Rise - RAD measurements?

[Jfive]

Greetings! I've decided to purchase an Orbea Rise H30 but having some trouble deciding on the size to purchase. There are no Orbea dealers within 2 hours/140mi from me and the dealer that is closest won't have any in stock for a few months, at best. Thus, I need some help from the community so I can get my first emtb!

What is the RAD (Rider Area Distance) for your Rise? I'm deciding between Medium and Small but I'd like to use this post as a point of reference for all Rise members so Large and XL are helpful too. I'll edit this post with the values for all to quickly reference.

Small:
Medium: 82cm
Large: 86cm
X-Large:

I've searched the forums and found many posts about height to frame size but I didn't see anything for "RAD". In basic terms, the "RAD" measurement is the distance from the center of the BB to the center intersection of the grips. This part in a Joy of Bike video explains it: This video will also show you how to measure your own RAD to see how it compares to your bike's RAD.

 

[Jfive]

Added the large RAD measurement, provided by Phoenix in this thread

 

[balticmoe]

@Minute 8 he messured 830mm for the medium Rise:

I‘m 182 cm tall and have an inseam length of 82 cm. Every bike shop is telling me to pick the large Rise, but without the possibility testing M and L back to back I‘m really torn about the frame size…

 

[neilo]

If it helps, I followed the RAD approach when I bought my Rise, and I sized down from XL to L and I am very happy. I am 191cm. The shop was quite surprised and triple checked with me when I placed the order, since I'm way into the XL range on the Orbea chart. Fit is much better than my previous (2020 Fuel EX 8 XL). An XL Rise would have had a longer RAD than the Trek.

I thought the L would be a touch small, so I bought a 60mm stem before the bike was delivered, in anticipation of needing it. But I haven't felt the need to try it.

 

[Jfive]

@Minute 8 he messured 830mm for the medium Rise:

I‘m 182 cm tall and have an inseam length of 82 cm. Every bike shop is telling me to pick the large Rise, but without the possibility testing M and L back to back I‘m really torn about the frame size…

good find! Seems like he isn’t running stock stem and handle bars but it should be very close to stock.
I ordered a Medium and will measure it once it arrives to provide another data point for stock H30.

 

[Jfive]

If it helps, I followed the RAD approach when I bought my Rise, and I sized down from XL to L and I am very happy. I am 191cm. The shop was quite surprised and triple checked with me when I placed the order, since I'm way into the XL range on the Orbea chart. Fit is much better than my previous (2020 Fuel EX 8 XL). An XL Rise would have had a longer RAD than the Trek.

I thought the L would be a touch small, so I bought a 60mm stem before the bike was delivered, in anticipation of needing it. But I haven't felt the need to try it.

Good to hear it’s working out well for you. I hope going with the medium instead of the large is right for me too.

 

[ilostmypassword]

Interesting video. Sorry to hijack with another bike brand

I'm really struggling with size for my first eBike the 2020 Trance X E+1 . I'm 5' 5" but have a 32" in seam. On the size chart I'm a small- but 32" in seam suggest a medium. The shop naturally suggested a medium but from memory, having a smaller bike makes it more ridable when it gets technical.

Worst case I can just add a 50mm stem and push the seat back to make up for the 3.3 cm reach difference between the sizes. Geez I really do find sizing the hardest part of shopping a bike.

Edit: Just did the RAD math and;

167.64mm x 2.5 = 41cm reach
167.64mm x 2.45 = 41.7 reach

Small Trance X E+1 reach is 43.9 cm so it should be fine. Maybe even a shorter stem is in order

Thanks for sharing these videos guys. Super appreciated.

 

[soundwave]

189cm here with XL. Can’t even think about riding an L

 

[Longfellow78]

@Minute 8 he messured 830mm for the medium Rise:

I‘m 182 cm tall and have an inseam length of 82 cm. Every bike shop is telling me to pick the large Rise, but without the possibility testing M and L back to back I‘m really torn about the frame size…

I would be shocked if you didn't find the M too small tbh. I fit an M and I am 166cm.

 

[Shjay]

@Minute 8 he messured 830mm for the medium Rise:

I‘m 182 cm tall and have an inseam length of 82 cm. Every bike shop is telling me to pick the large Rise, but without the possibility testing M and L back to back I‘m really torn about the frame size…

I am same height with shorter legs & on a large with 210mm dropper medium would be tiny!

 

[balticmoe]

I would be shocked if you didn't find the M too small tbh. I fit an M and I am 166cm.

I am same height with shorter legs & on a large with 210mm dropper medium would be tiny!

Thank you for the answers. I understand the points completely.

I would like to have an agile bike and have concerns about the length of the seat post/seat tube.

@Shjay Do you have a picture of you sitting and/or standing on the bike?

Unfortunately, the next test opportunity is 6 hours away from me...

 

[soundwave]

Maybe there are similar bikes with similar geo near you for testing? Orbea Laufey is pretty close, Occam probably as well. Yeti Arc and Banshee Paradox as well. I would trust traditional geo recommendations over these more exotic ones.

 

[Longfellow78]

The rad measurements by the original person who invented it, Lee McCormack or something, which is height in cm*4.47, is totally wrong and outdated for modern geometry, expecially as shorter bikes with higher bars have a longer RAD but smaller reach. By his calculations you need to be 6ft for a RAD of 830 which is a medium rise, which is clearly way out. I would ignore this measure personally and just go by height, with a slightly smaller size for same height with women due to longer legs and shorter reach.

 

[Shjay]

Thank you for the answers. I understand the points completely.

I would like to have an agile bike and have concerns about the length of the seat post/seat tube.

@Shjay Do you have a picture of you sitting and/or standing on the bike?
Sorry no photos of me on the bike, previous 3 bikes all longer reach than the Rise. It’s still an agile bike as the wheelbase isn’t too long
Unfortunately, the next test opportunity is 6 hours away from me...

 

[balticmoe]

The rad measurements by the original person who invented it, Lee McCormack or something, which is height in cm*4.47, is totally wrong and outdated for modern geometry, expecially as shorter bikes with higher bars have a longer RAD but smaller reach. By his calculations you need to be 6ft for a RAD of 830 which is a medium rise, which is clearly way out. I would ignore this measure personally and just go by height, with a slightly smaller size for same height with women due to longer legs and shorter reach.

The approach or the idea was/is quite interesting because it is based on another relatively easy to determine variable.

But it is precisely this factor of 4.47 that creates some uncertainty, because it is again questionable how generally valid it is. I am not in a position to judge this. However, it is also difficult to compare only reach and stack...

@Shjay
For me it's the other way round. My last bike had a reach of 450mm, so it was shorter than the Rise in L. But the seat angle wasn't as steep either.

I'm slowly getting used to the L size

 

[neilo]

The rad measurements by the original person who invented it, Lee McCormack or something, which is height in cm*4.47, is totally wrong and outdated for modern geometry, expecially as shorter bikes with higher bars have a longer RAD but smaller reach. By his calculations you need to be 6ft for a RAD of 830 which is a medium rise, which is clearly way out. I would ignore this measure personally and just go by height, with a slightly smaller size for same height with women due to longer legs and shorter reach.

If you watch all of Lee's videos on the topic, you'll see that the height x 4.47 formula is a short-cut. It doesn't take into account your individual ape index (arm length vs height). The "correct" way to determine the "right" RAD for you is a measurement of centre of clenched fist to ground, wearing your riding shoes, in your riding stance (feet spread as if on the pedals). The measurement is intentionally geo-independent - the point being that something like a steeper STA or slacker HTA isn't changing the distance between the pedals and your hands (which are the only contact points when descending). If you care about seated reach (how much room you have when sitting on the saddle), then the RAD measurement isn't going to help you. Lee's point is that we should mostly ignore seated reach though, since as mtb'ers we're not sitting down when it matters.

I happen to have enough seated room on a Large Rise even at 191cm, I think because (a) my legs are relatively short for my height and (b) I don't mind a relatively upright seated position. And when I'm active on the bike (e.g. row, anti-row over a jump, or pumping a feature), the pedals to bars distance feels more right than my old XL Trek.

 

[Jfive]

I measured 82cm for RAD on my stock size Medium Rise H30 and have updated my original post. If anyone has the measurements for their Small or XL Rise, please post it.

 

[John_A]

If you watch all of Lee's videos on the topic, you'll see that the height x 4.47 formula is a short-cut. It doesn't take into account your individual ape index (arm length vs height). The "correct" way to determine the "right" RAD for you is a measurement of centre of clenched fist to ground, wearing your riding shoes, in your riding stance (feet spread as if on the pedals). The measurement is intentionally geo-independent - the point being that something like a steeper STA or slacker HTA isn't changing the distance between the pedals and your hands (which are the only contact points when descending). If you care about seated reach (how much room you have when sitting on the saddle), then the RAD measurement isn't going to help you. Lee's point is that we should mostly ignore seated reach though, since as mtb'ers we're not sitting down when it matters.

I happen to have enough seated room on a Large Rise even at 191cm, I think because (a) my legs are relatively short for my height and (b) I don't mind a relatively upright seated position. And when I'm active on the bike (e.g. row, anti-row over a jump, or pumping a feature), the pedals to bars distance feels more right than my old XL Trek.

Sorry to resurrect an old thread but just been thinking about RAD as I’m thinking about getting a new bike. If The "correct" way to determine the "right" RAD for you is a measurement of centre of clenched fist to ground, surely this means the longer your arms the shorter your RAD is or am I missing something?

 

[dthree]

Sorry to resurrect an old thread but just been thinking about RAD as I’m thinking about getting a new bike. If The "correct" way to determine the "right" RAD for you is a measurement of centre of clenched fist to ground, surely this means the longer your arms the shorter your RAD is or am I missing something?

Arm length does factor into RAD, but so does leg length and torso length. Measuring fists to the ground is more accurate than height * 4.47 or whatever because it’s measuring just the distance from hands to feet in riding position which corresponds closest to the bottom bracket to handlebars distance. I estimated this when shopping when I couldn’t measure a bike in person by plugging the stack and reach into a right triangle calculator.

 

[John_A]

Arm length does factor into RAD, but so does leg length and torso length. Measuring fists to the ground is more accurate than height * 4.47 or whatever because it’s measuring just the distance from hands to feet in riding position which corresponds closest to the bottom bracket to handlebars distance. I estimated this when shopping when I couldn’t measure a bike in person by plugging the stack and reach into a right triangle calculator.

Having measured by RAD using the fists to ground method I get 85cm, although my height is only 180cm, my Large Rise seems a good fit, but maybe a little bit small if anything Also have a Whyte hardtail in medium with a very similar RAD to the large Rise. Tried a large Whyte hardtail with only a slightly longer reach than the Rise, but a much slacker seat angle and couldnt get on with the seated riding position. Seems Whyte idea of an ideal fit for someone 180cm is quite different to Orbeas. Which is a shame, as I love Whyte bikes, but need to run a silly long post on a medium frame.

What's your thoughts on RAD? Plenty of people seem to ride well and size up, in the market for a new bike and don't know whether to stick with what I know or try something new/bigger

 

[dthree]

Having measured by RAD using the fists to ground method I get 85cm, although my height is only 180cm, my Large Rise seems a good fit, but maybe a little bit small if anything Also have a Whyte hardtail in medium with a very similar RAD to the large Rise. Tried a large Whyte hardtail with only a slightly longer reach than the Rise, but a much slacker seat angle and couldnt get on with the seated riding position. Seems Whyte idea of an ideal fit for someone 180cm is quite different to Orbeas. Which is a shame, as I love Whyte bikes, but need to run a silly long post on a medium frame.

What's your thoughts on RAD? Plenty of people seem to ride well and size up, in the market for a new bike and don't know whether to stick with what I know or try something new/bigger

Well, take this with a grain of salt because I don't think I've ridden enough different bikes to have a good feel for real subtle sizing differences.
To me, stack and reach don't seem like they correspond easily to a body dimension, but RAD gave me an additional dimension that helped me determine that I fit better on a S Rise than a M. I wasn't sure because I'm in a medium according to their height chart, but I have shorter legs for my height, and that affects both RAD and effective seatpost length. I'm not even sure I could clamp the 150mm dropper post low enough on the M to reach the pedals correctly when its raised. So far, 600+ km in, I'm pretty happy with the sizing.