Rode our Hills R Your Friends ride on Saturday. 74 miles with 9650 feet of climbing, ouch. Crosses the Laurel Ridge 4 times. Got serious cramps on the third climb but drug myself to the finish.

Anyway on to the question. Got home and checked the bike computer. Said my max HR during the ride was 212! Normally never get much above 160 which is where I have my red zone set. Spent 45 min above 160 during the ride. I have registered in the high 180's at times but never above 200.

So is this possible or a computer malfunction?

Probably an anomaly. Had a friend 45 how had a max of 265 on a ride. Turns out it was some sort of static interference with his jersey.

On a different front, I've had 500' of elevation change recorded on my Garmin 305 while riding on a flat road when a cold front passed, and had max MPH spikes (60 mph - I wish) for no known reason.

Fact is there are factors that can influence any measurement and throw it off.

I would think that it almost has to be a measurement problem. I once did an average speed of 115 mph on a C ride. We must have had to slow down for the STOP signs. Electronic apparatus can work great but when it malfunctions, it can be way off.

On my polar, I get readings that are double my actual heart rate at times. You could have been running something like 106 at one time and had it read 212.

I have hit as high as 196 but that took eye popping effort. Anything over 170 takes are real hard push. So I would think that if you had pushed hard enough to get that reading, you would know it because your tongue would be catching in the spokes of your front wheel.

There is a spot on one of my regular loops where my HRM always shows 212.

Turns out that there is a telephone switch box near there and there must be interference.

Not uncommon.

Ride under any power lines???

Same here...I get a 212 spike if I go down a road with high power lines.

Power lines and even traffic lights can affect a monitor- but the most common cause for me was riding in close proximity to another rider that also used a heart monitor. Cross- readings will occur on some of the older Polar models and cheaper units. We had the problem on the Tandem as both of us used Polar units. Even with the higher priced models where cross interference is not supposed to occur- we had to ride with one strap on at a time between us. It was good for me as if I was wearing the strap- my pilot could tell when I was about to cry enough- so he always rode within my limits- just.

I changed to a garmin and never had the HR register problems- But Elevation spikes and speed spikes occur occasionally. Normally near power lines.

Should have added on the original post. On climb #2 I did note a HR reading of 189. I was mostly wondering if the cramping thing would cause your HR to really shoot up? Well aware of the possibility of cross talk with other computers and outside interference.

And yes, the efforts on this ride are prone to have your tongue come close to getting tangled in the spokes. Climb #2 has a 21% section and and end of climb #3 is steeper. Sometimes you have to ask yourself, who built these roads and for what purpose. This is the 9th year of this ride. Last year was the only year all starters finished.

So the reading is most likely some kind of interference but not out of the realm of possibility.

I was on a cross country tour on my KLR 650 motorcycle (1 cylinder) and my Garmin showed a max speed of 105 mph. Very difficult on this small bike and almost impossible as loaded as the bike was. I recreated it by tossing my stuff onto a motel bed from across the room..it must have hit that speed during the throw...my guess anyway.

Mike

What causes it for me is if my jersey flaps against the strap before I've sweat enough for really good skin contact.