LiamVanderwood

Hey folks! I'm new to the forum! I hope you're all doing well!
So recently I visited my family back in the states, and during my visit, I stripped down my old Specialized Allez alu frame (at least that's what I think it is, I bought it off of ebay years ago) and packed it to be shipped out to me here in France. At first, I was deadset on slapping a new coat of paint on it with a Sensah groupset and a nice $500 rim set from Elitewheels off aliexpress. But now I'm sorta torn.
Before all this, I was saving for a Carbonda gravel build. I currently have the whole groupset for that; a Sram Force Etap/Eagle Mullet system. I figured I could instead just do a really nice build for this old Allez with the parts I have on hand. The only problem is that the groupset is disc brake and the frame doesn't have mounting points for that.
Would slapping one of those sandwich A2Z-style disc brake converters on the seat stays and buying a disc-compatible fork work? Or should I keep to my original Sensah/Elitewheels plan and call it a future project with the Carbonda/Sram build.



Alternatively, I looked at Magura rim brakes, but the roadblock there is that Magura brakes use a form of mineral oil. If I had gone with Shimano Di2 levers etc. this wouldn't have been an issue, but yeah. So that definitely can't work. The old Sram Red S700's were recalled a while ago, which makes searching for a pair hard (and prohibitively expensive), but also I wouldn't want to do that in the first place because of said recall.

Iride01 

A few years ago I bought all new group set components to put on a old bike that I enjoyed riding quite a bit. I'd previously done the same to another old bike prior to that with very good results. After getting started on it I realized something that I just couldn't get past in my mind. So I went out and bought a new bike and got rid of the other two. Haven't regretted it one bit.

Welcome to BF. Maybe another member will have a solution more to your liking.

big john

Welcome to the forum! There are others here more knowledgeable than I am, but aftermarket disc conversions seem a little risky to me.
There are some pretty strong cable operated rim brakes. Do you intend to use the bike in a lot of wet weather?

LiamVanderwood

Thanks for the welcome! Thankfully here in the southeast of France, rainy weather isn't super frequent. Just a lot of wind.
I'm definitely looking at the Sensah groupset with some nice tiagra rim brakes and Swissstop Black Prince pads in there. It'd be a real nice rim brake setup for my alu Allez.
In a way, it could work nicely to have that as a decent road bike, but I feel like all that might be a bit much for a bike I may not even use once that carbon Carbonda/Sram Force build is finally saved up for, bought, and assembled, ya know?

LiamVanderwood

Hi, thanks for the welcome!
I'd definitely love to buy or setup a full carbon bike, but I'm saving up bit for bit for one at the moment. What do you feel is the best plan for the moment? Stick with the Sensah rim brake plan for my old frame or frankenstein it up with the etap groupset I have on hand?

big john

It would give you a bike to ride in the meantime and could serve as a back up later. Or maybe you could sell it later?

LiamVanderwood

True true! I could always assemble and build up this old frame while I save the tools and various other parts. Then I could sell it for a nice markup (considering the refurbishing it'll receive) to raise some money for the dream carbon build.

Tomm Willians

Interesting you posted this as I was going to do the exact same thing to my 2011 Orbea Terra but ended up buying a Specialized Diverge.
Our LBS has a couple of fantastic mechanics that I trust without question who steered me away from a disc conversion on the Orbea. They stated that the problem was that the conversion kits use mechanical (not hydraulic) brakes and that the mount on the rear seat/chain stay is subject to minor flexing. Then you need to consider a new wheelset (which you did) after awhile it reaches the point of wasted time and money.

DaveSSS 

Converting a rim brake bike to disc is a bad idea, since modern disc frames and wheels are 12mm wider at the rear. You need a disc brake frame. I can highly recommend Yoeleo frames that have exceptional paint jobs and come complete with seatpost and integrated bar/stem. I have two R12 frames, built up with SRAM Force AXS. Rival is the lowest priced electronic 12 speed group.

I've installed SRAM AXS on rim braked bikes, just using Force levers for cable operated rim brakes. Worked great.

Nyah

There's no such thing as even a satisfactory disc brake conversion. Continue w/rim-brake until you can get a frame/fork with thru-axle. Stay away from QR-disc systems. Even well-regarded retailers will try to sell that crap and, a lot of users of QR-disc don't want to admit that it's crap, either. I'm sure this post will stir up some heat. Follow my advice in this post though and you'll save yourself a lot of trouble. QR-disc is already everywhere on the Chinese marketplaces because so many people will buy it without knowing any better. I predict that it'll be on Walmart bicycles soon. There is no downside to thru-axles.

rsbob 

At the least a conversion would be throwing your money away and at the worst you could be risking a front fork failure because your fork was not designed to take on the added stress from disc braking. Discs are wonderful, but I would urge you to either buy a bike designed for discs or better yet, upgrade your existing braking systems and not have to worry about a catastrophic failure.

msu2001la

Rim-to-disc conversions seem to fall into two categories:

1. An exercise in custom frame fabrication and welding by someone who wants to resto-mod a unique vintage bike and/or prove the internet wrong, and has unlimited time, tools, skills and money to throw at a crazy project.

2. A total hack-job of parts cobbled together with screws and clamps, resulting in a rear brake that looks terrible and is highly prone to failure, but sort of works.

Going down road #2 and throwing a $2500 electronic groupset on the end result seems insane to me.

zaje

you are overreacting to non-existing problem.

Camilo

Good quality rim brake calipers with good pads and cabling work extremely well. Yes, I ride both. I wouldn't even consider kludging a disc conversion. There's no need for it.

mstateglfr 

Well at least the over the top claims in you post match the brief rant next to your screen name.

Koyote

Complete and utter nonsense.

aliasfox

My wife's hybrid is a QR disc bike, and the tolerances just aren't there. The dropouts aren't perfectly aligned, and it's always a pain to get the disc to not rub every time I take the wheel out/put it back in. Not a fan. Thru-axle doesn't completely solve the problem, but the tolerances are so much tighter that it's usually a very small matter of backing out the thru-axle half a turn and re-seating the wheel at a (very slightly) different angle. The QR? I've had days where I've ended up realigning the caliper just to get rid of the rotor rub.

Also, given that very few (if any) nicer bikes use a QR with a disc brake these days, those wheels couldn't be used with any other bike going forward.

I just watched the GCN review on the Sensah setup, and it sounds like their two biggest concerns were the mechanical disc brakes and the crank, stating that going rim would likely alleviate many of the braking issues. I'd say if you could get a set of Ultegra/105/Tiagra calipers for the Allez (assuming they work with the Sensah levers), that would be your best bet. If you're not in the wet, and you're riding alloy rims, I don't think you'll have any issues. In fact, I went bombing down a 10mi, -5% hill at 40+mph on my nearly 20yr old Ultegra calipers a few weeks ago, and felt perfectly in control. Had no concerns going down the other side of the mountain (after hauling my butt back up) @ -7% for 5 miles, either - and I'm over 190lbs (87-ish kg).

mstateglfr 

Many hubs have easy conversion caps that allow you to swap between 135mm QR and 142mm TA.

veganbikes

I would get a decent groupset for the Allez or just leave it on the back burner and focus on the gravel bike. I wouldn't just throw cheap parts at it that I didn't already own.

In terms of disc brakes, the bike is not compatible and there is not a practical and safe way to convert it nor would I want to. Until Cane Creek stops making the eeBrakes rim brakes are still alive. Get a nice 105 groupset splurge on some eeBrakes and good pads (the shoes it comes with are nice and stiff) and some good cables and housing and enjoy the bike. Or just skip the eeBrakes but do everything else and bing bing boom you have a perfectly good road bike.

In terms of QRs and disc brakes, that is just silly. QR and disc brakes work fine we know they work fine. Maybe they don't work fine if you decide to not learn how to properly use a QR skewer or have just awful parts but I don't think many folks have had issues. Now saying that I will agree that thru-axles make disc brakes much easier and are a nice interface between wheel and frame and while they take a little longer to install we aren't racing so that doesn't matter. However my QR disc brake touring bike has had zero disc brake or QR issues and I am not a lightweight rider and a light packer either.

bigredgrad01

Don't mess with Allez. It's not built for disc conversion, there's not enough strength in the stays to take the torque. Also every time you pulse the brake, that's a fatigue cycle on alloy.
Allez rim is a great road bike though.

Bald Paul

Couldn't agree more. If you really want a carbon disc brake bike, and you already have a disc brake groupset, a Yoeleo frame (or you can look at the ones from ICAN as well) would give you a good bike at a budget price. ICAN sells some really nice carbon wheelsets as well.