Chainring replacement how to ..

[Mike Smith]

There's been a bit of discussions on the chainring sizes and replacements so I thought I'd document the procedure for the folks who are unsure what to do ..
These are the bits that I bought, I stuck with Praxis having the Wave Tech, as the original chainring had this..

1. Praxis Works MTB Wave Tech Chainring LINKY
2. M8 Single Chainring Bolts LINKY

Tools required 4mm & 6mm Allen Keys
Loctite Thread Lock
PVC Tape
Flat scraper

First off with a 4mm allen key undo the chain guide don't remove the bolt.
Then with a 6mm allen key remove the chainring bolts, and slide the chainring off the spider, it's a bit of a faf but it'll come off.


Old and the new


The original chainring had threaded inserts, replacement ones do not hence new chainring bolts


You'll need to use some tape to hold the nuts into the chainring to make it easier locating the bolts once fitted.




New chainring now in place and ready for the bolts


Here's the scraper holding the back of the nut whilst tightening the bolt, with threadlock applied to the threads of the bolt first. Nip up as tight as you can further tightening will be done later once the chain is on and you can then get more leverage.


On the Praxis Wave Tech rings the chain has to go on a specific way


Finally nip up the bolts and don't forget to position the chain guide and retighten!

Here's how the 36T ring looks with the original chain.


Time to do this around 30 mins

 

[Gogogordo]

Nice job!
Great post!

 

[SteveVentoux]

Thanks Mike, really helpful.

 

[Kimmoi]

M8 Single Chainring Bolts; right lenght is that 6,5mm?

 

[Mike Smith]

Yes 6.5mm overall length.

 

[Stumpy]

Thanks Mike - great write up.

One question though - you say the the chain has to go on a specific way.... what do you mean?

 

[Mike Smith]

On Praxis Wave Tech the chain outer link has to align with the marks on the chainring ..

 

[strugla]

Great info, could I suggest that you make shure that the chain isn't too short if you increase the chain ring size, especially important with full suspension rigs.

 

[Tori]

Great info, could I suggest that you make shure that the chain isn't too short if you increase the chain ring size, especially important with full suspension rigs.

I asked in the other thread, have people kept the same chain length - stock was 116 links. I have just put on a Wolf Tooth 36T chainring, and I'm not sure if I should fit up a longer chain. I have a full length 118 link chain that I could use. Any advice?

 

[Mike Smith]

Mines fine with the stock chain, could always use a pair of quick links??

 

[Tori]

Mines fine with the stock chain, could always use a pair of quick links??

Yeah good point - I'm just not sure what's too tight with a chain. I haven't taken it for a spin today, but I have moved up and down through the gears and it shifts sweet and in the big cog there is still a bit of flex in the chain, I think it could be OK as is.

 

[Stretch]

Yeah good point - I'm just not sure what's too tight with a chain. I haven't taken it for a spin today, but I have moved up and down through the gears and it shifts sweet and in the big cog there is still a bit of flex in the chain, I think it could be OK as is.

I changed mine to 36T a few weeks ago and have not had any issues with the standard stock chain (no additional links added).

 

[Mike Smith]

I changed mine to 32T a few weeks ago and have not had any issues with the standard stock chain (no additional links added).

Do you mean from 32T stretch?
As our stock ones were originally 32T and now we are 36T

 

[Mike Smith]

Yeah good point - I'm just not sure what's too tight with a chain. I haven't taken it for a spin today, but I have moved up and down through the gears and it shifts sweet and in the big cog there is still a bit of flex in the chain, I think it could be OK as is.

Do you use the rear big ring much Tori ? as I still find Im not utilizing the 2 top end rings still

 

[Stretch]

Do you mean from 32T stretch?
As our stock ones were originally 32T and now we are 36T

Yes 36T, sorry about that, have corrected.

 

[Mike Smith]

Do you find you can out pedal it still?

 

[strugla]

My only experience with this is with clockwork bikes but the potential hazard to your wallet remains the same with an ebike.

Put your bike in it's 2nd biggist cog at the rear and let out all of the air from your shock. Now flip the bike upside down and collapse the suspension (simulating a big hit) and whilst pedaling shift to the largest cog. This will replicate the maximum chain growth that your bike will experience. If your happy with what you see and there is no danger to your mech, chain or mech hanger put the air back in the can and you're good to go. If not then you will need to replace or lengthen the chain by any of the methods above.

Riders with coil spring suspension could unbolt one end of the shock.

Re reading this it seems a bit of a lecture but I once had to lash up a bike as a single speed to get home , (chain was too short). Hmm did I just invent a new market sector, SS ebike?

 

[Grasshopperaggy]

Thanks for this thread. I to am needing to replace my 32t standard chain ring. Just one question. I like the look of the praxis chain ring u used her Mike but I fancied replacing mine with this one.
Race Face Narrow Wide Chainring - 104 BCD | CHAINRINGS | Evans Cycles

Or this

Hope Single Downhill Chainring - 104mm BCD | CHAINRINGS | Evans Cycles

Should this work. Sorry if it's a bit of a oblivious question.

 

[Mike Smith]

Race Face should be fine as its suitable for 11 speed.
Hope one isn't.

 

[bigborett]

Tried my Ethirteen 36tooth today. Seemed really good. missed a couple of changes, but I'll adjust that.

The Ethirteen's are nice and thick for an alloy sprocket also. That was what made the decision for me, that and I could get it in red.

 

[Tori]

Tried my Ethirteen 36tooth today. Seemed really good. missed a couple of changes, but I'll adjust that.

The Ethirteen's are nice and thick for an alloy sprocket also. That was what made the decision for me, that and I could get it in red.

Andrew, just back the B-Tension screw off a little bit on your rear mech. Going from 32 to 36T you have increased your chain tension. I found just backing off a bit, the shifts are super smooth and crisp all through the cassette.

 

[bigborett]

Andrew, just back the B-Tension screw off a little bit on your rear mech. Going from 32 to 36T you have increased your chain tension. I found just backing off a bit, the shifts are super smooth and crisp all through the cassette.

I did do that Tori, may just have to tweak it again.

 

[Tori]

I did do that Tori, may just have to tweak it again.

Pop the bike on a stand and adjust it and play with the gears as you do adjustments . . . you should find the sweet spot quickly that way.

 

[Dajafe]

Thanks Mike, a great write up and just what I was looking for.

But...I have the stock pedals (SBC-54 - Bennies?) and cannot get the 32T ring over it. Do you need to remove the pedals?
I cannot shift the little blighter - any advice?

Up to that point it went like clockwork.
Looking forward to getting the 36T fitted.

 

[Grasshopperaggy]

When I removed my stock pedals the day I picked my bike up they were on very tight. I did not think they were going to shift. I would guess they will have to come off to remove ring.

 

[Dajafe]

A bigger spanner it is then... thanks

 

[bigborett]

Thanks Mike, a great write up and just what I was looking for.

But...I have the stock pedals (SBC-54 - Bennies?) and cannot get the 32T ring over it. Do you need to remove the pedals?
I cannot shift the little blighter - any advice?

Up to that point it went like clockwork.
Looking forward to getting the 36T fitted.

Yes you will have to take the pedal off. Unless maybe if you run clipless. Remember one pedal is right hand thread while the other is left hand.
Even with the pedal off I really had to juggle to get the ring on. It will depend on the internal size and shape of your new ring.

 

[jxj]

Thanks to all for the tips in this thread! I put a Raceface 36T on my Turbo Levo Carbon Comp. The factory 32T slipped off and the 36T went on with a little bit of puzzle solving skills. Never had to break the chain or remove the clipless pedals. I put steel chainring bolts on and used blue threadlocker. I used some masking tape to hold the backing bolts in while I got the ring aligned. I really like the 36T much better. I was spinning out downhill with the 32 and now seem to be hitting about 110 cadence at 30mph. I can live with that. On the low end on high teens slopes I'm going to be losing traction on dirt before I need a lower gear than the stock cassette and a 36T so no loss for me there. Very happy with this setup.

 

[Norange]

Put a 36T on mine tonight, will be giving it a spin tomorrow. Looks nice tho

 

[jxj]

[
What Brand is that? I like the colors. Good match with the purple blue color changing Carbon Comp model. I put a Racefacce on mine and really like the 36T better. I Would like to source a steel one if someone knows of it please chime in?

One note likely known by all but me, is that the jockey pulley on the Sram rear mech is narrow wide. Never had one like that before on all my Shimano stuff but this is my first sram rear mech. Gave me some fits as I couldn't source the strange noise and it has slipped 1 tooth and was riding high. No damage or problem but likely won't shift if it's off and makes an ugly noise.