Chain ring tooth selection

You swapped your Specialized 40T chainring to a Specialized 48T chainring. As both of them have threads in the chainring and do not use the 2-piece-chainringbolts, there is no need to hold a part of the bolt from the back whilst you're screwing it from the front.
Now that explains why Specialized chainring/bolts make the chainring swap so easy taken into account very tight tolerance between the ring and the motor chamber...
 
Sounds like RTeremi is using the 48t chainring?


Perhaps @Stefan Mikes can comment, but I recall that I estimated the frame to chain ring clearance for the 52t ring on my Vado. It was so close that I called it as 'does not fit'. It's raining now, or I'd check it again. I laid a thin metal ruler behind the chain ring on my Vado at the center line of the crank. The 52t ring was right on the edge of the frame, though this could could vary by frame and model year so YRMV.
Crap. I think you might be right. I was looking at the down tube clearance and didn't measure the chain stay clearance. I did that and it will be crazy close. Is there a spacer to move the chain ring out a few mm? If you do, does that create an alignment issue?
 
Crap. I think you might be right. I was looking at the down tube clearance and didn't measure the chain stay clearance. I did that and it will be crazy close. Is there a spacer to move the chain ring out a few mm? If you do, does that create an alignment issue?
Spacers are used on mech bikes to correct alignment/shifting issues between the chain ring and the cassette. I don't know if they can be installed on the Specialized Brose motors. If they can adding any spacers may introduce alignment issues you're not experiencing now. This Post shows the crank spider being removed on a Vado between time marks 1:13 & 2:35. It's not clear to me that spacers can be added.
 
Spacers are used on mech bikes to correct alignment/shifting issues between the chain ring and the cassette. I don't know if they can be installed on the Specialized Brose motors. If they can adding any spacers may introduce alignment issues you're not experiencing now. This Post shows the crank spider being removed on a Vado between time marks 1:13 & 2:35. It's not clear to me that spacers can be added.
Because the spider needs a push fit to mate with the spindle, I don't think a spacer will fly - it needs a longer spindle, which is rather difficult in the circumstances, and even that might lead to misalignment, as you say :oops:.

However I have found that a halfway house might be possible, as Deckas do a 50T chainring - see attached.
 

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Having thought about the problem on my Sunday morning ride out :) , it would be possible to achieve the spacing to fit a 52T by wrapping the spindle with self-adhesive shim tape, and then refitting the spider.
 
Project complete: Deckas 52t chainring installed. I have about 2mm of clearance between the chainring and chain stay; my bike is a large so that might help but I don't think frame size should change chainring clearance. I did a test ride applying very heavy pedal pressure to see if it flexed at all and there was nothing. The female side of the crank arm bolts didn't fit between the frame and chainring. I backed them with low tack masking tape to hold them in place before putting the chainring behind the spider then got the thread started and pulled the tape. Then I was able to fit the bolt tool on the back while I tightened them. I installed the KMC x10e chain with 30 links, removed six. I still have the 11-42 cassette on and have good spread with the derailleur in all gears though I will probably never use the 11 or 13. The 15 cog gives me a perfect 28mph at 93 rpms. The 18 cog only gives me 23.6, was hoping for 24.4 or so. I will ride it to work next week and see if the 23.6 gives me all green lights - that's the goal. If it does, I'll keep the 11-42 cog until it wears out and then decide what to replace it with. Note 1: my rear tire is an Electrak 2.0 because I sliced the factory tire a few weeks ago on a road hazard. Note 2: I had to get different chainring bolts from my LBS because the ones I ordered didn't have the cheater slot on the female piece for the tool. I spent $86 and had some fun doing the research and the work. Overall, it pedals more efficiently. Bigger cogs and chainrings create a smoother flow and I have a better chainline because I'm not in the bottom two cogs all the time. Based on tooth count of the cogs only, this system should be 26% more efficient. I'm guessing there's a lot more that goes into it but I haven't done calculus in 34 years so I just did the basic math. I guess I'll find out in about 635 miles.
 
Project complete: Deckas 52t chainring installed. I have about 2mm of clearance between the chainring and chain stay; my bike is a large so that might help but I don't think frame size should change chainring clearance. I did a test ride applying very heavy pedal pressure to see if it flexed at all and there was nothing. The female side of the crank arm bolts didn't fit between the frame and chainring. I backed them with low tack masking tape to hold them in place before putting the chainring behind the spider then got the thread started and pulled the tape. Then I was able to fit the bolt tool on the back while I tightened them. I installed the KMC x10e chain with 30 links, removed six. I still have the 11-42 cassette on and have good spread with the derailleur in all gears though I will probably never use the 11 or 13. The 15 cog gives me a perfect 28mph at 93 rpms. The 18 cog only gives me 23.6, was hoping for 24.4 or so. I will ride it to work next week and see if the 23.6 gives me all green lights - that's the goal. If it does, I'll keep the 11-42 cog until it wears out and then decide what to replace it with. Note 1: my rear tire is an Electrak 2.0 because I sliced the factory tire a few weeks ago on a road hazard. Note 2: I had to get different chainring bolts from my LBS because the ones I ordered didn't have the cheater slot on the female piece for the tool. I spent $86 and had some fun doing the research and the work. Overall, it pedals more efficiently. Bigger cogs and chainrings create a smoother flow and I have a better chainline because I'm not in the bottom two cogs all the time. Based on tooth count of the cogs only, this system should be 26% more efficient. I'm guessing there's a lot more that goes into it but I haven't done calculus in 34 years so I just did the basic math. I guess I'll find out in about 635 miles.
Nicely done. This definitively answers @Stefan Mikes question re the fit for 52t chain ring!
 
Nicely done. This definitively answers @Stefan Mikes question re the fit for 52t chain ring!
I don't want the 52T chainring anymore: The gain from four extra teeth would be marginal but it would further reduce the climbing ability of my Vado. Should I engage more into mountain road cycling for the next warm season, I rather might want to apply a smaller chainring. A 40T one would affect gear-inches substantially compared to the 48T one. It is only pity replacing the chainring requires changing the chain, too. (And that solution cannot remain permanent after I'm back in the flatland).

Besides, I took a close look at the spider and the chainring in my Vado and feel I now understand how the replacement should be done :)

P.S. @Sierratim, I feel miserable now! If I replace the chainring with the one of the fasterestest colour, not only would I need to replace pedals but also the pannier to keep the colours matching! :D
 
I could have replaced the black chainring in 10 minutes, had I Loctite* Blue at hand... (in mail tomorrow). If I wanted to apply the fasterestest colour ring though, I miss the CNW-2 wrench (in mail tomorrow) :)
-------------------
*) For some reasons, Loctite is hard to find here. I've ordered the Würth Blue instead.

1605515149982.png


@TS25, isn't Germany the capital country of cycling? :) To be honest, the red rings came from the U.S.A. even if those were manufactured in China... The black ring and the red bolt-sets came from Germany. Globalisation is good!
 
Project complete: Deckas 52t chainring installed. I have about 2mm of clearance between the chainring and chain stay; my bike is a large so that might help but I don't think frame size should change chainring clearance. I did a test ride applying very heavy pedal pressure to see if it flexed at all and there was nothing. The female side of the crank arm bolts didn't fit between the frame and chainring. I backed them with low tack masking tape to hold them in place before putting the chainring behind the spider then got the thread started and pulled the tape. Then I was able to fit the bolt tool on the back while I tightened them. I installed the KMC x10e chain with 30 links, removed six. I still have the 11-42 cassette on and have good spread with the derailleur in all gears though I will probably never use the 11 or 13. The 15 cog gives me a perfect 28mph at 93 rpms. The 18 cog only gives me 23.6, was hoping for 24.4 or so. I will ride it to work next week and see if the 23.6 gives me all green lights - that's the goal. If it does, I'll keep the 11-42 cog until it wears out and then decide what to replace it with. Note 1: my rear tire is an Electrak 2.0 because I sliced the factory tire a few weeks ago on a road hazard. Note 2: I had to get different chainring bolts from my LBS because the ones I ordered didn't have the cheater slot on the female piece for the tool. I spent $86 and had some fun doing the research and the work. Overall, it pedals more efficiently. Bigger cogs and chainrings create a smoother flow and I have a better chainline because I'm not in the bottom two cogs all the time. Based on tooth count of the cogs only, this system should be 26% more efficient. I'm guessing there's a lot more that goes into it but I haven't done calculus in 34 years so I just did the basic math. I guess I'll find out in about 635 miles.
@ci2i68 It was really good to see this post when I got up this morning - a pioneer spirit :D.
 
I could have replaced the black chainring in 10 minutes, had I Loctite* Blue at hand... (in mail tomorrow). If I wanted to apply the fasterestest colour ring though, I miss the CNW-2 wrench (in mail tomorrow) :)
If you're intending to use your Specialized chainguard with the Deckas 48T chainring it would be a good idea to now lay the Specialized chainring over the Deckas and mark the position of the 4 holes where you need to drill in the Deckas chainring.
 
If you're intending to use your Specialized chainguard with the Deckas 48T chainring it would be a good idea to now lay the Specialized chainring over the Deckas and mark the position of the 4 holes where you need to drill in the Deckas chainring.
Do I need to use the Specialized chainguard at all? Anyway, my gf asks me to use the black ring :)

@ci2i68: Could you tell me the exact outer diameter of the Deckas 52T ring, including the teeth?
 
Do I need to use the Specialized chainguard at all? Anyway, my gf asks me to use the black ring :)
No, you don't need to.

Hmm, so the black ring is the favourite.
What about the blue Garbaruk chainring, did you show it to her or is it on order? 😇

Anyway, always listen to women when it comes to colours.
 
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I might want to use a Garbaruk blue chainring indeed. I only need to search the Forum for your post to find a proper (compatible) chainring there.
P.S. Found!
 
I might want to use a Garbaruk blue chainring indeed. I only need to search the Forum for your post to find a proper (compatible) chainring there.
P.S. Found!
Did you notice Garbaruk offers RD cage for 11-speed shimano in matching blue:

Ouhhh,
I seee new orders coming. :D
 
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Is is the SGS (long cage)? But no, not touching the derailleur unless I'm forced to do it! :D
P.S. Blue pulleys, too? :D
 
Do I need to use the Specialized chainguard at all? Anyway, my gf asks me to use the black ring :)

@ci2i68: Could you tell me the exact outer diameter of the Deckas 52T ring, including the teeth?
No chain guard for me. I can't give you an exact measurement because it is mounted and I can't get a perfect lay with my ruler. Wolf Tooth says their 52t chainring is 216.9mm and my measurement looks to be right about there.
 
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