Mechanics Quick Question Thread [Ask Questions Here]

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Mechanics Quick Question Thread [Ask Questions Here]
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Posted: Jan 22, 2020 at 16:51 Quote
Is there any consensus on whether swapping a 142 hub to 148 Boost is enough of a change to require replacing the spokes too? Hoping not, just weighing my option between rigging a spacer kit or going with the proper hub. TIA.

Posted: Jan 22, 2020 at 16:59 Quote
After rebuilding and servicing my Rockshox Deluxe RT, I noticed the shock would not use full travel. The shock "bottomed out" at 60 mm instead of the full 65 mm of stroke. This is the first time it had happened before. I also removed the air and compressed the shock, and like before, the shock stopped at around 60 mm and I could not physically push any more. Does anyone know the problem?

Posted: Jan 22, 2020 at 17:35 Quote
TheUnknownMTBR wrote:
Is there any consensus on whether swapping a 142 hub to 148 Boost is enough of a change to require replacing the spokes too? Hoping not, just weighing my option between rigging a spacer kit or going with the proper hub. TIA.

Even if I was using the same hub for the swap, regardless of spacing, I would never reuse old spokes.

Posted: Jan 22, 2020 at 17:50 Quote
THE-GUNT wrote:
Me shock will not extent past this position. What may be the issue?
I talked with Cane Creek and just for shits and giggles they are sending me a DB coil CS to replace the air .

Posted: Jan 22, 2020 at 18:05 Quote
seraph wrote:
TheUnknownMTBR wrote:
Is there any consensus on whether swapping a 142 hub to 148 Boost is enough of a change to require replacing the spokes too? Hoping not, just weighing my option between rigging a spacer kit or going with the proper hub. TIA.

Even if I was using the same hub for the swap, regardless of spacing, I would never reuse old spokes.

The reason I’m asking is because they’re not old. They’re high quality that don’t have much time or abuse on them thanks to some health issue that had me sidelined for almost two years.

Posted: Jan 22, 2020 at 20:33 Quote
TheUnknownMTBR wrote:
seraph wrote:
TheUnknownMTBR wrote:
Is there any consensus on whether swapping a 142 hub to 148 Boost is enough of a change to require replacing the spokes too? Hoping not, just weighing my option between rigging a spacer kit or going with the proper hub. TIA.

Even if I was using the same hub for the swap, regardless of spacing, I would never reuse old spokes.

The reason I’m asking is because they’re not old. They’re high quality that don’t have much time or abuse on them thanks to some health issue that had me sidelined for almost two years.

1. Get all the wheelbuilding specs for both hubs and the rims.
2. Run both scenarios through a spoke calculator.
-- If the new wheel requires longer spokes by more than 2 mm, it almost certainly won't work.
-- If the lengths are about the same, maybe you're in business.
3. Look at your current wheels. Observe how far the spokes extend into the nipples. The spokes should be flush with the end (outermost point) of the threaded portion of the nipples (i.e. you can ignore the slot where a screwdriver could fit).
-- If the spokes extend past this point, that's how much extra spoke you have.
-- If the spokes are flush or below the end of the nipple, you have no spoke length to spare.

Posted: Jan 22, 2020 at 20:57 Quote
I get all that. If I had built the wheels and had a record of the lengths I wouldn’t need to be trying to ask the question to people who might have enough experience to answer it. Which I can likely guess close enough without pulling one too. Sorry if that seems like a smart-alec response because that’s not my intent. I suppose I’m just trying to let people know why I’m asking the question and why they should consider only answering it if they have enough direct experience to know.

Then again maybe nobody either knows or they just throw new spokes on because my situation is rare. I looked at the hubs and the flange/spoke attachment hole diameter is slightly larger on the 148 Boost hub. I’m not sure if that’s intentional to allow a similar length despite the wider flange spacing or not? Had intended to ask the hub supplier today and it slipped my mind. They also take several days to respond. So thought I’d ask here because at least a few people in this thread have been doing this as a living for a long time and might possibly have some insight beyond just the standard way of figuring it out.

Posted: Jan 22, 2020 at 21:13 Quote
There is no universal answer. There is absolutely nothing we can do for you. The answer depends on factors included in the solution I provided for you. Even if the hub is the same make and model, you should still verify the manufacturer didn't change anything other than flange offset.

Here's another idea: if you know the hubs are exactly the same in every dimension other than flange offset, just enter some realistic, but fabricated, numbers for flange diameter, offset, ERD, etc. and run it through the calculator yourself. Then repeat with 3 mm more offset per side. Observe the difference in spoke length and the answer to your question will be clear.

Not a fan of your comment "why they should consider only answering it if they have enough direct experience to know". I have enough experience to know how much of a difference is made by 3 mm of flange offset per side, if that's the only difference, and I have enough experience to know I shouldn't just say "yes" or "no" without prompting the recipient to verify a few other things.

Posted: Jan 23, 2020 at 0:06 Quote
TheUnknownMTBR wrote:
Is there any consensus on whether swapping a 142 hub to 148 Boost is enough of a change to require replacing the spokes too? Hoping not, just weighing my option between rigging a spacer kit or going with the proper hub. TIA.

You could measure your current hubs flame shaving and diameter, plot it into your favorite spoke length calculator and do it again with the new hub and see where you sit.

Posted: Jan 23, 2020 at 2:05 Quote
ZoneCheck wrote:
After rebuilding and servicing my Rockshox Deluxe RT, I noticed the shock would not use full travel. The shock "bottomed out" at 60 mm instead of the full 65 mm of stroke. This is the first time it had happened before. I also removed the air and compressed the shock, and like before, the shock stopped at around 60 mm and I could not physically push any more. Does anyone know the problem?

Did you do a damper rebuild?
Could be the IFP height has come up during the bleed process and the damper piston assembly is hard stopping against the IFP

Posted: Jan 23, 2020 at 9:18 Quote
Should I clean my old rotors before bedding in new brakes? Same brakes / pads and the rotors were not contaminated. Can I just bed them in on top of the pad material already on the rotor?

Posted: Jan 23, 2020 at 10:27 Quote
I am building a dirt jumper and I recently found a 2017 fox 36 factory but it’s a 27.5 fork. Could this be lowered to 80mm or does it not go that low? I’ve seen this done with marzocchi bomber Z1’s?
Any help would be appreciated
Thanks

Posted: Jan 23, 2020 at 10:45 Quote
nojzilla wrote:
NO
No to the first question or no to the second question?
Thank you.

Posted: Jan 23, 2020 at 11:13 Quote
scjeremy wrote:
nojzilla wrote:
NO
No to the first question or no to the second question?
Thank you.

Yes


 
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