Burt Munro In His Own Words

For years I have corresponded with enthusiasts from many parts of the world. No letter has equaled that from Burt Munro of New Zealand, whose enthusiasm, persistence, ingenuity and determination is both fascinating and inspiring. Here is his letter dated March 21, 1970, which has been edited slightly as it was a bit rambling! It was written over a period of a couple of weeks during breaks from working on his Indian and Velocette. - John Andrew

Part II
For this year I have made the new cylinders and pistons to the largest bore ever, it is now 3.19" x 96mm giving 60.54ci. For eight years I have carved out new rods, cylinders, pistons and cams, and work full time on either my 1936 Velo or the Indian. For 10 years I have worked 16 hours a day in the shed and was told to slow up a few years ago and now, I only work 7 days and about 70 hours a week. The flywheels I have made from a 5" axle hammered out under a steam hammer. I just finished the new pistons. I had these eight heat treated for the first time. I had the crank in the 1928 Scout turned down to 3/4" and then sleeved. I make this from oil hardening steel and squeezed on and pulled up with standard nuts. I left the taper on one end and made another taper with 3/4" hole in it to fit the drive of the flywheel. The rods of course now have a bigger eye and smaller rollers. The mainshafts, up to about three years ago, were standard, about 13/16" with four sets of caged genuine Indian rollers 1/4" x 5/16" running on the shafts. Well, as speed mounted-up over the years I got visions of them breaking and in 1957 I had a new pin, crankpin that is, given to me in Springfield, Mass. on a visit to Indian. This I fitted to the timing side with big end bearings. Then the drive side looked so thin. I looked around and had a spare gearbox mainshaft. So I ground the four outside splines off it and made up two driveshafts from it. Then I had them re-hardened and ground locally. I bored out the taper in the flywheels with my 3 1/2" Myford lathe. By the way, I completely made my new cylinder heads on the same lathe. The only change is to cut about 1 1/4" off the gap in the bed of the lathe for the flywheels. This probably weakens the lathe a bit but I still work it every day, and have since it was new 22 years ago. I am on my second set of (lathe) back gears, worn out about 12 years ago, and my third lead screw is now badly worn.


Burt's Munro Special in its ongoing development, circa 1943

Cams I made by file and saw since 1926 but now have built a cam grinder and make them in pairs. I spent 800 hours in 1963 making the engine into a four cam setup. After I timed them, I pin them to the 1/4" hole in the standard cam wheels on the Scout. Cam followers are filed from axle steel and I make a fork to take a 3/4"x 1/4"

roller running on needles, and an oiler to keep a good flow from the 1933 Indian oil pump. This was given to me in 1956. This I modified to pump oil to the big end. At this time I made my steel flywheels.

The famous record-breaking Munro Special. The workshop and un-mowed lawn look as they did in the movie. Note on the back reads, "Munro Indian in the second streamline shell made of fiberglass."

The 1920 Scout frame and my third streamliner shell are still in the U.S. The first full shell I built took me five years to hammer out of the sheet aluminum. I could only work at it when I had my bike ready for testing, then, if it blew-up I would work on the engine until it was running again, then hammer away on the shell again. Or I would suddenly think of some new scheme to get more speed. Of course these brain waves often made it slower, or just more blown parts. By the way, I have read of E. Fernihough's death and perhaps I can offer a reason for him running off the road that day. I have several times had similar experiences caused by a side wind of only two - three mph. If one is traveling at over 180 mph as on most occasions with me, the bike steers over to one side but I start to steer it back at once. But I have had it go 12 feet over the outside of the black line before getting it back to the center of the track. This I have known to take about a mile from start of swerve to be back on center of track. If this were on a road of course there is no chance of survival.

The first shell I took with me to Bonneville in 1962. It was the second I had built. The first one, of aluminum, was too hard to ride, too neat a fit and I had a great difficulty shifting the gears. I modified it and used it as a mold for shell number two of fiberglass. I had my first run on it at Bonneville in 1962, and was ordered to have a test run with the officials following in a car. It just veered from side to side at all speeds. I said to myself, "I may as well ship it back home, they will never let me run a thing like this." When they came up with me they said, "It handles ok." I said, "What!" They repeated it handled good.



Well for the next five or six years I had some of the worst out-of-control rides on record. The worst was for five miles late in 1962 when in an effort to stop wheel-spin at 160 mph I built a 60 lb. lead brick and bolted it in front of rear wheel. By the time I got to the three mile marker the top of the shell was swerving five feet and wheel marks were five inches wide and snaking 30 inches every 200 yards, when we measured it later. Well, when you figure you can only die on the next skid you try anything. So I wound it "all-on" for another one and a half miles. Then, when I found out it would go on like that forever, I rolled it back out and got it stopped. When the gang arrived and found me laughing and asked me the joke, I said I was happy to still be alive. The cure is to sit up and let the body strike the air. This shifts the center of pressure back behind center of gravity. I learned this the hard way. The lead brick should have been in front of the front wheel and shell higher off the ground. At the rear, the air packed under the tail and lifted weight off rear wheel, thus caused wheel spin.



More specs. I have mods in the clutch. The standard Raybestos plates are long gone and I have 17 standard steel plates, hardened and ground. I fit 24 standard clutch springs giving a pressure of 1360 lbs. on the pressure plate, and the standard thrust race and withdrawal screw haul this free for freeing and gear changing. I have a left hand lever and wire to operating arm and a small fort assist lever on the clutch worm shaft. I only use this for low gear engagement during test runs without the shell. Over the years I made four chain drives having finally ground helical teeth off the clutch body and filed out 46 half inch pitch teeth by hand and now run a three-row chain on a 22 tooth engine sprocket and still the 46 tooth clutch sprocket. This, Reynolds in London, told me 15 years ago, would be impossible and would never work but it has run for the last 35 years or so, in 10 SAE oil. The gearbox is original but I was unable to get a new sliding dog. On a visit to an old acquaintance in Sydney in 1948, he had bought out Mr. Biden's stock on Indian parts. I bought a set of 1916 Power Plus Indian gears, lay shaft cluster and sliding dog. The cluster I shortened to 3/8" and have run on these for the past 22 years.

Cylinders I usually make from very old city gasworks pipe, cast-iron condemned because of very large pits. I manage to get short lengths without too deep marks and because of the thickness, about 1/2" to 5/8", I have enough thickness for a base. The barrels are old pistons melted in a small pot on the two-gallon can furnace I use for melting-down to make pistons. The muff casting I turndown in the Myford lathe, bore undersize then heat-up with a blow-lamp and drop onto the liners. Pistons I redesign every year and make about half a dozen or so and take them with me to the U.S. for spares. Some years I have used every one and even welded up burned-out ones. When Jim Enz and his wife wanted to help me with fuel I said I would like to try alcohol and they brought me five gallons of the best brand, Mickey Thompson alcohol. Boy, it sure was the best piston burner! I guess it had Nitro or TNT in it. Every run, the pistons vaporized. No alloy heads on my heap.


This is the last photo taken of Burt with his Indian Special. Shot in December, 1977.

Carburettor is 1924 Indian Chief. I have sawn a cut full length on top of it, bent it out and welded a piece of brass in the gap and ran it in normal position with a T shape manifold made from 1 3/8" steel tubing. I have turned five carbs for my bike since 1927 when I swapped the Schebler H for a Schebler De Luxe. All the others I have tuned and modified have been Schebler De Luxes as fitted to Indians made later than mine.

This year since arriving home from the U.S. five months ago, I have put in 560 hours on the Munro Special. The main jobs were two new alloy rods - two weeks, two new cylinders and barrels - one week, eight new pistons (and much work on old dies for the same) - three weeks. I am making two new sets of cams for this year. Making a 180 degree Bosch mag into a 42 degree by making a new brass cam ring. From an old ball race I made the two magneto cams, filed and timed accurately then quenched in oil. As this 20-year-old magneto rotated backwards I had to make up a drive different from the standard. This I finally got working by taking out the two idler pinions, and fitting a big cam wheel from a late model Indian. This has four teeth more than my engine and by cutting 1/8" off the base of mag and cutting into the cases a little and jamming it back and boring new holes and tapping-out the same, I finally got the drive fixed. I also made a movable shaft to run the large pinion on and thus I get a close tooth adjustment.


Burt Munro arrives at Bonneville, August 1971. "I'm 99 percent sure the hippie looking fellow standing to Burt's left is Roger Donaldson, who at the time was shooting his 16 mm documentary about Burt, Offerings To The God Of Speed." Richard Menzies. Photo by Richard Menzies.

Since finishing the above I have been testing at the beach. I have been out 17 times and had 11 blow-ups. This consisted of mostly broken pistons of older designs. I was testing out a steel rod and a new carb I had made in the last two or three years. I ran it on 20 to 1 to test the rod, then built better pistons and ran three in it, one after the other, until I had one that would stand-up to 13 to 1 compression. As soon as I lowered the compression to 13, the rod which had stood-up to all the broken pistons finally shattered the top end when I was accelerating hard in top gear at 5,500 rpm. I tore it down. The new piston was in many pieces, pin broken in half, cylinder scored, split at the skirt and hammered out wedge shape and locked in the cases. One rocker arm was broken, one twisted, one push rod broken, one buckled. Other breaks were the cam follower I had made from magnesium four or five years ago, another rocker and pushrods bent and both valves bent.



Development goes on all the time and has been full-time these last 22 years. I would like to make another DOCH set up. I still have the one I made and ran in quarter mile grass track races about 1951. This was fitted on the front cylinder. The rear cylinder was blanked off. It was just an exercise as everyone was talking double knockers at the time. It is only lately that I have had ideas to try to fit up one for the rear as well, but have so far failed to get the time needed for this project.

I pulled the head off this morning and am now starting to make two new rods from a DC6 propellor. I hope to find it strong enough. It was sent to me from Auckland as I cannot get the 70-70 or 20-24 alloy in New Zealand. I like to improve my cam design every year, carbs (just finished a new one yesterday), conrods, pistons and sometimes valves and guides when they wear a little, and of course the cylinders.

About photos, I had many over the last 40 years but most early ones were lost when my fairly-new house burned down over 25 years ago. I will have a look round. Most are stuck in books and are not available. I will see if I can get a photo of the engine but if I can't get this posted this afternoon, it will be another four days gone. I have had a quick look round but things are all over the place. I have found these two. They give a view of engine and hope it will help with these notes. It is almost impossible for me to give you a true picture of the time I have spent on my cycles. The last 22 years have been full-time and for one stretch of 10 years I put in 16 hours every day, except Christmas when I took the afternoon off.

I have a berth on the SS P&O Oriana for the U.S. on June 15th but will not go if I cannot pass the doctor.
I am yours sincerely,
H. J. (Burt) Munro

Footnote
Burt never again competed at Bonneville, due to declining health. But to this day he enjoys the distinction that his Indian is the fastest the world has seen, 190.07 mph at Utah's salt flats in 1967. Burt died peacefully in 1978 at the age of 78.
If you want the ride to continue consider purchasing these two books on Burt Munro. One Good Run: The Legend of Burt Munro by Tim Hanna and Burt Munro: Indian Legend of Speed by George Begg. Both are available from Aerostich, (800) 222-1994 or order on-line at:www.aerostich.com. They also had the movie on DVD.

Making the movie
Mike Tomas and the good folks at Kiwi (Indian) Motorcycle Company supplied the accompanying photos. Last year these lucky dogs were asked to participate in making The World's Fastest Indian on the famous Bonneville Salt Flats. Transportation and some tech support was their assignment and it seems they performed well.

The replica streamliners, yes there were five of them built for the movie, were transported from LA to the salt flats in Kiwi's big rig. Mike and the staff brought a gross of Kiwi t-shirts with them for the movie cast and crew. Smart move. These shirts soon became standard apparel on the salt.

One of the important daily tasks was cleaning and maintenance of the replica streamliners. A World War II airfield, in the nearby town of Wendover, was selected for task. The two streamliners, which were used for the racing shots, were Ducati powered. Insurance company regulations dictated "two of everything." A third machine was built for the close up engine shots and featured a Hollywood "aged" Indian Scout motor complete in every detail. Two additional "shells" were towed behind the camera trucks for the slow-speed filming. Mike Tomas mentioned that Anthony Hopkins said it was the most fun he had making a movie in over 20 years. From these images it looks like the Kiwi crew had a great time also.