Just got the ultra eagle - getting used to the midrive?

Appreciate all the detailed info. Can you confirm if a 50t wolftooth chainring will fit on this bike and do I need to change the cassette too? I would like to see the difference with the bigger chainring.

This is the chainring I would like to get:

I confirmed with the company it will work so I ordered it. I wonder since I'm so used to a 52t chainring on my rear hub if this is a reason for everything feeling different for me. Will this help me maintain the higher speeds? Because I keep complaining that my speed drops too low when I'm tired with comfortable pedaling unlike my rear hub which feels like I'm putting in less effort for higher speeds. I decided to go with 50t on the mid drive because it's a more powerful motor. Anyway I'm going to try it and if I don't like it I can switch back. I have to take it into the shop anyway to find out why my chain is dropping when I try to shift to the highest gear so at the same time I'll have them upgrade the chainring.
 
I confirmed with the company it will work so I ordered it. I wonder since I'm so used to a 52t chainring on my rear hub if this is a reason for everything feeling different for me. Will this help me maintain the higher speeds? Because I keep complaining that my speed drops too low when I'm tired with comfortable pedaling unlike my rear hub which feels like I'm putting in less effort for higher speeds. I decided to go with 50t on the mid drive because it's a more powerful motor. Anyway I'm going to try it and if I don't like it I can switch back. I have to take it into the shop anyway to find out why my chain is dropping when I try to shift to the highest gear so at the same time I'll have them upgrade the chainring.
Make sure you get a 5 bolt 130BCD. Not 110.
 
I confirmed with the company it will work so I ordered it. I wonder since I'm so used to a 52t chainring on my rear hub if this is a reason for everything feeling different for me. Will this help me maintain the higher speeds? Because I keep complaining that my speed drops too low when I'm tired with comfortable pedaling unlike my rear hub which feels like I'm putting in less effort for higher speeds. I decided to go with 50t on the mid drive because it's a more powerful motor. Anyway I'm going to try it and if I don't like it I can switch back. I have to take it into the shop anyway to find out why my chain is dropping when I try to shift to the highest gear so at the same time I'll have them upgrade the chainring.
That's easy fix if it's dropping there is 2 bolts on the derailleur one is for the high cog and one for low cog I had you just need to tighten if yours is the 11 speed then the one on the right i had to put mine almost all the way in before it stopped it's pretty easy to do this bike was my first time messing with it that part only took 2 mins but I also have a stand for it
 
That's easy fix if it's dropping there is 2 bolts on the derailleur one is for the high cog and one for low cog I had you just need to tighten if yours is the 11 speed then the one on the right i had to put mine almost all the way in before it stopped it's pretty easy to do this bike was my first time messing with it that part only took 2 mins but I also have a stand for it

I have a stand I'll try that - appreciate it!! I can't tell which one to tighten though I have the 12 speed
 

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That's easy fix if it's dropping there is 2 bolts on the derailleur one is for the high cog and one for low cog I had you just need to tighten if yours is the 11 speed then the one on the right i had to put mine almost all the way in before it stopped it's pretty easy to do this bike was my first time messing with it that part only took 2 mins but I also have a stand for it

Was it this one? It was out pretty far and I tightened it as I was tightening it looked the like the derailer was moving closer inwards and chain possibly getting tighter around the cassette? Going to test drive now.
 

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That's the B-screw. Your High and Low limit screws are the two small screws right next to each other to the right in your picture. H limit is on the left, L limit is on the right. I highly suggest watching the Park Tool Rear Derailleur Adjustment video on You tube.
 
That's the B-screw. Your High and Low limit screws are the two small screws right next to each other to the right in your picture. H limit is on the left, L limit is on the right. I highly suggest watching the Park Tool Rear Derailleur Adjustment video on You tube.

crap I went out after adjusting the b screw and now my chain/gear is clicking and slipping. I am going to head back home and bring the screw back out.

Edit: found the right screws so I need to tighten but mine aren't labeled so I'm going to take a guess
 
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That's the B-screw. Your High and Low limit screws are the two small screws right next to each other to the right in your picture. H limit is on the left, L limit is on the right. I highly suggest watching the Park Tool Rear Derailleur Adjustment video on You tube.
 
Looks like I got it now working on my stand but going to take it out now. One thing is that I cant shift into my two lowest gears (biggest cogs) but I don't need to go that low so Im not concerned with it and since I don't really know what I'm doing lol I'll just leave that as it is when I take it to the shop to upgrade the chainring they can check it out.

Appreciate the help I don't know what I'd do without this place haha! I thought I had already damaged the drivetrain!
 
Actually NEVERMIND not fixed!! Even worst!! When I start pedaling my entire power shuts off!!! I don't know what to do I guess I will just randomly start turning the screws. What the hell did I do????
 
I brought it back and just started making random adjustments and looks like it's working again. I went out for about 5 miles and no power shut off and chain didn't drop. Changing these settings could it effect power?? Why do I keep on having issues with the power totally shutting off? Normally I can boot back up while I'm still on the bike but this time as soon as I would go to pedal it would shut off so I walked it back. I wasn't even going fast or hard where you could say maybe a voltage spike. I was just in the parking lot about ready to hit the road. I was behind cars I was slow.

I must be getting used to it more because on this ride I wasn't even thinking of my rear hub and for the most part I was in level 1 and didn't even realize it then I boosted to 5 just to see the difference. It's really plenty fast in level 1 can't wait for the 50t to get here though and really wake this puppy up! But I'm not going to mess with anymore of those settings I think I still can't shift to the two lowest but I don't care at least it it didn't slip from the highest gear like it was doing before. When I take it to the shop for the chainring I'll have them take a look as well.
 
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I brought it back and just started making random adjustments and looks like it's working again. I went out for about 5 miles and no power shut off and chain didn't drop. Changing these settings could it effect power?? Why do I keep on having issues with the power totally shutting off? Normally I can boot back up while I'm still on the bike but this time as soon as I would go to pedal it would shut off so I walked it back. I wasn't even going fast or hard where you could say maybe a voltage spike. I was just in the parking lot about ready to hit the road. I was behind cars I was slow.

I must be getting used to it more because on this ride I wasn't even thinking of my rear hub and for the most part I was in level 1 and didn't even realize it then I boosted to 5 just to see the difference. It's really plenty fast in level 1 can't wait for the 50t to get here though and really wake this puppy up! But I'm not going to mess with anymore of those settings I think I still can't shift to the two lowest but I don't care at least it it didn't slip from the highest gear like it was doing before. When I take it to the shop for the chainring I'll have them take a look as well.
Yeah not gonna lie I spent 3-4 hours the one day with my bike on the stand just making adjustments and testing what it did

if you messed with the b limit screw it can throw off all your shifting as the chain will be either too tight or too slack this was my problem in the 3-4 hour learning session

First you need to get your low cogs back the the H and L screws you want to be in your highest gear when adjusting the H and lowest gear when adjusting the L you lost the last 2 cogs as your L screw is too tight now back it off a bit and you will get your last 2 back just make sure when you are in your last cog that your shifter is tight and won't allow the chain to move up again no more clicks when you press it

And repeat again with the H screw that one will adjust shifter left and right when you have it in the highest gear try to get it dead center with you small cog

After that switch back up to your highest gear and then adjust the B limit screw you want it so it's close to the cog but not so close that the gears touch or it puts too much tension on the chain about 1cm you will see the teeth on you cogs line up with the next link coming and line it up to grab the link after that it will be smooth as butter

I am now a pro at it lol and only had to adjust it 2 times now the second took me like 5 mins if you got a stand take advantage of it you lbs will probably charge you 80$ to adjust it for you that's why I bought a stand my lbs is like drop your bike off and we should be able to do it in the next 3 weeks we will call you when it's ready that was for 2 broken spokes on my last bike bought me a park tool stand online and bought a torque wrench and some tools and I can now fix most my problems and if I can't figure it out my friend google will always help me
 
On the battery level topic: I honestly recommend just using Battery Voltage instead of Percent. It's a more honest reading, will take you a bit to get used to it, but it's a proper look at charge level. You can swap between either option right inside the display settings, typically.


As for the assist difference between mid-drive and hub motor: Biggest difference is that a hub motor has to output power over the full range of rear-wheel RPM, 1:1 relationship, and this is why hub motors are only really efficient when their winding, RPM/V, wheel/tire size and average riding speed are all in their respective sweetspot in relation to each other. Peak speed is quite easy to calculate, and at what loss of efficiency, the same applies to low speed inefficiency with hubs. Geared hubs introduce a fixed reduction ratio, but otherwise mostly follow the same rules.

With mid-drives, you can alter the equation through chainring and cassette sprocket selection, and with the Bafang Ultra, it's a very easy equation to figure out, since the Ultra is designed for it's peak efficiency output at normal rider cadence. This corresponds to about 60 RPM (1 revolution per second) at the bottom bracket. At this output speed, or anything up to 100+ rpm, the Ultra motor is very happy and efficient, and so is the rider... It was designed to be this way, and it tells you a lot about the great engineering team that conceived this motor.

Thus, to get your preferred riding speeds, you need only pick the right chainring and cassette range to get what you want out of the bike. If you're a street demon who likes to match speed with city traffic, a big chainring and tall cassette are nice... For most riding, a middle/upper sized chainring with the stock cassette range does great. For more trail/climb oriented riding, a medium/smaller chainring works wonders. It's worth noting for any calculation, you will never have smaller than an 11 tooth "high" sprocket, this is the smallest possible cassette sprocket on a Hyperglide (HG) Hub Spline, the stock format (and best format for ebikes).

You sir, are a wealth of good information and also, one of the reasons I bought a Juggernaut three years ago. 👍
 
Yeah not gonna lie I spent 3-4 hours the one day with my bike on the stand just making adjustments and testing what it did

if you messed with the b limit screw it can throw off all your shifting as the chain will be either too tight or too slack this was my problem in the 3-4 hour learning session

First you need to get your low cogs back the the H and L screws you want to be in your highest gear when adjusting the H and lowest gear when adjusting the L you lost the last 2 cogs as your L screw is too tight now back it off a bit and you will get your last 2 back just make sure when you are in your last cog that your shifter is tight and won't allow the chain to move up again no more clicks when you press it

And repeat again with the H screw that one will adjust shifter left and right when you have it in the highest gear try to get it dead center with you small cog

After that switch back up to your highest gear and then adjust the B limit screw you want it so it's close to the cog but not so close that the gears touch or it puts too much tension on the chain about 1cm you will see the teeth on you cogs line up with the next link coming and line it up to grab the link after that it will be smooth as butter

I am now a pro at it lol and only had to adjust it 2 times now the second took me like 5 mins if you got a stand take advantage of it you lbs will probably charge you 80$ to adjust it for you that's why I bought a stand my lbs is like drop your bike off and we should be able to do it in the next 3 weeks we will call you when it's ready that was for 2 broken spokes on my last bike bought me a park tool stand online and bought a torque wrench and some tools and I can now fix most my problems and if I can't figure it out my friend google will always help me

Appreciate all the info. I think I am going to leave it as it is lol I didn't realize it was going to get that complicated I am barely handy with shoelaces let's just put it that way lol I have to take it to the shop anyway since I ordered a 50t chainring. But maybe that's where I screwed up I was just adjusting the screws with the chain anywhere not in the right position ex: adjusting H in the highest gear and L in the lowest. I should also look up the derailer and see which one is H and which is L as they aren't labeled. I might mess with it again when I have time I thought it was just a quick turn of the screw on the way out. Then when my power was shutting off and I brought it back no matter where I was adjusting the screws chain wouldn't go all the way to highest or lowest cog and just slipping in the middle. I just messed with it until I could go in highest gear again and it didn't slip when I took it out. So I'll just leave it as is for now.
 
Took it out again and so far so good. Im liking it!! On this last ride I had the same feeling I do on my rear hub where I don't want to come back and just keep riding!
 
Oh and the shocks are freaking awesome! Now that I have experienced proper shocks I can tell I'm not going to like my rear hub for much longer. I love going over bumpy terrain now it just rolls over so smooth and the dropper seat provides extra cushion it's so fun going over bumps which there is a lot of here in Colorado. I just came back from a trail that I haven't gone on forever since it was too bumpy for my fat tire rear hub and it was really awesome.
 
Just got my bike back with the 50t chainring and this was definitely a missing piece that had me comparing it to my rear hub with the 52t. I don't feel like I'm "spinning my wheels" anymore. I used to feel crazy spinning the pedals so fast in the highest gear but lacking that same feel as the bigger chainring. Unless it's in my head I feel like I'm going farther and getting less tired (less pedal rotations?) compared to the smaller chainring. Just like how it is on my rear hub.

Anyway I'm happy with it now and keeping it. Not going to sell it. Infact I may even sell the rear hub and go with the Biktrix juggernaut fat tire next. I am starting to feel my juiced fat tire to feel "clunky" I'm feeling all the bumps in the road now, the riding style with high end components on the ultra compared to the low end components on my juiced bike is becoming real clear. I think it would have been stupid of me to get rid of the ultra eagle and keep the juiced bike. I'm really liking the torque as well on the ultra, which isn't there with the rear hub.

I have one question and this isn't related to the Biktrix in particular but in general. When I'm going really fast 30+ I feel something weird coming from the rear I dont know how to describe it, kind of want to say feels like some kind of "rubbing" but I have experienced this on my fat tire bike as well. Only happens when I'm going fast and I feel it from the rear not sure if it's just in my head or what that feeling is. Does anybody know what I'm talking about?
 
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Just got my bike back with the 50t chainring and this was definitely a missing piece that had me comparing it to my rear hub with the 52t. I don't feel like I'm "spinning my wheels" anymore. I used to feel crazy spinning the pedals so fast but lacking that same feel as the bigger chainring. Unless it's in my head I feel like I'm going farther and getting less tired (less pedal rotations?) compared to the smaller chainring. Just like how it is on my rear hub.

Anyway I'm happy with it now and keeping it. Not going to sell it. Infact I may even sell the rear hub and go with the Biktrix juggernaut fat tire next. I am starting to feel my juiced fat tire to feel "clunky" I'm feeling all the bumps in the road now, the riding style with high end components on the ultra compared to the low end components on my juiced bike is becoming real clear. I think it would have been stupid of me to get rid of the ultra eagle and keep the juiced bike. I'm really liking the torque as well on the ultra, which isn't there with the rear hub.

I have one question and this isn't related to the Biktrix in particular but in general. When I'm going really fast 30+ I feel something weird coming from the rear I dont know how to describe it, kind of want to say feels like some kind of "rubbing" but I have experienced this on my fat tire bike as well. Only happens when I'm going fast and I feel it from the rear not sure if it's just in my head or what that feeling is. Does anybody know what I'm talking about?
Knobby tires?
 
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