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  1. #1
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    Kris Holm KH Freeride rim tubeless conversion problem

    Just wondering what your long term experience with running above rims tubeless is, especially at low pressures.

    I've just converted mine using two layers of Gorilla tape and Stans sealant.
    They hold air pretty well, but they burp extremely easily even without trying too hard and the tyre fit (Racing Ralphs 2.40) is worryingly loose.

    I wonder whether it's a simple matter of adding extra layers of tape or it's better to go with a split tube method or they are rubbish rims for tubeless conversion. Perhaps Racing Ralphs don't like to be pushed too hard at 20PSI?

    Ideally I'd love to be able to run my tyres just below 20PSI at the front and just above 20PSI at the back for comfort (fully rigid Scandal + 210 lb rider). Regular XC, trail riding, no snow.
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  2. #2
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    Quote Originally Posted by Barteos
    Just wondering what your long term experience with running above rims tubeless is, especially at low pressures.

    I've just converted mine using two layers of Gorilla tape and Stans sealant.
    They hold air pretty well, but they burp extremely easily even without trying too hard and the tyre fit (Racing Ralphs 2.40) is worryingly loose.

    I wonder whether it's a simple matter of adding extra layers of tape or it's better to go with a split tube method or they are rubbish rims for tubeless conversion. Perhaps Racing Ralphs don't like to be pushed too hard at 20PSI?

    Ideally I'd love to be able to run my tyres just below 20PSI at the front and just above 20PSI at the back for comfort (fully rigid Scandal + 210 lb rider). Regular XC, trail riding, no snow.
    That rim was neither designed nor intended to be run tubeless.

    For that matter, neither were those tires.

  3. #3
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    I'm well aware of that.
    I've done several successful Stans and ghetto conversions before, using "inappropriate" components and I've never had a problem.
    Until now...
    www.bartthebikeman.wordpress.com
    fast 26" road bike, shaven Racing Ralphs as road tyres, homemade "Paul thumbies"...

  4. #4
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    The rim tends to fit tires loose. You'll have to add more layers to build up the bead if you want it work.

  5. #5
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    I found those rims to be the easiest rims to tubless by a mile and have not burped once (even run as low as 8 PSI).

    I use the split inner tube method.

    I have used WTB Dissent, WW 2.55 and Stouts.

    I weigh 220lb.

    I would guess the RR are a bad fit. Shame I was just about to buy some =-(

    Try one of the WTB tyres and see if that helps (please PM me if it fixes the issue as then I know to avoid RR).

    No issues with any of those tyres.
    Why would I care about 150g of bike weight, I just ate 400g of cookies while reading this?

  6. #6
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    Thanks guys
    I'll try extra few strips of tape first and then if it doesn't work, a split tube.
    I'll let you know how I get on.
    www.bartthebikeman.wordpress.com
    fast 26" road bike, shaven Racing Ralphs as road tyres, homemade "Paul thumbies"...

  7. #7
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    I tried them with the split tube method and WW255lt and Saguaro. They would hold for about four hours, seeping around the bead, so laying on buckets. Then they would let go around the upper bead, spraying Stan's across the garage walls and ceiling, and scaring the bejusus out of me and my trusty four legged mechanic helper. Happened three times and I gave up. Dog got to the point where she was out of the garage at the end of the driveway every time I touched a wheel or the compressor.
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  8. #8
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    My experience was identical to CaveGiant using a split 24" tube. I can only guess these rim have changed significantly to be causing the problems described.

    I purchased my 29" rim through unicycle.com about one year ago. The fit of any tire I have mounted was TIGHT. So tight in fact, that good tire irons are required for removal.

  9. #9
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    +1 on good tyre levers, getting my dissents on took a lot of effort
    Why would I care about 150g of bike weight, I just ate 400g of cookies while reading this?

  10. #10
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    So far so good
    With two layers of Gorrila tape and split tubes it's holding air fine and I managed to pump up it up just with a floor pump.
    After having tested them on a urban "singletrack" (=carpark, cobbles etc..) 16PSI, 20PSI,
    I think I may start trusting them.
    I have a pair of WTB WWs 2.55 coming and I'll check if the fit is any different than with RRs.
    www.bartthebikeman.wordpress.com
    fast 26" road bike, shaven Racing Ralphs as road tyres, homemade "Paul thumbies"...

  11. #11
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    After many failures with KH FR rims, I think I finally got it down. I made my own rim strips out of two strips of EPDM rubber, 3/32" thick x 2" wide (McMaster-Carr p/n 8985K13, $5.57 each). I trimmed the width down to 1.70" so it just fit between the walls of the rim. I bonded the ends together with Loctite 404 Super Glue for rubber (McMaster-Carr p/n 7569A22, $22.49) to make one big rubber band. I got a 1-1/16" round hole punch, and an ensolite pad (blue camping mattress pad) and punched out 30 some disks of material to fill the cut out holes in the rim. This only adds 9 grams/wheel, supports the rim strip, and helps keep dirt/mud/water/sand from getting in between the rim walls. Rim strip goes on next, then a motorcycle style tubeless valve stem. I mounted a tube and tire, pressurized it to 25 psi and left it for a couple days. This helped compress the foam disks a bit so they didn't stick up under the rim strip. The tire fit was very tight, getting it on over the rim strip. I really had to work at it, and almost had to use levers.

    When I took the tube out, I lubed the bead with soapy water (no Stan's yet), and it aired right up. I used a compressor, but I reckon it would have worked with a floor pump too. The tire held air for 30 minutes WITHOUT Stan's. Put Stan's in, and I have lost maybe 1 or 2 psi in three weeks. I couldn't expect better with a tube. I have done this with an Ardent 2.4 (first), and just recently with a RR 2.4. The RR sealed up just as well as the Ardent, but as of right now that was only 1.5 weeks ago. After it's maiden voyage through sharp rock gardens and hub deep creek crossings, it's doing just fine. No burps at all. I weigh 220 and run these at 20 psi.
    JW

  12. #12
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    Wow you put a lot of effort in there, quite commendable.

    I just put a tube on, split it, then mounted the tyre easily.

    Not sure where the issue was?
    Why would I care about 150g of bike weight, I just ate 400g of cookies while reading this?

  13. #13
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    I am looking for a strong, wide 26" rim that is durable for Downhill riding. I rollin in @ 6'1" about 265 with all my gear & my bike weights about 45.

    I run 2.7" tires and have yet to find rims wide enough to create a good profile. The widest downhill specific rims i could find were the Sun-Ringle MTX 39, however their internal width is only 30mm. I want to run a tubeless (normal Stans or Ghetto Tubeless w/Stans) so I can run low tire pressure, yet keep a good sidewall for cornering/high speed stability...

    1) Could someone with Kris Holm KH Freeride rims comment on the strength (having holes drilled in my rim concerns me)

    2) can anyone measure the internal bead width? I know the external is stated as 47mm...

    Any suggestions??

  14. #14
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    Trials wheels take the biggest hits and largest tyres. They normally land with one wheel taking all the force (Kris Ho,m definately does ;-) )

    Holes are not an issue, they enable the use of thicker metal else where in the wheel without compromising weight.

    So this would be perfect if you were riding 29", cos last time I checked, they do not make this 26".
    Why would I care about 150g of bike weight, I just ate 400g of cookies while reading this?

  15. #15
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    My bad, they do make 26", I thought it was just 19,20,24 & 29.

    Watch videos of Mr Holm and you will see how strong they are.
    Why would I care about 150g of bike weight, I just ate 400g of cookies while reading this?

  16. #16
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    So I asked KH a few similar questions, here are their responses:

    ME:
    "I am in need of a set of wide and strong 26" wheels to use for Downhill mountain biking.It seems as though your KH Freeride rims would be a perfect match for what I need. I would be using 2.7" Downhill specific tires. I had a few quiestions for you:

    1) If the material was not removed from the rim, would they be stronger? Is it possible for me to obtain a set without the "oval" material removed between the spoke holes?

    2) What is the inner bead width of the FR rims?

    3) Where in the US can I purchase teh FR rims? "


    KH:
    "1) Yes if there were no drillouts they would be somewhat stronger, but quite a bit heavier. The size of the drill holes is intended to balance weight and strength as on the unicycles they're not downhill-specific - they're targeted at freeriding but still need to be light enough for climbing. That said they are still in the "strong" category compared to many bike rims. KHU doesn't offer an undrilled version.

    2) Inner minimum bead width is 40 mm, and depth of the rim profile (total depth) is 20 mm.

    3) Unicycle.com USA would be the first place to try, to order these rims. "

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