# 2020 Cannondale Cujo 24



## TimTucker (Nov 9, 2011)

Picked up the new Cujo 24 over the weekend from REI. With as tight as availability has been lately, I figured $50 less than retail ($500 vs. $550) was worth giving it a shot:








Weights:

Front QR skewer: 60g
Replacement: Spare from a Koozer hub: 40g

Rear QR skewer: 66g
Replacement: Spare from a Koozer hub: 45g

Rotors: 126g each
Replacement: Ashima Ai2 clones: 75g each

Bottom Bracket: 335g
Replacement: Ti bottom bracket off Aliexpress: 144g

130mm Cranks: 541g
Replacement: Spawn 102mm square taper cranks w/ Neutrino components oval 26t 64 BCD chainring

Velo Saddle: 308g
Replacement: Tioga D-Spyder S-Spec Pivotal: 145g

Seatpost: 295g
Replacement: Nylon pivotal post: 95g

Assorted pile of reflectors: 91g
Replacement: (eventually I'll put on a few grams of reflective tape on the rims)

Pedals: Wellgo: 276g
30mm / 25.4 clamp stem: 146g
Replacement: Wren 40mm

Tektro Mechanical disc brakes: 335g (front only: lever, cable, caliper)
Replacement: (planning to get another set of Tektro HD-M745 4 piston hydraulic brakes once they come back in stock)

25.4 handlebar: 277g
Slide on grips: 70g
Replacement: Protaper Junit

Fork (400mm A2c): 711g (with disc brake adapter / mounting bolts, & crown race)
Replacement: Fox F29 FIT RLC 100 (had it on an old 29er) -- serving as a stand-in until I come across a sale on one of the 120mm or 145mm Junit 24" forks

Dork disk / spoke protector: 31g
Removed

11-34t Sunrace Cassette: 350g
Replacement: Shimano 11-42T 10 speed: 431g (may replace this with a Sunrace CSMX3 at some point)

Tourney TX Derailleur: 324g
Replacement: Shimano Deore 10 speed: 324g

8 Speed Shimano grip shifter
Replacement: 10 speed Shimano Saint shifter

8 speed chain: 293g
Replacement: KMC 10.93 10 speed chain: 257g

Rim strips: 26g each
Replacement: (will use some tubeless tape after I rebuild the wheels)

24x2.6 Kenda Slant Six tires: 770g each
Replacement: CST Fringe 24x2.8: ~670g each (both came in higher than the 620g spec)

24x2.4-2.75 Kenda tubes: 277g each (these appear to be their downhill rated tubes)
Replacement: REI Co-op 1.9-2.125 Tubes: 165g each (spec was 158g)


With the changes so far, it's dropped from ~24 lbs to a little under 23 lbs.

Have some CST Fringe 24x2.8 tires on the way along with some lighter hubs -- should shave off ~200g for tires, another 200-250g for the hubs, and another 40g to replace rim strips with tape. Will weigh the tubes when the tires come in, but I'm guessing I can probably find drop a little there too.

One thing I did confirm was that the seat can't be all the way down with the Tioga saddle -- even with only a 50lb rider, there's enough flex in it that it was rubbing on the tires when he hit bumps.

For those curious how 26" tires might fit, I did a quick test with the tires off a '92 Trek 830.

Front with a 26x2.5" Surly Extraterrestrial (Not too surprising that it fit, given that it measured 400mm A2C, same as the stock fork on the Trek):








Rear with a 26x46c Surly Extraterrestrial:















A little surprised that it fits 26" tires better than my 26er!

First ride out on trails today went well -- even with the rigid fork he went straight after some log pile features and cleared them with no problem.

All of us are still trying to figure out how this jumping thing works, though -- no one in the family has quite figured it out yet. His younger brother was with us on his "new" mullet Yoji and seems to think that the secret is just quickly alternating between sitting and standing up.


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## thchen (Sep 24, 2013)

Do you mind sharing the link to the AliExpress TI BB? I recently bought a short (520?mm) cf handlebar and the lightness was ridiculous vs the OE steel bar they chose for the Cannondale 20”. Thanks.


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## TimTucker (Nov 9, 2011)

Here's one of the sellers we ordered from:
https://www.aliexpress.com/item/32952847076.html

Note that if you just search for "titanium bsa" there are a lot more sellers that show up. There seem to be 2 main brands: ACRZ and Muqzi.

The Muqzi ones seems to all come with ceramic ball bearings and were offered in a few more spindle lengths. For the 119mm length, the ACRZ ones have a lower weight spec (148g vs. 170g advertised -- mine came in at 144g).

For reference, here's the Muqzi:
https://www.aliexpress.com/item/4000014613361.html

I went with the 119mm spindle steel bearing version because I wasn't sure the potential tradeoff of durability was worth it vs. the extra cost.


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## TimTucker (Nov 9, 2011)

Tried something crazy this morning and swapped in the front end off an old 29er:








Put a short video of a test ride up on Facebook:



__ https://www.facebook.com/tim.tucker.52012/posts/10160257028893332



Short summary -- while it was technically rideable, he wasn't a fan of the resulting 62.5 degree head angle and overall handling.

It looks like the stock 24" front wheel does fit and the overall length isn't that far off from the Junit fork (just under 67 degree head angle), so I'm going to see if I can get him to try riding it that way once he calms down a bit. (He was pretty insistent about just putting everything back the way it was)


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## Darth Lefty (Sep 29, 2014)

Nylon seat post? huh, thanks for sharing that, it might go well on little girl's Spawn


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## TimTucker (Nov 9, 2011)

Darth Lefty said:


> Nylon seat post? huh, thanks for sharing that, it might go well on little girl's Spawn


They're nylon with what appears to be an aluminum insert running along the upper portion.

I'd posted a thread about it with some photos when we first got them:
https://forums.mtbr.com/families-riding-kids/nylon-seatposts-1091537.html

The main downsides:
- The reinforcing at the top means the minimum saddle height is about 1/4" to 1/2" or so higher than you can get with the Spawn posts.

- They're not particularly long (150mm), so you're limited on how far it'll extend.

If you need something in the intermediate range between needing the seat fully slammed (Spawn post) and needing it extended further, they work great.

You might also be interested in this recent find -- once you do get to the point of needing a longer post, Cult makes a layback pivotal post that you can reverse to mimic a steeper effective seat angle -- useful if you've slackened things up a bit from adding a longer suspension fork:
https://cultcrew.com/products/counter-layback-post

From talking with my son a little more today, he expressed some concern that he could no longer pedal straight over some of the features in our backyard and was annoyed that he had to keep his pedals level to clear them. Sure enough, the ground clearance was nowhere near what he's gotten used to on the Cujo 20 with Junit fork & 102mm cranks.

Looks like we'll be sticking with 102mm cranks for the time being and based on measurements with the 29er fork I put on there as a test, we'll probably need at least the 120mm Junit fork (475mm A2C) to get the clearance that he's used to.


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## TimTucker (Nov 9, 2011)

Here's the bike looking a little more normal with the shorter cranks and 29er fork with 24+ wheel -- current geometry should be pretty close to the 120mm Junit fork:


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## TimTucker (Nov 9, 2011)

Updated the original list with a few more of the weights / component swaps -- still more that we can and will do eventually, but we're currently just under the original 24 lb weight.

Not too bad given that we've lost rotating mass and gained a suspension fork, a wider range 10 speed drivetrain, and a water bottle cage.


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## Darth Lefty (Sep 29, 2014)

TimTucker said:


> - The reinforcing at the top means the minimum saddle height is about 1/4" to 1/2" or so higher than you can get with the Spawn posts.


I don't know what Spawn has now but we got a used Banshee. It has a completely conventional adult scale single bolt set back seat post with a lot of stack and it's got too much length as well


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## TimTucker (Nov 9, 2011)

Darth Lefty said:


> I don't know what Spawn has now but we got a used Banshee. It has a completely conventional adult scale single bolt set back seat post with a lot of stack and it's got too much length as well


Here's a comparison between one of the current Spawn pivotal posts vs. the nylon post with red lines added in to show how far down each will insert:


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## dkelley383 (Jun 9, 2005)

Just ordered this bike for my son. I plan on replacing the grip shifter, could you tell me if the grips are a standard size or are they are smaller kids version?


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## TimTucker (Nov 9, 2011)

dkelley383 said:


> Just ordered this bike for my son. I plan on replacing the grip shifter, could you tell me if the grips are a standard size or are they are smaller kids version?


Stock bar is standard 22.2mm.


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## dkelley383 (Jun 9, 2005)

TimTucker said:


> Stock bar is standard 22.2mm.


Thanks!

Sent from my iPhone using Tapatalk


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## TimTucker (Nov 9, 2011)

Just ordered a 145mm Junit fork from Hayes (they've got a 20% off sale right now for Black Friday).

Trying to decide on a front hub to use now.

I see Amazon has Shimano SLX HB-M7110-B hubs for ~$30, but the I'd need a centerlock rotor or an adapter to 6 bolt.

Anyone have recommendations for an adapter or for a cheap / light 6 bolt boost hub for 28H?


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## Rosco B (Mar 2, 2021)

Hi there.

Sane bike I have for my son. I'm trying to fit tapered 1 1/8 forks. The original forks are straight tube. I take it this wont work? Looks like a reducer thingy in the stearer tube but I'm a novice so not to sure.


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## rton20s (Aug 27, 2010)

I don't have one of the Cujos, but it looks like it might use a ZS44 zero stack headset top and bottom. If that is the case, you can probably keep the upper headset as is (ZS44/28.6) and replace the bottom with an external cup EC44/40 in order to fit the tapered fork. This could also be an opportunity to replace the upper and lower if you were looking for a nice, sealed upgrade. 

Tim might be able to confirm the actual headset standard used.


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## Rosco B (Mar 2, 2021)

That's sounds promising, just found this do you think it will work? *Brand-X Headset - 44IETS - Sealed *ZS44/28.6 I EC44/39.8.

I have so far removed the grip shift and replaced with a shimano shifter which as so much better. Also new riser bars 680mm instead of stock 580mm. The bike feel way more stable, I was thinking of new BB any recommendations? Hope to get the forks on now ?


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## rton20s (Aug 27, 2010)

I don't have one of the Cujos, but it looks like it might use a ZS44 zero stack headset top and bottom. If that is the case, you can probably keep the upper headset as is (ZS44/28.6) and replace the bottom with an external cup EC44/40 in order to fit the tapered fork. This could also be an opportunity to replace the upper and lower if you were looking for a nice, sealed upgrade.

Tim might be able to confirm the actual headset standard used.


Rosco B said:


> That's sounds promising, just found this do you think it will work? *Brand-X Headset - 44IETS - Sealed *ZS44/28.6 I EC44/39.8.
> 
> I have so far removed the grip shift and replaced with a shimano shifter which as so much better. Also new riser bars 680mm instead of stock 580mm. The bike feel way more stable, I was thinking of new BB any recommendations? Hope to get the forks on now ?


That does look like it would work if my assumptions are correct. Hopefully Tim will confirm the size, or you can measure yourself with a micrometer.


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## TimTucker (Nov 9, 2011)

Yes, the Cujos are all 44mm headtubes, so an external cup headset will work for a tapered fork.


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## Rosco B (Mar 2, 2021)

Great I've just ordered one. Brand x only 18.99. I will post some pics when done. Thank you guys very helpful.👌


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## Rosco B (Mar 2, 2021)

All done worked perfectly. Thank you for the help. What size is the bottom bracket? Thinking of replacing as its 3 years old now.


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## TimTucker (Nov 9, 2011)

Some more weights for those that are interested:

Rims
490g

Rear hub
441g

Front hub
233g

Had the wheels rebuilt on some lighter hubs and we're down to 960g rear / 861g front. Rims were a bit heavier than I'd hoped -- about 100g each heavier than the Junit wheelset.

When I tore things down, the CST Fringe 24x2.8 gave me a terrible time getting the bead unseated -- based on just how stuck they were, I figure it may be a safe combination to try running tubeless (currently mounted and seems to have held air well for a few days at higher pressure -- will see how it goes once we reduce down to a more normal pressure and start riding on them.


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## TimTucker (Nov 9, 2011)

Rosco B said:


> What size is the bottom bracket? Thinking of replacing as its 3 years old now.


Bottom bracket is 68mm BSA.


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## zward (Mar 16, 2021)

*


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