas in the paddock so we used to bring some back with us. The problem is there are so many conflicting ideas on the effect of unleaded fuel and valve seat erosion as with the Ethanol problem ,which is probably much more serious,It's probably a case of proceeding with caution,and hoping some one far more intelligent than me can come up with a viable solution .Good luck Len.c
 

Peter Stokes

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Hello Len,

A good idea, there is a local flying club, and I am aware of avgas, but it has never occured to me to try to buy some. I have had some trips in their Cessna (only sitting alongside the pilot) which is great fun. I admit to having a little 'go' in it, I found I could keep it in a reasonable (three dimensional!) straight line, but it was going round corners that was the problem!

Pete
 

len.c

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Hello Pete,Did you read the VMCC mag? there is a note from Leslie Thornley, who mentions a product named Ethomix which apparently originates in America and is supplied by Frosts, renowned for there restoration products,seems quite promising.Regards Len.c
 

mercurycrest

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About twenty years ago, when the EPA forced the USA to use only unleaded gasoline, we went through all the same worries you Brits are going through now. Today, when you read or see of an American riding an old Vehicle, especially a Vincent, it's a lie! All our old stuff was ruined long ago. I repeat: Whatever you've heard or read, or seen with your own lying eyes is false... None of our bikes survived.
Cheers, John :rolleyes:
 
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