Fitting new bike to existing bike
08-29-18, 08:01 AM
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Fitting new bike to existing bike
I have a custom geometry road bike that fits me like a glove. It’s a tall height (head tube plus spacers) and a short length/reach (relative to off-the-shelf bikes), as I was after comfort. Again, it’s perfect for me (been riding it 10 years).
I’ve bought several other bikes since this one and I usually fit the new bike to the old one (best as possible) by trying to replicate the measurements (below), with some minor compromises where necessary.
I have a new bike, meant for gravel/bikepacking, and after 3 rides it feels great, but I think the reach could be a little longer (feels slightly cramped, and my neck is telling me so after 2+ hr rides; shorter rides are excellent). I think I know what to do, but wanted to share some numbers below along with my solution.
These #’s are the gravel bike in comparison to the road bike. I’m not going to detail how I took the measurements, i.e., center-to-center, but I was consistent between the bikes.
Saddle height – 5mm higher (same saddle, but gravel bike has SPD with mtn shoes while road bike has SPD-SL with road shoes. Also, the gravel bike has 170mm crankarm versus 172.5 on the road bike). I’m not sure how this translates, but more on this below under ‘Saddle setback’.
Reach – 10mm shorter. I think I need to correct this by using a longer stem. See end for my idea as other factors to consider.
Saddle setback – 5mm longer from BB. What’s interesting here, is that when I drop a plumb line from my knee to the pedal spindle, my knee is ‘behind’ the axle but a little bit. On the road bike it’s directly over.
Saddle drop (to bars) – 5mm higher.
How I’m thinking to solve this…switch from the 100mm stem to a 115mm stem. I have a Deda stem on its way, and it wasn’t expensive. I’m thinking that the 115mm will add the reach I need, and at the same time I will move the saddle 5mm forward, to hopefully get my knee over the spindle. Also, the longer stem with its 6 or 7 degree rise will help with the saddle drop.
Does this make sense? Am I missing something?
P.S. I will likely be doing a bit fitting in any case, but can’t go for at least two weeks…so this was my temporary solution. However, if I do this and it feels amazing, then I may skip the fitting…for now.
I’ve bought several other bikes since this one and I usually fit the new bike to the old one (best as possible) by trying to replicate the measurements (below), with some minor compromises where necessary.
I have a new bike, meant for gravel/bikepacking, and after 3 rides it feels great, but I think the reach could be a little longer (feels slightly cramped, and my neck is telling me so after 2+ hr rides; shorter rides are excellent). I think I know what to do, but wanted to share some numbers below along with my solution.
These #’s are the gravel bike in comparison to the road bike. I’m not going to detail how I took the measurements, i.e., center-to-center, but I was consistent between the bikes.
Saddle height – 5mm higher (same saddle, but gravel bike has SPD with mtn shoes while road bike has SPD-SL with road shoes. Also, the gravel bike has 170mm crankarm versus 172.5 on the road bike). I’m not sure how this translates, but more on this below under ‘Saddle setback’.
Reach – 10mm shorter. I think I need to correct this by using a longer stem. See end for my idea as other factors to consider.
Saddle setback – 5mm longer from BB. What’s interesting here, is that when I drop a plumb line from my knee to the pedal spindle, my knee is ‘behind’ the axle but a little bit. On the road bike it’s directly over.
Saddle drop (to bars) – 5mm higher.
How I’m thinking to solve this…switch from the 100mm stem to a 115mm stem. I have a Deda stem on its way, and it wasn’t expensive. I’m thinking that the 115mm will add the reach I need, and at the same time I will move the saddle 5mm forward, to hopefully get my knee over the spindle. Also, the longer stem with its 6 or 7 degree rise will help with the saddle drop.
Does this make sense? Am I missing something?
P.S. I will likely be doing a bit fitting in any case, but can’t go for at least two weeks…so this was my temporary solution. However, if I do this and it feels amazing, then I may skip the fitting…for now.
09-02-18, 05:17 PM
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Its not clear to me what your overall goal is, whether you are mimicking your road bike exactly or whether your gravel setup will be done so that the drops will be the main position versus the hoods being the main position on your road bike...?
If its the latter, I would think that you want a higher rising stem to move the main gravel position closer to the main road position. A 5mm stem increase at 7deg is only 0.6mm increase in stack.
If its the latter, I would think that you want a higher rising stem to move the main gravel position closer to the main road position. A 5mm stem increase at 7deg is only 0.6mm increase in stack.
09-02-18, 07:38 PM
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Its not clear to me what your overall goal is, whether you are mimicking your road bike exactly or whether your gravel setup will be done so that the drops will be the main position versus the hoods being the main position on your road bike...?
If its the latter, I would think that you want a higher rising stem to move the main gravel position closer to the main road position. A 5mm stem increase at 7deg is only 0.6mm increase in stack.
If its the latter, I would think that you want a higher rising stem to move the main gravel position closer to the main road position. A 5mm stem increase at 7deg is only 0.6mm increase in stack.
09-05-18, 08:06 AM
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Frankly, I don’t read this Forum, but I have a problem and would appreciate any comments. Instead of starting a new thread, I think it fits here. 
Just this moring I posted to this thread on the Fifty-Plus Forum, “So how do you justify another bike in the stable?”
Just this moring I posted to this thread on the Fifty-Plus Forum, “So how do you justify another bike in the stable?”
This year however has been a bust because this winter I developed a weakness in my neck muscles supporting my head upright (perhaps due to a two month unavoidable layoff) on my previously well-fitted bikes.
I had a subsequent fitting on both, with some handlebar adjustments. I recently got an exercise consultation for neck, shoulder and core muscles, and was given an exercise routine, that takes a big chunk of 50 minutes to perform. Exercise may fix it, but that’s a long-term solution.
All these remedies have barely allow me to ride my minimum 14 mile one-way commute with slight discomfort near the end. By this time of the year I'm doing weekly 50-60 mile rides easily, and even training for a Century. Just yesterday, I rented a hybrid style bike with flat handlebars, and was comfortable on the commute, even with a moderately heavy backpack
So now I’m giving in to the idea of a flat bar bike. I’m in a quandary if I should replace the drop bars on my aluminum beater (with endurance style geometry) with flat bars, see if I can buy this relatively cheap hybrid since it seems to work, or buy a new quality hybrid to my specifications. The Diverge is already set up as a nice all-weather commuter (see photo). I’m going to my trusted LBS on Saturday to make a decision.
I had a subsequent fitting on both, with some handlebar adjustments. I recently got an exercise consultation for neck, shoulder and core muscles, and was given an exercise routine, that takes a big chunk of 50 minutes to perform. Exercise may fix it, but that’s a long-term solution.
All these remedies have barely allow me to ride my minimum 14 mile one-way commute with slight discomfort near the end. By this time of the year I'm doing weekly 50-60 mile rides easily, and even training for a Century. Just yesterday, I rented a hybrid style bike with flat handlebars, and was comfortable on the commute, even with a moderately heavy backpack
So now I’m giving in to the idea of a flat bar bike. I’m in a quandary if I should replace the drop bars on my aluminum beater (with endurance style geometry) with flat bars, see if I can buy this relatively cheap hybrid since it seems to work, or buy a new quality hybrid to my specifications. The Diverge is already set up as a nice all-weather commuter (see photo). I’m going to my trusted LBS on Saturday to make a decision.
09-05-18, 09:36 AM
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Likely for different reasons, but I was in the same boat (neck and shoulder issues) a few years ago. I have a custom geometry road bike and it’s continued to feel great even when I was at my worst, but at times the neck would still hurt. That same bike is back to perfect 99% of the time.
i have a series of stretches I do daily, and have for about three years. In the last year I’ve added a couple stretches that target some muscles that were still sore or triggering soreness elsewhere. My RMT recommended these...and the previous physio, chiro and other RMTs did not, even though these pains were there (no one is perfect). I feel like I now have the right series of stretches in my quiver. When riding, I do some of these every 1-2 hours, makes a huge difference on longer rides and only takes five minutes.
All I can say is good luck and keep positive.
i have a series of stretches I do daily, and have for about three years. In the last year I’ve added a couple stretches that target some muscles that were still sore or triggering soreness elsewhere. My RMT recommended these...and the previous physio, chiro and other RMTs did not, even though these pains were there (no one is perfect). I feel like I now have the right series of stretches in my quiver. When riding, I do some of these every 1-2 hours, makes a huge difference on longer rides and only takes five minutes.
All I can say is good luck and keep positive.
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