Alp Sungurtekin has built the world’s fastest unfaired Triumph 650.
 |
| Alp Sungurketin's new Land Speed Record pre-unit Triumph 650, timed at 172mph, using nitromethane breathing through new Burlen Amal GP carbs. |
Over the past few years, Bonneville seems determined to reclaim its lakehood, to the great disappointment of speed fans who’ve traveled the globe to test their metal against the clock. The Speed Trials have been cancelled several times, so last weekend the SCTA - hallowed sanctioning body of speed - held its first ‘Mojave Mile’ event at the Mojave Air and Space Port airstrip, to allow all those revved-up teams a chance to redeem their substantial investments. The Mile is different from Dry Lake top speed runs, organized more like a solo drag race over the 12,500’ runway used by the Space Shuttle. There’s another ‘Mojave Mile’ event which is open to all comers, but this SCTA event was only for Land Speed Record machines which fit the appropriate specs/regulations, and fills the gap left by a wet early-August Bonneville. With no spare real estate for a typical speed run, riders are WFO from the start line, with their speed measured at the end of the run.
 |
| At El Mirage dry lake |
Among the Mojave competitors was Bonneville regular Alp Sungurtekin, an Industrial Designer who has developed a pair of pre-unit Triumph twins into the most potent examples ever built for speed. I met Alp at end of the 2013 Bonneville Speed Trials, where he agreed to sit for a few ‘wet plate’ portraits. His first machine, based on a 1950 iron-head Triumph 6T Thunderbird, is legendary for recording 132mph at Bonneville, with a two way average of 127.092mph, making it the world’s fastest unfaired 650cc stock-framed Triumph in the Vintage gas class.
With the experience gained from his success, Alp built a totally new bike in 2014. “I’ve been designing this Special Construction-class bike for 2 years, thinking it over and drawing it out on the computer, and started building it in November 2013. The frame and all components were finished in March 2014 - it took 4 months to build, and was ready for the May races. My first test that May was bolting the 1950 engine into my new frame, and the bike went 139.226mph, the A-VG record, and that June it recorded 140.2mph.”
As seen in these photos, Alp’s new racing frame is built to keep the rider as low and close to the engine as possible. As a result, it’s a tiny machine, with the engine sat well back, and a very short final chain run. The engine plates were built of ½” thick 6061 aluminum alloy, which were hand cut, as Alp has no milling machine. The engine and gearbox form a structural part of the frame with their substantial engine plates.
 |
| Alp with his crew chief/girlfriend Jalika, and the 1950 Triumph he's ridden to 132mph (photo by Adam Bendig photography) |
“I have a nice 1958 Buffalo Forge Drill Press that I used like a mill to smooth out the edges. Took forever, little by little. I always fabricate my prototypes by hand and test them on the race course, but all the parts that I build for my clients are CNC or waterjet cut. The frame is very accommodating; its designed to ‘complete’ the rider’s body. It’s not just about the right weight or geometry, it gives a really good weight ratio distribution for maximum traction. Another feature of the frame is adjustable axle plates that make it possible to change the ground clearance and wheelbase. It’s different ergonomically, the difference between a land speed racer and a drag bike. The sitting position won’t let you take off instantly.”
Alp’s Vintage-class iron-head 1950 Triumph Thunderbird uses the original Triumph engine cases, barrels, and that single-carb iron cylinder head, and runs on gasoline. After recording 132mph with that motor, he began work on a new engine with an all-alloy top end and twin carbs, to compete in the Special Construction “A” class. The twin-carb alloy head is post-1956 (it's a '64 head), so is ineligible for the Vintage class, but runs in the 650 A-PG/F class. Aftermarket cases are allowed in this class, and Alp is sponsored by Thunder Engineering, who supplied beefed-up cases and rods. The engine was designed to run on Nitromethane, which gives tremendous power - a supercharger in liquid form - but is known to reveal any lubrication or heat dissipation issues in a spectacular fashion. “The Nitro gave me clutch problems initially, but the good thing is I didn’t blow up the engine. My Vintage Triumph, running on gasoline, puts out 58-60hp and will hit 140+mph. But many tell me with the Nitro, my later engine probably produces more than 140hp at 160+mph.”
“I first tried the new all-alloy engine in the 1950 frame; running on Nitromethane we hit 149.279mph. That’s with a stock Triumph frame! But I didn’t realize that I’d bent the frame, and the rear fender mount shredded the rear tire and slowed me down – I was on my way to 160mph. The existing record was set in 1995 by the Tatro Machine Special Harley-Davidson – Many fellow SCTA racers told me he blew up many engines to get that speed. He heard that I’d broken his record, and is coming back in October!”
“With the alloy engine in the new frame, I was recorded at Mojave doing 169.1mph -within a standing-start mile, with an exit speed of 172mph. As you know, we’re running a pre-unit 650cc open-class motorcycle with no fairing! This is a speed no other naked vintage or pushrod 650cc motorcycle has ever achieved in the history of Land Speed Racing. Our speed is faster than the 650cc/750cc partial streamline APS-PG/F bikes and 750cc / 1000cc open pushrod ‘fuel’ bikes as recorded by any sanctioning body – SCTA/AMA/ECTA.”
“The success of a racing bike is the whole package, not the parts. I designed my frame for this engine, and I balanced the engine and crankshaft for this frame. Howard Allen, who used to race at Bonneville and El Mirage in the 60’s/ 70’s with Triumphs and Harleys is one of my greatest inspirations, he was always there when I needed help. For speed, my cylinder head is the key. Doug Robinson, builder of the BMRRoadster (the world’s fastest naturally aspirated roadster at 290mph) told me the only secret to speed is how you get the air in and out of the cylinder head – it’s a pump. I’ve probably redesigned and built between 15-20 heads in the past few years; how I modify them is probably my only tuning secret. I’m using NOS cast pistons (which I wouldn’t recommend), buying them oversized and shaping them by hand – they look really funky and organic.”
“We had some interesting problems – the special construction frame has a rake of about 39deg with about 4-5” trail; it’s meant to go straight at high speed. The problem showed up while under load, wide open; the runway at Mojave isn’t flat, like Bonneville, it has a crown and the bike pulled to the right, so I had to slow down several times, just trying to stay on the course. This is a rigid frame, and on this course it bounced like crazy! El Mirage and Bonneville are much nicer without the paving. Bonneville is truly flat; I believe going straight is still better with a hardtail frame, even in the semi-saturated spots - it still wants to go straight. On the runway, without suspension, every time there’s a bump it pushes you to the side, and the very center has a seam in the paving, which is pretty dangerous at 150mph. The course was tough, but even so, the bike was still pulling at 172mph; don’t be surprised if I do 175mph, unless I destroy the bottom end!”
 |
| How low, how small can you get? Not much of either, in this case. Alp spends much time and research on cheating the wind, one of the secrets of his success. He doesn't need a wind tunnel, but has developed a system for very accurate feedback, measuring the effect of minor position changes on speed. My lips are sealed! |