I noticed 2 small changes you should try. First when you set up to measure your RAD your feet should be pedal distance apart. This will lower your measurement slightly but get you much more exact. Then, when you place your string on the handlebars it only is a refence line. You actually have to extend your measurement just past the string to an imaginary point that is the center of the bars at the points you attached your string. You can see when you laid on the ground that your arms were slightly bent. This would indicate you have a little bit of length still on the bike. That last 10mm is butter once you get it. Makes the bike so much more fun to ride.
Good points to bring up. Your stance can make a difference in measurement. I have adjusted where I put the string to try to make it go through the centre of the handlebars. Creating an exact measurement with so many variables is very hard to create. I'm pretty confident I am within 10mm of my neutral RAD. I play with slightly longer or shorter depending on the bike based on how I ride it.
Thanks for this man! I have been wondering about the Spread concept alot, but you made me understand it. How to measure and all! I am 180 cm and always between a M/L bike. But a new bike I am thinking of has Spread very near to my value, in size L. So now I finally can sleep, I know what size to buy! :)
So happy my video helped. That is the exact reason I love this concept. There will be way less trial and error with your stem and spacers once you get the bike.
Lee and also you said that the string from the BB up to the imaginary line 1cm below the bars string the should run parallel to the frame, but at 3:11 i can see is not much parallel to the diagonal frame tube. I'm asking because i did the same, and if i go perfectly parallel, all goes to the feeling that the frame is big...
You can use this for commuters and other non mountain bikes. It gets you a good position. Having said that, For bikes you sit and pedal on more than ride downhill, a more traditional bike fit theory where you focus on the position of your saddle in relation to the handlebars will get better results.
Although this video is a bit old, can anyone shed some light on this for me? I'm 184cm tall, with a 89cm inseam and 194cm wingspan. In other words... long legs and long arms. I currently ride a Trek Top Fuel size L. However, when I bought the bike, it felt a bit small and I didn't have much control over the bike's steering. I put on a 70mm stem and was finally able to ride although with the 70mm stem I feel like I don't have full control over the steering. I usually ride on very technical trails with lots of roots, rocks, drops and some jumps. I'm thinking about getting a Trek Slash size L. The Slash has a reach of 486cm and stack of 635. I measured my RAD and I'm not sure if I have 860 (measured with my hands down) or 890 (measured using a handlebar) and my ideal reach would be 184*2.55 = 469mm. With my Top Fuel L + 70mm stem + 3 spacers (10mm each), the bike's RAD is 870 (very close to my RAD 860 or 890) and the real reach is 495mm. The Slash XL has a reach of 516mm and a stack of 658mm. I believe that with this measurement, the RAD should be around 880/890. However, its the reach of 516mm is WAY outside the my "ideal" (469mm). Should I buy the Slash in size L or XL? Thanks
@diegutpf have you done one of the on bike checks I show in the video? This will be a good check to see what RAD will be most accurate. I have washed myself so many times and get a range of measurements, mostly from an error on my set up to measure. From the sounds of it you will be able to get either the L or XL close to your RAD. The L will be a shorter/higher fit. The XL will be longer/lower. If you can make either fit without something excessive like a 70mm stem you can choose the size based on how you want it to ride. L will be more agile. XL will be more stable at high speed. Hope this helps
Problem: When you measure standing, your body is straight. When you measure lying on your back, your body is not straight. You will get a different measurement in cm.
You are correct! This is one thing of many which can alter your measurement slightly. As I use this method more and more I find it more important to get close to neutral then make adjustments to make your bike fit comfortable and ride as it is intended. Focusing on a perfectly neutral RAD is fleeting since it is hard to get a truly accurate measurement since everything from your stance, the thickness of the sole of your shoe changes what you will measure, pedal thickness, handlebar sweep etc... effects it in some way.
This approach works great. If your bike is say 1+-cm short, you notice it and can correct with steel, space or riser adjustments.
I noticed 2 small changes you should try. First when you set up to measure your RAD your feet should be pedal distance apart. This will lower your measurement slightly but get you much more exact. Then, when you place your string on the handlebars it only is a refence line. You actually have to extend your measurement just past the string to an imaginary point that is the center of the bars at the points you attached your string. You can see when you laid on the ground that your arms were slightly bent. This would indicate you have a little bit of length still on the bike. That last 10mm is butter once you get it. Makes the bike so much more fun to ride.
Good points to bring up. Your stance can make a difference in measurement.
I have adjusted where I put the string to try to make it go through the centre of the handlebars.
Creating an exact measurement with so many variables is very hard to create.
I'm pretty confident I am within 10mm of my neutral RAD. I play with slightly longer or shorter depending on the bike based on how I ride it.
👏🏿👏🏽👏🏻Great job breaking down RAD measurements & how to get em👏🏻👏🏽👏🏿
Thank you!
Thanks for this man! I have been wondering about the Spread concept alot, but you made me understand it. How to measure and all! I am 180 cm and always between a M/L bike. But a new bike I am thinking of has Spread very near to my value, in size L. So now I finally can sleep, I know what size to buy! :)
So happy my video helped. That is the exact reason I love this concept. There will be way less trial and error with your stem and spacers once you get the bike.
I think you described RAD better than Joy of Bike did!
Awesome job!
Thanks Craig!
Yep. EXCELLENT EXCELLENT EXCELLENT EXCELLENT VIDEO!
Thank you!
Lee and also you said that the string from the BB up to the imaginary line 1cm below the bars string the should run parallel to the frame, but at 3:11 i can see is not much parallel to the diagonal frame tube. I'm asking because i did the same, and if i go perfectly parallel, all goes to the feeling that the frame is big...
The string should go parallel to the frame when you look at it from above. It will not be parallel to the diagonal downtube from a side view.
@@alpinemtbtraining that was my mayor doubt, thanks for clarify!
Can you also apply this if your MTB bike purpose is for commuting or mid to long distance travel?
You can use this for commuters and other non mountain bikes. It gets you a good position.
Having said that, For bikes you sit and pedal on more than ride downhill, a more traditional bike fit theory where you focus on the position of your saddle in relation to the handlebars will get better results.
great video 👌
Thank you!
Although this video is a bit old, can anyone shed some light on this for me?
I'm 184cm tall, with a 89cm inseam and 194cm wingspan. In other words... long legs and long arms.
I currently ride a Trek Top Fuel size L. However, when I bought the bike, it felt a bit small and I didn't have much control over the bike's steering.
I put on a 70mm stem and was finally able to ride although with the 70mm stem I feel like I don't have full control over the steering.
I usually ride on very technical trails with lots of roots, rocks, drops and some jumps.
I'm thinking about getting a Trek Slash size L.
The Slash has a reach of 486cm and stack of 635.
I measured my RAD and I'm not sure if I have 860 (measured with my hands down) or 890 (measured using a handlebar) and my ideal reach would be 184*2.55 = 469mm.
With my Top Fuel L + 70mm stem + 3 spacers (10mm each), the bike's RAD is 870 (very close to my RAD 860 or 890) and the real reach is 495mm.
The Slash XL has a reach of 516mm and a stack of 658mm.
I believe that with this measurement, the RAD should be around 880/890.
However, its the reach of 516mm is WAY outside the my "ideal" (469mm).
Should I buy the Slash in size L or XL? Thanks
@diegutpf have you done one of the on bike checks I show in the video? This will be a good check to see what RAD will be most accurate. I have washed myself so many times and get a range of measurements, mostly from an error on my set up to measure. From the sounds of it you will be able to get either the L or XL close to your RAD. The L will be a shorter/higher fit. The XL will be longer/lower. If you can make either fit without something excessive like a 70mm stem you can choose the size based on how you want it to ride. L will be more agile. XL will be more stable at high speed. Hope this helps
Why am I not getting any sound? 1
Never mind lol
What frame brand is it?
It is an RSD (Rubber Side Down) Middlechild
Problem: When you measure standing, your body is straight. When you measure lying on your back, your body is not straight. You will get a different measurement in cm.
You are correct! This is one thing of many which can alter your measurement slightly. As I use this method more and more I find it more important to get close to neutral then make adjustments to make your bike fit comfortable and ride as it is intended. Focusing on a perfectly neutral RAD is fleeting since it is hard to get a truly accurate measurement since everything from your stance, the thickness of the sole of your shoe changes what you will measure, pedal thickness, handlebar sweep etc... effects it in some way.