PowerPod v3 Mounting Holes Question

[andyjw]

Hi,

I recently took the plunge and purchased a PowerPod v3. I've done an O&B calibration and a couple of shortish rides so far, and the numbers look pretty reasonable to me, based on what I see on my static trainer. So far so good.

The reason I'm posting is to ask about the holes used to mount the PowerPod. The mounting bolt supplied did not fit through these holes out of the box, so when I first mounted the unit the bolt effectively had to act as a tap, boring a thread through the plastic of the tabs on the PP body. This made it extremely hard work to mount. In fact I resorted to a bolt of the same size and pitch so that I could use a hex key and get more leverage.

I removed the unit from my bike before cleaning it yesterday and I noticed that some of the plastic around the mounting holes has flaked away, presumably due of the stress of being bored thorough. Refitting the PP was difficult again.

My question is simply...is this normal?! I'm worried that the mounting attachment won't last long as I intend to swap the PP between a few different bikes - that being one of it's major selling points.

Thanks in advance!

[Velocomp]

If the PP holes aren't lined up precisely with the corresponding mount holes, then it's possible you might see your plastic tabs show some sign of being "tapped" by the screw.

When the plastic tabs are inserted into the metal mount some level of scratching is inevitable. However, I am not aware of any flaking away of the plastic. If you could show some images that would be helpful.

[andyjw]

Thanks for the reply.

It's not what you've suggested as the bolt wouldn't go through the holes in the PP before I even introduced the mount into the equation. The holes were too small.

I considered opening them up with a drill but I decided it was too risky.

I'll try to get some images tomorrow.

[Velocomp]

Thanks for the reply.

It's not what you've suggested as the bolt wouldn't go through the holes in the PP before I even introduced the mount into the equation. The holes were too small.

I considered opening them up with a drill but I decided it was too risky.

I'll try to get some images tomorrow.

I have not seen this problem with any unit we have ever produced. One thing to be aware of is that, if the tab holes are not precisely lined up with the holes in the mount, there could be an alignment issue similar to the thing you are describing.

[andyjw]

Hi,

I've attached a couple of images as requested. In one I've tried to show the groves in the mounting holes cut by the mounting bolt. In the other I've tried to show where some of the plastic around the mounting holes has flaked away. (Not the best photos I'm afraid. It's hard to get the phone to focus on totally black detail.)

IMG_4153.jpg (76.82 KiB) Viewed 6748 times

IMG_4154.jpg (44.42 KiB) Viewed 6748 times

I fully appreciate your position. You've manufactured hundreds / thousands of these units and I may be the first person asking this question. Plus I've run the bolt through it now, so I can't prove that it didn't slide through unimpeded straight out of the box. I'm asking you to trust me, it didn't!

I don't think there's anything can be done for now anyway. As I said, I plan to move this between a number of bikes, utilising the GoPro mounts I already had for hanging lights under my Garmin in the winter. I'll keep an eye on the wear this causes and report back if it worsens.

One thing I have noticed is that the central 'prong' (for want of a better description) of the mount you provide with the PP is chamfered. None of my GoPro mounts, or any I've looked at online, have the same. The chamfering makes it much easier to align everything.

[Velocomp]

Please keep an eye on this, and let me know if you see things get worse.

[andyjw]

Hi,

Following up on this thread with more mounting issues.

I have been in contact with Tom to check my calibration files. He spotted some wobble in the ride files I submitted and asked if I was using a plastic mount. I was - I use Garmin out-front aero mounts - and we concluded that was the cause. Time to look for a metal mount...

After some research I decided to take the plunge and purchase a k-edge combo mount. I'm hanging some pricey kit of this thing so I wanted something trustworthy and the consensus online seems to be that k-edge are the best, albeit expensive. (More on which later.)

I attached the k-edge to my bike fine, but then discovered that the PP does not fit in the GoPro mount because the PP's mounting prongs are too wide. I tried to wiggle it in for a while but all I achieved was to gouge away some of the plastic from the PP.

I've read somewhere on here that you can open up a tight GoPro mount with a carefully applied screwdriver. I gave that a go and even smeared some grease on the PP's mounting faces. I got it further in then discovered that the square edge of PP's mount bottoms out in the GoPro mount before the holes are anywhere near alignment.

Now k-edge are the market leaders in cycling computer mounts, and I'm pretty sure that many of your customers will be using them. The fact that I cannot find not a single complaint about them in this forum leads me again to the conclusion that, somehow and inexplicably, the unit I received was manufactured out of normal tolerances.

So, to recap, the mounting holes on the PP I received were too small for the mounting bolt to go through, and now I find I cannot mount it in the market leading GoPro combo mount. I'm very close to sending the PP back to the UK retailer and submitting a review to explain why. Before I do that, is there anything you can do to help?

Thanks in advance.

Oh, quickly returning to the mount cost, this is definitely a hidden cost in my opinion. A good CNC'd mount in the UK is at least £40 and probably more. A good deal on a k-edge combo is still £50+. I have 3 bikes, so that's £150 extra on mounts I didn't take into account when weighing up my purchase. The PP supports 4 bike profiles, so some may want/need 4 mounts. You're very much in the region of other power meters by then. (In fairness I did read one review that pointed this out. I just didn't do the maths before buying.)

[Velocomp]

We used to source our combo mounts from K-Edge, so I am very surprised if they do not work.

We have not changed the tab design of our GoPro mount since we introduced it 5 years ago, so whatever has changed has been in the K-Edge mount design. Doubtless they did this to reduce their manufacturing costs. We cannot be responsible for changes that others make...

We sell our combo mount for $59 ($48 for the first bike); if you want 4 of them we will cut you a break (email tgore@velocomp.com for details). But you don't need a combo mount to use our product; a regular handlebar mount for $30 or less will do just fine.

We manufacture our plastics in high volume, all at the same time. I do not see ANY way that the tabs could be out of tolerance, particularly in the manner you are suggesting (too thick). Such a problem would make it impossible for the part to be released from the mold used to manufacture it.

To do the 4 bike math properly, you need to factor in the cost of 4 separate power meters for 4 bikes. Or alternatively, the "cost" of time spent manually moving the DFPM from bike to bike, including the cost of recalibrating the DFPM every time you move it. And the wear and tear cost on your bikes and DFPM each time you physically move it. And, of course, this thought experiment assumes that the same DFPM will work on all 4 bikes, which is almost never the case.

[doib]

If it can help, I have had the same problem with a support from another company (not k-edge), to be mounted under the original garmin support. After unsuccessfully trying to align the holes, I realized that the holder was too short to fully insert the PP attachment. I think there are on the market supports for gopro or other manufacturers of similar but not identical actioncam or of some previous series, not compatible with pp and (probably) not even with the latest gopro. To be precise, it is about this model:

https://www.amazon.it/gp/product/B01HTP ... UTF8&psc=1,

which does not allow the mounting of the pp although the attack looks similar.
In short, I would say that the problem is the third party supports and not the PP.

[andyjw]

Thanks for the replies.

What I omitted to say in my previous post (because it was long enough already) is that I've purchased and tried a number of mounts. Six in total, including the one that came with the PP. They have all been very very tight. Sufficiently so in fact that I have greased the PP to reduce the risk of damaging it, although it is already looking somewhat worse for wear.

The mount that came with the PP was marginally easier than others because of the chamfered middle prong, as mentioned in a previous post. However, it still needed grease to make it easy to line up the mounting holes. Without the grease it was a mission to mount.

The K-Edge mount was the tightest fitting, and the only one that bottomed out. But it also feels by far the most robust, and given I'm hanging £100s of GPS and PP off it, that matters. I had my hopes pinned on this one.

Another mount had the opposite issue. It never bottomed out and was so deep that I could pretty much point the PP at the floor. Not great for getting consistency of positioning.

What all this tells me is that the PP is far more sensitive to the quality of mount than a GoPro, which is kinda obvious really given it needs to be positioned accurately. Still, I'm surprised no one else has posted about the issues I've had, unless there is an issue with my unit, which John is adamant there can't be. (I obviously disagree, but hey ho.)

With regards to the standard mount being cheaper, that's all very well, but I don't want the PP hanging under my handlebars. It looks sh*t, and I'm sorry, but aesthetics matter. It's also insanely expensive to purchase direct from Velocomp from the UK due to shipping costs. At present I have an out-front mount in my basket at $59.95 and shipping costs of $67.55!

To set out my stall, I want to love the PP. I really do. I'm a physicist by training and from a family of engineers, so I'm fascinated by the science here, and I also understand John's points about large batch manufacturing and others not reporting similar issues.

HOWEVER, the fact is still that I cannot get the mounting bolt into the unit without grinding it through the plastic, and I have yet to find a mount that isn't extremely tight, to the point of damaging the PP. I bought the PP to switch between a few bikes, but based on my experience so far it'd be quicker to switch pedals, and I'd have a lot more confidence they wouldn't break (because pedals aren't plastic). Fundamentally I think that's my biggest beef - that I just don't see the PP lasting very long given the amount of force and effort it takes to mount. At some point something's going to give.

I will contact Tom to enquire about getting a Velocomp mount from the US to try. I have also started the returns process here in the UK, as I'm not prepared to faff about with this much longer.

[Velocomp]

If you want you can send your unit to us, along with your mount. We would be glad to take a look and see if anything is amiss.

We have thousands and thousands of this design in the marketplace, and as you point out there are very few problems. We want to be helpful and if there is something we can do to resolve this we will. Please email tgore@velocomp.com for next steps.

[andyjw]

Hi John. I already emailed Tom so I'll wait to hear back. Cheers for the prompt response.