Spot the missing bolt!

[Bracechenko]

Wheeled the bike out this morning to ride to work and noticed this....

Details

Have you found the missing bolt yet? God knows how long it's been that way though!

[kebab19]

Sure the standard rear caliper is duff, you press the pedal down and nothing happens anyway :-D
Still, at least the caliper is still there

Loathe as I am to wash the bike more than twice a year, it's usually a very good way of spotting missing bolts etc.

[Bracechenko]

See i've always found that the rear bites really well for me. It'll lock if I give it any good pressure and is as powerful as i'd ever need a rear brake?

So, what is that arm for anyway that connects the caliper to the swingarm? Is it a torsion bar or something to prevent the caliper moving whilst braking?

[kebab19]

The standard rear caliper works fine for you? Wow....there is someone out there then :-D

It is indeed, and it stops the caliper trying to rotate around with the disc when you stomp on the pedal. I'm not sure if the bar setup or attaching the caliper to the swingarm is the better solution. I assume the bar setup adds to unsprung weight but having it & the rear caliper underslung lowers where the weight is, so cancels it out a bit.

[virtual bodysnatcher]

As far as I can see it's to stop the caliper rotating, my Spondon that had (probably still has tho' sadly not mine now) a single side swingarm had a torque arm run through the arm and via a few bars/rose joint connections to the frame so's braking forces were run into the frame or maybe just 'cos it looked exceptionally trick!! So not through the suspension at all, I think the rear is compressed as the brake pulls the swingarm "up", tho' could be wrong.... opposite of when you accelerate which contrary to what it feels like the back end's lifted as the chain top-run's pulling at the swingarm and in general the swingarm pivots above the wheel spindle centre which is why some racers put some rear brake on coming out of turns probably. I should imagine tho' that the closer to the swingarm pivot point the brake torque is fed the less it'll effect suspension?


Anyhows where do I send the circled answer and is there a no publicity box to tick?

[Major Rant]

I had one of those disappear on me once on a BSA with a rear drum and a pull-rod. It had the effect that as the drum rotated the rear brake locked full-on and threw me off the bike  .
 
At least with a rear disc it would simply rip off the hose and piss brake-fluid everywhere - brake would simply stop working.
 
(Not that it works very well in the first place, so you'd probably never notice  )

[richfzs]

See i've always found that the rear bites really well for me. It'll lock if I give it any good pressure and is as powerful as i'd ever need a rear brake?

Thats a relief, thought it was just me found the back strong enough

So, what is that arm for anyway that connects the caliper to the swingarm? Is it a torsion bar or something to prevent the caliper moving whilst braking?

Indeed it is...

[Skippernick]

I agree my back brake is plenty strong in fact i ended up 'backing it in' when filtering past stationary traffic inbetween two cars, well i locked the back wheel up anyway.
It was a total fluke.
anyway didn't fall off and pretended that was what was ment to happen.
Nick

[Bracechenko]

I agree my back brake is plenty strong in fact i ended up 'backing it in' when filtering past stationary traffic inbetween two cars, well i locked the back wheel up anyway.
It was a total fluke.
anyway didn't fall off and pretended that was what was ment to happen.
Nick

Hehehe....yep, been there and did that coming down a steep lane and a car come flying up it....slid the back in holding the weight on the front brake.....COMPLETE fluke and all done with composure, anyone watching would have been impressed but they didn't know that my sphincter could have crushed a golf ball as it happened!! 

Just tried to get the thread out and it's stuck like a reet bastard! Will have to have a better go when i've got time

[Bracechenko]

Does anyone know if the caliper is threaded where that bolt goes through? In other words, now that the nut has sheared off, should I be able to wallop the bolt thread straight out or does it need to unscrew out of the caliper?

Cheers
Brace

[born to be mild]

Ive just had mine to bits to paint it,its just a nut and bolt, give it a whack from the outside, the caliper isnt threaded and it will pop out. what i cant get my head around is how the bolt head sheared off, is the nut still there on the other side?

[Bracechenko]

Ive just had mine to bits to paint it,its just a nut and bolt, give it a whack from the outside, the caliper isnt threaded and it will pop out. what i cant get my head around is how the bolt head sheared off, is the nut still there on the other side?

Cheers mate, didn't want to start whacking it without knowing whether it was threaded or not!

I'm a bit puzzled too how it's happened but yes, the nut is still there on the other side. You can see that's it's rusty and I guess that constant stressing and un-stressing has finally caused severe metal fatigue. That bolt would constantly pivot with the suspension going up and down so I can see it wearing...wouldn't expect it to shear of course though!