Critique my PowerTap plan

Triathlon Forum
1

After much research, review, hmming and hawing, I think I’ve finally got a setup that would be ideal for my situation.

This will be used for both everyday training and racing (with a cover). I’m just under 200lb and the roads I ride are not the greatest. But, having said that, I’ve been using the stock Easton Vistas (24 spoke rear, 2x drive side) that came on my bike for 3+ seasons without even needing a trueing. So, I must not be too hard on wheels.

I currently use a Forerunner 305 on both the bike and run. I am completely happy with it, and it does everything I want with the exception of power. I like the customizable displays (up to 4 segments on a screen), the auto-lap features, the distance/time alerts and the interval workouts by both distance and time. I also have the HR strap and speed/candence sensor - both of which have been reliable.

So, here’s my plan…

Wheel: PowerTap Pro+ hub-only, Kinlin XR-300 rim 32-spoke, Sapim Race spokes, brass nipples. Total weight should be ~1153g.
Computer: Garmin Forerunner 310XT.

This should allow me to keep all of the features of the Forerunner 305 that I like/use, but also add in power. A few things I like about this setup are…

  1. I’ll finally have power!
  2. The wheel should be even more durable than the Vista it will replaces. And, it’ll only weigh ~133g less - mostly/all in the hub.
  3. I’ll be able to customize the displays to see specifically what I care about. This is a big advantage over the stock PowerTap computer.
  4. I’ll still have the auto-lap and alert features, which I use for both pacing & nutrition reminders.
  5. It will use GPS for speed/distance (as opposed to relying on the accuracy of a wheel circumference number).
  6. It will use a crank magnet/sensor for accurate real-time cadence (as opposed to an estimate from the hub). I mainly ride by cadence currently. So, this is a biggie.

My only real concern is the two units working together w/o data drops with the 310 installed on the extensions between my hands. But, it sounds like all of the reports of problems in this area have been with it paired to a Cinqo. So…

Any inputs/critiques welcome.

Thanks.

Steve

2

Sounds like a decent plan…for what it’s worth, the cadence estimate from the hub has been really accurate for me.

3

What is your cost going to be. I was thinking of getting a second PM and using my 705, but did not know how much the PT hub would cost me.

chris

4

dont put speed up on your main screen, just power+ cadence.

how about 28 spokes, ive heard the kinlins are plenty stiff.

5

Steve,
I forgot to add this to your previous thread about the wheel build…but, have you considered just having the PT wheel built into your current Vista rear wheel? I teammate of mine did just that last year by putting a wired SL hub into his Vista rear wheel. Looks and works “top notch”. The nice thing about that is you will still have a “matching” wheelset :slight_smile:

The only thing that would worry me about that plan is that its 24h. Which, although you say you seem to be “light” on your wheel, at your weight it might be less robust than a higher spoke count build. That said, deep rims can “handle” less spokes for an equivalent wheel strength.

310XT sounds like a good plan…but, I don’t know if I’ve heard of anyone using it with a PT yet. Don’t forget to check out the ANT+ head units from Specialized and the new Garmin 500 (although it doesn’t have the “workouts” function).

6

My thought was to use the Eastons as well. My question still stands as to how much the hub alone costs?

chris

7

You can get MSRP prices for the various hubs off www.wheelbuilder.com .

Steve

8

dont put speed up on your main screen, just power+ cadence.

how about 28 spokes, ive heard the kinlins are plenty stiff.

I rarely look at speed. It’s not even one of the 4 data fields on my Forerunner.

I considered that. But, since it would only save a whopping 28g, I might as well go with the extra durability.

Steve

9

Steve,
I forgot to add this to your previous thread about the wheel build…but, have you considered just having the PT wheel built into your current Vista rear wheel? I teammate of mine did just that last year by putting a wired SL hub into his Vista rear wheel. Looks and works “top notch”. The nice thing about that is you will still have a “matching” wheelset :slight_smile:

The only thing that would worry me about that plan is that its 24h. Which, although you say you seem to be “light” on your wheel, at your weight it might be less robust than a higher spoke count build. That said, deep rims can “handle” less spokes for an equivalent wheel strength.

310XT sounds like a good plan…but, I don’t know if I’ve heard of anyone using it with a PT yet. Don’t forget to check out the ANT+ head units from Specialized and the new Garmin 500 (although it doesn’t have the “workouts” function).

I had not thought of that. But, to be honest, the cost of the rim/spokes is so small in relation to the cost of the hub… I’d probably also have to pay a building fee if I went that route, which I won’t if I go with the entire wheel. Might as well just keep the Vista as a backup.

And, I agree. While I haven’t had any trouble with the 24h Vista, I’d just as soon have something more durable, as long as it’s not a complete pig.

Steve

10

sounds like a good plan to me. I have been using the 310 as my main power puter for about a couple of months and am happy with it. I compared the readings on them for a while but then stopped bothering. The only difference is that there is about a second or two lag with the 310 over the pt computer, certainly not a big deal.

No issues with it dropping out at all. That must be a Cinco thing only.

I also have vista’s with a bunch of miles and they are pretty tough IMO. I hear you about just getting a new wheel though as it will not cost much more than having it rebuilt and will be, well, new. FWIW I have about 4k worth of training/racing mileage on an 808 clincher and have been happy with just using the one wheel. If I were to do it again I would likely have just built a solid training hoop and raced with the cover but it just seemed wrong to me not to race with zipps :wink:

11

Thanks for the input on using a 310/PT combo. Nice to know that it’s working for you.

Just out of curiosity… What do you have up on your main bike display?

Right now, with my 305, I have Distance, Time, HR and Cadence. I’m torn whether to put Watts in place of Distance or Time with the new setup.

Steve

12

Watts and heart rate. All I care about when racing. On the other screens I have lots of stuff.

13

Can anyone confirm that the Garmin units (mine is the 705 specifically) will automatically use the GSC-10 sensor’s cadence reading rather than the PowerTap’s when available?

I would love to be able to pull my GSC-10 sensors off when racing certain courses…it may only be a couple of watts, but every little bit helps. I would only do that for courses without satellite obstructions.

Thanks,
Chris

14

Are you going to mount the 310 or wear on wrist? There was a thread somewhere that some people were having difficulty with the 310 worn on wrist and with either the Quarq or Powertap or both. Think it was a problem with one wrist but not the other.

Curious where you are buying the PowerTap from. I sent you a PM last week with where I purchased mine.

I am really torn between a 310 with bike mount or a 705 as a head unit for my new Quarq. I already have a 305 that I love and use for running. Curious why you choose the 310 over the 705 when you already have a 305.

15

I’ll get the quick release kit, and mount it on my bike (just like I do with my FR305).

I know the thread(s) you’re referring to. They were all with the Cinquo. I haven’t seen anything about the 310/PT combo having problems, including a post a few up from this one.

I’m going with the 310 over the 705 for a couple of reasons. The main ones are that it’s a fair amount less expensive, it will allow me to have all of my data in one place (Although, I don’t plan to even swim with the 310. It’s just not worth the risk. I can get my swim time after the race.) and that I can sell my 305 to make up for some of the cost.

I thought in another thread you said you already owned a 705???

Steve

16

Steve,
I forgot to add this to your previous thread about the wheel build…but, have you considered just having the PT wheel built into your current Vista rear wheel? I teammate of mine did just that last year by putting a wired SL hub into his Vista rear wheel. Looks and works “top notch”. The nice thing about that is you will still have a “matching” wheelset :slight_smile:

The only thing that would worry me about that plan is that its 24h. Which, although you say you seem to be “light” on your wheel, at your weight it might be less robust than a higher spoke count build. That said, deep rims can “handle” less spokes for an equivalent wheel strength.

310XT sounds like a good plan…but, I don’t know if I’ve heard of anyone using it with a PT yet. Don’t forget to check out the ANT+ head units from Specialized and the new Garmin 500 (although it doesn’t have the “workouts” function).

I spoke with wheelbuilder again.

They originally recommended the 32h Kinlin XR-300 because I was considering the PowerTap COMP (which only comes in 32h), and said the DT RR1.2 would be overkill for my situation.

Now that I’m looking at wireless (and not limited to 32h), they are recommending either the 28h XR-300 or a 24h RR1.2.

The RR1.2 rim is 119g heavier. And, even with four fewer spokes, the overall wheel will be 101g heavier. Not a huge amount. But, all rotational - especially the rim. So, I’m leaning toward the 28h XR-300.

Thoughts?

Steve

17

Steve,
I forgot to add this to your previous thread about the wheel build…but, have you considered just having the PT wheel built into your current Vista rear wheel? I teammate of mine did just that last year by putting a wired SL hub into his Vista rear wheel. Looks and works “top notch”. The nice thing about that is you will still have a “matching” wheelset :slight_smile:

The only thing that would worry me about that plan is that its 24h. Which, although you say you seem to be “light” on your wheel, at your weight it might be less robust than a higher spoke count build. That said, deep rims can “handle” less spokes for an equivalent wheel strength.

310XT sounds like a good plan…but, I don’t know if I’ve heard of anyone using it with a PT yet. Don’t forget to check out the ANT+ head units from Specialized and the new Garmin 500 (although it doesn’t have the “workouts” function).

I spoke with wheelbuilder again.

They originally recommended the 32h Kinlin XR-300 because I was considering the PowerTap COMP (which only comes in 32h), and said the DT RR1.2 would be overkill for my situation.

Now that I’m looking at wireless (and not limited to 32h), they are recommending either the 28h XR-300 or a 24h RR1.2.

The RR1.2 rim is 119g heavier. And, even with four fewer spokes, the overall wheel will be 101g heavier. Not a huge amount. But, all rotational - especially the rim. So, I’m leaning toward the 28h XR-300.

Thoughts?

Steve

If you’re going to go to a heavier rim, I think I’d go with a Velocity Deep-V over the DT rim.

That said, I think the the 28H XR-300 is a great choice.

BTW, that amount of rotational inertia difference is literally MINUSCULE compared to your body’s translational inertia…that shouldn’t even come into the conversation.

18

Thanks, again, Tom.

They also suggested that I consider the PowerTap Elite+ hub over the Pro+, since I am on the heavy side. Their reasoning was that they usually suggest swapping the aluminum axle in the Pro+ to steel (which the Elite+ comes with) to minimize flex and save the bearings excessive wear.

The Elite+ also comes with a steel freehub body (compared to the aluminum body on the Pro+), which may be better, too. I’ve seen a couple of wheels where the flat cassette cogs cut into an aluminum body. I’d like to not have that happen.

The Elite+ hub is 158g heavier. But, it’s (obviously) all at the hub. It’s $100 less expensive, too.

Wise choice?

Steve

19

No I own a forerunner 305 and a Edge 305. Plan on using a 705 with the Quarq but have not pulled the trigger. I have found there is a $100 difference between the two. I like the bigger screen with the 705. I won’t use the maps. I would also have to buy the bike mount kit with the 310.

One plus with the 310 is having a backup to the 305. Today if my 305 breaks I am SOL. I really use the 305 a lot.

20

Thanks, again, Tom.

They also suggested that I consider the PowerTap Elite+ hub over the Pro+, since I am on the heavy side. Their reasoning was that they usually suggest swapping the aluminum axle in the Pro+ to steel (which the Elite+ comes with) to minimize flex and save the bearings excessive wear.

The Elite+ also comes with a steel freehub body (compared to the aluminum body on the Pro+), which may be better, too. I’ve seen a couple of wheels where the flat cassette cogs cut into an aluminum body. I’d like to not have that happen.

The Elite+ hub is 158g heavier. But, it’s (obviously) all at the hub. It’s $100 less expensive, too.

Wise choice?

Steve

Sounds wise to me…the only “gotcha” about the Elite+ wheel system (IIRC) is the fact that the head unit that comes with it doesn’t have all of the display smoothing options as the higher end models. But, since you’re not getting that anyway, it sounds like a good idea to me :slight_smile: