Setting up a Kickr Snap

[AlanW]

I used my new Kickr Snap trainer for the first time last night, while the ride is very, very realistic the fluctuation in the wattage figures is rather alarming, so I'm something isn't right? My Tacx Vortex didn't do it, nether did my Kirt Kinetic Rock n Roll trainer.

On the flat maintaining the same speed and the same cadence yet the wattage is fluctuating 20 or 30 watts all the time?
I did have the wattage response time set to "instant" in Zwift, but even altering it to "3 second delay" its still all over the place?
Then just to add to my woes, when I came to a climb, I dam near came to a stand still as my speed dropped down to 2mph. In fact at one point I thought that the virtual me was going to get off and push! It also seemed to slow increase the resistance, so it only started to kick in after 5 degrees I think?
I did the spin down test first using the Wahoo app, then shut the app down and turned off the Bluetooth, then opened up Zwift and connected everything via Ant+. But my understanding is that only one app can control the trainer at a time, so what's the point in doing the spin down test with the Wahoo app, only to shut it down??
The Ant+ dongle is on a 1.5 metre USB extension cable, which sites it directly under the trainer. So I'm pretty certain that's not the problem.
As I understand it, which makes sense I guess, but you cannot have two applications controlling the trainer, ie Zwift and the Wahoo app.
If I have read the stuff on the net correct, to start the ball rolling you open up the Wahoo Utility app, turn on the Bluetooth and connect your phone via the app to the trainer. You then pair the trainer, the speed sensor and your heart rate monitor to the app. At this point it will advise you if you need to do a firmware update or not. In my case, it had the latest firm date.
From here, you carry out a spin down test as per the instructions on the app. Advanced spin down first when you first connect the trainer, then standard spin downs thereafter. Now according to Wahoo, the ideal spin down time is between 12 and 15 seconds. Adjust the tyre accordingly and retest if required. Once that's completed, shut down the Wahoo app and turn off the Bluetooth.
Now open up Zwift and pair everything via Ant+ and then off you go. How easy can it be......and while yes it loads the resistance up, its seems very extreme on occasions to the point that it brought me to a standstill last night!! Reading other peoples thoughts on the Zwift Q&A page, they mention ERG and SIM mode in the Wahoo app and how this can effect it. But I don't get that coz the Wahoo is shut down so how can it still interface with the trainer??
Which then make me question, if you do the spin down with the Wahoo, how can that effect what happens in Zwift as the two are not connected? I get the spin down test if you intend to utilize the Wahoo app to train with, but to do it and then shut it all down, doesn't seem to make sense. Perhaps I'm missing something??

 

[AlanW]

Well despite the best efforts of Melinda at Wahoo, the erratic wattage reading remain and the effort that I have to apply when ascending just doesn’t seem right to me? But I encountered new “problem” last night and I don’t know if it’s all related or if anyone can offer any further advice?

So I decided to do structured workout on Zwift last night, the first ten minutes was a warm up session and you had to maintain a steady 140 watts. But less than a minute into the session and the resistance ramped up that much it stopped me dead and I was unable to turn the pedals? It then popped up with a message, something like “ERG mode was disabled”?

Needless to say I aborted that idea so then decided to do part of the Prudential Ride London route instead. Set off and quite quickly managed to locate a fairly decent sized group to ride with. This was ideal as at least now I can monitor my efforts against others as we climbed up Box Hill. Thankfully the group I was riding with wasn’t a “flat out” group and despite having to put what I considered to be excessive effort I stayed with the group right to the top. On the decent the same story, stayed with the group and all was going well. Now if you ride this course you will know that after descending Box Hill eventually you go into a sort of deserted underground tube network, and this takes you very neatly back into the city. However, in order to get back up to street level you have to go up a short sharp ramp and according to Zwift this ramp is rated at 15%. But just as I hit the bottom of the ramp, the resistance kicked in so much that I had to change down to my bottom gear as quickly as I could and literally heave the pedals over, the rear tyre whist not slipping was really struggling to maintain its grip. Meanwhile, I just watched the group disappear up and over the top never to be seen again??

Any ideas!

 

[bobinski]

Alan,
I cannot address your issues but on a Bkool pro that transition in the tunnel to 15% is abrupt and brutal and I think realistic. I am happy if I hit 8kmh up it. Much like the 14% on Watopia and similar gradients in Bkool rides.

Re the other issues there are a lot of snap users on the Zwift Facebook uk users page so perhaps ask there.
https://www.facebook.com/groups/zwiftriders/

 

[AlanW]

I'm a FB member already, I'll check it out, thanks

 

[Winnershsaint]

Here's my take on erratic wattage on the Kickr Snap. Rode three laps of the Richmond flat route yesterday. One segment that comes up on Strava is known as 10m TT. which I did in 29 mins 52secs. Strava stated an average power for the segment taken from the Kickr Snap of 154W. Using a simple bike calculator tool such as this http://www.bikecalculator.com/ a significantly different power reading of 216W for 10 miles over 0% gradient for an 84kg rider. That's a huge difference. I am prepared to accept the dumb trainer with a known power curve that is supported by Zwift that I have used in the past may have over estimated my speed and time over the segment, but the zPower estimate given for it is in a similar range to that of the calculator figure rather than the Kickr Snap.

I suppose completing an FTP test would go some way to establishing what my FTP power actually is but I very much doubt if it will be an accurate reflection. The point is that both AlanW and I have purchased this smart trainer on the basis that gives an power accuracy of + or - 5%, and I don't think we are getting anything like that and as such it doesn't do what it says it will do and is therefore not really fit for purpose.

 

[AlanW]

Good point and well made. I am at the point that for the last 10 days I have been sending my ride files to Melinda at Wahoo for them to maybe come up with a solution or even an explanation. Well last night I decided that enough was enough and it has just this minute been returned to Wiggle for a refund. In the meantime I have now purchased a Tacx Neo from Halfords (please don't laugh, as I got a great deal!!) so fingers crossed Zwift should take on a whole new dimension this evening.

Oh, I have done a couple of FTP tests, near enough the same each time on or around an FTP of 276 watts, made no difference to the erratic wattage readings though.

 

[Winnershsaint]

Oh, I have done a couple of FTP tests, near enough the same each time on or around an FTP of 276 watts, made no difference to the erratic wattage readings though.

276W is considerably better than I'm achieving and although the power readings are not necessarily going up and down anything like yours, I struggle to get anywhere near 200W at any point on a ride. I think that is low for the reasons outlined in my post above. Convert my efforts into W/kg and I am not even getting the power readings expected for a novice male untrained cyclist of 2.2W/Kg. Now I accept it is easy to overestimate one's cycling prowess but the figures from the Snap just seem ridiculous. I think I will open up a dialogue with Wahoo also with a view to getting this back to Wiggle. It's a shame I like the feel of the Kickr Snap and think it gives as realistic a ride as is possible for a wheel on trainer it's just I cannot trust what the data is saying. Although I don't have power meter on any of my bikes I have plenty of evidence to suggest that I am capable of exceeding 2.2W/Kg.

 

[AlanW]

276W is considerably better than I'm achieving and although the power readings are not necessarily going up and down anything like yours, I struggle to get anywhere near 200W at any point on a ride. I think that is low for the reasons outlined in my post above. Convert my efforts into W/kg and I am not even getting the power readings expected for a novice male untrained cyclist of 2.2W/Kg. Now I accept it is easy to overestimate one's cycling prowess but the figures from the Snap just seem ridiculous. I think I will open up a dialogue with Wahoo also with a view to getting this back to Wiggle. It's a shame I like the feel of the Kickr Snap and think it gives as realistic a ride as is possible for a wheel on trainer it's just I cannot trust what the data is saying. Although I don't have power meter on any of my bikes I have plenty of evidence to suggest that I am capable of exceeding 2.2W/Kg.

As you say first and foremost, raise a ticket with Wahoo, but mail Wiggle at the same time so that they are aware of the problems you are having. When I first had mine I did a couple of hard sprints efforts and the best I could manage was 432 watts, which is no where near a true reflection of my output. That said, "something" clearly changed as the last couple of times I have been hitting 700+ on a sprint effort, which is nearer the truth but still a couple of hundred out where I know I can hit on a Watt bike? It will be interesting to see what the Tacx Neo makes me?

 

[Winnershsaint]

Contacted Wiggle. Awaiting reponse

It will be interesting to see what the Tacx Neo makes me?

Quite a bit poorer springs to mind! My turbo bike is six year old Cube Peloton with a 50-39-30 triple 9 speed Tiagra drive chain. Direct drive not an option unless I'm prepared to bugger about. which I'm not!

 

[Winnershsaint]

Did a short session on Friday which involved trying the Kickr Snap plugged in but not controlled. According to wahoo this automatically defaults to Level 2 resistance which I could feel. After 10 mins of that I tried an advanced spindown, which I hadn't done before. I then intended to ride so I performed a normal spindown before going on the PRL course on Zwift. Power readings seemed more in line with what I'd expect. Only went as far as first part of Box Hill but power was increasing to around 3W/Kg as I climbed. Fingers crossed that this calibration session means that it behaves itself today.