Cannondale CAADX SE 105 (2018) front brake mount issues

mackeminexile

Hi, hoping someone can help. I'm upgrading the brakes (for the 2nd time) on my CAADX to GRX hydraulics. It seems that the mounting points on the front fork are too widely spaced for a standard flat mount adapter like this: https://r2-bike.com/SHIMANO-Adapter-Flat-Mount-160-mm-140-mm-front by about 3mm. Any ideas? I can't seem to find an alternative online. Is a custom fabriacated piece the only option here?

cletus

If it was me, I'd take a Dremel or similar, and lengthen each mounting hole by 1.5mm

mackeminexile

Looks like it may come to that tbh. Can't contacct Cannondale as there's no option on their site. I've tweeted them but I'm not holding out hope tbh. Cheers

CantGetNoSleep

Are you sure it is a flat mount fork and not a post mount? I had an early CAAD12 disc and one of the brakes was post mount, the other flat mount (although I don't remember which is which). It massively limited choice of groupset - I had to stick to the older non series Shimano 505 / 685 stuff

CantGetNoSleep

https://www.boards.ie/discussion/comment/120117049#Comment_120117049

I took a look at the CAAD12 that I had and it is the 2017 version and it is the fork that is post mount.

In that case you need to find a compatible shifter and post mount caliper. I'm no expert but if I remember correctly - Shimano don't make road post mount shifters anymore.

You'd need to go for the older ones or somehow make an MTB caliper work - but neither of these options will be officially compatible with your GRX shifters.

Someone more knowledgeable can confirm but assuming the easiest and cheapest option is just swapping one caliper - you might be able to make it work just by changing the model of hose.

CantGetNoSleep

And there are also adapters although it is tricky. Fitting a post mount caliper on a flat mount frame is ok I think, the opposite is harder

mackeminexile

Thanks for the input everyone. This shows the fork mounts https://www.cannondalespares.com/CAADX-(2017+)-exploded-diagram/browse_by_model/caadx-2017

It would seem to be post mount but the bike shop guy is saying he can get it to work if we can get it mounted. He's had the wheel in and it aligns etc. It looks like a dremel job as its literally just 3mm that the flat mount adapter is out by. The caliper itself obviously fits the adapter and as I said, lines up perfectly with the disc.

mackeminexile

Just found this https://bikerumor.com/found-a-s-solutions-flat-mount-adapters-for-post-mount-and-is-frames-and-forks/

The 140mm to 160mm seems to be the right one. I'll take the template into the workshop tomorrow to double check before buying.

CantGetNoSleep

https://www.boards.ie/discussion/comment/120117181#Comment_120117181

It does according to the compatibility charts - I think the only road calipers that are available in post mount are the ones on the top right and these are not officially compatible with the modern shifters in the bottom left - see a screenshot from the Shimano manual attached. I could be wrong but this can be fixed with using the correct hose.

But the adapter sounds like it might be a better option

Screenshot_2023-01-16-21-08-15-77_f541918c7893c52dbd1ee5d319333948.jpg

mackeminexile

For clarity, I bought the full upgrade - shifters, hoses and calipers: Shimano GRX BL-RX600 GRX hydraulic disc brake lever bled with BR-RX400 calliper; left rear£148.99Shimano GRX ST-RX600 GRX 11-speed STI bled with BR-RX400 flat mount calliper; right front

Gerry

I gotta say I'm puzzled. My caadx is I think the same.. 2018 with 105. The brakes work fine..

mackeminexile

https://www.boards.ie/discussion/comment/120143899#Comment_120143899

I suppose it depends what you want from them. They were fine for what I was doing while living in the midlands of Ireland and commuting to Dublin, but I moved to West Yorkshire and what I was asking of them wasn't being delivered in any way that made me confident. Some of the hills here are >20% and you come into most villages on a descent so I want more modulation and guaranteed stopping.

Update: I bought the 160mm adapter from AS Solutions in Canada and it worked. Front brake was the only issue - went on fine with the adapter and the difference in stopping power and modulation is night and day.

Gerry

Fair enough. I find the modulation good on mine, but I don't think I've tested them much power wise.

Ya gotta have confidence in your brakes, simple as that..