As the Facebook Admin and webmaster for Bonneville Performance I get to see some pretty cool photography from Triumph Motorcycles. Below is a sweet photo used in a 2-page ad placed in Cycle World Magazine by Castrol, a major partner and sponsor of Triumph’s racing efforts.
The race machine in the photo was built by Bill Gately of Bonneville Performance, owner of the Triumph factory sponsored AMA Pro Flat Track racing team featuring rider Mikey Martin (#91).
The spec’s on this racing “Super Tracker” are incredible!
What I have learned is that Bill starts with a stock factory Triumph Scambler/America/Speedmaster 865cc engine. This engine is essentially the same engine in my 2008 Bonneville (360 degree crank) but with a 270 degree crank and a few other minor differences. The main reason for this is for the “thumping” sound and maybe a bit more torque in the lower RPM’s. Every modification Bill makes on this 270 degree race engine, can be made on the 360 degree version as well.
Bill completely rebuilds the engine with a new re-machined crank, Wiseco pistons, and Carillo rods to increase the displacement to 995cc, just under the 1000cc limit for AMA Pro Flat Track racing. He also turns his own high performance twin cams, and ports the heads for 2mm larger valves.
Once the engine is rebuilt, he adds custom billet manifolds and twin Mikuni flat side racing carbs on the intake side, and custom 2 into 1 headers and free-flow exhausts on the outflow side. A Barnett clutch , oil cooler and pressure gauge are added along with many other high performance items. All of this effort adds up to 104 HP at the rear wheel, and 87 ft. lbs. of torque!
The frame is custom designed by Bill and built from chrome moly. A modified Yamaha front fork suspension and a racing-adjustable mono-shock rear suspension are added. These features along with lightweight alloy wheels are the main reasons the entire bike ends up weighing only 350 lbs! That’s 100 lbs. lighter than my stock Bonneville!
Friends, I have seen and heard this racing bike up close, both in the pit area on race day, and on the flat dirt track and I can tell you as a Bonneville owner and enthusiast, you’ve never heard anything like it!
Amazingly, you can also buy a street legal version of this bike from Bill called a Bonneville Performance Street Tracker 995, for only $26,500.
You should seriously consider joining me at an AMA Pro Flat Track race event this coming season, and grinning from ear to ear with me!
— Randy
Randy Hi, Happy New Year. Look, excuse my ignorance, but I often hear reference to 270 degree crank, and 360 etc, but I am unsure what it means? I have a 2005 Thruxton with a 360 degree crank, I think it means there is a full circle of the pistons before it fires? Please explain? Mike
Hi Michael,
Happy New Year to you as well! Enjoy your summer down there… we are in the midst of an arctic freeze here in Chicago… -15 degrees(F) today… that’s -26 C!
You know, yours is a good question… one which I needed to research a bit more myself. I do remember asking Bill this question at the race track and he said “because it sounds more like a Harley.” I’ve also read comments that Triumph itself published a statement that the 270 degree engine was developed for the US market because it sounded (thumping) more acceptable here. Some people believe it gives a bike a bit more torque in the lower RPM range, sacrificing some top end. Whatever the case may be, I found this very helpful MC Resources web page that explains the topic in language I understand. Hope it helps you too! http://mcresourcesusa.com/TechNotes-270vs360.html I still personally prefer the sound of the 360 degree engine!
Just another post, I would be scared to ride that bike of Bill Gately’s!
Well, just the SOUND of it is scary! 🙂