Ultra Chainring Swap?

[theemartymac]

Have now had a chance to spend some quality time with the Frey "smooth" tune. I'm always paying attention to what it's doing, but try as I might, I have no desire to change anything about it. A tinkerer at heart, I find that a pleasant surprise. -Al

I'd have to say, that for my use the Frey Tune makes a really good sport mode, and I don't really want/need any more power. I would like a similar smooth profile with a true Eco tune though, as the Ultra is a battery hog.

 

[Deacon Blues]

I wish I'd know about this Canadian source before I ordered my wolf Tooth chain ring. Your source is much cheaper.

You said your tooth count is 49. I don't see a 49 listed.

 

[AHicks]

I'd have to say, that for my use the Frey Tune makes a really good sport mode, and I don't really want/need any more power. I would like a similar smooth profile with a true Eco tune though, as the Ultra is a battery hog.

I'm still on my first charge since returning for the winter season where this bike is used, bet REALLY liking what I'm seeing from a battery mileage stand point. Issue is I'm not real sure it's the Smooth tune, or the change to the 27.5x2.8 Schwalbe Super Moto-X tires. My point is, I think there's a good chance your tires are what's costing you the "battery hog" mileage. More later as I get a few more charges to base that opinion on (currently 34 miles at 48.5 volts, I charge at 46, so we may pull 40 miles on this charge). -Al

 

[theemartymac]

I wish I'd know about this Canadian source before I ordered my wolf Tooth chain ring. Your source is much cheaper.

You said your tooth count is 49. I don't see a 49 listed.

It's an older model that may be out of production now I think, but they distribute relatively widely so one may be available through one of their online retailers.

If not, a 52 series would not be a bad option for an Ultra either as long as you aren't looking for a really low 'granny' gear option for off-road. The motor certainly doesn't need it as the power is great down low. I found the 46-49 move was about a 1.5 gear shift in my case, and I still have plenty of range on the low end, so moving another 1.5 (with a 52) would still probably work just fine, and give you a top speed around 36 or 37 mph with a reasonable cadence.

 

[theemartymac]

I'm still on my first charge since returning for the winter season where this bike is used, bet REALLY liking what I'm seeing from a battery mileage stand point. Issue is I'm not real sure it's the Smooth tune, or the change to the 27.5x2.8 Schwalbe Super Moto-X tires. My point is, I think there's a good chance your tires are what's costing you the "battery hog" mileage. More later as I get a few more charges to base that opinion on (currently 34 miles at 48.5 volts, I charge at 46, so we may pull 40 miles on this charge). -Al

The smooth tune seemed to give me another 10-15% range, but since I ride fast on my commutes (avg speeds of 35-40kph), I get maybe 30-40kms to a battery on a bad day, or 50 on a good one. I can certainly pull 60-70 in eco at a cruising pace, but I can do twice that on the hub bike if I don't need the Ultra power. I think for me, the new model with the 30AH dual battery option would be perfect for range, but I won't touch the CANBUS model until someone fully cracks it and gets a good tune developed - similar to the Frey.

And I still love my fat tires. Like Love-love! ;-)

 

[AHicks]

OK, no badgering on the fat tires.

 

[AHicks]

To update my chain ring change- thought I would post for anyone following considering making a change.
I went with a 48t BCD130 5 bolt "sharktooth" chain ring (from the OEM 44t). Probably not the best available, but it should last me quite a while. I've ridden it a bit now, and it resulted in dropping about 1 gear. In other words, where I was cruising in 6th, I'm now using 5th. Where I was using 5th, I'm now using 4th. While this move was in the right direction, I was hoping to drop 2 gears, so not quite what I was thinking/hoping for. If this gear ever wears out to the point it must be replaced I will likely replace it with a 52t. Until then it's probably close enough. Noteworthy maybe, I do catch myself cruising at a bit higher speeds than I used to run (20+mph), but generally that's a downhill scenario.

This is for street use in a hilly area running 27.5x2.8" tires.

Amazon.com

 

[Deacon Blues]

I also swapped my 42t to a 48t front ring on my Watt Wagons UC Pro, with the Ultra motor.
The swap did allow me to cruise at a higher speed while maintaining a 75-80 cadence, but the chain now skips in the 11t and 13t cog. With the 42t front ring the chain only skipped in the 11t cog.

 

[rtp]

I also swapped my 42t to a 48t front ring on my Watt Wagons UC Pro, with the Ultra motor.
The swap did allow me to cruise at a higher speed while maintaining a 75-80 cadence, but the chain now skips in the 11t and 13t cog. With the 42t front ring the chain only skipped in the 11t cog.

Did you lengthen your chain on the swap?
# of gears and where does the current chainring 'center' on in the rear?
Is the replacement chainring a narrow-wide?

 

[AHicks]

I also swapped my 42t to a 48t front ring on my Watt Wagons UC Pro, with the Ultra motor.
The swap did allow me to cruise at a higher speed while maintaining a 75-80 cadence, but the chain now skips in the 11t and 13t cog. With the 42t front ring the chain only skipped in the 11t cog.

My thought on the skipping would be that if alignment and chain tension is set correctly, and the gears aren't worn too bad, you might want to go with an even bigger front ring. Thought being that there's not much of the chain really engaging an 11 tooth sprocket. That's placing a LOT of stress on the chain and the sprocket, so if you apply a lot of power, it's way more likely to slip than a sprocket with more teeth. A cartridge with a bigger small gear (13t-14t?) would do the same thing (reduce the stresses vs. those of an 11t).

 

[Deacon Blues]

Did you lengthen your chain on the swap?
# of gears and where does the current chainring 'center' on in the rear?
Is the replacement chainring a narrow-wide?

1. I didn't length the chain. I figured since I swapped my rear 11-50 cassette for a 11-42 I might be able to get away with not lengthening the chain.
2. I haven't checked to see what cog the chain is on when the chain is straight.
3. The replacement chainring is a Wolf Tooth Components CX, which I don't think is a narrow-wide.

 

[PedalUma]

Hi,
Excuse me for arriving late to the party and just jumping in. I have found that the narrow/wide chainrings have a lot more bite. If you pull in the B-screw the chain will have greater contact with more cog teeth. The higher end of the cassette has far fewer teeth per revolution so it will ware out much faster. If it is skipping they are most likely worn. Putting on a new chain will make it worse.

 

[JRA]

I find myself on the other side of this discussion as I do alot of off road climbing at low/medium assist levels where I find myself using the lower range cogs of my 11/50 cassette. There has been some discussion on the boards about chain rubbing on upper chain stays on some bikes similar to mine when in the 50t which isn't a problem for me but last ride I did hear an intermittent consistent slight rub noise and upon inspection I found it was because the rear wheel had gone slightly out of true in one spot and the chain was rubbing on the tire. Easy enough to fix but I hadn't realized just how close it was.

So as I am happy enough with the speed I am able to climb in mode 2/3, of 5, and don't want to up the watts to get out of the larger cogs I decided I want to go to a smaller chainring and aiming for a 34t narrow/wide 104bcd that I have. However it will take one of the Christini adapters to do so and I chose to go with the more standard offset one rather than the fat specific one. This should get me down a few cogs for the most part and really put some low gears on tap for taking it easy on the thighs/quads on long ride climbs and especially on switchbacks where the ability to spin a low gear is key for me to get around them.

I am not concerned about losing speed on flat sections as I think I will still be able to spin out at least 24mph which is fine as I ride with guys that either have no assist or that cut out at 20 anyway. Downhill speeds are not a problem with a 200lb rider on a 60+lb. bike when gravity has its way. I have never experienced any skipping in the 11t and hopefully won't but I will be taking out at least a few links to keep my derailleur attitude the same as it is now.

Edit: Adding elevation profile of typicalish ride.

And yes that min ele is correct as I went over the Cape and down to the beach on a trail. The rest was some road and mostly gated logging road. Saw about 40 elk @33.20. They were laying down in two groups on the logging road staying out of the wind that is going on here today.

 

[rtp]

1. I didn't length the chain. I figured since I swapped my rear 11-50 cassette for a 11-42 I might be able to get away with not lengthening the chain.
2. I haven't checked to see what cog the chain is on when the chain is straight.
3. The replacement chainring is a Wolf Tooth Components CX, which I don't think is a narrow-wide.

It might be worth checking your chainline and seeing if it's mor inboard (towards the larger sprockets) and using spacers if/as need be, or possibly moving the chainrigh to the outside of the spider if possible. A pic is worth 1000 words here, as the frame and wheel will have an impact on this along with the spider etc. I'd definitely adjust the derailleur as @PedalUma mentions as there's already not a lot of engagement on the smaller gears and don't want to make it worse.

How many miles on your bike now?

 

[PedalUma]

off road climbing at low/medium assist levels where I find myself using the lower range cogs of my 11/50 cassette.

So as I am happy enough with the speed I am able to climb in mode 2/3, of 5, and don't want to up the watts to get out of the larger cogs

I am not concerned about losing speed on flat sections as I think I will still be able to spin out at least

This one bike has a 42 which is good for just about everything for me. You are right about the switchbacks on climbs. This muddy hill is steeper than it looks. Zoom in on the final photo, it is a mucky climb.

 

[Slick50]

I just got a Rize RX (non fatbike) and feel like I'm running out of gears with the stock 44 tooth chainring at higher speeds. I like the stock version because it has a ring to keep the chain from falling off the outside. I have searched for something in 50 or 52 tooth narrow wide. I had success stopping chain drop with a narrow-wide on the BBS02 (the chain was dropping on the inside) so I would like to prevent this (premptive) for the M620. I understand it is 130BCD, 5 bolt pattern. Has anyone found something strong enough for this application? I am hoping to drop one to two gears with the swap for slower cadence at higher speed, say 20+ mph (off road of course ) and to stay away from smallest cogs in the rear. I also understand that gear choice and torque with the larger ring is important for drive train preservation. I saw a few chainrings on Amazon but they were not narrow-wide and of unknown quality. Any suggestions?

 

[PedalUma]

It is shaped like a pie pan, so it brings in the chain line. It is also narrow wide.

Premium CNC Bling Ring – Bafang Chainring BBSHD – 52T - Lekkie

The Lekkie Bling Ring - Bafang Chainring for the Bafang mid drive motors are being celebrated as the #1 performance upgrade for the BBSHD system. The original, and still the best. Bling Ring HD is designed specifically for the Bafang BBSHD motors. Is this compatible with your motor? Download the...

lekkie.tech

the chain was dropping on the inside

 

[theemartymac]

It is shaped like a pie pan, so it brings in the chain line. It is also narrow wide.

Premium CNC Bling Ring – Bafang Chainring BBSHD – 52T - Lekkie

The Lekkie Bling Ring - Bafang Chainring for the Bafang mid drive motors are being celebrated as the #1 performance upgrade for the BBSHD system. The original, and still the best. Bling Ring HD is designed specifically for the Bafang BBSHD motors. Is this compatible with your motor? Download the...

lekkie.tech

Last time this came around, you couldn't get a bling ring for the Rize 130bcd?

 

[Slick50]

Does that fit the Ultra? I don't see the 130bcd in the description for the BBSHD there. Am I overlooking that information or is it assumed for the BBSHD? I am not familiar enough to know what fits various motors. They are out of stock right now. If someone has experience with another chainring for the Ultra that prevents the chain from dropping, please advise. I haven't seen anything with a guard of any sort in a 50 or 52. I also am not sure if 50 or 52 will result in the 1-2 gear difference I am seeking so I can stay away from small cogs. Any help appreciated.

 

[theemartymac]

Does that fit the Ultra? I don't see the 130bcd in the description for the BBSHD there. Am I overlooking that information or is it assumed for the BBSHD? I am not familiar enough to know what fits various motors. They are out of stock right now. If someone has experience with another chainring for the Ultra that prevents the chain from dropping, please advise. I haven't seen anything with a guard of any sort in a 50 or 52. I also am not sure if 50 or 52 will result in the 1-2 gear difference I am seeking so I can stay away from small cogs. Any help appreciated.

49T got me ~1.5 gears from 46T stock. Stands to reason 52 would be ~3 gears. Certainly a safe bet for at least 2...

And the Bling ring was originally designed specifically for the BBSHD, and there were some posts a couple of years back on various forums by folks who have sourced adapters for other spiders, but when I looked, I couldn't find any. Custom machining one would be $$$ unless you have a buddy with a C&C machine. I went with a Blackspire 49T (posted on page 1 of this thread), and have had no chain drops on the new drivetrain - but I only lightly trail ride, so not exactly bashing it. Last Gen Rize Ultras were 130BCD with no offset, but probably worth validating the 2022 are the same. On my 2020, I could mount to the outside of the spider if I swapped with the chainring guard, and that has provided ideal alignment for 6/7, which is where I spent 80% of my time when commuting and cruising. I'd stay on the inside if you are looking to stay on the larger cogs most of the time and want alignment for 4/5.