I realise I may be treading on toes here, but has anyone managed to change the "ten" on the transfer to "25" so that it is accurate for a different needle?
Donald
water transfers for 1969 featherweight
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Collector Inspector
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Re: water transfers for 1969 featherweight
No treading on toes mate....decals are what they are and suited to a model/year.Donald A wrote:I realise I may be treading on toes here, but has anyone managed to change the "ten" on the transfer to "25" so that it is accurate for a different needle?
Donald
If a different needle or jet that is internal as the owner choice then well and good... if that is an owner modification then so be it.
B
A chicken is one egg's way of becoming others
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headdownarseup
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Re: water transfers for 1969 featherweight
I think John who hosts this site and runs the main SOS site has tank stickers with the 25:1 petroil info.
But surely, if your featherweight is a 69 model, it's better off staying at 10:1 isn't it?
Jon
But surely, if your featherweight is a 69 model, it's better off staying at 10:1 isn't it?
Jon
Re: water transfers for 1969 featherweight
Thanks for that -
I'll try John on the decal front
The history of this engine (F811B for Bravo9 - gold top, Mark II ignition, Villiers carburettor) is that I got it on ebay for almost nothing, because it had a cracked block - when I took it apart, the block came away in two pieces, the bottom bit still sticking in the exhaust tube... I then put a replacement block on, having honed the cylinder and put new rings on. Then I took the head off, and cleaned the waterways
Then I started on the tank - hence the question
As a non engineer, I've never been able to understand the ten to 25 point.
From a common sense point of view, surely there needs to be enough new oil coming in (via the fuel) to replace the old oil that gets burnt off. If the engine is designed (by technical quantification or perhaps just by the good old " if it feels right it is right" approach) to continue running for a long time, without overheating and then seizing, on 10 to 1, then I do not follow how one can (roughly) halve the oil input, and still expect the engine to be happy?!!
Still, a lot of people out there are doing it, so I must be missing something obvious...any offers?
Regards
Donald
I'll try John on the decal front
The history of this engine (F811B for Bravo9 - gold top, Mark II ignition, Villiers carburettor) is that I got it on ebay for almost nothing, because it had a cracked block - when I took it apart, the block came away in two pieces, the bottom bit still sticking in the exhaust tube... I then put a replacement block on, having honed the cylinder and put new rings on. Then I took the head off, and cleaned the waterways
Then I started on the tank - hence the question
As a non engineer, I've never been able to understand the ten to 25 point.
From a common sense point of view, surely there needs to be enough new oil coming in (via the fuel) to replace the old oil that gets burnt off. If the engine is designed (by technical quantification or perhaps just by the good old " if it feels right it is right" approach) to continue running for a long time, without overheating and then seizing, on 10 to 1, then I do not follow how one can (roughly) halve the oil input, and still expect the engine to be happy?!!
Still, a lot of people out there are doing it, so I must be missing something obvious...any offers?
Regards
Donald
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headdownarseup
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Re: water transfers for 1969 featherweight
Not many people realise that the fuel/oil ratio was that way for a good reason.
A lot has to do with the crank bushes and how much oil gets distributed inside all the moving parts. The more oil there is, the more the internal parts get lubricated. (not all of the oil will get burnt, what oil isn't burnt is used for lubrication and to some degree sealing the crank cases)
The older design of crank bushes required more oil content in the fuel to deliver adequate service life and lubrication.Having said that there are a LOT of motors that have already been modified by swapping the fuel needle (or jet in the larger motors) for the later type (25:1) and still manage to run quite happily for years with no ill effect.
Motors produced before 1978 should really be kept at 10:1 as these will probably have the older design of crank bushes still installed. (you can always lean the mixture down a tad if you feel you must do this, but dont overdo it.)
After 1978 ALL motors were factory converted to run on 25:1 as the design of bushes changed from that of the earlier type.
Old engines (doesn't really matter what it is) will usually require more oil than what you might be used to.
Jon
A lot has to do with the crank bushes and how much oil gets distributed inside all the moving parts. The more oil there is, the more the internal parts get lubricated. (not all of the oil will get burnt, what oil isn't burnt is used for lubrication and to some degree sealing the crank cases)
The older design of crank bushes required more oil content in the fuel to deliver adequate service life and lubrication.Having said that there are a LOT of motors that have already been modified by swapping the fuel needle (or jet in the larger motors) for the later type (25:1) and still manage to run quite happily for years with no ill effect.
Motors produced before 1978 should really be kept at 10:1 as these will probably have the older design of crank bushes still installed. (you can always lean the mixture down a tad if you feel you must do this, but dont overdo it.)
After 1978 ALL motors were factory converted to run on 25:1 as the design of bushes changed from that of the earlier type.
Old engines (doesn't really matter what it is) will usually require more oil than what you might be used to.
Jon