billyfreezer

I finally went carbon with a Cannondale synapse disc 105 2019. I had a flat in my rear tyre so went to change it. First time with a thru-axle (non-quick release). When I went to put the thru-axle back in, it wouldn't screw up.

Uploaded a video to demonstrate, with the rear wheel removed for better visuals. Apologies for the camera work.
Ahh looks like I can't post URLs, d'oh.
Let's try this: youtu.be/Tw75_qhF34w

I was firmer with pressing the chain/seat stays together when I had two hands, but no luck. Am I missing something? Looks like it should just screw in. Have the threads been stripped? Note this is the first time I changed the inner tube, never actually been able to tighten it up so I couldn't have over-tightened it!

Bill Kapaun

I don't do videos, but useful info would be-
Brand & Model of the hub.
If Shimano, there's probably a tech doc/exploded view that would allow someone to know EXACTLY what you have.
It might even be "educational enough" to help you figure out what's going on?

EDIT- You do know how the Quick Release works?

AnkleWork

Maybe get someone with more experience with threaded fasteners to look at it and demonstrate usage.

alcjphil

The OP did specify that their bike has Thru axles, not quick release axles

alcjphil

Well, I tried the provided link and got this message:

Private video
Sign in if you've been granted access to this video
SIGN IN

Bill Kapaun

The term "ratchet lever" made me think of a QR lever that he was trying to spin on.
I'm just not familiar enough with these for a red flag to fly.
Maybe someone can watch the video?

alcjphil

I tried, no joy

billyfreezer

Thanks for looking guys. Not sure why the video says it's private as it's public. Here's the long-form URL.
youtube.com/watch?v=Tw75_qhF34w&feature=youtu.be

The thru-axle - writing on it shows:
18G2 QR51x-12-160-P1.0-16.5

The thread it is screwing into is an M12x1 single-lead pitch.

In appearance it is very similar to this one, but with different dimensions.
cannondalespares.com/Cannondale-Synapse-Carbon--Treadwell-Neo--Topstone-Ratchet-Lever-Maxle-100x12-125mm--K83038/product_detail/3-43245


Yup, not a quick-release lever. Familiar enough with those. First time using threaded thru-axle so wandered if I was being a right idiot with it. From what I could see, it seemed like a simple unscrew/screw on job, no tools required.

Hubs Formula RX-512 12x100 front, RX-142 12x142 rear

WizardOfBoz

I pasted the url into my browser and it worked just fine.

It looks like your axle isn't long enough. Perhaps the rear dropouts spread out (but its a cf bike). When you put the actual wheel into the dropouts, do the dropouts touch the wheel locknuts, or is their space? What is the measured interior (locknut to locknut) dimension of the frame? Perhaps the threads at the tip of the axle are stripped. How do those threads look? If you take the axle and thread it into the drive side nut in reverse (from the outside of the bike) how do the threads feel? Are you sure you have the right axle (didn't swap inadvertently with another bike)? Can you engage the axle threads by pushing the dropouts together?

Sorry if these suggestions are idiotic, but I'm trying to figure out the issue. For sure, it looks like the axle is going in all the way but the threads aren't engaging.

freeranger

Also looked at the video, and like WizardofBoz, having a hard time figuring it out. Did the dropouts "spread" wider when the wheel was removed? Sure looks like the axle is too short to reach the threads on the other side, and I'm guessing that you are using the same axle that came out of the rear wheel (front axles are usually shorter than rear axles). Pls let us know what the problem was when you get it back together--inquiring minds want to know!

billyfreezer

Thanks for the help all. Basically correct. The dropouts screw had loosened, so whenever I started screwing the thru-axle in, the dropouts had a 'give' to it, so the threads wouldn't engage. Simply tightening the screw up solved it. Hopefully they won't continue to come loose.