Anyone compare 2 Cateye computers at once?

[kwayde1]

I bought a cc-mc100w wireless for outdoor use. I then purchased a Strada wireless to put on my rear wheel while on the trainer. They seemed to work fine. I was using Strava to keep track of my rides, but couldn't sync it to my notebook, so I went to MapMyRide which syncs fine, and I like it more.
So to the problem...when I started with MapMyRide, I took both Cateye computers along to compare them to the MapMyRide app. I went a short distance, then back home. The MapMyRide said I went .7 miles. I'm believing they are correct because I compared it to Strava the day before and had the same measurement. But the cateyes were both way off. The mc100w wireless said I rode .55 miles, and the Strada wireless said I rode 1.01 miles. I have checked and checked and reset and reset the computers to be sure they are both setup correctly. Has anybody else found their readings to be constantly way off the mark? I would like to find a computer that I can use on my trainer without worrying about the readouts being faulty.

 

[Globalti]

Hi, welcome. I see you are in South Michigan. My brother lives in Ann Arbor where he engineers motor car transmissions. He was the project engineer who foisted Hummer 2 on the world, to my mixed pride and embarrassment!

Can't help you with the computer problem though. Are you sure you're not going through a different space-time continuum whenever you ride your bike?

 

[biking_fox]

Different magnets set-up on different wheels, so some rotations aren't being counted? And others double counted? TBH I'd expect the GPS tracking on the app to be least accurate as it's most likely to suffer from signal drop-out, but that may depend on your route/area.

Really triple check that you've got the correct wheel dimensions inputed to the computers.

But I suspect sensitivity of the magnetic sensor and/or magnet position will be significant.

 

[kwayde1]

Hi, welcome. I see you are in South Michigan. My brother lives in Ann Arbor where he engineers motor car transmissions. He was the project engineer who foisted Hummer 2 on the world, to my mixed pride and embarrassment!

Can't help you with the computer problem though. Are you sure you're not going through a different space-time continuum whenever you ride your bike?

Since the Strada is on the rear wheel and has higher milage, I must be torquing so hard I'm constantly spinning out!

 

[kwayde1]

Different magnets set-up on different wheels, so some rotations aren't being counted? And others double counted? TBH I'd expect the GPS tracking on the app to be least accurate as it's most likely to suffer from signal drop-out, but that may depend on your route/area.

Really triple check that you've got the correct wheel dimensions inputed to the computers.

But I suspect sensitivity of the magnetic sensor and/or magnet position will be significant.

The tire size has been more than triple checked. I'll look at the magnets next. Maybe switch them around to see what happens.

 

[Globalti]

Wait a minute.... you've got two wireless computers on the same bike? How do you know they aren't interfering with each other?

 

[Smokin Joe]

Wait a minute.... you've got two wireless computers on the same bike? How do you know they aren't interfering with each other?

I hope you don't mean sexually?

 

[slowmotion]

I've put two bikes, each with a Strada, within 18" of each other, and the transmitter from one does indeed send signals to the adjacent bike. As regards accuracy, they are pretty good. I measured the distance between the start and end of my urban commute using a large scale mapping program, and compared it to the Cateye reading. The difference was fifty metres over five and a half miles.

 

[snorri]

The tire size has been more than triple checked.

Tyre pressure will also affect accuracy.

 

[Globalti]

Switching the magnets will make no difference; all they do is actuate a reed switch, which is either open or closed. Your problem is between the senders and the receivers.

 

[kwayde1]

I rode 1.13 miles according to MapMyRide. The mc100w on the front said I rode .86 miles. The Strada on the rear said I rode 1.72 miles. The rear seems to be picking up the front's number, hence the doubled result. When I started out, I rode .51 miles (according to the front mc100w), then turned around back to my starting point. I only gained .35 miles on the return trip where I should have gained .51. Maybe they are messing each other up. I'll have to look into this...


Since I posted the above, I found the rear computer was picking up both sensors. I moved the front sensor to the front of the fork. I instructions say to put it on the rear of the fork. Now they only pick up their own sensors. I also checked my tire pressure and they are very close to one another. Took a short ride, front sensor says .58 miles, rear says .74 miles. I'll have to wait to take a longer ride to see how they compare. Maybe the magnet strength has something to do with it. I ordered 2 new ones.

 

[snorri]

. I'll have to look into this...

On a tour in the Netherlands I was a little bored on a 30Km straight road (Afsluitdijk) but noticed little markers at the side of the road at 100 metre spacing. There was nothing much else to do but pedal and check the accuracy of my 'puter.

 

[Shut Up Legs]

On a tour in the Netherlands I was a little bored on a 30Km straight road (Afsluitdijk) but noticed little markers at the side of the road at 100 metre spacing. There was nothing much else to do but pedal and check the accuracy of my 'puter.

How did you check the accuracy of the markers?

 

[Globalti]

We had the same problem climbing the Dutch Alps.

 

[snorri]

How did you check the accuracy of the markers?

I chanced it.