Power Meter Recommendations- might need new Crankset

[cruzKurt]

I started investigating power meters for my 2019 v20. I thought a single sided crank-based system might be a good start. I went out and did some ID on my crank arms and they are SRAM APEX - GXP but they have been shortened. I assume I need a new crankset with a compatible single sided power meter. Any recommendations would be greatly appreciated. I would prefer the shortest crankset I can get that is compatible with a power meter.

 

[Beano]

SRAM Quarq, shop around and you should be able to find one that is compatible with your GXP bottom bracket. Shortest crankarm is 165mm.

 

[cruzKurt]

SRAM Quarq, shop around and you should be able to find one that is compatible with your GXP bottom bracket. Shortest crankarm is 165mm.

Thanks, SRAM site says "Must use Quarq DZero DUB crankset and SRAM DUB bottom bracket", then it goes on to have me pick a DUB bottom bracket. I will then need shell width, if the shell is threaded and also the ID of the shell to choose. I guess I can look at the BB that is currently installed and get that info.

https://www.sram.com/globalassets/document-hierarchy/compatibility-map/road/dub-choose-a-road-bottom-bracket-compatibility-map.pdf

 

[M.J]

I have a set if Garmin Vector pedals. They work great and you can use them with any crankset.

 

[Frito Bandito]

I initially bought a 52/36t Shimano R7000 groupset with 165mm cranks. It's heavier than Dura Ace and Ultegra, but durable. I swapped out the small 36t ring for a 34t, and then bought a left side 165mm 4iiii Power Meter crank arm (about $300). It works great, the battery lasts at least 6 months, and it paired with my Wahoo Bolt very easily. If you are ONLY going to use the Power Meter for 1 bike, then it is a great one to buy.

However, I have a DF bike that I sometimes would love to compare against my V20, and to do so with any sort of accuracy would require a power meter that I could swap over easily. These could be easily done with pedal based power meters. At the time of purchase I figured my DF days were 100% over. I still ride my V20 95% of the time, but comparing my specific speeds/power between my 2 bikes is fruitless. Pedal based PMs might be cheaper now, so buying them now is something to consider.

 

[vosadrian]

I'm with the others here suggesting pedal based power meter. They fit to any bike without exception. You can upgrade your cranks at any point and not have to worry power meter compatability. I think this is particularly relevant on a bent, as you want to run shorter cranks than average on a DF, and crank availability for short cranks is hard enough without adding a requirement to support a PM also. You can even fit them to your kid's bikes! I run Garmin Vectors on my V20. My DF bike has Garmin Vectors I got back in 2015 and still working great. Admittedly there were some firmware issues earlier on when the first Vectors came out, but they cleared that up with SW upgrades after a year or so and I have not had further issues. Just replace the battery every few months and that is it! I just use cheap batteries that cost me a dollar or two when I change them.

 

[cruzKurt]

I initially bought a 52/36t Shimano R7000 groupset with 165mm cranks. It's heavier than Dura Ace and Ultegra, but durable. I swapped out the small 36t ring for a 34t, and then bought a left side 165mm 4iiii Power Meter crank arm (about $300). It works great, the battery lasts at least 6 months, and it paired with my Wahoo Bolt very easily. If you are ONLY going to use the Power Meter for 1 bike, then it is a great one to buy.

However, I have a DF bike that I sometimes would love to compare against my V20, and to do so with any sort of accuracy would require a power meter that I could swap over easily. These could be easily done with pedal based power meters. At the time of purchase I figured my DF days were 100% over. I still ride my V20 95% of the time, but comparing my specific speeds/power between my 2 bikes is fruitless. Pedal based PMs might be cheaper now, so buying them now is something to consider.

Frito,

When you switched to Shimano Groupset, did you have to get a new Bottom Bracket? I have SRAM on my bike, but there are some interesting options with Shimano. Thanks, Kurt

 

[cranky cyclist]

I have the Favero Assioma power pedals. The meter is left side only and costs about $375. I have had no issues with them. You can also upgrade to a Right side meter as well so power is being measured on both sides. This will then tell you how balanced your pedaling is.

 

[Frito Bandito]

Frito,

When you switched to Shimano Groupset, did you have to get a new Bottom Bracket? I have SRAM on my bike, but there are some interesting options with Shimano. Thanks, Kurt

Kurt,
Actually, my V20 came with a 10-speed Shimano Tiagra triple crankset that I learned on. After a short while I bought the R7000 105 groupset, and Dura Ace cups for the Bottom Bracket. I put almost 14,000km on the 105 groupset last year, and near the end of the year I bought a 12-speed SRAM Force AXS brifters and derailleurs. However, there were no SRAM cassettes, SRAM cranks or SRAM chains in stock, so I bought an Ultegra 12-speed cassette, a Shimano Freehub and a KMC chain. I kept the Shimano 105 crankset on and it works perfectly. I hear that SRAM AXS works with 12-speed Campagnolo cassettes and cranks as well. As for the cups though, I just matched them with the crankset and you should be fine.

 

[chicorider]

Hi Kurt,

SRAM and Shimano use different bottom brackets. They look similar, but they aren't. Shimano uses a straight 24mm crank spindle, while SRAM's GXP spindle is 24mm on one end and 22m on the other.

 

[TransAm]

Thanks, SRAM site says "Must use Quarq DZero DUB crankset and SRAM DUB bottom bracket", then it goes on to have me pick a DUB bottom bracket. I will then need shell width, if the shell is threaded and also the ID of the shell to choose. I guess I can look at the BB that is currently installed and get that info.

https://www.sram.com/globalassets/document-hierarchy/compatibility-map/road/dub-choose-a-road-bottom-bracket-compatibility-map.pdf

I just put a Quarq DZero DUB Power Meter Spider on my V20. Yes, I also had to get the DZero DUB 165mm carbon cranks, but they are relatively cheap at $211.00 (which is less than what I paid for a set of solid Al cut cranks). And the DUB BSA Bottom Bracket is only $41.00. So it's not that expensive to just replace the crankset (assuming you can re-use your chainrings).

I picked this setup because it is very lightweight. Not that I'm a weight weenie, but the weight on the end of the boom makes handling the bike when not riding difficult because it falls off to one side if the bike is tilted. The bike is noticeably better behaved when stopped with less weight out front. I'm not sure if this also affects handling when rolling--I didn't notice any difference.

 

[cruzKurt]

I just put a Quarq DZero DUB Power Meter Spider on my V20. ...

I found this setup online, it uses a GXP bottom bracket, I am thinking this would be all I need to upgrade to a power meter. Hopefully will sync with my bike computer.

Quarq Crankset

 

[KiwiGuy]

The Vendetta (2017 V2) is my only bike. I use a crank-based, Power2Max Type S power meter fitted to Rotor 3D 165mm crankarms - based on DC Rainmakers recommendation at the time. It just works. No hassle. Change the battery once every 12 to 15 months.

No doubt I'd be just as happy with a SRAM Quarq power meter.

Given I don't shift between two or more bikes, using a pedal based system makes no sense to me. I'd have to change or charge the batteries much more frequently. And I couldn't run double-sided mtb pedals (which is my preference on the road so I can wear cycling shoes I can actually walk safely in).

 

[TransAm]

I found this setup online, it uses a GXP bottom bracket, I am thinking this would be all I need to upgrade to a power meter. Hopefully will sync with my bike computer.

Quarq Crankset

That's 170mm, not 165mm length. I don't think it's worth getting the obsolete version just to re-use your BB bearings. If you need replacement parts, you could be out of luck. The advantage of the new DUB version is that replacement carbon cranks are only $211 if you trash them, and 165mm is available now. Also, it's easy to move to a new or second bike, because the U stands for universal. The DUB BB comes with spacers to match any standard road width setup (you can't change the axle to match road wide or MTB widths, though). The DUB also has a real lash adjuster, rather than the hokey GXP wavy washers. But you will need a new bearing cup tool to install. My LBS let me borrow theirs.

 

[TransAm]

The Vendetta (2017 V2) is my only bike. I use a crank-based, Power2Max Type S power meter fitted to Rotor 3D 165mm crankarms - based on DC Rainmakers recommendation at the time. It just works. No hassle. Change the battery once every 12 to 15 months.

No doubt I'd be just as happy with a SRAM Quarq power meter.

Given I don't shift between two or more bikes, using a pedal based system makes no sense to me. I'd have to change or charge the batteries much more frequently. And I couldn't run double-sided mtb pedals (which is my preference on the road so I can wear cycling shoes I can actually walk safely in).

Yes, the Garmin SPD pedals are way too expensive, and there are no other good options. I also use walkable shoes, because road cleats are way too impractical for self-supported riding.

I also looked at the Power2Max version, but decided to go for the Quarq because it was lighter, and I definitely notice the reduced weight at the end of the boom when moving the bike around.

 

[cruzKurt]

That's 170mm, not 165mm length. I don't think it's worth getting the obsolete version just to re-use your BB bearings. ...

Where would you purchase such a setup online? I live out in the country and there is no LBS, so I try to do things myself. Always willing to learn. Also, is it possible to shorten Carbon Cranks? I have shortened cranks on my v20 now (148mm). Thanks for being willing to share.

I guess I will need a new crankset, new sprokets (mine have seen better days), new BB, and of course the Quarq.

 

[vosadrian]

165mm is still on the long side for a V20 in its intended purpose of going fast. Many of the fast guys (like Larry) are using significantly shorter. I use 155 and want to try shorter. I think it is important before spending lots of money on a PM or crankset to at least select an option that will allow you to go to short cranks later if you decide to go that way. Most cranks I have seen seem to have a minimum of 165mm. There are only a few options that go shorter than that.

 

[cruzKurt]

165mm is still on the long side for a V20 in its intended purpose of going fast. ...

Thanks, I have been considering replacing my crankset with one that is power meter compatible. Maybe I will do that and experiment with shorter crank arms. I currently have 148 mm but no power meters that are compatible. I assume I will have to shorten the crank arms myself.

 

[TransAm]

Where would you purchase such a setup online? I live out in the country and there is no LBS, so I try to do things myself. Always willing to learn. Also, is it possible to shorten Carbon Cranks? I have shortened cranks on my v20 now (148mm). Thanks for being willing to share.

I guess I will need a new crankset, new sprokets (mine have seen better days), new BB, and of course the Quarq.

The lowest price is with Modern Bike:

https://www.modernbike.com/product-2126286144?TID=394

They also have the 165mm cranks. But as was pointed out that is still kind of long, so if you don't have long legs, you may want to reconsider, because you cannot shorten carbon cranks.

You can shorten most solid Al cranks, but they are still heavy. But it does not look like these Dzero Al cranks can be shortened because the relief slot comes too close to the hole:

https://www.eriksbikeshop.com/quarq-dzero-aluminum-power-meter-chassis-pr3e10459/p

Rotor Aldhu cranks are available now in 155mm and can be used with the Power2Max spider or the Rotor power spider.

 

[TransAm]

165mm is still on the long side for a V20 in its intended purpose of going fast. Many of the fast guys (like Larry) are using significantly shorter. I use 155 and want to try shorter. I think it is important before spending lots of money on a PM or crankset to at least select an option that will allow you to go to short cranks later if you decide to go that way. Most cranks I have seen seem to have a minimum of 165mm. There are only a few options that go shorter than that.

Yes, I was using 180mm SRAM Apex solid Al cranks shortened to 158.5mm by Mark Stonich of BikeSmith Design & Fabrication in Minneapolis, MN. But I damaged them and had to put on 175mm cranks because that was all I had as backup. Those were too long, but not too, too long, so I decided to try the 165mm. I'm more concerned with hill climbing than speed in the flats, because my power-to-weight ratio has gone to hell. I preferred 180mm cranks on my upright bikes for hill climbing too, so I decided to go longish on the V20. So far, no regrets....