ak-tux
Zen MBB Master
May be I should have started a new thread on fitting but anyway here goes a long post:
Another Update on my S40:
So, I changed the crankset and chainring as earlier shared and then got slightly bigger shoes.
First the Crankset:
The 170mm cranks with a 48T chainring works well with the stock 11-42 cassette for grades upto short sections of about 10% . Offcourse this is not for a loaded cycling. I found that it feels good becuase I was well adapted to 170mm cranks on my homemade bicycle. I really like it. I also got a Sunrace 11 speed Cassette (CSMX8 11-46) to try for steeper climbs and it fits beautifully!
The Shoes, cleats, Hotfoot, Recumbutt, fit issues and performance
First, a little disclaimer this issues were there even before the S40. I had battled them on my homemade for a while. Thankfully, the beautiful S40 is very adjustable!
I personally think that one challenging aspect of recumbent bicycles is gettting a good reference for optimal fit. Upright bicycles have a well understood fitting procedure. The cruzbikes/MBB front triangle is similar to an upright bicycle. However gettting the equivalent of the optimal "seat height" is not as straight forward due to the shape of the seat and the nature of the seatpad. The pad compresses under pedalling loads and eventually "sets" and changes the actual seat to crank distance. For this reason , I believe a thick and squishy seatpad like the stock one is actually not good IMHO. I replaced the inner form with a yoga mat form. Thickness is only about 20mm yet still very comfortable.
The S40 is significanlty lighter than my homemade one and only about 1.3Kgs heavier than my roadbike. Yet I could not match my road bike on climbs with 2.5% - 10% grades (higher grades just favours the roadbike) that I have repeatedly measured. Looking at the picture above, I still I could not see why I could not match my roadbike on moderate climbs. By this point I was now fully convinced it's something wrong with my fit.
Fit Solution
So I got bigger shoes and combined with the 170mm cranks came fitting issues . I also started experiencing mild recumbutt on my right leg. This was not there the first few weeks after I got the S40 (but was accassionally there on my homemade bike). I was therfore convinced that definitley something was wrong with my fit.
I had to do some research. I believe I discovered two or three things:
I have strava segments that I have recorded using my roadbike and then my recumbents. Several times over a few months. In the past, try as I may, I could not match the roadbike. I just couldn't understand why. The segment in question is 1.5Km long at an average of 3.6% max at about 8.9% or 9% . There is a 400m section that I was always aboout 12 to 20 secs slower than my road bike. After the above changes my best S40 effort was now within only 4seconds of my average DF climbing time. I will repeat again for a couple of weeks to be sure.
Things are looking up! I have a good feeling about this. I hope this helps other S40 owners out there.
More next time.
Koros.
Ref:
Midfoot Cleat reference Videos:
Another Update on my S40:
So, I changed the crankset and chainring as earlier shared and then got slightly bigger shoes.
First the Crankset:
The 170mm cranks with a 48T chainring works well with the stock 11-42 cassette for grades upto short sections of about 10% . Offcourse this is not for a loaded cycling. I found that it feels good becuase I was well adapted to 170mm cranks on my homemade bicycle. I really like it. I also got a Sunrace 11 speed Cassette (CSMX8 11-46) to try for steeper climbs and it fits beautifully!
The Shoes, cleats, Hotfoot, Recumbutt, fit issues and performance
First, a little disclaimer this issues were there even before the S40. I had battled them on my homemade for a while. Thankfully, the beautiful S40 is very adjustable!
I personally think that one challenging aspect of recumbent bicycles is gettting a good reference for optimal fit. Upright bicycles have a well understood fitting procedure. The cruzbikes/MBB front triangle is similar to an upright bicycle. However gettting the equivalent of the optimal "seat height" is not as straight forward due to the shape of the seat and the nature of the seatpad. The pad compresses under pedalling loads and eventually "sets" and changes the actual seat to crank distance. For this reason , I believe a thick and squishy seatpad like the stock one is actually not good IMHO. I replaced the inner form with a yoga mat form. Thickness is only about 20mm yet still very comfortable.
The S40 is significanlty lighter than my homemade one and only about 1.3Kgs heavier than my roadbike. Yet I could not match my road bike on climbs with 2.5% - 10% grades (higher grades just favours the roadbike) that I have repeatedly measured. Looking at the picture above, I still I could not see why I could not match my roadbike on moderate climbs. By this point I was now fully convinced it's something wrong with my fit.
Fit Solution
So I got bigger shoes and combined with the 170mm cranks came fitting issues . I also started experiencing mild recumbutt on my right leg. This was not there the first few weeks after I got the S40 (but was accassionally there on my homemade bike). I was therfore convinced that definitley something was wrong with my fit.
I had to do some research. I believe I discovered two or three things:
1. The recumbutt is not necessarly always a result of the seat angle especially if it tends to occur on one side. I'am now convinced, the body shifts the weight to the dominant leg on one side while trying to compensate for the discomfort due to either over reaching/over extension of the legs or improper cleat positions. I'am fairly flexible and I think I did not realise that the BB was too far. I was over extending my legs and overreaching my handlebars.
2. My hotfoot solution required that
2. My hotfoot solution required that
a.) the shoes to be spacious
b.) the cleats to move back behind the ball of my foot. I found a bike fitter on youtube who recommended that the best place is about 10 to 15mm behind the ball of the foot. This stabilises the foot, reduces the load on the calf muscles and reduces the likelihood of numbness.
c.) Consequently due to (b) above, my effective leg length became shorter and I had to also adjust the boom to bring the bottom bracket closer. I did it in steps of 5mm. (I love the way the S40 boom is marked out! )
b.) the cleats to move back behind the ball of my foot. I found a bike fitter on youtube who recommended that the best place is about 10 to 15mm behind the ball of the foot. This stabilises the foot, reduces the load on the calf muscles and reduces the likelihood of numbness.
c.) Consequently due to (b) above, my effective leg length became shorter and I had to also adjust the boom to bring the bottom bracket closer. I did it in steps of 5mm. (I love the way the S40 boom is marked out! )
3. Relaxed and well supported upper body: I modified by neckrest using a PVC pipe to resemble the Cruzbike suspension headrest in order to improve the support to my neck and relax my upper body.
I have strava segments that I have recorded using my roadbike and then my recumbents. Several times over a few months. In the past, try as I may, I could not match the roadbike. I just couldn't understand why. The segment in question is 1.5Km long at an average of 3.6% max at about 8.9% or 9% . There is a 400m section that I was always aboout 12 to 20 secs slower than my road bike. After the above changes my best S40 effort was now within only 4seconds of my average DF climbing time. I will repeat again for a couple of weeks to be sure.
Things are looking up! I have a good feeling about this. I hope this helps other S40 owners out there.
More next time.
Koros.
Ref:
Midfoot Cleat reference Videos:
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