Road Bike Brake Performance...?

Neil_aky

Since moving to a road bike from my Mountain Bike styled hybrid with 'v' brakes I have been really disappointed in the braking force. It is a Triban 3 with the original BTwin calipers. I changed the brake shoes to XLC parts as I bought the same make for my 'v' brakes and they were outstanding; however, they have made little / no difference on my road bike.

As road bike levers and callipers seem to have similar geometry and therefore leverage I am guessing the best way to improve braking force is the brake shoe type...? Or am I missing something?

Is there anything I can do or is it just that 'v' brakes are that much better than road callipers?

I know my Triban 3 has quite heavy wheels - the physics would suggest that this could have an effect on braking performance - is this a significant factor in braking performance?

MountainMonster

All road brakes are pretty crap :d

lotus49

The real problem with braking on a road bike is that the centre of gravity is much higher than the front tyre contact point. Consequently, too much front braking force and you're over the handlebars. It doesn't really make a huge difference what sort of brakes you use as none of them can change the fundamental geometry of the bike.

Pituophis

Coming from mtb'ing myself, I was initially scared witless by the lack of braking performance on road bikes :shock:
You soon get used to it though, 'till you have your first really wet ride, then you remember all over again

Anonymous

Pituophis wrote:

Coming from mtb'ing myself, I was initially scared witless by the lack of braking performance on road bikes :shock:
You soon get used to it though, 'till you have your first really wet ride, then you remember all over again

Guessing you did not have V brakes though did you?

If the OP had rim brakes then I would have thought the same type of braking is possible on a road bike?

BelgianBeerGeek

All other things being equal (road surface/conditions, tyres etc) V-brakes should be more powerful than calipers.

Caliper brakes vary though, and your Triban may have generic unbranded brakes. As with most things, if you upgrade you should see better performance.

As has been said, you will get used to it, and adjust your riding accordingly.

t4tomo

Biggest limiting factor on a road bike braking is the fact that there is only 2 pieces of rubber covering an area of approx the size of a penny in contact with the road.

pdw

Not really. On a dry road, you'll go over the bars before your front wheel runs out of grip.

marcusjb

^^ definitely

Any decent caliper brake with decent pads, newish cables, that have been set-up properly will be able to lock either wheel up way before the tyre gives up (on a dry clean road).

One thing to try is to use a bit of degreaser on your rims - you may have wiped the rims down with an oily rag or something? Doesn't take much grease on the rim and your performance will be somewhat compromised.

lotus49

I forgot to add to my post above that pads make a huge difference. Generic cheap pads are almost always rubbish but replacing them with something better is cheap and easy.

Neil_aky

Any recommendations for brake pads?

southdownswolf

Swissstop Flash Pro green or Kool Stop Salmon, assuming aluminium rims.

Bordersroadie

I agree that the pads make a tremendous difference. I changed to Swissstop greens and found a huge improvement especially wet braking.

However, different calipers also vary widely in stopping power. My wet bike uses deep drop Tektro R539s. My dry bike, Ultegra. Same pads, same aluminium rims. Massive difference, even though the Tektros work well with the green pads, the Ultegra brakes offer way more power and smoother modulation.

To the OP, try new pads first but almost defintely you will get another big step improvement of you get better calipers than the B-Twin ones.

Neil_aky

Where does the extra power come from? Callipers look similar in geometry so would appear to offer similar force on the rim - am I missing something?

I know the B-Twin callipers are basic but they are solid enough and look similar geometry to more expensive callipers - I assumed the only gain would be lighter parts...?

Bordersroadie

Neil_aky wrote:

Where does the extra power come from? Callipers look similar in geometry so would appear to offer similar force on the rim - am I missing something?

I know the B-Twin callipers are basic but they are solid enough and look similar geometry to more expensive callipers - I assumed the only gain would be lighter parts...?

Good questions. My Ultegra get better performance from a few areas. Compared to the Tektro (designed for mudguard bikes) they are shallower drop by some 10mm and therefore more able to convert lever effort to the rim since the fulcrum of each caliper arm is closer to the pad. Secondly, the quality of the materials and design is better, so there is less flex in the arms and around the pivot points due to closer tolerances in design and manufacture and better quality bushings and pivot surfaces. My Ultegra brakes actually replaced some bottom of the range Shimano shallow-drop brakes which looked almost identical in terms of dimensions and design, but I was amazed at the improvement in performance. The bonus is the Ultegra are lighter but the important gains for me are in the very real performance advantage.

Don't underestimate good engineering in road bike brakes, because if you imagine an 85kg rider/bike combo travelling down a 10% gradient at 40mph, braking hard, the forces acting on the caliper are huge, they're having to resist being ripped off their mounting points and having their arms bent in half. The opportunity for higher quality, more accurate engineering to give better performance in this area is massive.

When I'm flying down a big downhill and need to slow or stop, such differences are very obvious.

I'm now thinking of replacing the Tektros with Shimano R650 because I have read that they're Ultegra quality and way better in performance. Also worth mentioning is that the Tektros are looking shabby after only one winter, rusty pivot bolts, springs etc, and I suspect are deteriorating quicker in terms of pivot wear and therefore braking performance.

Frank Wilson

It just may be that you are going faster on your road bike than you were on your MTB

declan1

Bordersroadie wrote:

Neil_aky wrote:

Where does the extra power come from? Callipers look similar in geometry so would appear to offer similar force on the rim - am I missing something?

I know the B-Twin callipers are basic but they are solid enough and look similar geometry to more expensive callipers - I assumed the only gain would be lighter parts...?

Good questions. My Ultegra get better performance from a few areas. Compared to the Tektro (designed for mudguard bikes) they are shallower drop by some 10mm and therefore more able to convert lever effort to the rim since the fulcrum of each caliper arm is closer to the pad. Secondly, the quality of the materials and design is better, so there is less flex in the arms and around the pivot points due to closer tolerances in design and manufacture and better quality bushings and pivot surfaces. My Ultegra brakes actually replaced some bottom of the range Shimano shallow-drop brakes which looked almost identical in terms of dimensions and design, but I was amazed at the improvement in performance. The bonus is the Ultegra are lighter but the important gains for me are in the very real performance advantage.

Don't underestimate good engineering in road bike brakes, because if you imagine an 85kg rider/bike combo travelling down a 10% gradient at 40mph, braking hard, the forces acting on the caliper are huge, they're having to resist being ripped off their mounting points and having their arms bent in half. The opportunity for higher quality, more accurate engineering to give better performance in this area is massive.

When I'm flying down a big downhill and need to slow or stop, such differences are very obvious.

I'm now thinking of replacing the Tektros with Shimano R650 because I have read that they're Ultegra quality and way better in performance. Also worth mentioning is that the Tektros are looking shabby after only one winter, rusty pivot bolts, springs etc, and I suspect are deteriorating quicker in terms of pivot wear and therefore braking performance.

Shimano R650s are awesome. I have one on the front of my bike and it's almost as good as the Ultegra brakes on my dad's bike. Great stopping power and modulation and they look awesome!

MattC59

I've got Ultegra brakes on my road bikes and have never had an issue with braking. I can easily look the back wheel if I feel and am sure that I could stand the bike on its nose if I rally wanted to.

Brakes may outwardly look very similar, but there are huge differences between rands and models.

CiB

I run Ultegra and can lock the back wheel on demand and get close to the tipping point over the bars if I fancy it (or if I don't). Beyond a point there's no benefit in having better brakes - the geometry and weight balance of the bike makes it pointless.

If your brakes aren't as good as you'd like, try washing the rims & pads with warm v dilute soapy water. Clean rims with a fine residue of soap are v good at stopping.

Neil_aky

Thanks for the great answers - especially BordersRoadie - these are the answers I was after; I'm an engineer so was struggling with being told by people that 'x' brakes are better without any good reasons. I'll change the pads first to some of those recommended KoolStop Salmons get recommended by everyone and then I'll look at callipers.

One last question, the B-Twin pads are replaceable - is this a standard size?

I can't believe how much has changed in cycling in 20 years (the last time I owned a road bike (racer) was about 20 years ago).

paul_mck

cheap calipers will flex more than more expensive ones despite being the same rough shape. pull your brakes on tight then pull a little more and youll see the caliper flex. So part of your pull energy is being wasted flexing the caliper instead of gripping the wheel.

braking surface also a big factor (I think someone mentioned that above too).

t4tomo

marcusjb wrote:

^^ definitely

Any decent caliper brake with decent pads, newish cables, that have been set-up properly will be able to lock either wheel up way before the tyre gives up (on a dry clean road).

but thats an argument for my point not against it

one you've locked the wheel up, its the amount of tyre in contact with the road that slows you down (friction and all that) and on a road bike thats not a lot.

paul_mck

problem generally isnt dry weather though its in the wet when the different bits of gear really start to fail monumentally (down a hill in the wet, brake at the bottom, no brakes!). We have all been there.