Mechanics and Fixing Any Questions Answered

thanks. Was thinking that plus one of these

Got a SP PD8X dynohub, feels to me that the bearings are binding a bit.. turns alright-ish in the hand (for a dynamo) but if I clamp it tight in the truing stand it feels very stiff to turn.

Was wondering if anyones ever experienced it before with this hub? Or if they think it could sort itself out with use… don’t really wanna un-assemble it if I can avoid it.

Perfectly normal. Most of the time you need to crank up the truing stand tight or they will start jumping out when trying to spin it.

It doesn’t feel normal, is what I’m trying to say.. Built up maybe 10+ of these. First time it feels bindy like this, and v noticeable when stand is tight.

I’m speculating but feels like the bearings aren’t properly seated or are slightly out of alignment with each other

Interesting, I would call the importers.

What is the black valve and why won’t it inflate?

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looks like a valve extension you screw on th existing valve (for deep rims). maybe the real valve core underneath it is still closed?

It doesn't look like an extension from here. I reckon you've simply lost that valve core. Which might mean it's a dead tub unless the core is replaceable.

You might be able to find an expanding bung that would fit into the wishbone that you could bolt the mudguard up to (by drilling a hole through it). Some MTB front mudguards work on the same principle.

I did this on my sons bike (the hole was already made by last owner) and used a bar end plug as the expanding wedge. Works a treat!

The wishbone is capped off I'm afraid. Think I'll go down @PhilDAS route

How essential are the serrated washers that come with brake calipers? What function are they meant to serve between the caliper and the frame?

It’s to stop them from slackening off. Ideally they should be there. Alternatively you can use a nyloc nut but most modern bikes have recessed nuts, therefore this wouldn’t be possible.

It’s not 100% essential, your brakes will still work but it’s best practice to have it. And when it comes to brakes it’s best to have them working and set up correctly. Or go brakeless ftw.

The wishbone is capped off I'm afraid.

Drill it and riv nut it?

I assumed that they (like the image attached) went between the caliper and the frame. I can't see how that would stop them from slackening off.

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Think they’re supposed to stop twisting, not slacking off (the thick ones also act like a bit of a standoff spacer too)

the thick ones also act like a bit of a standoff spacer too

That's the only time I've ever bothered with them, to space the caliper out for clearance usually around the headset cup.

Oh right I was thinking of the type you get on old racers. They look like fans and a bit springy

That makes more sense, although I can't say that I've ever had a problem with them twisting. The main issue I have is lining them up vertical in the first place, I can never work out how you can tell if a caliper is nominally vertical given that they also have a centering screw that can adjust the pads left or right.

The main issue I have is lining them up vertical in the first place,

Like, so the pads are evenly spaced?

The black valve could also be on the wrong way around. Remove it from the tubular, remove the valve core below ( if there is one) and insert the other end. Then screw the valve core into the larger diameter end of the extender.

Perhaps, I’ll probably just return it to the eBay seller though. No flats on the valve core so any removal would likely mar the threads.

Pinnacle Arkose cable routing question.

How do I use this “opening” on the LHS of the down tube? It has a tiny plate that screws into place with just a plain hole in it. I think it should be for the rear derailleur but cannot see how to use it. There is no cable stop in a suitable place, and the cable guide under the BB shell looks like it is for just the cable with no housing.

Is there a part missing? And if so wtf did they do it like that and not just put an angled opening suitable for a cable stop like they did on the RH side of the down tube?

Thanks!

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The one that's just a hole is for Di2 or dynamo wiring usually. You need one of the bolt in inserts with the angled cable stop

Is that also a Vittoria? If so, thats just an extender that goes UNDER the red Vittoria extender that has the valve core in it. Its a different, finer thread on the Vittorias, as you can see on your picture between the end of the red and the black extenders.

Neither the tub itself, or the black extender has a valve core in it. If you're thinking of returning it, what tub was it, and how much did you pay for it? might be interested.

Marked in red is where your black piece goes:

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