Yet Another Cycling Forum
General Category => The Knowledge => Topic started by: bludger on 10 February, 2019, 08:58:27 pm
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I've got my eye on a used bike with a solid non-drilled fork. I love the look of the bike but a ride without a front brake is no bueno.
Someone told me earlier there is a brake system in which a caliper is mounted on a bracket which is held in place between the head tube and the steerer tube/fork, could anyone do me a favour and drop me a hint on how to look into this? Googled as hard as I can, no luck.
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https://www.hubjub.co.uk/dia-compe-brs101-clamp-on-track-brake-front-1321-p.asp
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Blimey that seems like a steep bit of dough for some extra metal clips but that's the market I guess. Thanks!
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Yeah, it's not a cheap solution. The rear brakes are half the cost!
Might be cheaper to replace the fork, or have it drilled/braze-ons added.
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To be honest the cheapest solution is to stop spending cash on bike stuff like a mug that I am 😂
This is the bike I was eyeing up https://www.lfgss.com/conversations/330423/ it's gorgeous and £200 is criminally cheap
(https://lfgss.microco.sm/api/v1/files/249605666e4a009dad979d2ea79572b9b5232716.JPG)
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Ah, it'd be a crime to drill that fork.
But it's a bargain even with the eye-watering price of the brakes!
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It's gonna be 'uncomfortable' on normal roads.
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Most undrilled steel track forks have round fork blades that flex excessively when a front brake is fitted and I'm not thrilled by the resultant fatigue effects. I'd fit a different fork for road use and swap it back as needed for the velodrome.
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It's gonna be 'uncomfortable' on normal roads.
Yes. Hopefully he’s got rock hard thighs to counter the lack of a saddle.
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Erm, forgive me here but that is a track bike. It's designed to be ridden round a track in circles along with other bikes without brakes (for safety reasons).
It's not a road bike, pretty or not it was never designed to do what you want to do with it, which is ride it on the road. As mentioned above the forks are not designed to have the loads imparted by braking go through them and have you checked the wheel rims even have braking surfaces on them?
If you think it's pretty then buy it but mount it on the wall and look at it or take up track riding - I understand it's quite good fun. I wouldn't try to adapt something for the road without thorough research and a decent understanding of it's capabilities. There are lots of pretty road bikes around that are suitable and safe. Personally I'd ride one of those but that's just me.
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Erm, forgive me here but that is a track bike. It's designed to be ridden round a track in circles along with other bikes without brakes (for safety reasons).
It's not a road bike, pretty or not it was never designed to do what you want to do with it, which is ride it on the road. As mentioned above the forks are not designed to have the loads imparted by braking go through them
Is this another modern phobia? Turn the clock back only a few decades and many club folk had what were called road/track bikes i.e frame with track ends and no brazed fittings (so it could be used on the track) but with mudguard clearance so it could be used as a general purpose machine. I've had many like that in the last 50 years, all with round blades just as my current 653 frame has. Round fork blades do flex a little under braking, heavy braking that is, but on a frame with good clearance to the down tube it is not a problem. Even with oval blades, in the days of fag paper clearances care had to be taken to make sure the headset was tight enough to stop the tyre contacting the downtube - you can see what I mean on pictures of 1970s time trial bikes. Apart from tight clearances, the only place I know round fork blades have proved problematic, by breaking (correct spelling), is on the front of tricycles where two brakes are fitted to the front wheel. Even then, it takes some mighty fierce braking to cause a problem. Drilling the fork crown - I've done that a couple of times when I had a purpose built track frame that I wanted on the road for time trial purposes. I would have no problem at all riding the pictured frame, except that since it does not take mudguards it is pretty well useless to me these days.
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Having a track bike which can also have a brake system put on it so it can be legally rode to the velodrome is fun. Plenty of people ride track bikes with brakes on them without drama, I've seen more than a few on brevets including ones with pretty stingy lumps.
In any case I've decided to stick with the bikes I have. For now.....
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Not a modern phobia, I simply wouldn't do it. Equipment used in a particular way because others do is not something that stands in a court room if you are found liable in an accident or worse if you are killed. This last statement is based on recent news stories where such mods have been done and although not responsible for the accident were used as something to pin blame.
I'm sorry but it's the modern world. I've got an engineering degree and have worked in a bespoke manufacturing environment since the mid 2000s. The world has changed. I regularly see our customers attempting to modify our old kit for something it wasn't designed to do rather than come back to us in the first place - probably because they don't want to pay for our consultancy or experience. They usually end up paying twice in my experience.
If you want to modify that bike then do so. I'm not going to do it or ride it. I'm just saying make sure you have done your homework and make sure you know it is safe for you and you can document it is safe for the road.
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It's a 531 steel bike, not the space shuttle!
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It's still a modification on an item being used as some would view in a high risk environment but I'm shutting up now.
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Drum brake?
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I don't think you want a front brake on a fork with round blades *and* a front tyre that close to the downtube. If the front tyre ever touches the downtube, it will pitch you over the bars before you can say "ah bugger" and quite possibly bend the fork beyond repair. The rapid deceleration caused by braking *and* tyre-tube contact bends the fork more, it grabs harder, this bends the fork more, it grabs even harder...
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FWIW BITD I had a Holdsworth road/path frame built with a track tubeset (including the round fork blades) and used it as a fixed gear training/occasional hillclimb bike. I think it was about 74 degrees parallel. I didn't notice the fork blades flexing unduly, but then they weren't super-light and probably they weren't unduly challenged by the weinmann 500 calipers either.
Other bikes I used with fixed gear and brakes have had forks (some of which I have had to drill for a brake) with 'continental oval' sections to them and some of those were flexier than the round track forks were, presumably because they were built lighter.
I don't think you need to worry about the bike being unrideable (most of it is quirks that you will get used to), or the forks flexing too much with a caliper brake. The dia compe kit is expensive but it isn't very difficult to make something that will do the same job; just make a caliper mount by jigsawing a horseshoe shape from a piece of 3/16" aluminium sheet, and use strong band clamps to attach it to the forks. The trick is to make absolutely sure of two things
a) that the band clamps are at the exact same height as the brake blocks (this way there won't be any twisting of the assembly and the lack of a top mount won't be a problem) and
b) that there is no way on this earth that the bands will ever slide on fork blades
You can mount the brake behind the fork if you like; depending on how the bands are arranged this can give them an easier time. However you can end up with the caliper clouting the down tube too easily.
FWIW a hub brake could work but it really depends how the frame is built; there is a big difference between a sprinter's frame and a pursuiter's frame. Hub brakes work OK with nearly all road forks but they do put extra load into them vs a rim brake.
cheers