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Doc, I saw in HEAVY DUTY issue #125 that you had a Cruise-Mate throttle lock installed.

I love the idea and have used something similar before on my 2003 and 2010 FXST. When I bought my current bike, a 2011 Deluxe, it didn’t have the thumb wheel installed. I raised this with my mechanic at a local Harley-Davidson dealer and asked them to put a thumb wheel in and asked them about the Cruise-Mate.

The guys at the dealership were shocked that I would consider it but being mechanically illiterate, I asked for a simple explanation.

I was told that the wheel was an adjustment that should only be used by mechanics at service to set throttle tension. This is because if the bike is turned full lock either way with the wrong adjustment, the throttle will not release and could caused a serious safety issue. This sounded reasonable to me.

What is the go with the thumb wheel and the throttle-lock devices? Are there any issues or anything else I should be aware of?

– Andrew

Hi Andrew and thanks for your enquiry. Firstly, people have been using the Harley-Davidson thumbscrew as a makeshift cruise control for many years – not that I am in any way endorsing it for that use, though everyone I know has always done it, including me.

If it is set so that the friction is just enough to hold the throttle in position, but not too much so that the throttle can easily be rolled off, it should be no more dangerous to use that a proper cruise control system, which, by the way, also needs some rider input to cancel, whether that be rolling off the throttle or hitting the brakes.

Now Harley-Davidson is a big, fat company and has been the target of many lawsuits over the decades and it is therefore super defensive and trains its employees to be that way too, hence the apparent horror at your question at the dealer.You’ll notice your owner’s manual is full of warnings about serious injury or death.

Now the Cruise-Mate can be set to where just a light flick of the switch cancels it and, like the thumb screw, it can be set so that the throttle can be readily rolled off or on again should the situation require it.

For what I would assume to be an attempt at preventing lawsuits, and despite listing itself all over its website at as a “motorcycle throttle cruise assist” – in other words a mechanical “cruise control” – in its operating instructions it states in bold red lettering that “Cruise-Mate is intended for motorcycle warm-up and service only. Under no condition do we recommend locking the throttle open or removing your hands from the handlebar while the motorcycle is moving.”

Now the thing you were told about turning the bike to full lock either way causing the throttle not to release and cause a serious safety issue strikes me as a bit irrelevant, as this is not something you would ever do when riding along. Or if you did, you’d be in trouble anyway – with or without any kind of throttle-setting device.

I would not have fitted one to my wife Jane’s Dyna or my brother-in-law’s Sportster if I thought there was any real danger. Nevertheless, operating a motorcycle under any circumstances is potentially dangerous and should be done with a good dose of commonsense and caution.

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