Cycling UK Forum

Oval crank tech wrote: ↑15 Apr 2024, 5:58pm OK now I am stuck, the 8 speed freewheel is so spaced it does not line up with the front chainline, is there a way make it work?

eh? A photo would help enormously, if you can manage it.

colin54 wrote:......weirdly two of the holes for the screws have a square hole (to resist turning) in the saddle top and two circular - the middle pair.......

I have never had one of these in bits but I would say that very probably all the holes were square until the thing inside them was turned many times and/or got hot. I'd have been tempted to hold the Al parts with a peg spanner, having first drilled two small holes in them.

Revolution wrote: ↑12 Sep 2022, 3:34pm I have a Brooks C17 Cambium saddle which after 5 years of light use has started to split along the underside of the front.......

I would probably attempt to repair that, by using a patch on the underside, trapped between the frame and the top. The front of the patch, being trapped, would see no 'peel' forces. The rear of the patch could be a lot larger, with a pointy edge, so there isn't an abrupt transition. The patch itself would need to contain a strong but flexible element. such as a woven nylon fabric. The body of the patch needs to be able to flex slightly, so maybe the best thing would be to first 'cast' the repair patch in situ, using a barrier layer (eg. cling film) to prevent adhesion. The patch itself could be made of multiple layers of woven nylon fabric, held together with PVA adhesive, a sort of synthetic leather if you like. Finally, the patch would be bonded in position using a different adhesive, eg. a contact adhesive.

It certainly won't hurt to file a nice radius onto the Al nosepiece, but alone, it is unlikely to be effective as a cure, because there is a stress concentration here anyway; this is where 'proper' Brooks saddles sometimes split too.

drossall wrote: ↑14 Apr 2024, 11:53pm........ chain widths are a little more variable than I stated.....

Nonetheless, your advice re chainrings is probably correct. Any chainring meant for 3/32" (3,4,5,6s derailleur) chain will almost certainly be no more than 2.2mm wide, in which case 9s (and higher) chain will fit and run OK, but not in a derailleur setup with more than two chainrings (or one, if you are being really fussy).

ncutler wrote: ↑15 Apr 2024, 9:32am my boat has anodized aluminium spars with a collection of stainless steel fittings and none of 'em are even slightly rusty.

maybe I should have added a few caveats there, such as 'on a bike' (crumbs, anyone'd think this is a cycling forum) and 'anodised high strength aluminium alloy'. As another poster has already pointed out, they use different materials on boats. Needless to say, there are no barrier layers used in your discs. The braking surfaces are probably made from a 400 series stainless (if so, a magnet should stick) and wherever the brake pads don't touch, it might be painted or lacquered to help ward off corrosion. The rivets are probably made of a similarly corrosion-resistant material, but being bereft of any passivation or coating, they will be amongst the first things to look rusty.

lightweight, attractively priced, stiff; choose any two. That amount of flex is quite normal if you try and make an Al frame very lightweight.

Jezrant wrote: ↑15 Apr 2024, 10:34am........It’s quite possible for a new alu frame to flex that much and that easily (as seen in the video the OP posted)? Is that really normal? And how long would it then take to harden fully?

First I should say I don't remember seeing the video. Second, 'flex' is a term normally attributed to purely elastic deformations. No aging treatment can greatly alter the stiffness of a frame. only really the yield point, ie. when the deformations become plastic in nature. Normally frames age ~80-90% in a few weeks ie. in the boat from Taiwan, but this does depend on the ambient temperature.

would it not be just as easy (if not even easier) to make a spacer to be fitted to the spindle? I suspect that you can make something suitable out of an old spoke. btw if the bearing outers are a sliding fit in the cups (or the inners a sliding fit on the spindle come to that), it isn't a bad idea to use bearing fit compound or similar.

BerlinMatt wrote:..... I presume it's meant as a contrast to the painfully tasteful bikes he builds otherwise https://meerglas.org/blog/category/randonneur

I see what you mean; there's only one bike with mudflaps in the link above.

alexnharvey wrote: ↑8 Apr 2024, 8:45pm I'm a bit bewildered by the width of these huge rear flaps. What is the point?

obviously they have to be wide enough for pictures of dolphins?

I suggest gravel bike with dropped handlebars, set higher than you would have them on a road bike.

the oil in red rubber grease is usually some kind of vegetable oil. In brakes, it is best used beneath the dust boot. 'Copper greases' vary wildly in copper content, from ~1% to ~50% so they are very far from being all the same and should certainly not all be tarred with the same brush.

Cyclothesist wrote: ↑14 Apr 2024, 8:36am......OK you have me there Brucey, maybe a third as good?

I bought the 'reassuringly expensive' spurcycles bell as a gift for a friend and they were delighted. Another friend had their nearly identical bell pinched off their bike whilst it was parked. In the latter instance, the thieves made off with a copy which cost about £5, so presumably they were fooled, anyway..

I think there would be something wrong if you took a piece of stainless steel connected to a piece of anodised aluminium, spayed everything with salty water, left it a few weeks, and nothing showed any signs of corrosion.

without the spacer, the BB would need at least one lockring. The spacer normally allows you to fully tighten a lockringless LH cup, by accepting a high load in compression. You can use a length of tube as a substitute but it needs to be the exact correct length (as per the bearing spacing on the spindle) ideally plus a small allowance (no more than ~0.2mm or so) to allow for the elastic compression of the spacer when the LH cup is tightened.
btw a 6002 bearing is usually 15mm bore, 32mm OD, 9mm width.It isn't a bad idea to measure up carefully; I have heard of seals with 6002 writ upon them being found in bearings of a quite different size. I suggest that you also convert the bearings to DFC specification.