Mechanics Quick Question Thread [Ask Questions Here]

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Mechanics Quick Question Thread [Ask Questions Here]
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Posted: Aug 9, 2022 at 13:08 Quote
BenLow2019 wrote:
MTBsnow wrote:
Swapping stems and the new one will likely have a slightly different stack height. Not sure exactly how different but within +/- 2 mm. Will I be able to use my current headset spacer setup and steerer tube length since its such a small difference or should I get new spacers?

Nobody can answer this without knowing the dimensions.
If the new stem is 2mm on the plus side and your cap bolt can still reach the star fangled nut then you'll probably be okay. If the new stem is 2mm on the minus side you may be okay unless the steerer protrudes beyond the top of the stem then you'll either have to add a spacer or shorten the steerer.

Bottom line: measure and determine now or wait and see when the stem is installed.

Good luck.

Got it. The new stem stack is 40 mm but idk what the old one is and it’s hard to get an accurate measurement without calipers. I’m getting about 39 mm but can’t be sure. It’s a Ride Alpha Freeride stem. No info on stack online…

Posted: Aug 9, 2022 at 13:39 Quote
MTBsnow wrote:
BenLow2019 wrote:
MTBsnow wrote:
Swapping stems and the new one will likely have a slightly different stack height. Not sure exactly how different but within +/- 2 mm. Will I be able to use my current headset spacer setup and steerer tube length since its such a small difference or should I get new spacers?

Nobody can answer this without knowing the dimensions.
If the new stem is 2mm on the plus side and your cap bolt can still reach the star fangled nut then you'll probably be okay. If the new stem is 2mm on the minus side you may be okay unless the steerer protrudes beyond the top of the stem then you'll either have to add a spacer or shorten the steerer.

Bottom line: measure and determine now or wait and see when the stem is installed.

Good luck.

Got it. The new stem stack is 40 mm but idk what the old one is and it’s hard to get an accurate measurement without calipers. I’m getting about 39 mm but can’t be sure. It’s a Ride Alpha Freeride stem. No info on stack online…

According to a listing I found here on pinkbike, the rise on your current stem is 39mm, at least for the 2020 models.

Posted: Aug 9, 2022 at 13:46 Quote
MTBsnow wrote:
Got it. The new stem stack is 40 mm but idk what the old one is and it’s hard to get an accurate measurement without calipers. I’m getting about 39 mm but can’t be sure. It’s a Ride Alpha Freeride stem. No info on stack online…

Right then, if I'm imagining this correctly, it sounds like your new stem is 1mm on the plus and therefore if your stem bolt will still reach the star fangled nut (and I'm willing to bet it will) then you are good to go without adding a spacer or shortening the steerer.

Posted: Aug 9, 2022 at 22:08 Quote
Twenty6ers4life wrote:
gabriel-mission9 wrote:
nubbs wrote:


Oh I know it! I'm just trying to be nice not publicly bash every eagle derailleur they currently produce. But you got me covered

Just as a random and completely unhelpful anecdote:
My sram mechs have never had any noticeable clutch tension whatsoever. Ever. Straight out of the factory, the clutch achieves nothing.
My shimano mechs have always had pretty good clutch tension. However you can switch the clutch on and off on shimano mechs, and i tend to leave them switched off. I spend quite a lot of time and money keeping my suspension moving as free as possible, so it seems entirely counter intuitive to then purposely attach a clutch to it.
All my bikes have at least a top guide and a n/w chainring. All my bikes that I hammer through rowdy terrain have a top and bottom guide and a hefty chainstay protector. No dropped chains. A perfectly acceptable amount of chainslap noise.
IMO, clutch mechs are essentially pointless.



I 100% agree with this. Clutches do nothing except mess up the suspension and add unnecessary weight.

Going single speed (DH) was THE biggest improvement I ever made to my suss

Posted: Aug 9, 2022 at 23:05 Quote
gabriel-mission9 wrote:
nubbs wrote:
Nobble wrote:
AXS clutches are mechanically no different to the standard ones. There’s just no housing to stabilize the B link.

Oh I know it! I'm just trying to be nice not publicly bash every eagle derailleur they currently produce. But you got me covered

Just as a random and completely unhelpful anecdote:
My sram mechs have never had any noticeable clutch tension whatsoever. Ever. Straight out of the factory, the clutch achieves nothing.
My shimano mechs have always had pretty good clutch tension. However you can switch the clutch on and off on shimano mechs, and i tend to leave them switched off. I spend quite a lot of time and money keeping my suspension moving as free as possible, so it seems entirely counter intuitive to then purposely attach a clutch to it.
All my bikes have at least a top guide and a n/w chainring. All my bikes that I hammer through rowdy terrain have a top and bottom guide and a hefty chainstay protector. No dropped chains. A perfectly acceptable amount of chainslap noise.
IMO, clutch mechs are essentially pointless.

Dude you are one gem of a mechanic

luckily to anyone who wants to check how clutches on rear mechs work can watch many videos on youtube testing with clutch engage/disengage from both brands, then you can make up your mind

Also chain can be f*cked up on the cassette as well, what's the point if you don't loose the chain from the chain ring but is crossed over between three cogs at the cassette or drop between the last cog and the frame drop out. Ask me how I know.

Posted: Aug 10, 2022 at 1:46 Quote
adespotoskyli wrote:
gabriel-mission9 wrote:
nubbs wrote:


Oh I know it! I'm just trying to be nice not publicly bash every eagle derailleur they currently produce. But you got me covered

Just as a random and completely unhelpful anecdote:
My sram mechs have never had any noticeable clutch tension whatsoever. Ever. Straight out of the factory, the clutch achieves nothing.
My shimano mechs have always had pretty good clutch tension. However you can switch the clutch on and off on shimano mechs, and i tend to leave them switched off. I spend quite a lot of time and money keeping my suspension moving as free as possible, so it seems entirely counter intuitive to then purposely attach a clutch to it.
All my bikes have at least a top guide and a n/w chainring. All my bikes that I hammer through rowdy terrain have a top and bottom guide and a hefty chainstay protector. No dropped chains. A perfectly acceptable amount of chainslap noise.
IMO, clutch mechs are essentially pointless.

Dude you are one gem of a mechanic

luckily to anyone who wants to check how clutches on rear mechs work can watch many videos on youtube testing with clutch engage/disengage from both brands, then you can make up your mind

Also chain can be f*cked up on the cassette as well, what's the point if you don't loose the chain from the chain ring but is crossed over between three cogs at the cassette or drop between the last cog and the frame drop out. Ask me how I know.

You can't disengage the clutch on sram mechs. Although this isn't really a problem, as they don't work anyway.

If your chain is dropping off either end of the cassette, then your mech is incorrectly adjusted. Any bike shop will be able to sort this out for you, but if you are inclined to have a go yourself, there are plenty of guides online that will talk you through it. It's a relatively simple job, and a good one to familiarise yourself with if you are just getting into maintaining your own bike.

If your chain is crossed over three cogs at the rear, this will sort itself out as soon as you start pedalling. If it happens regularly, then there is likely something wrong with the spring tension (or b tension adjustment) on your mech. Sram x-horizon mechs are designed in such a way as to pretty well eliminate ghost shifts, and shimano mechs tend to have beasty return springs which again essentially eliminate ghost shifting. So yeah, if it's happening a lot you probably want to investigate whats come out of adjustment.

Back pedalling during more boring bits of trail often leads to the chain dropping out of the lower gears and then crunching back into place when you start pedalling forwards again, so avoid that if possible.

Posted: Aug 10, 2022 at 1:58 Quote
Odd problem. Noticed that my front wheel looked dished over to the NDS, the tyre being visibly closer to one fork leg than the other. Put the wheel in the truing stand to check, and it's perfect, dished correctly.
Wild Enduro tyre is seated properly on both sides, but deflated and inflated twice just to be sure. Stick the wheel back in the fork and it's still off. Fork is a 2020 Lyrik and not been crashed.

WTF is going on?

Posted: Aug 10, 2022 at 2:39 Quote
TimMog wrote:
Odd problem. Noticed that my front wheel looked dished over to the NDS, the tyre being visibly closer to one fork leg than the other. Put the wheel in the truing stand to check, and it's perfect, dished correctly.
Wild Enduro tyre is seated properly on both sides, but deflated and inflated twice just to be sure. Stick the wheel back in the fork and it's still off. Fork is a 2020 Lyrik and not been crashed.

WTF is going on?

1. Have you tried putting the wheel in the truing stand both ways round? I.e. put it in the stand with the disc mount in the left and check the rim falls directly between the feelers, then replace the wheel in the stand with the disc mount on the right and again check the rim falls directly between the feelers. Be sure to adjust nothing on the truing stand while doing this. Often well used stands drift out of alignment slightly, and checking with the wheel in both ways round will highlight this.

2. Does the tyre stay off to one side when the wheel is rotating? Some tyres can develop a bit of a wobble in the tyre carcass that pushes them to one side even when seated correctly, but this would be extremely unlikely to cause a consistent offset. If you have a damaged tyre carcass, you are far more likely to see the tyre wobbling from side to side while it rotates than just being offset to one side for the entire rotation.

3. If neither of the above highlights an issue, then I'd hazard a guess that the fork isnt straight. Try fitting a different wheel to the fork, and/or fitting your current wheel to a different fork, and seeing what happens.

Posted: Aug 10, 2022 at 2:54 Quote
1. Yes, both ways round to check the dishing. It's spot on, wheel is dished perfectly

2. Tyre stays over to one side, no wobble. It is an old tyre though and due to be replaced soon.

3. Will try those, but can't see how the fork has suddenly become wonky

Posted: Aug 10, 2022 at 5:14 Quote
TimMog wrote:
1. Yes, both ways round to check the dishing. It's spot on, wheel is dished perfectly

2. Tyre stays over to one side, no wobble. It is an old tyre though and due to be replaced soon.

3. Will try those, but can't see how the fork has suddenly become wonky

Check your forks dropouts, hub spacers for wear and that your through axle is straight, also try the axle through the dropouts by itself and check it goes in straight and true. Some times loose axles or broken cams eat through the dropout seat messing with the hub/wheel alignment

Posted: Aug 10, 2022 at 5:18 Quote
TimMog wrote:
1. Yes, both ways round to check the dishing. It's spot on, wheel is dished perfectly

2. Tyre stays over to one side, no wobble. It is an old tyre though and due to be replaced soon.

3. Will try those, but can't see how the fork has suddenly become wonky

Thats an odd one for sure. Short of something very odd happening (a wheel bearing collapsing when loaded by axle tension but holding up when in the wheel jig, or similar) then it sounds like the fork is the root of the issue.

Have you tried inserting the wheel into the fork the wrong way round? (disc on the driveside)
If the rim remains offset to the nds, this suggests a fork issue. If the rim is now offset to the ds, this would suggest a wheel issue. Neither is totally conclusive, but it should at least help you determine where the problem lies.

Posted: Aug 10, 2022 at 5:22 Quote
gabriel-mission9 wrote:
adespotoskyli wrote:
gabriel-mission9 wrote:


Just as a random and completely unhelpful anecdote:
My sram mechs have never had any noticeable clutch tension whatsoever. Ever. Straight out of the factory, the clutch achieves nothing.
My shimano mechs have always had pretty good clutch tension. However you can switch the clutch on and off on shimano mechs, and i tend to leave them switched off. I spend quite a lot of time and money keeping my suspension moving as free as possible, so it seems entirely counter intuitive to then purposely attach a clutch to it.
All my bikes have at least a top guide and a n/w chainring. All my bikes that I hammer through rowdy terrain have a top and bottom guide and a hefty chainstay protector. No dropped chains. A perfectly acceptable amount of chainslap noise.
IMO, clutch mechs are essentially pointless.

Dude you are one gem of a mechanic

luckily to anyone who wants to check how clutches on rear mechs work can watch many videos on youtube testing with clutch engage/disengage from both brands, then you can make up your mind

Also chain can be f*cked up on the cassette as well, what's the point if you don't loose the chain from the chain ring but is crossed over between three cogs at the cassette or drop between the last cog and the frame drop out. Ask me how I know.

You can't disengage the clutch on sram mechs. Although this isn't really a problem, as they don't work anyway.

If your chain is dropping off either end of the cassette, then your mech is incorrectly adjusted. Any bike shop will be able to sort this out for you, but if you are inclined to have a go yourself, there are plenty of guides online that will talk you through it. It's a relatively simple job, and a good one to familiarise yourself with if you are just getting into maintaining your own bike.

If your chain is crossed over three cogs at the rear, this will sort itself out as soon as you start pedalling. If it happens regularly, then there is likely something wrong with the spring tension (or b tension adjustment) on your mech. Sram x-horizon mechs are designed in such a way as to pretty well eliminate ghost shifts, and shimano mechs tend to have beasty return springs which again essentially eliminate ghost shifting. So yeah, if it's happening a lot you probably want to investigate whats come out of adjustment.

Back pedalling during more boring bits of trail often leads to the chain dropping out of the lower gears and then crunching back into place when you start pedalling forwards again, so avoid that if possible.

No adjustment can keep the chain from slapping around in the rough, a clutch mech makes that more manageable. Sram clutches work just fine, actually better than shitmano.

But thanks for being very general and stating the obvious, that have nothing to do with clutch vs non clutch mechs. All others being equal.

Posted: Aug 10, 2022 at 5:37 Quote
adespotoskyli wrote:

No adjustment can keep the chain from slapping around in the rough, a clutch mech makes that more manageable. Sram clutches work just fine, actually better than shitmano.

But thanks for being very general and stating the obvious, that have nothing to do with clutch vs non clutch mechs. All others being equal.

Do I know you? You seem very angry...

Posted: Aug 10, 2022 at 6:17 Quote
Ahhh, no no, I'm just intolerant of people deflecting and being precise, pretending they don't understand what they've been asked and randomly spread imprecise info misleading others. Like clutches are useless


 
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