• 06-28-2014
    plume
    9 Attachment(s)
    WTB KOM 29" Rim - wheel build review
    Because there's little information on WTB's newer KOM rim series, I thought I would add a review from a mechanic and wheel builder's perspective. I'll add my thoughts as a rider once I've had a chance to ride them for a few hundred miles or so...

    After much deliberation and a decision to not use a carbon rim, I finally landed on the WTB KOM 29" alloy rim - the goal was a sub-1700 gram 29er wheel set after using a tried and true 2000 ish gram set of Kings/Flows for everyday riding, and having extremely bad luck with a set of low spoke count system wheels. I wanted something in the middle that would be good for race day, yet reliable for moderately aggressive descending or every day use.

    DT Swiss got the vote for weight, serviceability, and reliability in the hub department - 240s c-lock, thru axles:

    Attachment 904411Attachment 904412

    The rims came in 12 grams of one another, fairly light actually:

    Attachment 904413Attachment 904414

    I have access to a Phil Wood spoke cutter and have since switched to using Wheelsmith spokes as they tend to cut and roll very nicely and consistently. For this build I went against my usual brass only rule for mountain wheels and went with a nice blue alloy Wheelsmith nipple and prepped the spoke threads with Rock 'n' Roll nipple cream. The project pre-lacing:

    Attachment 904415

    After lacing, I weighed both wheels individually before the build:

    Attachment 904416Attachment 904417

    Weight goal achieved! Front 767g, Rear 879g, Set 1646g - quite svelte but hopefully dependable as well.

    I've built a lot of Stan's products over the years and usually end up with a decent set of wheels, but I never liked how the Arch EX built up, and the Flow's while a great set of rims, are just heavy, great for training and descending, but a little bit of a bear on extended climbs. The KOMs built up with a strong grade of B+ The tension on the front wheels drive side was a little lower than I would have liked, and there was one flaky spoke that was doing odd things at the spoke bed. Still easily a passing grade over all. The rear went smoother and more predictable. 115 Kg on almost all drive side spokes and most non-drive were evenly distributed around 100 Kg. I'd love to build a few more sets up, better than the Arch EX, not quite as stable as a Flow EX...

    but... the real review is in the ride:

    Attachment 904418Attachment 904419

    After the shake down ride, they get a quick and enthusiastic, YES. Not quite as stiff as my lovely Flows, however the acceleration and weight will more than likely make up for it. These will see racier tires with more PSI than I typically run for fun trail riding, but that was the plan. So far I'm very happy. I plan on abusing them on one of the longest descents on the east coast tomorrow and I will update this thread with a longer term review of the rims and wheels. Thanks!
  • 07-01-2014
    Rhialto
    Thanks for the write-up. Great photos, too. I'd be interested to hear how they fare long term. I was looking at these rims to build a light wheelset but there are reports that the KOMs are a bit fragile.
  • 07-01-2014
    ejreyes6
    Any issues mounting the Maxxis or Schwalbe's on the rims?
  • 07-01-2014
    Mac_Aravan
    Quote:

    The rear went smoother and more predictable. 115 Kg on almost all drive side spokes and most non-drive were evenly distributed around 100 Kg.
    How can it be possible?
    240CL have 100/60% tension distribution, so with 115kg on drive side, you should be at 70kg non drive side.
  • 07-01-2014
    dgaddis1
    Quote:

    Originally Posted by Mac_Aravan View Post
    How can it be possible?
    240CL have 100/60% tension distribution, so with 115kg on drive side, you should be at 70kg non drive side.

    I was thinking the same thing. Something isn't quite right with those numbers.

    I've built half a dozen sets or so of the KOM rims and like them a lot. I think the people who've had durability issues are the ones who believed the inital WTB marketing that these were 'enduro' rims with strength equal to a carbon rim and they were indestructible, etc. There's no beating physics - these a light-ish XC/trail rims, not burly AM/Enduro rims. However, I think they strike a really nice balance of weight, stiffness, and width.

    If I were building myself another set of alloy rim'd MTB wheels, it would be with the KOMs.
  • 07-01-2014
    plume
    Quote:

    Originally Posted by Rhialto View Post
    Thanks for the write-up. Great photos, too. I'd be interested to hear how they fare long term. I was looking at these rims to build a light wheelset but there are reports that the KOMs are a bit fragile.

    I'm sticking to some higher pressures to hopefully avoid any rim damage. thanks!

    Quote:

    Any issues mounting the Maxxis or Schwalbe's on the rims?
    Not really. I've taken to simply removing the valve cores on all my tubeless set ups upon the initial inflation. No issues that way. I think the Schwalbe's tend to be the fussiest but w/ no valve that hook right up.

    Quote:

    How can it be possible?
    240CL have 100/60% tension distribution, so with 115kg on drive side, you should be at 70kg non drive side.
    Yep. I was thinking front when I posted that, just flat out wrong sorry. Wishful thinking but your numbers are the reality. I'm going to throw them in the stand later today to check how the last 3 rides have effected them.
  • 07-01-2014
    coombs
    What specifically about the Arches bothers you? Not a critical question, just a curious one.
  • 07-01-2014
    plume
    Quote:

    Originally Posted by coombs View Post
    What specifically about the Arches bothers you? Not a critical question, just a curious one.

    They have been inconsistent, I have seen and built some that tension up nicely and I've had to send some back because the inner wall must of had some inconsistencies. This is no knock on the product in general and it's a universal acceptance that a lighter rim will inherently be more challenging to work with.

    At the end of the day? I want another option I can refer my customers to - some of them have had issues with Stan's products that I haven't experienced. So far I think the KOM rim is a nice alternative to the Arch EX...
  • 07-01-2014
    plume
    Front wheel with actual deflection reading after 3 fairly rocky rides averaged 110-120 Kgf disc side, and 80 - 90 Kgf drive side. Rim was within 1 mm laterally. I'm using a Park Tool TM-1 so yeah... :)

    Rear wheel 100 - 110 Kfg drive side. 60 - 80 non-drive, meh. so more realistic numbers wheel builders (instead of plucking from the air or wishful thinking), rim was within 1.5 mm laterally. Just checking them both out with tires on thus far.

    In other words, I'm happy so far. I feel like they have a nice and lively feel largely due to the weight but without being overly whipy in corners. I'm probably 170 lbs with gear and am playing with higher PSI as I've damaged some rims recently. I'm around 28 psi rear, and 25 psi front. For racing I'm sure it's the right answer. For fun, I like a LOT less of course it's all dependent on tire volume and now, rim selection...

    As an aside the engagement on the DTs isn't as lightening quick as I'm used to with Kings/I9s but damn do they roll quick. I was hoping that they would come with the updated ratchet but I don't believe they did. There was more than once when I clumsily shifted gears or pedaled out of something techy that the hub gave me that knocking sound that I'm just not accustomed to. Not a big deal. I'll take reduced drag over hub engagement at least for the purposes of these wheels. Obviously these are my first DTs, always lusted, never purchased. They nice.

    I'll post more in a few months. I have a few endurance races coming up this summer...
  • 07-08-2014
    hoolie
    Plume, thanks for this post. I was going to ask which hubs you had experience with, but post #9 explains it, cool. Keep us updated.
  • 07-10-2014
    dustyduke22
    I have been on a set of KOM's since the beginning of the year and have been very pleased. I recently built me up another set for my new Canfileld Yelli Screamy a little over a month ago and have been oh so pleased!

    I raced on them at a local Enduro race and just returned from a trip down to Southern Utah where I grew up. After one especially gnarly trail, I stepped off the bike and spun the back wheel expecting to see some carnage. To my surprise, I spun the wheel and it was still dead true.

    These light rims have impressed me to no end. I have no problem pushing the hardtail into rocks and drops now. They have my stamp of approval.

    Don't know if anyone knows yet, but WTB is coming out with a KOM i25 (25mm internal width) with 29er weights ~460g per rim. Cant wait!!!
  • 07-10-2014
    dgaddis1
    Quote:

    Originally Posted by dustyduke22 View Post
    Don't know if anyone knows yet, but WTB is coming out with a KOM i25 (25mm internal width) with 29er weights ~460g per rim. Cant wait!!!

    That's gotta be a typo right? The 23mm 29er versions I've built were all right around 460g, I'd be surprised if the 25mm versions were the same weight.

    WTB originally said the 23mm would be like 420g, but after some testing they added some beef for the production rims.
  • 07-10-2014
    changingleaf
    The WTB 29in Frequency i25's I just built weighed 557g and 565g. 100g is a lot of weight to take off of the rim, but it can be done. I image the profile depth on the KOM will be a lot shorter than that of the Frequency.
  • 10-25-2014
    plume
    Got a summer's worth of riding on these and I'm very happy with them, so happy that I've built another set with their KOM i25 rims and 350 hubs this time around. Wheel set weight is hovering just over 1800 grams (29") with c-lock hubs, DB wheelsmith spokes and brass pro lock nipples. Geared more towards enduro or trail use this time.

    The original wheels posted in the thread have required little maintenance and while I haven't pushed the envelop with low PSI I'm not running anything higher than 20 psi even for racing (I'm 160 lbs) so I'm pleased, no dings, rolling true. I ride fairly technical trails when given the chance...

    With these new wheels I plan on abusing them a bit more with lower pressures to improve some DH times... and fun. The build is decent but I am concerned with the seam, heat sink, weld as after bring the wheel to 120 Kg drive side I'm getting what I hope is only paint cracking right at that seam. I'm a little wary of this but I'll keep this thread updated.

    As an aside I'm finally going to adapt these dt hubs to the 36 step star ratchet as they are SLOW to engage with the 18 step... hope it makes a noticeable difference since that little upgrade retails for $120!!!
  • 10-25-2014
    silent713
    Glad to hear that people are pleased with the KOM rims. I'm about to have a set of wheels built up using KOM25s and some 32h CK hubs I had from an older 26" build. Looking forward to riding these things!!
  • 10-26-2014
    Cenzobear
    WTB KOM 29" Rim - wheel build review
    I just built Up a set of these on Friday, with King hubs. I have to say I totally agree with you. It really makes for an amazing set of sturdy wheels.

    Setting them up with Specialized 2bliss tires though. Be warned....


    Sent from my iPad using Tapatalk HD
  • 10-26-2014
    silent713
    Quote:

    Originally Posted by Cenzobear View Post
    Setting them up with Specialized 2bliss tires though. Be warned...

    Care to elaborate? I was planning on running a Purg/GC combo in 2.3 on these.
  • 10-26-2014
    Cenzobear
    WTB KOM 29" Rim - wheel build review
    I just had a really hard time getting my tires to seat. My setup was a Fast Trak Conrol 2.0 up front and an S-Works Fast Trak 2.0 out back. I taped the rims with WTB's 28mm tape, as per their recommendation.

    I had zero success mounting the tire, removing the valve core, and using a compressor. The tire wouldn't even come close to seating. The only way I got them to seat was by having three other guys in the shop basically hold the tire onto the rims as I inflated them. Once I got them inflated though, they held air perfect. No shaking needed. I'll also add that the bead always sits just a hair uneven when fully seated. Making the tire roughly 4-5mm out of round.

    So, in short, it can be done, just not easily and not in the field.


    Sent from my iPhone using Tapatalk
  • 10-26-2014
    changingleaf
    Those rims are designed for tires with a UST bead so unless you chose the Specialized Grid UST tires you're going to have trouble. The Specialized 2bliss tires have a larger bead than their grid UST tires so they are not the right choice for that rim. Some tubeless ready tires will inflate easier such as, Geax TNT, Hutchinson Tubeless Ready and of course WTB TCS tires.
  • 10-26-2014
    Cenzobear
    WTB KOM 29" Rim - wheel build review
    Quote:

    Originally Posted by changingleaf View Post
    Those rims are designed for tires with a UST bead so unless you chose the Specialized Grid UST tires you're going to have trouble. The Specialized 2bliss tires have a larger bead than their grid UST tires so they are not the right choice for that rim. Some tubeless ready tires will inflate easier such as, Geax TNT, Hutchinson Tubeless Ready and of course WTB TCS tires.

    You hit the nail on the head! I just used the 2bliss tires as they were what I had, and they still have a lot of life left in them.

    I think the design on the rim bed also has a lot to do with it. Stan's style rims have a very shallow divot in the rim bed, which helps the close the gap between tire and rim more tightly, allowing them to seal. The WTB rims have a very deep channel, which let's the tire sort of flop around on the rim. And yes, they do indeed fit a little bit looser, that's where the bead irregularity comes from. I'll bet another wrap of TCS tape would fix that


    Sent from my iPhone using Tapatalk
  • 10-26-2014
    silent713
    Interesting. Any experience with Conti tires on these rims?
  • 10-26-2014
    Cenzobear
    WTB KOM 29" Rim - wheel build review
    Quote:

    Originally Posted by silent713 View Post
    Interesting. Any experience with Conti tires on these rims?

    Not as of yet for me, but back when I had flows(it seems the OP and I have very similar trains of thought here!) they were insanely tight on them, so I would assume they wouldn't be too bad of a hassle to mount up.


    Sent from my iPhone using Tapatalk
  • 10-26-2014
    aerius
    I've tried the Conti Mountain King II and Trail King in the Protection version on a 26" KOM rim. They aired up fine and snapped into place nicely with a floor pump, nice & even, no wobbles, held air fine, piece of cake. I went back to tubes though since I change tires often enough that messing with sealant is a hassle I don't want to deal with. I used a single layer of fiber reinforced packing tape as the rim tape, I had some lying around and didn't feel like buying a roll of actual tubeless rim tape.
  • 11-02-2014
    silent713
    My wheels were built up this last Friday and I've managed to get two rides on them so far. Went with 32h i25 KOMS laced to CK hubs that I had laying around from an older bike. Slapped my existing Spec Prug/GC combo on the wheels and have been really happy with them so far. Started yesterday's ride out with 22psi in the front, and 25 in the back. Stopped twice during the ride to let a little air out. Plan to take them back to the shop on Wednesday so they can check them over and re-balance them if needed. So far so good. These things are MILES ahead of the crappy Easton wheels that came on my bike!
  • 11-02-2014
    urmb
    Thanks Plume. You influenced my next build. What was your spoke count for the wheels? I am looking to go 28h on the next build for cross country riding. Have you seen any issues with 28h?

    Thanks,

    urmb
  • 11-03-2014
    WoodstockMTB
    Quote:

    Originally Posted by silent713 View Post
    My wheels were built up this last Friday and I've managed to get two rides on them so far. Went with 32h i25 KOMS laced to CK hubs that I had laying around from an older bike. Slapped my existing Spec Prug/GC combo on the wheels and have been really happy with them so far. Started yesterday's ride out with 22psi in the front, and 25 in the back. Stopped twice during the ride to let a little air out. Plan to take them back to the shop on Wednesday so they can check them over and re-balance them if needed. So far so good. These things are MILES ahead of the crappy Easton wheels that came on my bike!

    What was the weight on this build? I'm considering KOM with I9 or CK hubs. What spokes did you use?
  • 11-03-2014
    silent713
    Didn't weigh them before they were set up on the bike, but I'm estimating they are in the low/mid 1800s using DT Comps and alloy nipples. Weight wasn't the driving force behind this build, as I have a set of I9 Trail24s on their way.
  • 11-03-2014
    rfxc
    I built a set of 29er KOM i23 rims this summer, to DT hubs. Love them! Curious, does anyone have a REAL weight of the new KOM i25 29er rim? The advertised 465g (on QBP online catalog) seems too good to be true.

    I'm considering KOM i25's laced to DT hubs with cx-ray spokes for an enduro race wheelset.
  • 11-03-2014
    06HokieMTB
    My KOM i25 650b was 13g heavier than advertised, 451g
  • 11-03-2014
    rfxc
    Quote:

    Originally Posted by hokiebrett View Post
    My KOM i25 650b was 13g heavier than advertised, 451g

    I assume that as a 650b rim? The i25 KOM 29er rims are listed as 465g on QBP.
  • 11-04-2014
    Cenzobear
    Quote:

    Originally Posted by WoodstockMTB View Post
    What was the weight on this build? I'm considering KOM with I9 or CK hubs. What spokes did you use?

    To possibly answer your question, my setup was as follows:

    Font:
    WTB KOM i23 29"
    Chris King ISO(sd) 9x100
    DT-Swiss Competition Spokes (291mm)
    DT-Swiss Alloy red/black nipples
    WTB 28mm tubeless tape
    WTB Alloy tubeless valve

    Total Weight: 840g

    Rear:
    WTB KOM i23 29"
    Chris King ISO 10sp 10x135
    DT-Swiss Competition Spokes (291mm)
    DT-Swiss Alloy red/black nipples
    WTB 28mm tubeless tape
    WTB Alloy tubeless valve

    Total Weight: 1008g

    These were measured on he crappy park tool hanging scale, not the nice accurate plate scale. Gotta say though, they came out roughly 80g heavier than I expected, not sure how... :skip:

    EDIT: Wait, never mind, that was an error in my spreadsheet :)
  • 11-04-2014
    dgaddis1
    Those weights include the tape and valve? You came out lighter than I'd expect if that's with the tape and valves. My spreadsheet predicts 845g for the front and 1,006g for the rear, not including tape or valves.
  • 11-04-2014
    dustyduke22
    Quote:

    Originally Posted by dgaddis1 View Post
    Those weights include the tape and valve? You came out lighter than I'd expect if that's with the tape and valves. My spreadsheet predicts 845g for the front and 1,006g for the rear, not including tape or valves.

    I have seen different figures from multiple people from complete build weights from 1700 to 1850 grams depending on the scale. I think that the weight is closer to what you calculated........
  • 11-04-2014
    dgaddis1
    Quote:

    Originally Posted by dustyduke22 View Post
    I have seen different figures from multiple people from complete build weights from 1700 to 1850 grams depending on the scale. I think that the weight is closer to what you calculated........

    Yeah I don't have any 29er actual build info handy at the moment, but I'll look back at some of my past builds and share some of the weights later. My spreadsheet is typically pretty dang close tho, component weights are based on typical actual weights if I've built with the part before (claimed weight if I haven't), and it accounts for spoke length.
  • 11-13-2014
    CDIDriver
    Panaracer Rampage 29er Tire?
    Does anyone know or have personal experience/success mounting and riding the 29r Panaracer Rampage on a WTB KOM i25?

    Also, I am on the fence with the KOM i25 and the Frequency i23...any real world weights, build and ride differences between both rims?


    Quote:

    Originally Posted by changingleaf View Post
    Those rims are designed for tires with a UST bead so unless you chose the Specialized Grid UST tires you're going to have trouble. The Specialized 2bliss tires have a larger bead than their grid UST tires so they are not the right choice for that rim. Some tubeless ready tires will inflate easier such as, Geax TNT, Hutchinson Tubeless Ready and of course WTB TCS tires.

  • 11-13-2014
    Chuch
    Considering the Spank 295 or the KOM25 for my Troy. Spank makes it pretty clear what their rims are made for while everyone seems a bit skeptical of the KOM25. Subscribed! Based on marketing from Spank and real world data here in the thread, both are coming in at 450g for 650B.
  • 11-13-2014
    06HokieMTB
    Depending on how heavy you are or how hard you push your Troy, that Spank Oozy 295 might be a good choice. Hadn't heard of it until now.

    Looks very, very similar to the WTB KOM i25. For me, I wouldn't trust it in the rear (I'm a rear rim basher) but looks to be a great front rim option!
  • 11-13-2014
    Chuch
    I was thinking Spank until they responded to my customer service email and told me those BIG white logo's on the sides are non removable. Sorry man, but that just doesn't do it for me at all. I hate to be that guy, but I just cant do it.
  • 11-13-2014
    06HokieMTB
    The KOM logos are very subdued. Way more so than the Frequencies
  • 11-13-2014
    DeArman
    I've had my 650B KOM i25's on for a couple of months now and have loved them so far. I've even managed to case a couple of jumps and ended up with no dents thankfully. Can't remember what mine weighed exactly though. Hope Pro Evo 2's front and rear with DT Swiss spokes and nips.

  • 11-13-2014
    Back2MTB
    Quote:

    Originally Posted by 06HokieMTB View Post
    The KOM logos are very subdued. Way more so than the Frequencies

    And added bonus of wtb tires (super easy tubeless mounting fwiw) with kom rims is the wtb tire logos and the kom decals when lined up.. WTB is killing it lately in my opinion. Old school wtb ww2.55 front ,new school wtb ww 2.5 rear on kom 29x23mm this year, loving the setup.
  • 11-17-2014
    Bigrocks
    edit
  • 02-11-2015
    kylepeveto
    Has anyone had luck mounting a Maxxis Tubeless Ready (TR) tire on a KOM rim? I tried several things -- air compressor blast, mounting the tire with a tube, then removing tube. I am thinking of wrapping a ratchet strap around the tire to make the bead set, which is a trick I've heard a few people mention with other wheels.
    Right now I'm running WTB tires. They're good, but I want other options.
  • 02-11-2015
    croakies
    Trying putting a tube in, inflate, then take tube out being careful to only break one bead. The bead lock will hold one side on. Easy to seal now as all the air will work towards sealing one bead instead of both.
  • 02-11-2015
    dustyduke22
    Quote:

    Originally Posted by kylepeveto View Post
    Has anyone had luck mounting a Maxxis Tubeless Ready (TR) tire on a KOM rim? I tried several things -- air compressor blast, mounting the tire with a tube, then removing tube. I am thinking of wrapping a ratchet strap around the tire to make the bead set, which is a trick I've heard a few people mention with other wheels.
    Right now I'm running WTB tires. They're good, but I want other options.

    Whats up Kyle?!

    Ya, I ran Highroller II's on the rims, other guys I know have ridden other Maxxis tires and they were fine. Ardent, Aspen, etc. I just used a floor pump on mine.
  • 02-11-2015
    Back2MTB
    Try putting some sealant in the tire before seating the bead and use a compressor. With my KOM'S using a tube never helped, adding a scoop or two of sealant made it super easy for some reason. And yes, wtb tcs tires are butta smooth . Thumbs up!
  • 02-11-2015
    DeArman
    I have a Minion DHF in the front and an Ardent in the back with only one layer of Stans tape and the bead snapped first try. Like posted above, put some sealant in first and roll the tire on the ground to get a little sealant on the bead and they should pop right into place. I used a compressor with the valve cores still in place. Granted my setup is 27.5 but it shouldn't be any different
  • 02-12-2015
    dirtrider76
    I picked a pair of 29er KOM23's with XT hubs pretty cheap. So far they have been holding up well for me. I'm kind of skeptical of the XT hub holding up but willing to replace it if its a problem later.

    I tossed on Bontrager XR2 expert tires. 1 full wrap of Stan's tape and 2 cups sealant per tire and they beaded right up using a blow gun on my compressor. I likely could have used a floor pump though.
  • 11-18-2015
    Dictatorsaurus
    I have the i25 KOM 29's and tried mounting Ikon 2.2 and Ardent 2.25 tubeless with no luck.

    I'm using 1" Gorilla tape wrapped once.

    Any suggestions? Do I need another layer of Gorilla tape?
  • 11-18-2015
    kylepeveto
    I had trouble with a similar set-up, but I was able to get it to work with a floor pump. I'm running a Maxxis Ardent TR in the front and an Ardent Race TR in the rear. I have KOM i23s on Hope Hubs. I'm using Orange Seal 24 mm tape.
    I didn't use extra tape. I installed each tire with a tube to let the tire take shape. One of the tires set up easily. For the other, I tightened a ratchet strap around the tire to pop the bead out and aired it up with a floor pump.