Swapped my 44T chainring for a 52T

TForan

Well-Known Member
on my Juggernaut Ultra and I sure like the results. It went from a two speed to five unusable gears. I still won't use the lowest four gears but it did exactly what I wanted. Not sure on top speed but I'd say around 37. I personally don't want to ride a bike at 37 mph, so I'm guessing. New SRAM cassette, chainring and chain.

I think I'm pretty much done with personalizing this bike. It just works for me.
 

Attachments

Yeah, I was looking pretty hard at getting the Ultra FS. Running through some gear calculations it became quite clear that it needed that larger chainring.
 

TForan

Well-Known Member
Yeah, I was looking pretty hard at getting the Ultra FS. Running through some gear calculations it became quite clear that it needed that larger chainring.
I agree. It has eliminated the want for one more gear. Should have done it a long time ago.
 

Deafcat

Active Member
Have you done a top speed run ? And does the chainring size affect the speedo ?
Speed sensor is on the rear wheel, it's not affected by anything but the wheel diameter setting. Top speed verified by city radar speed check, 55 km/h on flat ground, but I can easily push it to 60 km/h.
 

FlatSix911

Member
Thinking about swapping my 38T chainring to a 44T to increase max speed from 32 to 38 at a cadence of 70.


Cadence Gear

30

40

50

60

70

80

90

Cadence Gear

38x11

14.09

18.78

23.48

28.17

32.87

37.56

42.26

38x11

38x13

11.92

15.90

19.87

23.84

27.82

31.79

35.77

38x13

38x15

10.33

13.77

17.22

20.66

24.10

27.55

30.99

38x15

38x17

9.15

12.19

15.24

18.29

21.34

24.39

27.44

38x17

38x19

8.17

10.89

13.61

16.33

19.05

21.78

24.50

38x19

38x21

7.39

9.85

12.32

14.78

17.24

19.71

22.17

38x21

38x24

6.45

8.60

10.75

12.90

15.05

17.20

19.35

38x24

38x28

5.55

7.40

9.25

11.11

12.96

14.81

16.66

38x28

38x32

4.86

6.48

8.10

9.72

11.34

12.96

14.58

38x32

38x36

4.33

5.77

7.21

8.66

10.10

11.54

12.98

38x36

44x11

16.33

21.78

27.22

32.66

38.11

43.55

48.99

44x11

44x13

13.80

18.40

23.00

27.60

32.20

36.80

41.40

44x13

44x15

11.96

15.95

19.94

23.93

27.91

31.90

35.89

44x15

44x17

10.57

14.10

17.62

21.15

24.67

28.20

31.72

44x17

44x19

9.47

12.63

15.79

18.94

22.10

25.26

28.42

44x19

44x21

8.57

11.43

14.29

17.15

20.01

22.86

25.72

44x21

44x24

7.47

9.96

12.45

14.94

17.43

19.92

22.41

44x24

44x28

6.41

8.55

10.68

12.82

14.96

17.09

19.23

44x28

44x32

5.63

7.51

9.39

11.27

13.15

15.02

16.90

44x32

44x36

4.98

6.64

8.30

9.96

11.62

13.28

14.94

44x36
 
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TForan

Well-Known Member
Speed sensor is on the rear wheel, it's not affected by anything but the wheel diameter setting. Top speed verified by city radar speed check, 55 km/h on flat ground, but I can easily push it to 60 km/h.
I know you ride long stretches but can you maintain that speed or short bursts only ?
 

dgroebl

New Member
I too have a Juggernaut Ultra and I also upgraded from a T44 to a T52, and then to a T58. I'm using my bike exclusively for commuting and I found the stock T44 chainring to be silly. With the T44 I would only ever use the highest gear. The T52 was a huge improvement as it allowed me to use a few of my other higher gears. I paid almost $100 for the SRAM T52 gear on Amazon. I then found a T58 gear on AliExpress for $30 and I figured since it was so inexpensive I'd give it a shot. After riding with the T58 for several months now I can confidently say that I think it's a much more appropriate chainring for the Juggernaut Ultra. Finally, my bike now feels like a multi-speed bike. I find that I use all of my gears now! Even with this massive T58 chainring and my 240lbs body. If I'm in the lowest gear and waiting at a red light, once that light turns green and I hit the thumb throttle the bike will wheelie off the line! So I really can't imagine why anyone would ever need a smaller sized chainring with this bike. As far as cruising and the top end goes, I have hit a max of 35.5mph for a brief moment with a slight downhill grade. Cruising is great now, I find that I can quickly get to 17+ mph, and easily cruise in the low twenties or even in the high twenties depending on how much work/assist I'd like to use. I think this really is a sweet spot and I'm quite happy with this setup.
 

dgroebl

New Member
Also, here is a great bike gear calculator that will let you compare two setups.

http://ritzelrechner.de/?GR=DERS&KB=44&RZ=11,13,15,17,19,21,24,28,32,37,42&UF=2312&TF=75&SL=3.5&UN=MPH&DV=ratio&GR2=DERS&KB2=55&RZ2=11,13,15,17,19,21,24,28,32,37,42&UF2=2312

Also, here are the calculations for my T58 set up vs. the stock T44. It shows that with a cadence of 75 I should be able to cruise at 34mph which is not quite right, but it certainly shows that this is a huge improvement over the stock T44

Photo Link
 

Deafcat

Active Member
I know you ride long stretches but can you maintain that speed or short bursts only ?
Maintain it for as long as I like, assuming the lights stay green, nobody cuts me off, no pedestrians crossing, and so forth. But generally I keep the speed around 40-45 km/h on the street, more efficient.
 

TForan

Well-Known Member
I too have a Juggernaut Ultra and I also upgraded from a T44 to a T52, and then to a T58. I'm using my bike exclusively for commuting and I found the stock T44 chainring to be silly. With the T44 I would only ever use the highest gear. The T52 was a huge improvement as it allowed me to use a few of my other higher gears. I paid almost $100 for the SRAM T52 gear on Amazon. I then found a T58 gear on AliExpress for $30 and I figured since it was so inexpensive I'd give it a shot. After riding with the T58 for several months now I can confidently say that I think it's a much more appropriate chainring for the Juggernaut Ultra. Finally, my bike now feels like a multi-speed bike. I find that I use all of my gears now! Even with this massive T58 chainring and my 240lbs body. If I'm in the lowest gear and waiting at a red light, once that light turns green and I hit the thumb throttle the bike will wheelie off the line! So I really can't imagine why anyone would ever need a smaller sized chainring with this bike. As far as cruising and the top end goes, I have hit a max of 35.5mph for a brief moment with a slight downhill grade. Cruising is great now, I find that I can quickly get to 17+ mph, and easily cruise in the low twenties or even in the high twenties depending on how much work/assist I'd like to use. I think this really is a sweet spot and I'm quite happy with this setup.
I was unaware of a 58T. Do you think it's more wear on the gears ? Do you have the nylon or steel gears ?
 

Deafcat

Active Member
IMO, 58T is really pushing it for momentary torque loads. I'm sure his motor has steel gears, but that's not where the risk is... It's the output clutch that will be destroyed by overloading it (different from the pedal freewheel in the motor). Be careful with that throttle from a complete stop...
 

AZOldTech

Active Member
Before you go changing chainrings and/or cassettes, I suggest you use this extremely user friendly web page and enter your specifics (cogs/chainrings/tire size) to see the speed you could get at a comfortable cadence RPM.
 
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TForan

Well-Known Member
IMO, 58T is really pushing it for momentary torque loads. I'm sure his motor has steel gears, but that's not where the risk is... It's the output clutch that will be destroyed by overloading it (different from the pedal freewheel in the motor). Be careful with that throttle from a complete stop...
I have a feeling that part might be hard to locate. 52T is fine with me. In fact, I'm done spending money on this bike. At least for this month.;)
 

Deafcat

Active Member
I have a feeling that part might be hard to locate. 52T is fine with me. In fact, I'm done spending money on this bike. At least for this month.;)
Actually it's not a difficult part to get these days, Biktrix stocks em as do a few others.
 

TForan

Well-Known Member
Actually it's not a difficult part to get these days, Biktrix stocks em as do a few others.
That's good to hear. Now, I remember I have one in the garage , when Roshan sent me the metal gear set. Just never have installed them because the nylon ones haven't failed .
 

dgroebl

New Member
Yeah, I've been concerned about overloading the motor with the larger chainring. I think though the low gears still have an extremely low ratio. My sense is that the danger is when I have to come to an emergency stop and have forgotten to change down. Then as I start to pedal the bike is super hard to move and if I've forgotten to turn down the assist my motor is pushing super hard.

I'm interested in these metal gears you speak of. You say that Biktrix has them in stock? And whats this Output clutch? Do they stock those as well? Does anyone have a picture of one of these?
 

TForan

Well-Known Member
Yeah, I've been concerned about overloading the motor with the larger chainring. I think though the low gears still have an extremely low ratio. My sense is that the danger is when I have to come to an emergency stop and have forgotten to change down. Then as I start to pedal the bike is super hard to move and if I've forgotten to turn down the assist my motor is pushing super hard.

I'm interested in these metal gears you speak of. You say that Biktrix has them in stock? And whats this Output clutch? Do they stock those as well? Does anyone have a picture of one of these?
Have you seen this ? How old is your bike ? You probably have the metal gears. Mine is a real early one.