N+1 strikes again - Carrera Subway 1

[andrewk]

Well I really do NOT need yet another bicycle but couldn't resist a Carrera Subway 1 for £184 in Halfords sale. I was attracted by the combination of fat tyres, rigid frame and wide range gears. Am currently part way through fitting it out, new pedals, rack and bar ends added, mudguards, ergo lock on grips and adjustable stem to come.
Having picked up the bike yesterday afternoon I've only managed a few very short test rides so far. Likes: wide gear range, fat tyres good on soft loose surfaces and also not too knobbly for the road. Dislike: aggressive riding position with handlebars below seat level, hence the adjustable stem on order.
The mechanical disk brakes are problematical though with very poor braking, very much below the effectiveness of v brakes. I guess this is a result of the Halfords build as opposed to an inherent deficiency of the equipment.
Not being mechanically minded Could someone advise me how to set up these brakes. What and how does one adjust them.
Thanks
Andrew

[[XAP]Bob]

Which brakes are they?

[andrewk]

Tektro Novela Black mechanical disk brakes.

[gaz]

Tech docs: http://www.tektro.com/_english/03_suppo ... 730401.pdf

[al_yrpal]

I had Tektro disks on my Subway 2. Brilliant bike with powerful brakes. Suggest you take the pads out and rub them on some medium sandpaper. viewtopic.php?f=16&t=36102&hilit=Touring+for+a+song

Al

[gloomyandy]

You might want to check the cable routing of the discs. My CdF uses TRP mechanical discs and came with the cable routed on the wrong side of the anchor bolt. Moving it to the correct (as specified in the TRP docs), improved braking considerably. If things are still not good you may want to check the type of cable outer that has been used. Disc brakes seem to work much better with a good quality compression-less outer, which may not have been used.

[Brucey]

the brakes won't be bedded in yet. They might well be contaminated in some way and they similarly might not be set up right, but I would not expect them to work at their optimum 'out of the box' as it were.

cheers

[kylecycler]

I got my Subway delivered in its box and built it up myself. The brakes weren't set up very well 'out of the box'. Even after I adjusted the cables and the inner pads, and bedded the brakes in - 20 'medium' stops then 10 'hard' stops, as advised by Tektro - the rear brake worked better than the front, which obviously wasn't right, so I also had to centre the disc rotors in the calipers. Since then they've been excellent.

The cables are standard compressionless gear cables and they're mounted correctly on the frame - Carreras are actually quite sound pieces of kit, as al_yrpal especially will testify (Al's old fondly remembered Subway 2 was what is now the Subway 1, except his had 26" wheels instead of 27.5"). Mine is just a slightly newer version of Al's (2014), but mechanically it's the same as andrewk's, as was Al's.

As well as the tech doc gaz linked to, I found another one, with photos.

http://www.trpbrakes.com/userfiles/file ... Manual.pdf

If a rotor isn't centred, Tektro advise you just to centre it by eye (the front particularly wasn't centred properly on mine) - Page 4, Section 3 in the pdf above - but this is how I did it (if you need to):

Loosen the two bolts that mount the caliper to the adapter so that the caliper is free to slide but doesn't jiggle, then use a 5mm Allen key to move the inner pad in so that when you apply the brake, the rotor is centered, i.e. in line with the join between the two halves of the caliper, parallel with the sides and with equal spacing to either side of the rotor. Then, still holding the brake on tightly, tighten the two bolts. Final tightening of the bolts can be done after you release the brake lever - torque is 6-8Nm. If you don't have a torque wrench, that's 'fairly tight but not too tight,' although I use this simple but clever tool - but if you get one don't use it to loosen, only to tighten, and DON'T STAND ON IT! (I haven't... yet...)

https://www.evanscycles.com/topeak-comb ... 0wodth8L-A

You might need a few goes - when you release the brake lever, the rotor still isn't always lined up right, but persevere until it is. Then adjust the cable using the barrel adjuster(s) at the caliper and/or the brake lever until the outer pad is close but not touching, and use the Allen key to do the same with the inner pad (which involves backing it off from where you set it to centre the rotor). After that, keep the inner pad adjusted with the Allen key; don't just adjust the cable. It might be easier just to centre the rotors by hand/eye without using the brake to 'clamp' the rotor - Brucey could advise - but like I said the brakes have worked perfectly well since.

I use this to clean the rotors - bought it to fix the contacts on the scroller on a phone, only took a few squirts so I had the rest of the can left. I think it's just as good (and a bit cheaper) than 'dedicated' disc brake cleaner (again, though, I'd appreciate Brucey's thoughts - there might be a catch! ):

http://www.halfords.com/motoring/engine ... aner-400ml

I also had to true the rotors slightly and cure squeal on initial application (neither uncommon with discs), but that's another post.

[andrewk]

Thank you for the helpful hints and instructions, will give it a shot. Will be good to get the brakes sorted as its a nice bike and incredible vfm.