2009 Trek 7.3 FX - Convert to disc worth the cost and hassle?


Market Rasen
I have a 2009 Trek 7.3 FX. It is in great condition so I reluctant to sell it. The issue is that I have converted it to a sort of tourer (rack, full mudguards etc.) for light touring (one man tent, one tail pack and 2 rear panniers only). It is fine as it is apart from I'd like it to have disc brakes, as I would like a bit more stopping power when it is loaded up (especially in the wet) and I am concerned about rim wear. A carbon fork might be an improvement too as it will make the ride slightly less buzzy. I can get a new wheelset for about £160 (Shimano hubs + Alex rims). Spa cycles also do a good range of wheelsets for £180. It also might be wise to get a 36 hole rear and a 32 hole front (my current wheels are are the OEM Bontrager Nebula 32 hole front and back). My intention is run 700c 28-32 size tyres (most likely 32). The current levers will be fine for disc brakes it seems (obviously mechanical ones). I will need some rotors, calipers, new cables and some disc brake adapters. Will mechanical discs be a noticable improvement over v-brakes? If costs are prohibitive, maybe I could just convert the front and leave the rear as a v-brake. I might stumble across some decent wheel(s) with rotors and calipers on fleabay or similar to make it a bit more cost effective. So would do I do? Keep it as is and put up with it and replace the wheels when they are worn out, convert fully / partly to discs or sell the bike and buy something more suitable?


Legendary Member
Doesn’t the frame itself need to support disc brakes? Which yours doesn’t presumably? I don’t know if you could change the fork to a disc brake one?

So maybe you’d be better off selling it while used prices are still through the roof and get a disc braked bike


North Shields
What @vickster said.

I'm not convinced about disc brake adapters. I don't see how they can cope with the stresses involved without seriously damaging a frame that wasn't built with them in mind. Or worse still, just pinging off and doing nothing when you need them.

I could be totally wrong about this, but it's something I've always thought.


The frame wasn't designed for disk brakes, it will be a bodge to try to fit them. Either it won't work well and they will not work properly or you'll end up with an unsafe bike.
  • Like
Reactions: DSK


Slippery scientist
I have converted my steel-framed MTB from cantilever to discs with an A2Z Universal disc brake adaptor. It has snapped the frame twice and I died four or five times just last week. Oh, wait... no, it’s fine, the brakes work fine and I’m OK.

It’s not plug-and-play and needs a bit of fettling to fit and line-up but it’s a decent bit of kit.


Flouncing Nobber
Properly set up theres no reason why rim brakes can't be very powerful. A play with cables and brake blocks is liable to yield decent results, but bodging discs onto a frame with adaptors etc is liable to be no better than you can achieve by optimising what you already have.

@All uphill sums it up perfectly in their post.


Senior Member
It’s been mentioned and I’d have thought if the frame was not designed for it then avoid. If you want discs then get a bike that has them.

I’d also echo the above about fettling you rim brakes to ensure you’re getting the best of them, (often overlooked and possible the incorrect brake pads could be in place if you get the bike of someone whose been swapping wheel sets etc)


Grumpy Old Barstool
Oop North (ish)
My own personal preference is avoid cable disc brakes like the plague far too high maintenance, only ever consider hydraulic disc brakes, at which point they become the mutt's nuts, never mind the luddites who still prefer 'Brake Blocks' so 19th century.


Market Rasen
Thanks peeps. I think I will just leave the bike as it is. The consesus of opinion (including Spa Cycles) is that it is not economic (given that the frame does not have the mounts) for what little extra braking that mechanical discs will give.
Last edited:
Top Bottom