Mechanics and Fixing Any Questions Answered

Get a sick bash guard.

When buying bearings it's best to go for ones with a decent ABEC (quality) rating, go for 5 or better. Any eBay stuff without a rating will be just plain nasty !

Meh, abec ratings make sense for stuff that goes really fast or you need mega tight tolerances on, but anything with a proper seal from a reasonable brand in the right size will be fine.

Got some from wychbearings who I’d forgotten that I’d previously bought from. Cheers for advice folks

Wych are always great and super fast postage.

I'm setting this mech up with a 32 front ring
Says it can handle 36t at the back. Could I push this to 40 without to much fuss (without a hanger extender)?
https://bike.shimano.com/en-EU/product/c­omponent/deorext-m780/RD-M786-SGS.html

@Alban set this all up yesterday and can report it's all working fine. My bike has horizontal dropouts which allowed me to play with the position of the cassette.

Trying out some 650b wheels on my Bowman Pilgrims Disc frame. Clearances are quite tight but measuring the gap between the rear stays I should be able to get a 40mm tyre in there. Bought some Conti Terra Trails which have come up a bit big at about 41mm but when I drop the wheel in the tyre is touching the stays but only on the drive side. There should be enough room for clearance but I can't work out why the wheel is not centred properly. Could I use a spacer to compensate or does the wheel need re-dishing?

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With the bike standing on the floor, open and then close the rear QR to check that the axle is fully seated into both dropouts.

Now if your rim is still sitting off centre then either
a) something is wrong with your frame, or
b) you must re-dish the wheel.

You can test the frame by grabbing a different, healthy wheel (if you have one) and seeing if that sits straight in the frame.

I'm really quite meh about HT2 because of the lack of flexibility regarding chain line and q-factor. I like that square taper cranks can be set up as far inboard as possible on 1x systems by just dropping a afew £ on a new BB. With HT2 tinkering is basically impossible.

Square taper does take some stress out of it. Had this issue recently setting up an old SLX triple 1x.

The wheel has Thru axles so definitely seated properly and my 700c wheels are perfectly aligned so sounds like the 650 wheel needs re-dishing.

Are you using road or mtb ht2? With the mtb ones you have at least one spacer to play with and it can definitely help.

If you have a 68mm shell then there should be two driveside spacers that I’ve found can all go on the nds if needed. Probably not ideal but…

One other thing to check is that the tyre is seated perfectly evenly on the rim.

Although to be brutally honest, I don't think you've got satisfactory clearance even if you can get the wheel to sit evenly, especially for use off road. There will be absolutely zero clearance for any mud/dirt and the occasional branch/twig. Why not drop down tyre size to a 35 or 38mm CX size? c.35mm is honestly plenty big enough for general offroad use.

Yes, you might well be right. I have actually got CX tyres that I've used before on the 700c wheels which worked well but I wanted to have a separate set of wheels to switch to rather than the faff of changing tyres. So I thought I'd try 650b and go a bit bigger with the tyre.
I've got some slightly smaller 650b tyres on the way and will take these tyres off and check how the rim is aligned.

what ones make most sense to buy in terms of quality and finish?

NSK, SKF, NTN and FAG.

Are you using road or mtb ht2?

I'm not using either, in fact I've specifically passed up on some HT2 cranks (in favour of square taper) for kids bikes where I want to make the q-factor as narrow as possible. TBH, I've never worked out how the HT2 BB and crank combinations are meant to work with regard to 68mm vs 73mm BB shells. From what I can work out (happy to be corrected), they use the same width BB, but just use fewer spacers if you have a 73mm shell, so there's no reduction in q-factor as a result of having a narrower (68mm) BB shell, which seems nuts.

Only if you're thirsty for the Q. Otherwise it just means they work on more bikes.

Exactly yeah, 68mm shell = 2 drive side 1 nds, 73mm shell = 1 driveside. Re move 1 driveside spacer off using a bb mounted front mech or chain guide.

I bought some off brand bh59 hydro cable, and it came with its own olives and inserts. They look a little different to the shimano ones, my q is should I use the ones they’ve given me, or the shim ones with shimano levers and callipers? Or does it not matter :)

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I picked up some new 11 speed wheels for my 7 speed. Right now its cassette is on some wheels from a 9 speed donor bike, so I believe it should have a 4.5 mm spacer on the freehub at the moment. To go from 9 to 11 how much extra spacing do I need? Sheldon Brown seems to suggest 0.85 mm but I've seen 1.85 mm elsewhere. My new wheels did come with a 1.85 mm spacer so it would be helpful if it were the latter. (don't have a cassette tool to hand to try it yet)

@ffm @psg1ben I've come to the conclusion I'm going to run square taper on everything from now on for this reason.

Yep. 1.85mm 11 speed to 9 speed spacing.

Where should I take tubular wheels to be glued? Preferably east, central is OK.

If I detach a brake hose from Tektro Auriga hydraulic brakes and reattach it do I have to replace the barb and olive or can I get away with re-using the same ones?

Thanks

Probably alright to use the same ones. Double check the seal on the barb has survived. If it's an old/well used brake then replace both.