New Sprockets and Masts for Mirage Drive

Hi Yak,

Great installation tips! If the new masts and sprockets pass your muster, the days of the old stainless sprockets are severely numbered!

I noticed that the Locktite can set up pretty quickly, especially with the heat of friction -- threading each mast immediately after application is easiest.

Once you press the chain on, that master cog holds it in place during installation very nicely. For the first several hours of operation though, the popping of the chain in and out at the end of each stroke on the new sprockets can be annoying. Eventually the chain and cog mate and the popping diminishes.

I think you're going to really like the crisp feeling from the Drive during your sprints!

Roadrunner

The tight mast to brass insert fit was not what I was expecting. My initial thought was to screw in the mast to the sprocket without any loctite to check for fit & depth.

Figured to just hand tighten it. Surprised to find the threaded mast end has to cut its own threads on the brass shoulder. This could fool a self-installer into thinking that the parts are wrong, or make a mistake and not screw in the mast deep enough.

Ya, I did work quickly with the loctite and vise-gripped the mast all the way in. I also screwed them in only once - no dry run.

I am not implying any Hobie parts defect, on the contrary I believe the very tight fit will mean in no way will these masts come unscrewed by themselves or wobble any. I am almost afraid that, once installed, that unscrewing the mast will cause the brass insert to break free of the plastic and spin. No big deal as I don't change fin or mast sizes once turbos are installed.

I also replaced the old sprocket guards and small outhaul leech that was used on the Stainless Steel sprocketed drives (circa 2002). The Outhaul block (81050001) and Fwd Sprocket guard w/ screw (81055001) provide a more finished look while being smoother and more streamlined.

The brass is threaded. The mast is not supposed to cut its own threads, so maybe cross threaded?

_________________
Matt Miller
Former - Director of Parts and Accessory Sales
Warranty and Technical Support
Hobie Cat USA
(Retired 11/7/2022)

Only the bottom part of the insert is threaded, the top 5/8" is unthreaded and I am calling this the shoulder. One would think that the mast would slip into the brass insert shoulder to find the first threads, but instead you must twist in the mast and allow it to cut its own threads until it gets to the threaded section. The amount of self-cutting is minimal, but there is no way one could use a screwdriver to install these. The self-cutting produced visible lines/grooves and scratching on a 3rd V2 sprocket that I experimented on. (Maybe "cutting its own threads" is not 100% accurate description, but it was not a slip-in fit either) Maybe one could use a hammer to tap in the mast, but the brass is soft enough to allow the mast to bore its way in.

With the course thread, and the depth measured, and the fact that both fit the exactly same was I am certain they are not cross threaded.

If the mast is 5/16" OD and the insert is exactly 5/16" ID then when the theads are cut on the mast it may make a perfectly tight fit slightly tighter. The "raised ridges" created as the mast is machined & tooled with threads are almost certainly what I am seeing.

Understand that I am pleased with the installation and am confident that it is done correctly. The heads up is in case others run into the same issue not to fret.

As, with any self-install I wanted to be sure users were paying attention to some possible issues.

Matt, no worries, there is no need to design a another new sprocket

Odd. Yes the shoulder is not threaded, but I have been able to drop the threaded portion of the mast through the shoulder... as designed. Something is different.

I assume the mast threads are more prominent for some reason.

_________________
Matt Miller
Former - Director of Parts and Accessory Sales
Warranty and Technical Support
Hobie Cat USA
(Retired 11/7/2022)

Hi RR, Clipless pedals and solid crank arms have held up to my friend "Kilowatt Jack's" massive sprints. (The old pin lock holds didn't, but that's been rectified.)

Once you get used to riding a bike with clipless pedals you can never go back to regular pedals. I feel the same way about Mirage Drives.

A major advantage to stock pedals is that you don't have to hold your feet up on the pedals. It's good to have your feet attached to the pedals on the back stroke.

ONWARD!
Mack