A new dawn (DIY brake mount and CARBON CATACLYSM content)

Andyl wrote:

1. They should be on the same side front and rear. Can’t go on the drive side on the rear so must go on the non-drive side.

Umm. Pardon my French. But beau locks. 😉

Or that bike designers actually know much when it comes to engineering.

Exactly.

we have discs on one side for two reasons.

1 it can only go on one side on the back

2 you’d have to manufacture two different calipers to have them on different sides unless you put the front one in front of the fork which looks crap.

so basically manufacturing / marketing

Ooh fair point re reciprocity. Seems irrelevant here though.

Utterly. I like clubbers version too..

Putting aside the question of attaching the mount, is there not a potential problem in using a conventional fork blade for disc braking? I thought that disc fork blades are usually beefed up at the lower end to handle the different braking forces?

haha. you’re not right al!

you want teh video?

YOU CANT HANDLE TEH VIDEO!

give it to 3:50pm, FFWD to 26s in:

We see the fear in your eyes in that final scene.

Surprised it at all didn’t fall to bits when you rode off the kerb

That was a nice first test, but now you have your confidence I really think you should be going a bit faster and braking a bit harder.

For some reason Al I imagined you to be a fair bit older.

dissapointed^^^^^ won’t be happy till you at least arrive in frame from stage right doing a proper endo stoppie on your front wheel from about 35mph. Bonus points will of course be awarded if you arrive in shot already sliding along on your face………… 😉

As chief said, plus riding straight towards that hairdressers car

endo!

It would probably be good if you could also ring that bell at least once during the test.

cynic-al – Member
What do you think Martin?

The way I see it, the caliper pulls away from the mount when the brake is applied. Tension both top and bottom. Whenever I have had a cable operated brake wound up and gripping the disc, it rotates with the wheel and pulls away from the bracket top and bottom.

I’m still fighting to see where folk find it under compression at the bottom fixing.

Your turn, what do you think? :OD

I_ache I never know whether to take that as a compliment or not – I usually choose to 😎

New pads weren’t biting so top braking was unachievable.

Martin, looking at boblo’s pic, I think the bulk of the braking force will be taken by the carbon wrap around the IS adaptor mount’s top sideways hole and there won’t be much other stress. If you take his blue arrow backwards it goes through that hole.

I think the bulk of the braking force will be taken by the carbon wrap around the IS adaptor mount’s top sideways hole and there won’t be much other stress

Yeah, I agree.

I still can’t picture any compression at the lower end,though. Even if the forces were in the direction of the blue line* it shows the caliper pulling off the bracket. No compression.

*the blue line and its imaginary force is wrong too, Isn’t it? Maybe I’m wrong but would it not follow the curvature of the disc? Would it not be a shearing force?

So, did you break a sweat trying it out? It would have been clip of the decade if it popped off :OD

I don’t like the colour.

Blue line is correct.

No sweat, haven’t you seen my similar threads before?

For some reason Al I imagined you to be a fair bit older.

and less beardy.

It’s like seeing an Archers actor. They never quite match the mental image you have 😉

AL you are awzums,gotta love a trier .
Please be updating youtube with an endo 360 combo 🙂

So the mount is still on? Keep testing, I want to see a result one way or another.

And going back to previous comments on same side etc, sorry was drunk, didn’t explain myself very well. What I meant was back when it was decided which side was normal they obviously made some decisions. Some based on aesthetics, some practicalities, some engineering, some production/cost etc. The engineering challenge is by no means so great that allowances for other reasons can’t be made.

By sticking to the same side you end up with a system that looks more balanced (even if it isn’t) but also means you can interchange bits easier while keeping the caliper behind the fork leg and out of harms way. A good example here is Als CL brake disc which is technically turning the wrong way in use but I doubt it will matter in this case. In a world where people line up tyre logos with inner tube valves I can’t see brakes being on opposite sides going down too well!

I remember Cy explaining the road rat brake position, I can’t remember why but it did make sense. Was possibly due to adapting an old fork design (like Al) and/or as it means the wheel is less likely to be ejected from the drop outs and it’s primarily a commuter bike so less rocks etc to smack a front mounted brake caliper.

But yes in other things when you don’t make things symmetrical, or at least consider the effects of not being symmetrical, you can get problems (eg vibrations, undesirable loadings you now have to allow for etc etc).

less beardy

I dunno, anyone attempting bodging of this magnitude was always going to have a beard, weren’t they?

I thought the roadrat things was also about making ‘guard mounting easy?

You may be right IA – it’s just not the mental image I had of him.

TJ always had wild grey hair and raggedy beard so Al, as the antithesis of TJ was clean shaven and smart. Odd, isn’t it.

I salute you Al!

I still can’t picture any compression at the lower end,though. Even if the forces were in the direction of the blue line* it shows the caliper pulling off the bracket. No compression.

The pivot point, surely.
As a rotating force it won’t be even across the block….

Correct.