Ultra Chainring Swap?

Thanks theemartymac, good stuff. This is exactly what I needed to make a decision about which chainring size and where to mount it for desired alignment and cruising gears. I don't see myself using the larger cogs often since most rides here are fairly flat. I will start with the outside mount and see how that works. I found a Wolf Tooth, 52t, 130BCD, no offset on Amazon that I will probably go with. Not cheap ($89). Many of the roads around here are in poor condition (tax dollars not at work for us) and can be very bumpy so the narrow-wide offers a little more peace of mind, from my perspective anyway. I will post results after installation and on the road experience in a week or two.
 
I installed the Wolf Tooth 52t 130BCD chainring on the outside of the spider and moved the chainring guart to the inside so I could reuse the existing bolts and also to align the chain better with 6-7 cogs where I will spend most of the time cruising. I already like the lower cadence. By comparing gear ratios I found online https://www.bikecalc.com/speed_at_cadence, gear 9 (11t) on 44t chainring is now gear 8 (13t) on the 52t. Gear 6 (17t) is now gear 5 (20t). Gear 1, 52t is marginally higher than the old gear 2 on 44t. I see about a full one gear change across the board. The old chain was too short so I used the largest cog to chainring method to size the chain. It's time to log some miles and try a few short moderate hills to see how it climbs.
 

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I installed the Wolf Tooth 52t 130BCD chainring on the outside of the spider and moved the chainring guart to the inside so I could reuse the existing bolts and also to align the chain better with 6-7 cogs where I will spend most of the time cruising. I already like the lower cadence. By comparing gear ratios I found online https://www.bikecalc.com/speed_at_cadence, gear 9 (11t) on 44t chainring is now gear 8 (13t) on the 52t. Gear 6 (17t) is now gear 5 (20t). Gear 1, 52t is marginally higher than the old gear 2 on 44t. I see about a full one gear change across the board. The old chain was too short so I used the largest cog to chainring method to size the chain. It's time to log some miles and try a few short moderate hills to see how it climbs.
Question: I've got the same bike you do, and bought a Wolf Tooth 52T 130 BCD. Didn't install it yet. Before I try to take my bike apart to do this, would I need the bolts Wolf Tooth sells to fit this on my Rize RX, if I don't want to move the chainring guard to the inside like you did? I ordered a new 52T chainring guard that I'd like to use on the outside.

Also, do you think it would be possible to install a second chainring guard on on the inside too? I'd ideally like to do that to prevent chain slippage. Or would two chainring guards not fit?
 
Any updates on this? I have a Rize RX that came with 44T chainring and I'd like to go up to 48. I would like a narrow/wide chainring with at least the outer guard and it would be nice to have an inner guard too. I'm running out of gear in 9th so about a one gear change would be perfect. How will this affect 1st gear? Do I understand it will actually make first gear easier to pedal? Also does the spider from the OEM setup fit and does it allow you to keep the outer ring guard?
 
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I'm in the process of attacking this myself.
I purchased an inexpensive 130BCD 46T N/W aluminum chainring from Aliexpress as a test as I'm not sure if I want to go even larger at which point I may go for a higher quality one. Current ring is a stock Bafang 40t.
I have the ring and the bolt holes line up and I plan on fitting it this week. Not sure how the guards will work but if you want to add a guard you'll probably need longer bolts. I'm fine with the current setup of a guard on the outside only.
In general... going larger will make all gears a little harder to pedal but add speed. Going smaller adds torque but at the expense of speed and spinning out.
 
The OEM chaingring comes with an outside guard, I don't know if it can be used with a new chainring. It might be part of the sprocket I don't know. Also I plan on going up 4 teeth and wonder if there's a rule of thumb for increasing chain length when going to a new chainring.
 
The OEM chaingring comes with an outside guard, I don't know if it can be used with a new chainring. It might be part of the sprocket I don't know. Also I plan on going up 4 teeth and wonder if there's a rule of thumb for increasing chain length when going to a new chainring.
Well it'll be too small even if it's compatible with your new larger ring. I did not purchase a matching guard as again I'm not sure if 46t will be my ultimate resting place.
As for chain you may need to add a link but that will depend on if the original was properly fitted.
My experience is that you have some leeway.
Think of a bike with a double or triple chain ring... It's sized to the largest ring but works fine with the two smaller ones.
 
I do see that aftermarket chain ring guards are sold but again the issue of which one, what size. etc. Good point on the triple chain rings and yes, my current guard would be useless with a larger sprocket. I don't want to run the sprocket naked, in fact I'd prefer inner AND outer guards
 
I do see that aftermarket chain ring guards are sold but again the issue of which one, what size. etc. Good point on the triple chain rings and yes, my current guard would be useless with a larger sprocket. I don't want to run the sprocket naked, in fact I'd prefer inner AND outer guards
I'm OK with just the stock outer guard as I'm running a single in the rear.
Waiting on new rubber which should arrive by tomorrow... Then I'll throw it up on the lift and see if I can fit the 46t at the same time. My only concern at this time is bolt legnth so I may have to install the stock 40t guard with the larger ring as I don't have different legnth bolts. I'm in no rush so if it ends up being a learning experience I can put it back the stock 40t while I order parts.
With innner and outer I'm thinking your concerns will be bolt legnth and chain line depending on how you stack things.
Clearance of the chain stay could enter the equation as well.
 
Agreed. I did see an outer guard on amazon but it says it's for 42-58 teeth. It must be very tall and then there's the chain stay clearance issue. Will the stock guard work to protect the chain from coming off with a larger chainring? There's a lot of searching to try and find compatible parts for everything but at least with Amazon if it doesn't fit it can be sent back. I don't think I'm going to be able to find an inner chainring guard, oh well
 
I upsized the chainring to a WT 48T on my Ultra powered Frey over a year ago with lengthened chain. Removed the chain guide in the process and never had a problem with the chain dropping. I did buy the WT chainring bolts, but snapped one when torquing, so just reverted to the stock bolts which are heavier duty.

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How many links did you need to add to the chain?
Can’t recall, but rule of thumb is number of extra teeth divided by two. So if new chainring has 8 extra teeth add 4 links.

However being full sus bike I followed Sram’s guidelines which IIRC was to pull the coil spring and let it sit on full sag, wrap chain around largest cog on cassette and chainring then add 2 links.
 
Thanks, I wasn't aware of the rule of thumb. Actually I didn't expect going to a larger chain ring would be a complicated affair whatsoever.
 
Chainguards are not there to prevent the chain from coming off the chainring. They're there to keep pants and such from getting caught between the chain and chainring, as well as getting greasy from rubbing against the chain on the ring. And since the Ultra is set up to have just one chainring and no front derailleur, if your chain even occasionally comes off the chainring, there's something else wrong that should be fixed, not tried to be corrected with a chainguard.

If you're running a wide range sprocket on the rear (I run a 10-50), especially on a full suspension bike, chain length is really important. SRAM's directions work if your rear derailleur is SRAM.

I replaced the front chainring on my Luna Apollo. Since that came with a Wolf Tooth narrow-wide, that's what I stuck with. Clearance with the frame restricted how big I could go. Years and thousands of miles later not a single chainring related problem.
 
I've read that aluminum chainrings wear out much faster than steel but all the aftermarket chainrings I see are aluminum. Point taken on the guard just protecting your pants. I've not had any issues with the chain dropping and I do think the narrow/wide chainrings help
 
Thanks, I wasn't aware of the rule of thumb. Actually I didn't expect going to a larger chain ring would be a complicated affair whatsoever.
I think you're making it a little bigger than it really is.
Follow the basic rule for sizing the chain.. There's plenty of youtubes and again there's a little leeway and not critical down to an exact link count. If unsure go a little longer as it's much easier to remove a link then it is to add.
The Ultra mtb spider doesn't have enough offset to mount an inside guard.
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But if you're not having a problem then there is no need.
And though the guards main purpose is to protect clothing... yes they can aide with chain drops.

Did a bunch of work on my bike today... New wheels, tubes, tires, chain, tensioner and yes a chainring. The test 46t went right on and I reinstalled the 40t guard so the bolts didn't protrude the nut on the backside leaving the threads exposed to damage. My luck I'd bash one on a rock making it a bitch to remove.
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Fyi.. The spider, chainring and guard are all about 4mm each in thickness with the spider sandwich'd in the middle.
Went for a 25mi ride afterwards and I like it. Moved me a gear down making my lower gears more usable and my highest gear almost impossible to spin out... all still feeing easy to pedal without extra motor input. I'm curious to see if my average wh/mi changes.
I just ordered a proper guard... Now it's your turn, get to work!
 
WUZEI: Aluminum
I've seen them on Amazon for about $25 but dirt cheap on Aliexpess.
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Delivery time from order date was 7 days.
I wasn't positive about the T' count and didn't want to invest >$50 for another garage ornament. The reviews are all good so I'm guessing it should last at least a season or at least plenty of time to be sure and source something better. . .
But at this price you could change it with every new chain 🤣🤣

If the material detail is to be believed:
Aluminum 7075-T6
 
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