I'm in the process of designing a cafe racer and acquiring the parts, I'd like to use the air speed indicator from a Lancaster or spitfire (probably a Lancaster as it is also in MPH not just knots) although i could change the scale. How hard is it to set up a speedo (especially one not designed directly for this use)? I don't mind changing the internals but I have never calibrated one before.
Air speed indicator conversion
1 - 20 of 27 Posts
Wanna know how you can tell you are dealing with a schmuck who has no idea what he is doing? This. Read the initial post.
Ok Benny, I'll oblige.
First off the sending unit for an airspeed indicator on an airplane is called a pitot tube. remember that phrase: pitot tube. in order to use this you will need one. One from a spit usually sells for between $160 and $230 just because it is from a spitfire. I have never seen one from a lancaster for sale.
First disappointing part - you can't use your gauge to convert to this type of reading. You are going to need the whole assembly - the pitot tube and the actual airspeed indicator (they are a matched set). If I had to guess what this would cost to use one from an actual spitfire I would put it at $1000 all said and done not including installation.
Second disappointing point - it needs to be in clean air. This means you can't have it hidden someplace on the bike. If it were me and I was concerned with how it functions I would have it on a 2 foot stalk coming out the top of the headlight housing, i.e. it would be the most forward thing on the bike. I would sugest the front fender but you would have to run it with the lines exposed.
Thrid disappointing point - it isn't road legal. Ever been in a taxi-ing aircraft? the gauge doesn't read below 10 kts. Oh by the way, airspeed indicators are in KTS, not mph (although some do have ground speed markings on the gauge as well).
Fourth disappointing point - airplanes are 24 volts. bikes are 12 volts (sometimes 6 volts). getting one to work correctly would require some creative electrical work (of which I have no idea).
Here is some saving grace - the way they measure speed in light aircraft hasn't changed since the airplane was invented. That means you can probably salvage all you need off a Cessna 150 or a piper cherokee and it will cost you a fraction of the cost, work better than 40's junk, and nobody can tell the difference except really good airplane buffs.
Why is it a stupid idea though? because it is adding 15 lbs of crap to a bike just to measure speed in a way you can't actually use. I mean if you were racing at bonneville and were expecting to be in the 200mph club, that would be one thing, but it sounds like you just want to impress everyone in your local starbucks' parking lot.
want something better? how about you call up VDO and ask them about their automotive gauges that look like airplane gauges and have them make you a custom one that works with an electric speedo unit. Then find an electric speedo sender off a modern sport bike that fits your bike.
Ok Benny, I'll oblige.
First off the sending unit for an airspeed indicator on an airplane is called a pitot tube. remember that phrase: pitot tube. in order to use this you will need one. One from a spit usually sells for between $160 and $230 just because it is from a spitfire. I have never seen one from a lancaster for sale.
First disappointing part - you can't use your gauge to convert to this type of reading. You are going to need the whole assembly - the pitot tube and the actual airspeed indicator (they are a matched set). If I had to guess what this would cost to use one from an actual spitfire I would put it at $1000 all said and done not including installation.
Second disappointing point - it needs to be in clean air. This means you can't have it hidden someplace on the bike. If it were me and I was concerned with how it functions I would have it on a 2 foot stalk coming out the top of the headlight housing, i.e. it would be the most forward thing on the bike. I would sugest the front fender but you would have to run it with the lines exposed.
Thrid disappointing point - it isn't road legal. Ever been in a taxi-ing aircraft? the gauge doesn't read below 10 kts. Oh by the way, airspeed indicators are in KTS, not mph (although some do have ground speed markings on the gauge as well).
Fourth disappointing point - airplanes are 24 volts. bikes are 12 volts (sometimes 6 volts). getting one to work correctly would require some creative electrical work (of which I have no idea).
Here is some saving grace - the way they measure speed in light aircraft hasn't changed since the airplane was invented. That means you can probably salvage all you need off a Cessna 150 or a piper cherokee and it will cost you a fraction of the cost, work better than 40's junk, and nobody can tell the difference except really good airplane buffs.
Why is it a stupid idea though? because it is adding 15 lbs of crap to a bike just to measure speed in a way you can't actually use. I mean if you were racing at bonneville and were expecting to be in the 200mph club, that would be one thing, but it sounds like you just want to impress everyone in your local starbucks' parking lot.
want something better? how about you call up VDO and ask them about their automotive gauges that look like airplane gauges and have them make you a custom one that works with an electric speedo unit. Then find an electric speedo sender off a modern sport bike that fits your bike.
Oh, and I shouldn't have to ask this but....what bike are you planning to put this on?
oh and I probably shouldn't tell you this as it will only encourage you but....some of the cessnas from the 40's to the 60's are 12 volt. I have no idea what the amperage draw is but some of those have heaters you can delete which should reduce the draw.
airspeed indicator itself is the expensive part. Even ones for cessnas are $200-$500 for working certified ones. Maybe you can find a working one that is not flight certified for less but then you have a gauge running on borrowed time.
oh and I probably shouldn't tell you this as it will only encourage you but....some of the cessnas from the 40's to the 60's are 12 volt. I have no idea what the amperage draw is but some of those have heaters you can delete which should reduce the draw.
airspeed indicator itself is the expensive part. Even ones for cessnas are $200-$500 for working certified ones. Maybe you can find a working one that is not flight certified for less but then you have a gauge running on borrowed time.
out of curosity I looked up WWII ASI's and non flight ready ones could be had for the low price of 125 BPS. Of course they were out of a Bulton Paul Defiant and not a spit or lancaster, but still that is shockingly low to me. They also don't begin to read until 200 mph and max out at 360mph. Even if you mounted one to an R1 it wouldn't make a difference.
This isn't a new idea either. My father had an aircraft mechanic friend who had one attached to his 1990 zx10. It was a cessna 140 unit which means it started running at 20 kts and ran all the way up to 140 kts. He got his money's worth out of it in entertainment value but he kept the stock speedo.
aircraft spruce is your friend if you still aren't discouraged.
and just in case I am reading this wrong and you want to know how to convert a spit ASI to read off a cable, the short answer is you can't. YOu could gut the housing and install your stock speedo guts but the face needs to travel. And by the way those old warbird faces are painted with uranium and handling one is pretty toxic.
This isn't a new idea either. My father had an aircraft mechanic friend who had one attached to his 1990 zx10. It was a cessna 140 unit which means it started running at 20 kts and ran all the way up to 140 kts. He got his money's worth out of it in entertainment value but he kept the stock speedo.
aircraft spruce is your friend if you still aren't discouraged.
and just in case I am reading this wrong and you want to know how to convert a spit ASI to read off a cable, the short answer is you can't. YOu could gut the housing and install your stock speedo guts but the face needs to travel. And by the way those old warbird faces are painted with uranium and handling one is pretty toxic.
Joined
·
1,908 Posts
Hey Geeto - can you find me a turret off a Boulton Paul Defiant? I want to bolt it up to my Honda Pilot so I can clear traffic out of my way on the way into work...
Thanks!
Jim
no, but preston tucker (who invented the tucker turret and the tucker torpedo) had one mounted to his combat vehicle which he routinely used. The Tucker turret was forced licensed to the government for use on b-17s and b29s. Yet another way the government screwed him.
if you need turret parts:
WWII Turret Parts For Trade
if you need turret parts:
WWII Turret Parts For Trade
Joined
·
1,908 Posts
Hey I like the bomb fins!
FINS
Wonder if I could glue them to the old style cork half helmets and triple my money selling them as vintage speed helmets? Call them "Da Bomb" helmets...
Joined
·
7,140 Posts
Me too, they would look cool on the nitrous bottle in my car. "No officer, it's not nitrous is a bomb"
Joined
·
7,140 Posts
The set up on that bike looks a whole lot simpler than the nightmare you described earlier.
Joined
·
4,123 Posts
Here you go, $10.00 airspeed indicator
New Green Science Windmill Generator by Toysmith | eBay
New Green Science Windmill Generator by Toysmith | eBay
yeah it is stupid simple if you don't want the authenticity of it being from a 400+mph WWII British fighter. It is when you reach for douche status then shit complicates exponentially.
It is also of limited usefulness. About the only thing it is good for is assessing the accuracy of a headwind using your speedo gauge of dubious accuracy to begin with. I can think of only two instances where such information would be useful - land speed (where you are comparing it to a more accurate speed meter like the clock of a GPS speedo), or when you are hypermiling (ie getting the most mpg out of your vehicle) and little things like windspeed have a big impact.
Joined
·
672 Posts
too be honest it seems to be an exercise to install something different(which is fine). But i do not think it will ever work correctly since there are too many variables to be accurate at all speeds on a regular basis and you could spend your time and money on making something else for your machine that will actually add to it's performance in suspension,engine,handling,etc.
funny story 44warf, too bad they did not have the pitot covers on them....
have a good one,joe
funny story 44warf, too bad they did not have the pitot covers on them....
have a good one,joe
1 - 20 of 27 Posts
