The Thunder Stroke 111 has been in the motorcycle market since 2014 so I figured it’s time to take a closer look at this good looking VTwin engine.
The TS111 resembles the Indian Chief motor look of the 40s and early 50s. It’s a nice piece of modern mechanical engineering. It’s about as far advanced as one can take the traditional air-cooled, internal combustion V-Twin engine.
At 111 cubic inches, this 49-degree V-Twin motor (1811cc) puts out an estimated 78 hp @ 4510 rpm and pushes out a whopping 119.2 ft-lbs of torque according to data from the Indian Motor Company. For those of you not familiar with these types of gearhead stats, you can use the term “torque monster” with confidence to describe it.
Old-style classic inspiration
Looking at the early Indian Chief motors, it is easy to see the retro-look resemblance. I personally like the big slanted fins, the fat pushrod tubes, tapered cylinders and downtube exhaust pipes design of that 1940s era.
Let’s look inside…
I was able to take some nice cut-away photos of the Thunder Stroke 111 while visiting the Indian Motor Company booth in Sturgis this past August 2015. Additionally, the good folks at Indian Motorcycles sent me some of their CAD design images so that I could share an insiders view of the engine with all my blog fans and followers.
Cool CAD designs. I’ve added some tech notes for reference.
It’s not often you get to see what the engineers saw on their computer screens when they were designing this motor.
Imagine their excitement when asked to take a clean sheet of paper/screen and come up with a modern air-cooled V-Twin for new Indian motorcycles back in 2011. Oh, and it’s got to ready for testing and production in 24 months.
The Thunder Stroke is a fuel-injected 4-stroke 49 degree V-Twin engine with serious displacement at 111 cubic inches (1811cc).
The engine has a forged single-pin transverse crankshaft that transfers power from the big pistons (3.89 in./101 mm) during their their big 4.45 in/113 mm stroke.
Note the 2-valves per cylinder shown in the diagrams here and the three camshafts driving the parallel pushrods which in turn, bring the hydraulic lifters to life. We’re talking a really cramped mechanical design around them three camshafts.
The 111 is the most innovative interpretation of a V-Twin motor I seen in years.
As you can see in this post, the motor design of Indian’s Thunder Stroke is modern and innovative.
Big kudos to the engineers at Polaris’s Indian brand for bringing this new V-Twin to market I say.
Durability and Reliability…tested for over 1,000,000 miles according to the factory.
As indicated earlier in this post, the Thunder Stroke’s monster displacement of 111 cubic inches (1811 cc) is said to deliver 119 ft-lb of torque. The engine tops out at 5500 rpm, and delivers its power through a six-speed overdrive transmission. Compression ratio is high for your basic air and oil cooled engine at 9.5:1.
The new design, which has undergone over one million miles of testing, has a forged single-pin transverse crankshaft to transfer power from the 3.89-in diameter pistons during their 4.45-in stroke.
The TS111 is an overhead valve engine, with two valves per cylinder controlled by a triple camshaft driving parallel pushrods which activate hydraulic lifters. Yes, you read correctly…this motor has three cams that drive four pushrods that open and close two intake and exhaust valves per head.
As you can see, the design is rather cramped near the crankshaft. The motor has big cylinder outlines and multi-directional cooling fins to optimize engine cooling.
The engine is connected to a six-speed overdrive constant-mesh transmission. Sixth gear turns 3.37 times faster than first gear, leading to an easily controllable transmission that will allow a rider to remain within the power band of the engine under most riding conditions. The clutch is a multiple-plate wet design to provide smooth clutch action without undue slippage.
See the following interesting YouTube videos for additional perspective.
Indian’s introduction video…check out this video…
Here’s a factory look from the team at MotoGraphic.
My recent social media call for riders with 50,000+ miles on the Thunder Stroke 111 did not uncover such a riding pro but I did find one happy owner with just over 37,000 miles. Here is his quote:
“I have put 37,209 miles on Chieftain #873 since January of ’14 and it has been utterly reliable. I just returned from a month-long ramble across the country of over 4,000 miles, in all kinds of weather and extreme temperatures; I never once had any concern about making it home. I’ve had no clacking, no belt problems, no oil leaks, no rough running. I have put two front and three rear tires on it. Problems, such as they have been, are mostly little electronic glitches in the bike’s sophisticated electronics suite. I’ve replaced three headlight bulbs (commonly available H-4s). It has been the best bike, of many, that I have ever owned. That has been my experience with Chieftain #873.” — Randall… Source: Indian Motorcycle Forum – IndianMotorcycles.net
The Bottom Line.
There’s no doubt this is one powerful, sweet motorcycle engine…a real good looker. It even looks good in a naked Indian Chief frame as shown in my Sturgis Rally photo below.
The Thunder Stroke is a modern version of a truly classic motor. Only time and hundreds of thousands of road miles will tell if this motor has true reliability and staying power. My motorbike experience tells me that the odds of having a superior, long-lasting motor here with the TS111 are very good.
Best I can tell, the Thunder Stroke 111 engine is the new standard for V-Twin motors on the market today.
Note to Indian Motorcycle Co.
I gotta ask the creative minds at Indian Motorcycles.
Could an innovative, water-cooled crankshaft in-line four be coming in the future?
Stay tuned folks. My bet is that more innovation and excitement will be coming from the Polaris motorcycle companies in the future.
Note: Engine photos taken during my 2015 visit to the Indian Motorcycles display in Sturgis, South Dakota. CAD images and Classic Indian Chief images from Indian Motorcycles’ PR Pros. Copyrights and Trademarks are the property of their owners. No infringement ever intended. See footer of this blog/website for more information. Ride Safe Out There.