Saturday, March 5, 2011

What To Do?

It's raining.
I really really wanted to get out on the road and test out that Garmin thingy.
Actually, it gave me a spot of trouble this morning as I was mounting the sending unit on the chain stay.
The Garmin sensor is one of those all in one doohickeys, central sensor and and arm thingy hanging off the side.
Same design as the Cateyeball units except the sensors are reversed.
On the Cateyeball, the arm is for the crank arm, the main unit for the wheel.
The Garmin reverses this, I'm guessing for patents or something.
Anyways, this posed a problem for the arm thingy is really really close to spoke magnet:



Because of this, I had to move the whole unit back on the chainstay to get the needed clearance.
This meant I had to move the crank arm magnet back also:



It's hard to tell from that image, but I had to offset the magnet for the center of the crank arm is grooved, or recessed so the magnet can't lay flat in the center.
This is fine and sort of dandy, but now, the cadence thingy is sort of at the max distance from the crank arm:



The thing is, I can't move it closer without having the wheel sensor hit the magnet on the other side!
Boy.
What to do?
I didn't want to do it, but I had to.
I moved the arm thingy so that it extends skywards(instead of downwards) in order to get a more, uh, favorable positioning for both sensors:



For comparison, here's the Cateyeball sensor next to the Garmin. You can see how the sensor arm positions are reversed:



They are about the same size height wise, I just don't like that wheel sensor sticking up like the arm on the Statue of Liberty.
I'm thinking of mounting it upside down, so that if the sensor arm moves inwards and comes into contact with the spokes, it will kick out instead of causing some catastrophic fail.
I mean I ran the Cateyeball sensor sort of the same way, on top, so I guess the chance of fail was the same, still, that set up makes me nervous.
Upside down may be the way to go.
The thing is, I don't know how I feel about that thing hanging down there below the chain stay.
Let me see how it goes the way it is.
Hopefully, those aren't Famous Last Words(FLWs).

3 comments:

John Romeo Alpha said...

Man, I don't know about that sensor, it does look kind of giraffe-y like that, doesn't it? I notice your pedals also need a TL-PD40 like mine when re-greasing time comes around! You could borrow mine, but the postage would cost more than the tool.

limom said...

A giraffe with blue legs!
I think when my pedals get all crunchy, I'll just use The Flat Tire Bottom Bracket Tool and a vise.
I actually thought about road shoes, for like five seconds.
Cheaper to just get new SPDs.

Steve A said...

In my experience, Cateye makes good computers and marginal lights. OTOH, my Garmin GPS is rock solid so I think you are in a "no lose" situation other than your pocketbook...