A great analog throttle upgrade

If you’ve never looked at the fun-side grip on your motorcycle and wondered how you can make it better, or how it can make you better, you might want to consider the Motion Pro Rev2 and what it can do.

Replacing the entire throttle assembly on my motorcycle isn’t exactly a modification I make all the time. They twist. I go. Simple. Well, until they don’t.

As I prepped my bike for a fun weekend with huge fuel tanks, I noticed a funky feel inside my throttle. Further inspection revealed a destroyed inner assembly to my stock 2013 KTM 500 EXC’s throttle.

My current throttle was broken, for sure, certainly unsafe and nearly inoperable. But I wondered if any benefits could be made in a throttle upgrade? The simple answer is yes. Enter Motion Pro.

At around $165, the Rev2 Throttle Kit isn’t inexpensive. But for what it can do to the power delivery and ride experience – not to mention what you get in the kit – I think the price is good.

The Rev2 Throttle Kit comes in a STREET/ROAD RACE or MX/OFF-ROAD version. Both kits include a complete Throttle Assembly, high-quality Motion Pro black vinyl throttle cables (designed specifically for your bike), five interchangeable throttle reels, a set of Motion Pro Grips, some stickers and nice instructions showing what each throttle reel can do and how to install the system.

The MX/OFF-ROAD kit I tested came with a special Off-Road cam reel, a Titan Throttle Tube and Motion Pro’s DirtControl grips. The package and all its components are top-quality. This is Motion Pro’s second generation of the kit. It’s simple to install and rugged. From grip to throttle body, I really like every component and feel they’re on par or better than stock.

The cables are top-notch with smaller housing (lined with slippery PTFE) diameters on the lower ends for increased clearance under your fuel tank and between your frame. The tops are robustly housed and feature very solid billet aluminum in-line cable adjusters. The cables lead into a snap-together throttle housing that is ultra-compact and secure. You can snap it together and the system stays put while you fumble for the bolts. That’s a nice touch. After the housing, the cables attach to the cams, in goes the Titan Throttle Tube and you’re done. It’s simple, sleek, heavy-duty and works great.

The power tuning of the system comes from the different sized Rev2 reels included in the kit. There are straight-rate 35mm, 40mm, 45mm and 50mm reels as well as the Off-Road progressive-rate cam reel. Each size up in the straight rate reel size reduces the amount of twist necessary to open the throttle body by about 10 degrees (each bike is different). So, if your stock reel measures 40mm and you want it to open faster, you’d put in a 45mm or 50mm. Want to twist the grip more to get to full throttle? Then go with the 35mm.

Thanks to Motion Pro’s website, I know my 500 EXC’s stock throttle reel is right around 36mm (I measured 35mm with a tape, but I trust them). So, for a straight replacement, the 35mm reel is close. If I wanted a faster opening throttle on a 500cc off-road bike, I’d put a 40mm or 45mm in. But I definitely don’t want that. Ideally, I’d love the big 500 to use its grunt as long as possible at low rpm. We’re talking massively controllable power right off idle. Then, if I’m sure I have all my crap together, I’d like it to blitz to about a million mph from half-throttle up. The Off-Road progressive reel does just that. The off-idle rate of the throttle pull is mellowed out (equivalent to 33mm or so); the pull follows just under stock until the last half, where it passes the stock reel’s pull and opens faster.

The result? The bike is more controllable at low speeds when picking my way through obstacles or doing anything technical. I get less fatigued in technical riding and enjoy the torque factory that it is. At the same time, the top end is just as alive and quicker-to-enjoy than stock thanks to the progressive ramp of the cam.

I can’t imagine needing the other reels for this bike, personally, even in a full race situation. The stock throttle opens wide at about 58 degrees rotation. I’ve raced this bike plenty with that and never thought to myself, “Man, I wish this was more aggressive.” The 50mm reel – the most aggressive – does this in 41 degrees. I don’t know if my arms could handle it.

Installation is super easy. Connecting the cables to the throttle body on my bike and adjusting the tension is the hardest part and that’s mostly an exercise in patience for me. If I didn’t have full hand-guards on my bike, swapping out the reels would take about a minute or so.

In all, it’s really cool to have a power-tunable part that doesn’t have to do with gas or electricity. The Motion Pro Rev2 Throttle Kit is analog. As such, I expect it to last a long time and not give me any fuss. After 500 miles of use, it’s still making me throttle happy.