Mechanics and Fixing Any Questions Answered

Thanks

Thanks everyone

Does it need an article? It's just using a fork that's long enough to account for the length of the suspension fork the frame was designed around.

Fair enough. Given how many mistakes I make around mechanical stuff I wanted to make sure I knew what sort of rigid fork would be suitable before parting with any cash.

I've not tried this, but if it's assembled as far as frameset+wheels+post+saddle then you can get a friend to sit on the bike (and hold a rail) while you measure the forks?

A-C of the fork it was designed around minus ~25% of that forks travel and then buy any fork you like that says it's suspension corrected for your wheel size as they're mostly pretty similarly designed for short travel suspension fork swap outs as you don't get too many people whacking rigid forks on hardcore hardtails designed for 150mm travel, the calculation mentioned will mean you don't get something wildly wrong though.

Ain't nothin but a G - Sprang?

Would rep

Anyone know if, with ht2 cranks of the same model (let’s say Ultegra 6600), is the chainline for the outer most chainring position the same on double and triple cranks or does it change?

Also I feel like the triples are 130bcd for the two outer ring positions right?

Anyone know if, with ht2 cranks of the same model (let’s say Ultegra 6600), is the chainline for the outer most chainring position the same on double and triple cranks or does it change?

It changes. The big ring on the triple is further out.

Also I feel like the triples are 130bcd for the two outer ring positions right?

Yes.

Bah, that’s annoying but also kinda what I expected.

Cheers.

Crank states what size BB for correct chainline with 68mm shell.

Do I just add 5mm to that to fit to 73mm shell? (And order a '73mm BB')?

Thanks

Is it an axle length that it states? That shouldn't change for a larger shell but you might get interference issues depending what length it is.

If you go 5mm longer the chainrings will all be sitting 2.5mm further out than they should be.

Doh yep that makes sense, thank you @M_V

Here are some numbers for fc 6700 which confirm what Brommers said. They are from a shimano frame specification manual that I can't find at the moment.

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Fucks sake I've just threaded the disc mount on my rockshox. Is the fork toast?

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https://bermstyle.com/installing-a-helicoil-repairing-a-stripped-fork-post-mount/

@fredtc thanks

Anyone know of a machine shop or the like that would drill out and fit a threaded insert? On the north west side of London if possible, but anywhere really would do.

I'd rather get a proper insert than a helicoil, but drilling out with a hand drill isnt something I'm keen on (having done it before)

I'd rather get a proper insert than a helicoil

No better insert than a helicoil for that job.

Its a 1.5mm bolt going into a steel block. I'm not totally clear on the merits of helicoil vs threaded insert, but for the size and the cutting into steel i'd assumed an insert would be the way to go

That said, the question still stands - is there anyone that would do this kind of work in London, whether heli or insert? Seems like the 'one-man with a lathe' machine shops are all ancient history now!

Edit nvm!

Its a 1.5mm bolt going into a steel block.

Given the bolt size the torque you'd be doing it up to must be pretty low no?

Helicoil or a timesert all the way, you can bond them in with green loctite.
Front pm disc mounts the caliper mostly push up against the fork leg so bolts don't see big loads. Seen plenty of older forks with cracks in the casting caused by folk using bolts too long, and then they've just kept riding it!

A decent bike mechanic can take care of it. Machine shop prob overkill. Also most the min charge is £140 for even looking at something

I have a set of magura hs11 which I'm trying to fit to rear u brake bosses (I've seen it can be done). The clamps are positioned up side down, and they've been filled to within an inch of their life but the pads are still not low enough. If I can't get them to fit are there any other options? Are there any u brakes that have enough clearance for mudguards over a 26 * 2.1 tyre? This is pretty much the final piece of this project and it's doing my head in, so any ideas would be greatly appreciated

Frame material? Swap the bosses to regular canti/v brake?