Cycling UK Forum

Hi,

Just a quick question.

I'm using a 10 speed cassette on an 11 speed freehub body with the little spacer behind the largest sprocket as is the norm.

I've gotten a spare wheel for my turbo trainer which has an 8, 9 & 10 speed compatible freehub body.

If I put an identical 10 speed cassette on my new wheel (obviously now without the little spacer) will I have to adjust my limit screws or will the cassette sit in the same position between the dropouts?


Cheers

Hi,

Recovering from an injury and have decided that I'd like to spin my legs with little to no resistance on my bike.

Is it possible to remove (or simply adjust) the "roller" part (the part that provides resistance) so that it isn't touching my tyre at all and just to use the gears on my bike for resistance adjustment?

As far as I can see the rear of the bike is lifted and suspended entirely with the clamp on the QR?

Will this create any additional stress on the frame/axle or is the support provided by the "roller" minimal or indeed non existent?

I'm not really up for investing much money initially and don't have a spare wheel/tyre/trainer tyre. Don't want to wear out my tubs for when I'm able to get back out.


This is the cheap, simple trainer I'm considering FWIW:

https://www.amazon.co.uk/Oypla-Indoor-B ... =1&sr=8-16



Cheers guys.

P.S I understand there may be many suggestions involving just finding a cheap spare wheel from somewhere. I understand I may have to do this, but I'm really looking for an answer to the above questions first ideally. Thank you.

http://smutpedaller.blogspot.com/2012/0 ... grade.html

There is something I've found which illustrates my point perfectly.


Scroll down to pictures 6 and 7.

Picture 6 shows the brake with the cable installed ready to go- plenty of clearance between the brake arch and mudguard.

Picture 7 shows the quick release open - no clearance at all between the brake arch and mudguard. This lack of clearance would be emphasised even more if the cable snapped.


FYI that isn't my blog, hopefully the author doesn't mind the free advertising!

Martin rereading your posts I think you might be visualising the situation incorrectly and for that I can only blame my description, of course!

To be clear we are discussing vertical brake clearance, so nothing related to pad clearance when removing a wheel etc.

See my edit on Brucey's image- when the cable is not installed (or snapped!!) the red area is the lowest (reducing vertical clearance) but when the cable is installed and I'm ready to KOM Mont Ventoux the red area is actually slightly above or inline with the blue area, increasing the vertical clearance. So the worry is when you experience brake cable failure, which I know is unlikely, the vertical clearance is reduced and the red area is now dragging on your tyre (or locking up your wheel, which is my perhaps unnesscessary worry).

Hey Martin, I can provide pictures at some point in the next day or two perhaps. But if you look at Brucey's useful picture and imagine squeezing the pads together, you can visualise how the "front arm" is lifted up and increases vertical clearance for a tyre.



FWIW I've noted the same thing on another set of short reach recessed nut Tektro dual pivots. This was at least a year ago so I can't remember the exact model. But I was swapping from some single pivot brakes and when I installed the new Tektro brakes the frame no longer cleared the 25mm tyre- until I squeezed the pads together (so that they sit in their natural couple of mm from the rim position) then there was an acceptable amount of vertical clearance.

At that point I decided I didn't want to risk it and harvested the corrosion free barrel adjuster and cable clamp for the old single pivots! Now I'm wondering if I was being a bit too cautious.



Maybe next time I'm changing my cables I can shoot a quick video spinning my 28mm tyre and cutting the old cable to show how the brake opens up fully, the "front arm" drops down and drags (or indeed halts?) the tyre.

MartinC wrote:I don't understand what's going on here. R559 are deep drop brakes with a extra wide quick release that opens for fat(tish) tyres. I've used them on LX17 (622x17) rims with 32mm tyres and with the QR open they drop out with room to spare. Prior to cabling they're open much wider like most DP and SP brakes, they even come with some black sticky tape to protect the right hand caliper from scratching when they're wide open. Without cabling they should open until the cable fastener hits other caliper arm.

Opening less wide with no cable attached makes no sense to me - what am I missing?

Sorry they're actually R359 which are mid reach in the Tektro range.

If you search for a pic of one you can see how when the calliper is fully opened one of the arms dips below the bottom of the "arch" of the calliper. This arm then gets squeezed in and the arm moves above the bottom of the arch creating more clearance.

I'm now thinking that in real life the only time I'm likely to suffer brake cable failure is under heavyish braking and I would be prepared for slowing down anyway. So perhaps this isn't such a massive worry really, especially if as Brucey says you're not likely to come to a dead halt if you're using slicker tyres.

I imagine you'd be even less likely to lock up the wheel in that situation if you were using mudguards (I'm guessing the tyre would slide round the inside of the mudguard (under the caliper) even easier than on the underside of the caliper.

Brucey wrote:

johnweightsen wrote:
So if the cable broke I imagine the top of the caliper would be enough to lock up the wheel. Or am I wrong..?

th arm rubbing on the tyre won't be a very effective brake. You can probably try it and see if you like, by starting with the cable slackish and then flicking the QR open

cheers

Good idea, I'll give that a test and see. I'm naturally quite cautious having worked in life insurance for a while!

Would the design of a single pivot caliper have the same characteristic (less clearance with the arms fully open)?

Brucey wrote:I think if the cable broke the arm might rub on the tyre but not slow you down that quickly.

cheers

Thanks for the response.


I'm not sure myself. With a 28mm tyre (and no cable installed) you can't actually get the wheel all the way into the front dropouts.

But of course with the cable installed it's no problem.

So if the cable broke I imagine the top of the caliper would be enough to lock up the wheel. Or am I wrong..?

Hello,


I'm using Tektro R559 brake calipers.

When my brakes are set up with the pads the appropriate distance from the rim I can clear a 28 and possibly 30mm tyre.

But when the brakes are initially installed without cabling (so the arms are fully open) I can just barely clear a 25mm tyre.

I'm right in saying that if I installed a 28mm tyre and experienced brake cable failure I would ironically be pulled to a halt very quickly (and dangerously) right?


Is this a common issue with all/most dual pivot calipers?

Can anyone recommend a nutted dual pivot caliper that doesn't have this "flaw"?

Would using single pivot calipers eliminate the "flaw"?



Hope someone can alleviate my curiosity.
Cheers.

https://www.sjscycles.co.uk/gear-spares ... oy-frames/

Problem solved, link is for anyone else in the same position.

Hi,

I've been using my Dura Ace 7900 downtube shifter on a bar end mount and would now like to move it back to the downtube.

Unfortunately I've misplaced the little piece that goes between the braze on and the indexing unit.

Example:

Downtube -> Braze on -> MISSING PIECE -> Indexing unit -> Lever you physically move (or miss entirely and shear your nails off on the front tyre).


Sorry if I've not named the parts correctly but hopefully someone will understand.



So does anyone know any online retailers that sell this small part? Hoping to not have to buy a whole new shifter set!



Cheers.

Hey, can I use the front shifter (bar end, downtime etc) if it is friction operated for my rear derailleur?

Is the answer- "yes, but you may not be able to move across your whole cassette"..?


Has anyone tried the front shifter from Dura Ace 7900 bar end to move across a 10 speed cassette?



Thanks.

I suppose this topic is just yet more proof that we're all a bit different.

Regardless, still interested to hear everyone's opinion and maybe even get an idea of how everyone else sets up their essential tools etc.

Has anyone tried a tool bottle with the lock wrapped round it?


And I'm sorry, but I promise I can notice the difference in handling!

nsew wrote:A top tube frame bag would position the weight better and provide better access. Personal favourite is the Ortlieb (4L). Strong zip, tough, light (170g) and waterproof. https://www.ortlieb.com/uk/frame-pack-toptube

I was using the 4.1L Ortlieb Saddle Bag, really well made products.