oik01

I bought a used garmin vector 3s.
When I calibrate it to my headunit, I found that after calibration it gives torque readings. They seem fine when the reading is present ( -0.03, + 0.05) but every 3 or 4 or 5 readings depending on the time I get "--" for a reading. Is it normal for that to be so frequent or am I getting disconnects. When i used it concomitantly with my trainer I got some lower numbers initially and had oocasional zero powers. I opened it and put the battery in again and re-calibrated everything and had numbers that overlapped with the trainer. However after the calibration I still had the "--" torque reading somewhat frequently. I am just wondering whether this is a bad sign and I will be getting the drop outs reported in forums down the line? I am asking because if this is normal behaviour I will keep the unit. If it is not, and usually you get actual readings far more frequently I will not...

Iride01 

I've no idea, but you do know that Garmin has their own user forums for their stuff don't you. You might get more answers faster from other users over there....... https://forums.garmin.com/sports-fit...ing/f/vector-3

Barry2 

Assuming you're using a Bike Computer... Try turning off Bluetooth on your phone.
My iPhone often causes havoc with BLE comm's.

Barry

oik01

It's on ant +

Barry2 

BLE is 2400-2483MHz
Ant+ is 2457MHz ...... right in the mix of BLE

It's cheap to try, why not give it a go?
or don't !

Barry

surak

Vector 3s had a notoriously bad battery cap issue causing dropouts that Garmin tried to fix, several times even. Maybe check that yours has the latest caps? If not, you'll want to figure out how to get the replacement caps.

oik01

Thanks. I am aware of the drop out issue and caps and this is the reason for the post... to know whether to get one from their website ( or more comforting return the item) and buy another powermeter.
I guess the question is: For anyone who has the same vector 3S powermeter working without any known accuracy or dropout issues: When you calibrate the powermeter do you only see numbers reported for torque or does it also show you that "--" reading?

surak

Gotcha, yeah unfortunately (well, fortunately for me maybe) I don't have experience with the Vector 3s because I was scared off by the issues and went with PowerTap P1 (aside: my right pedal crapped out and SRAM replaced them with P2 pedals for free, but now they've discontinued the line and I am somewhat concerned going forward). I have some regret of not holding out to get the Favero Assiomas instead, because I'd originally wanted them but went with the P1 pedals instead when they were on sale a few Cyber Mondays ago and cheapest of all the pedal options. If you didn't get a screaming good deal on your Vector 3s, maybe returning them and getting Assiomas would bring you peace of mind.

oik01

Perhaps. Actually 4iiii have some aggressive clearance sales on. But I don't think its fair for the seller that I return it if its functioning in normal condition. So just trying to figure out if the "--" torque reads are normal...

DaveLeeNC

I have Vector 3's that had dropout problems that were fixed with new doors from Garmin. When paired with my Bontrager 1030 (basically a Garmin 1030), after a successful calibration I see something like '2' or "-4", or "3", etc. It is a single # that does not change.

I also have another bike with older Vector 1's (originals) paired with a Garmin 520. after calibration I see #'s like 0.03, -.0.12, 0,5, etc. And the field is also labeled torque.

I am guessing that there are pedal firmware version variables that matter, different computer models that matter, and software versions in the computer that matter. When I went out to calibrate my Vector 3's I thought I could be helpful here. Maybe not.

dave

oik01

This is helpful. So you don't see "--" it sounds like? I might try the new doors it seems it worked for many

DaveLeeNC

I sometimes see "--" during calibration, but do not ever recall seeing one after calibration was complete. But once I got 'Calibration Successful' I moved on, so maybe there have been times. I definitely had dropout issues before I changed the doors. In fact I only have maybe a half dozen rides in since the door change. But no dropouts since then that I have seen, where before I had a bunch of them.

dave

oik01

Oh. I only see it in the calibration screen. Once I get calibration successful and it's showing torque. When I move on back to power it doesn't show

oik01

So I figured I would see if its accurate manually. Did a few quick intervals and measured them on the saris cycleops trainer and the powermeter. Interesting finding but kind of disappointing. The powermeter seems to underread by an average of 20 watts and really 30 watts during intervals. The more interesting thing is that often at the start of an interval there is close overlap but the vector 3s drift down compared to the trainer during that interval. I guess the problem is I won't be able to differentiate if this is left right imbalance vs inaccurate reads.

DaveLeeNC

oik01 FWIW, DC Rainmaker (www.dcrainmaker.com) has done a good bit of work WRT various power meter accuracy levels. It will take a bit of digging within his really extensive body of work to find it, however.

From what little I know about this stuff, I would not view the power #'s from a trainer as the 'power gold standard'. I would also observe that the power measured at the pedal would be expected to be a bit higher than the power measured further down the drive train (losses in the system - probably a few percentage points). Of course you are seeing the opposite in this case.

dave