road vs. TT bike on Trainer Road- power issues
So I have been in the process of working with my LBS testing out my bike fit for my TT bike and so I have swapped it onto my trainer in place of my road bike the last couple of weeks. I redid a power test on Trainer Road for the TT bike and came out with some significantly higher numbers. I understand that all numbers are relative to the bike, etc., but I did try to be consistent in resistance applied to back tire, tire pressure (granted different tire on each bike), etc. My watts were definitely higher for the test, but then they were even insanely higher when I went to do my OS FTP ride this week. I had re-set my FTP, etc. in TR and so everything should have been fine, but I was doing the ride, the power #s just seemed way too high, so I tried riding primarily on RPE, but my HR was much lower, and it definitely wasn't quite as hard as the previous FTP rides in recent weeks. And while I would love to believe I could put out over 300 watts for a one interval, let's be honest that I can't go from an FTP of 165 to 214 to 300+just by changing a bike and doing 5 weeks of OS.
My questions (other than what am I doing wrong here?) are:
1. Does everyone who rides more than 1 bike on a trainer do more than 1 test? If so, how do you manage that timeline of testing?
2. How can the watts/speed/etc. be so different? My previous FTP from the road bike test was 165. I have read many forum posts looking for an answer before I posted, so I can see that there is some consensus that speed/distance has no importance on a trainer. My cadence has increased, but that was relatively small compared to other indicators, like "speed" which increased about 50% over my road bike.
3. If watts continues to prove to be a moving target until I can afford a PM, is it better to work with RPE/HR?
If anyone could give insight into what is going wrong here, I am all ears. I had a tough time with tri-technology last week, and I loved having TR until I swapped bikes, so I am just confused and feeling discouraged. Thanks!
Comments
Susan, are these watts from a power meter or from TR? Make sure that all of your bike statistics are entered correctly (tire size, frame size) If you don't have a power meter, find someone with a cyclops wheel you can borrow and do a TR ride with that hooked up while recording on a garmin or Joule.
@Edwin- those are from TR. That's all I have right now. By Cycleops wheel do you mean one with a PT in it?
Yes. If you know anyone with a powertap wheel that is the same size as your bike, borrow that and do a test. It will let you know exactly what kind of power you are putting out. That is the real beauty of the Power tap, you can switch it to any bike. I have a quarq. It is in my crank. I can switch it from one bike to another, but it is a lot of work. The Power Tap is changing a wheel. Check your local tri-club and see if anyone will let you borrow one.
I had a recent issue with TR and emailed them. Their customer service got right back, so I would also email them your thread directly to see what their thoughts are.
I ride both bikes indoors using TR as well. However, I have the opposite effect. My road proves to be a higher FTP and my tri is consistently 10watts lower across the board. Less power, more aero on the road = still moving faster. As long as the numbers are consistent every time on TR doesn't really matter if FTP is 100 or 500. (IE: you'll be able to track your gains +/- )
I would ensure your speed/cadence sensor are lined up correctly. My ant+ was detecting the sensor, but the crank arm magnet wasn't close enough to the chainstay sensor. The chainstay sensor simply rotated just a little and then it wasn't working. My troubleshooting skills at 5am are no good, so I just road HR for that ride. Then a minor adjustment, and BOOM, all worked again. Make sure you sensor is good, battery good, all lined up and reset.
LET US KNOW HOW IT GOES!