Ultra Chainring Swap?

AHicks

Well-Known Member
Region
USA
City
Snow Bird - Summer S.E. Michigan, Winter Gulf Coast North Central Fl.
Hi Everyone.

I find myself using the small cluster gears too often (6th through 9th, which is an 11 tooth) even while cruising at just moderate speeds in the low teens. Would much rather use the cluster gears with more teeth to handle/spread out the Ultra loads better. Have little need for the power/climbing ability offered by 1st through 4th gears now. This in mind, I would like to swap my OEM 44t chainring for a 48t. I see all sorts of available gears for the BBSxx series motors, but nothing specific to the Ultra. Is that because they use the generic 130mm 5 bolt gears, or are the Ultra gears just a PIA to find? Are the chain gears different for mountain bike set ups vs. fatty?

For those that have swapped already, where did you get the new gear?

Any help/guidance appreciated. -Al
 
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I notice that is focused on replacing the spyder the chainring bolts to but I think in the following 5 pages of that thread some listed where they bought new chainrings. If not I can look up my recent reading and find other info in the WW threads.
 
Thanks Merle. Clearly clueless at this point, looks like I'll need to check into this further. In my case, the bike WAS a fattie, now converted to 27.5". Because I used the original 170mm hub over again (now laced to a 27.5" rim), I doubt the chain line has changed, but with the tire clearance I have at this point (LOTS!), I may want to check my options.

Assuming the current spider has something close to workable offset, can it be reused, replacing the chainring only to get to my 48t objective?
 
I'm not at all sure but it sounds like chainrings are standard. Ones I saw pictured were just nice in this way or that as in - custom.

Edit: The spyder on the other hand, which it does seem you won't need, was specific to the Ultra.
 
I started that WW thread that Merle linked to.
My WW bike has the standard Bafang 42t chain ring and like you I want to be able to cruise in a larger cog. Presently, even with the Fat spider on my bike, I still get some chain skip in the 11t cog (smallest).
I plan on purchasing a larger chain ring (48t) in the near future.
The larger chain rings can be found on Amazon, ebay, and Alibaba.

Here's an example from Amazon.com: https://www.amazon.com/DECKAS-104BC...r+9/10/11-Speed+(Round)&qid=1638033194&sr=8-1

Make sure it's a BCD104 compatible ring for the Ultra motor.
 
I started that WW thread that Merle linked to.
My WW bike has the standard Bafang 42t chain ring and like you I want to be able to cruise in a larger cog. Presently, even with the Fat spider on my bike, I still get some chain skip in the 11t cog (smallest).
I plan on purchasing a larger chain ring (48t) in the near future.
The larger chain rings can be found on Amazon, ebay, and Alibaba.

Here's an example from Amazon.com: https://www.amazon.com/DECKAS-104BCD-Narrow-Chainring-11-Speed/dp/B082KGR9S9/ref=sr_1_1?keywords=104BCD+40T+42T+44T+46T+48T+50T+52T+Narrow+Wide+Chainring+Single+Chainring+for+9/10/11-Speed+(Round)&qid=1638033194&sr=8-1

Make sure it's a BCD104 compatible ring for the Ultra motor.

Perfect! Exactly the info I was after. Thanks so much! -Al
 
Pretty sure the Ultra comes standard with the 130BCD ( Bolt Circle Diameter ) set-up. Limets on larger and smaller size chainrings depending on chainstay clearance dims.
If going smaller than about 38t or 39t you gotta make the BCD smaller and drop down in size and probably have to go with a 4 bolt pattern instead of the 5 bolt.
Personally I have had good luck with Wolftooth brand, Alum material but seems to last well. You also want a narrow/wide tooth pattern on whatever chainring you go with.
Fitting a smaller size might also require spacing in or out to keep the chainline centered on your cassette to facilitate shifting from one end to the other.
 
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Yup, knew I was looking for a 5 bolt. I will verify/confirm the bolt distance prior to ordering.

Biggest piece I was after is regarding the fact I can use the generic chainrings.

I'll post a link to the 48t I end up after I confirm it works as planned for those following later on.

Thanks!
 
I put a Blackspire 49T (Made in Canada nearby - so my local preference) on mine last spring, and I've been very happy with it. 49 seems like the right spot for me, and I live in 6/7 most of the time now, but actually use the entire range reasonably consistently. Probably still don't use 1 much, but it's still good to have it for the occasional loaded uphill start.


img_0062-jpg.85084
 
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I put a Blackspire 49T (Made in Canada nearby - so my local preference) on mine last spring, and I've been very happy with it. 49 seems like the right spot for me, and I live in 6/7 most of the time now, but actually use the entire range reasonably consistently. Probably still don't use 1 much, but it's still good to have it for the occasional loaded uphill start.


img_0062-jpg.85084
Great. Can you tell me a bit about the chain? How many links did you go with? Can’t see it on the pkg.
 
Great. Can you tell me a bit about the chain? How many links did you go with? Can’t see it on the pkg.
I'm not sure the actual link count, but that chain was at least 4-6 links longer than necessary, so I pulled a bunch out and added a master link for ease of maintenance. Wear of the entire package has been much better than the stock combo, and I think I'll comfortably see 1,500kms or more before I even begin to approach .5 wear. I'm getting close to that, and the cheap gauge still suggests it's somewhere between .7 & .5. Considering I'm a big guy that rides hard and fast with only basic maintenance, I'm completely happy with that interval for the Ultra. Of course my other 750w hub drive has 1,500kms with almost no measurable wear at all, but the Ultra is a bit of drivetrain grinder when used to its performance potential...
 
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Like the idea your new gear is made from 7075. Also good to hear your happy with a 49 as I'm sure I'm not cruising as fast as you do. Riding for pleasure, not to really get anywhere. I'm generally just putting along at 10-14 mph depending on surface and terrain. 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
 
Like the idea your new gear is made from 7075. Also good to hear your happy with a 49 as I'm sure I'm not cruising as fast as you do. Riding for pleasure, not to really get anywhere. I'm generally just putting along at 10-14 mph depending on surface and terrain. 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
Right!?

That seriously needs to become one of the stock tunes - on the cruisers anyway.

And I haven't even begun to wear the paint off the chainring at 1,400kms. Very good quality, BUT it is an expensive chainring.
 
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