What mods have you done to lighten your Ebike

Alaskan

Well-Known Member
@Timpo raises some really valid points about rotational weight and the difference between weight near the center of the wheel versus weight at the outer perimeter. Toward that end I find that carbon rims shave very little weight as compared with good alloy rims (commonly estimated at $5/gram, especially on a cost weighted basis. Obviously going tubeless or using Tubolito light weight tubes save far more weight per dollar, around 70-80 grams for a $35 tubolito grams. In fact Tubolitos save as much, if no slightly more, then tubless when considering the weigh of sealant required, especially in wider tires.

An Item I am installing on my Topstone Neo Carbon 3 that will be adding56 grams but should more than make up for it in performance is an Onyx rear hub. Trek put an Onyx hub on my Allant 9.9s to replace the faulty Shimano hub that it came with. I am now forever spoiled and want one on every bike I own.

Onyx hubs use a sprag clutch mechanism instead of a traditional gear & sprung pawl. Not only to they offer instant engagement (no lag when resuming pedaling) but the also completely disengage when pedaling ceases...the clutch mechanism offers zero resistance. They also use ceramic bearings which are significantly smoother and faster rolling than metal ball bearings. As the added weight is right next to the axle, the additional 100-150 grams will not be significant rotational weight (it is added unspring weight that can make a difference on a full suspension bike however). So while they add grams, they should increase speed through better bearings and complete disengagement of the clutch mechanism. The instant engagement adds a real advantage while climbing steep gravel trails too. Oh and another distinction of Onyx hubs is they go completely silent when coasting, no buzz or whirr associated with a gear spinning by sprung pawls. Oh and they can be disassembled for service in less than two minutes. They are costly but are a terrific product that enhances the ride experience any bike and made in Minnesota


 
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Gionnirocket

Well-Known Member
Region
USA
City
Y. O.
@Timpo raises some really valid points about rotational weight and the difference between weight near the center of the wheel versus weight at the outer perimeter. Toward that end I find that carbon rims shave very little weight as compared with good alloy rims (commonly estimated at $5/gram, especially on a cost weighted basis. Obviously going tubeless or using Tubolito light weight tubes save far more weight per dollar, around 70-80 grams for a $35 tubolito grams. In fact Tubolitos save as much, if no slightly more, then tubless when considering the weigh of sealant required, especially in wider tires.

An Item I am installing on my Topstone Neo Carbon 3 that will be adding56 grams but should more than make up for it in performance is an Onyx rear hub. Trek put an Onyx hub on my Allant 9.9s to replace the faulty Shimano hub that it came with. I am now forever spoiled and want one on every bike I own.

Onyx hubs use a sprag clutch mechanism instead of a traditional gear & sprung pawl. Not only to they offer instant engagement (no lag when resuming pedaling) but the also completely disengage when pedaling ceases...the clutch mechanism offers zero resistance. They also use ceramic bearings which are significantly smoother and faster rolling than metal ball bearings. As the added weight is right next to the axle, the additional 100-150 grams will not be significant rotational weight (it is added unspring weight that can make a difference on a full suspension bike however). So while they add grams, they should increase speed through better bearings and complete disengagement of the clutch mechanism. The instant engagement adds a real advantage while climbing steep gravel trails too. Oh and another distinction of Onyx hubs is they go completely silent when coasting, no buzz or whirr associated with a gear spinning by sprung pawls. Oh and they can be disassembled for service in less than two minutes. They are costly but are a terrific product that enhances the ride experience any bike and made in Minnesota


Yeah but 56g...I don't know, seems like a lot.
 

fooferdoggie

Well-Known Member
@Timpo

Onyx hubs use a sprag clutch mechanism instead of a traditional gear & sprung pawl. Not only to they offer instant engagement (no lag when resuming pedaling) but the also completely disengage when pedaling ceases...the clutch mechanism offers zero resistance. They also use ceramic bearings which are significantly smoother and faster rolling than metal ball bearings. As the added weight is right next to the axle, the additional 100-150 grams will not be significant rotational weight (it is added unspring weight that can make a difference on a full suspension bike however).
little expensive for me. Not sure on the ceramic bearings in rainy conditions. II will stick with my dt swiss hubs hey only 250.00 each (G)
 

Alaskan

Well-Known Member
little expensive for me. Not sure on the ceramic bearings in rainy conditions. II will stick with my dt swiss hubs hey only 250.00 each (G)
How could steel bearing possibly be better than ceramic bearing in the presence of water. Last I checked steel rusts and ceramic does not. Yes the trade off is cost and weight. Having ridden an Onyx on my Allant, for me the plusses far outweigh the minuses. YMMV
 
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fooferdoggie

Well-Known Member
How could steep bearing possibly be better than ceramic bearing in the presence of water. Last I checked steel rusts and ceramic does not. Yes the trade off is cost and weight. Having ridden an Onyx on my Allant, for me the plusses far outweigh the minuses. YMMV
have you tried other high end hubs? I doubt most people could tell the difference. dirt and stuff in ceramic bearings is worse then in bearings with grease. I mean on a high end race bike maybe but on a e bike? you could never tell the difference in rolling resistance and they add a huge cost to the hub. the money spent on much better rims and spokes would do more then ceramic bearings.

Ceramic bearings are beneficial in environments not requiring grease lubrication,” says Lew. But a bicycle is expected to cope with a vast range of conditions, rain and dirt, and where maintenance schedules may be less than optimal, and the last thing you want is to ride bearings without grease. It’s this requirement to cope with the conditions common to cyclists that offset the promised lower rolling resistance of a ceramic bearing, according to Paul Lew.


“The rolling resistance of a ceramic bearing compared to an ABEC 3, 5 or 7 steel ball bearing is offset by the resistance of the grease,” he says. “In order for a ceramic ball bearing to out-perform a steel ball bearing, grease is not an option. Does this mean I should run my ceramic ball bearings dry or with light oil? Yes, but you won’t like the result in an environment where the bearings can become contaminated. If you run your bearings dry they will feel gritty and rough.”
 

Alaskan

Well-Known Member
have you tried other high end hubs? I doubt most people could tell the difference. dirt and stuff in ceramic bearings is worse then in bearings with grease. I mean on a high end race bike maybe but on a e bike? you could never tell the difference in rolling resistance and they add a huge cost to the hub. the money spent on much better rims and spokes would do more then ceramic bearings.

Ceramic bearings are beneficial in environments not requiring grease lubrication,” says Lew. But a bicycle is expected to cope with a vast range of conditions, rain and dirt, and where maintenance schedules may be less than optimal, and the last thing you want is to ride bearings without grease. It’s this requirement to cope with the conditions common to cyclists that offset the promised lower rolling resistance of a ceramic bearing, according to Paul Lew.


“The rolling resistance of a ceramic bearing compared to an ABEC 3, 5 or 7 steel ball bearing is offset by the resistance of the grease,” he says. “In order for a ceramic ball bearing to out-perform a steel ball bearing, grease is not an option. Does this mean I should run my ceramic ball bearings dry or with light oil? Yes, but you won’t like the result in an environment where the bearings can become contaminated. If you run your bearings dry they will feel gritty and rough.”
Actually Onyx uses and recommends a very light viscosity, additive free grease by Kluber of Austria for packing their ceramic bearings. It takes less than two minutes to strip down the hub plus a few more minutes with a bearing pull to remove the bearings, a few more minutes to remove one dust cover, clean out the bearings and apply fresh grease. The whole process of disassembly, repacking bearings and reassembly takes perhaps a half hour.

I get that Onyx hubs are heavier and more costly than most but their rolling and other properties makes them a well worthy choice in more than just race bikes. Having ridden one, I strongly disagree with your comparison and conclusion, which appears to be more informed by personal bias and not by any direct experience with them.
 

fooferdoggie

Well-Known Member
Actually Onyx uses and recommends a very light viscosity, additive free grease by Kluber of Austria for packing their ceramic bearings. It takes less than two minutes to strip down the hub plus a few more minutes with a bearing pull to remove the bearings, a few more minutes to remove one dust cover, clean out the bearings and apply fresh grease. The whole process of disassembly, repacking bearings and reassembly takes perhaps a half hour.

I get that Onyx hubs are heavier and more costly than most but their rolling and other properties makes them a well worthy choice in more than just race bikes. Having ridden one, I strongly disagree with your comparison and conclusion, which appears to be more informed by personal bias and not by any direct experience with them.
but is it worth the extra 500 or so for the bearings? it has nothing to do with bias but practicality. The bosch systems drag is going to negate anything the expensive bearings will add. buying better rims and spokes I bet will add more to the wheels quality then going from steel to ceramic bearings. just my opinion. I think it is like high end audio cables they may or may not had an improvement but when your paying your music through a mp3 player it is a moot point. a e bike is a mp3 player of bikes in efficiency. I did the same thing I bought chris king hubs for my recumbent back when they were the best.
 
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Alaskan

Well-Known Member
but is it worth the extra 500 or so for the bearings? it has nothing to do with bias but practicality. The bosch systems drag is going to negate anything the expensive bearings will add. buying better rims and spokes I bet will add more to the wheels quality then going from steel to ceramic bearings. just my opinion.
The gen 4 Bosch systems have all but eliminated drag so the benefit of a hub with reduced drag is quite noticeable. I live at the top of a hill with a 5-7% grade. My bike with an Onxy hub left to roll down the hill without pedaling is going 38 mph at the bottom while my bike with a conventional hub is doing 34.4 This is on the same model and size tires.

You have yet to address the cost versus benefit equation on carbon versus aluminum rims. Carbon rims save on average of .6 lbs. per wheel or 1.2 pounds total. The cost of this weight saving is right around $1,000. A new Onyx hub costs around $450, $200 more than your DT Swiss. Way better to reduce carbs and loose a few pounds than spend all that money on carbon rims.

My point here is that a case can be made for either option to improve your bike's performance. You have your obvious bias and clearly I have mine.
 

fooferdoggie

Well-Known Member
my hubs would cost the same with the high end ceramic bearings. but you cant compare two different bikes that weight so much different. you have to eliminate so many variables. I Did tests on my recumbent it was one of the worlds fastest bikes a gold rush with a fairing. I tested tires and PSI and I saw a small difference on my hill I rolled down every day. but I used the same bike the same weight as possible and the same aerodynamics. wind would be a much bigger factor weight psi and such. eliminating all other factors is extremely hard. but a stiffer wheel will make more of a difference. just a difference of 20 psi gave me a few mph difference on the cost. thinner tires did better too. this was with Chris king hubs and areo deep v rims. Then you have the temperature. that will change things too and you would need the same wired biek computer too you cant reply on Bosch's system to give accurate speed.
 
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Greydog

Member
Region
USA
but is it worth the extra 500 or so for the bearings? it has nothing to do with bias but practicality. The bosch systems drag is going to negate anything the expensive bearings will add. buying better rims and spokes I bet will add more to the wheels quality then going from steel to ceramic bearings. just my opinion. I think it is like high end audio cables they may or may not had an improvement but when your paying your music through a mp3 player it is a moot point. a e bike is a mp3 player of bikes in efficiency. I did the same thing I bought chris king hubs for my recumbent back when they were the best.

Worth matters only to the buyer. I like you analogy to audio cables. It just so happens that I have a $30K 2ch sound system and cables do make a difference in sound-XLR, RCA and USB Cables. I have some $400 cables and they sound better than $100 cables for sure and it is worth it to me for the small improvement in sound. I know many people that use cables costing $2K or more. $400 is my limit and $2K cables are not worth it to me.

It is also worth it for me to lighten my Civante by 4-5 pounds and use faster tires even though it may not matter much on an Ebike. Some may not agree.
 

Deacon Blues

Well-Known Member
Before the pandemic hit I took out two Specialized Creos for test rides. One was a base aluminum model (32 pounds) and the other was a much higher end carbon model (28/29 pounds).
I rode both bikes, back-to-back, along the same route, which had a very steep, short hill. I rode the aluminum bike first, then the carbon. To my surprise I could actually notice the weight difference (3 to 4 pounds) on the really steep hill. The carbon bike was easier to ride up the hill.