MegNeg

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MegNeg
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Posted: Feb 17, 2021 at 13:48 Quote
Does anyone have experience with a megneg on a 2021 Commencal Meta Power SX? Just got the bike so not a lot of time on it but already noticing on just rides around the block off curbs I am able to blow through the mid stroke and bottom out the stock RS Deluxe. Still need to play with air pressure a bit but waiting on some parts before I take it for a trail ride. Due to the Deluxe being a non reservoir shock I am already looking at the Super Deluxe ultimate with MegNeg or the X2 as I do several trails that will probably overheat this shock if history repeats itself. For a 180/165mm bike the Deluxe is really under damped for such a large capable ebike.

Posted: Feb 17, 2021 at 15:00 Quote
I hear the megneg is a need for the metas not a want.
My friends have them on theirs and have not looked back

Posted: Feb 17, 2021 at 16:51 Quote
Tvaneijk wrote:
I hear the megneg is a need for the metas not a want.
My friends have them on theirs and have not looked back

Do you know if thats the Meta Power (ebike) or the normal Meta? Also I want to say the other Metas (non ebike) come with a super deluxe over the deluxe I have... but not positive.

Posted: Feb 17, 2021 at 20:10 Quote
I have had a megneg on the last Am29 version and have it on my 2021 AM29. Works really well. No reason not to try it for the price and tuning you can do with it.

Posted: Feb 18, 2021 at 10:17 Quote
oldnw wrote:
I have had a megneg on the last Am29 version and have it on my 2021 AM29. Works really well. No reason not to try it for the price and tuning you can do with it.
Are you running a deluxe or super deluxe on your AM?

Posted: Feb 19, 2021 at 7:51 Quote
oldnw wrote:
Super deluxe.
Yeah my bike comes with the Deluxe, just ordered the megneg to try it on the deluxe if it gets me 80% there then I will go ahead and upgrade to the Super Deluxe ultimate as this bike really should not have a non-reservoir style shock. With it being winter I should be fine not hitting hard trails what will overheat it but come summer riding and parks I will need to upgrade to something a bit heavier duty. A coil or X2 is still in the back of my mind but will give this setup a go, I did just get the bike and it hasn't really had time on trails yet.

Posted: Feb 20, 2021 at 13:00 Quote
b-racer wrote:
oldnw wrote:
Super deluxe.
Yeah my bike comes with the Deluxe, just ordered the megneg to try it on the deluxe if it gets me 80% there then I will go ahead and upgrade to the Super Deluxe ultimate as this bike really should not have a non-reservoir style shock. With it being winter I should be fine not hitting hard trails what will overheat it but come summer riding and parks I will need to upgrade to something a bit heavier duty. A coil or X2 is still in the back of my mind but will give this setup a go, I did just get the bike and it hasn't really had time on trails yet.

I have found that 3 bands works best. Seems like any less and it gets really harsh. That’s just me. I am 155-160 kitted.Running 183 psi, 30% sag range, no volume reducers,3 bands. I have a LL tune on my shock though. You most likely have a MM tune.

Posted: Feb 23, 2021 at 2:36 Quote
ThinkTank45 wrote:
My new bike is a 2020 Nukeproof Mega 29.
I rode it first without the megneg, with just a touch under 30% sag and two volume reducers. Initial impression was incredibly plush rear suspension but lacking in support when trying to pump on flatter sections.
I installed the megneg and removed both positive volume reducers, so I'm starting out with no bands or tokens and 30% sag.
Only one ride done so far but it feels good. I may need to add back one positive volume reducer but I will do some more riding before deciding. I find it difficult to judge the rebound damping of the shock with the megneg because of the increased mid stroke support. Usually I can balance the rebound front and rear pretty quickly just by bouncing around the car park but it takes longer with the megneg.

Just in case anyone's interested! I have done a fair bit of riding now with the megneg on my Mega. I am very happy with the current setup (zero negative bands, zero positive reducers, 30% sag.). A great combination of sensitivity and mid-stroke support. Also there is more pop than I was expecting but that may be due to the way I set the rebound damping.

Posted: Feb 25, 2021 at 21:55 Quote
I am wondering if my Kona Satori with a Rockshox Deluxe RL Debonair Trunnion would be a good candidate for the MegNeg? I am only running 20% sag to avoid bottoming out on some Jumps and huck to flats. Yes it can be pretty harsh on chatter which sucks and doesn't seem to have much mid travel support.
It has a 2.8 leverage ratio and it's anti squat stays above 100% through out it's travel.

Posted: Feb 25, 2021 at 23:54 Quote
Grilledcheesetriple,

My opinion is that long, high-volume negative springs, such as the MegNeg, should be the standard and it should be uncommon tuning issues that prompt us to ask whether a short or low-volume negative spring is appropriate.

The average leverage ratio and the anti-squat aren't really factors in deciding on your spring. What matters are how progressive the linkage is and the shape of the curve. In the case of the Satori, it's moderately progressive with a nearly linear curve. Pretty standard stuff - which is a good thing! It's not a bike that urgently needs more mid-stroke support from the spring, but there's nothing to indicate against it, so go for it.

There could be other factors to consider:

• 130 mm isn't a lot to protect against hucks to flat. You may need a highly progressive spring to provide the bottom-out support you need without affecting the rest of the travel. More reducers in the positive spring should help.
• Your sag is low and you're still bottoming out, which suggests more high-speed damping would help.
• Harshness over chatter can be due to a number of factors:
-- Rebound damping: Speed it up as much as possible.
-- Sag: More will help.
-- Compression damping: Reduce the low-speed damping, if possible.

Overall, I think the MegNeg will help by reducing the support in the early part of the stroke, allowing more sag to help with chatter, and helping to create a more smoothly progressive spring rate curve. Depending on your weight, you could get close to the maximum pressure for the shock.

Posted: Feb 26, 2021 at 6:18 Quote
Ok Thank You, I can speed up my rebound but not my compression damping. It's wide open or locked out. Yes I thought the Megneg would would allow me to run more sag which is good. I figured Volume reducers would just make it harsh. I rarely bottom out now with the extra air (20% sag) but have lost some plushness in the top of the stroke. I weigh 155lbs.
R-M-R wrote:
Grilledcheesetriple,

My opinion is that long, high-volume negative springs, such as the MegNeg, should be the standard and it should be uncommon tuning issues that prompt us to ask whether a short or low-volume negative spring is appropriate.

The average leverage ratio and the anti-squat aren't really factors in deciding on your spring. What matters are how progressive the linkage is and the shape of the curve. In the case of the Satori, it's moderately progressive with a nearly linear curve. Pretty standard stuff - which is a good thing! It's not a bike that urgently needs more mid-stroke support from the spring, but there's nothing to indicate against it, so go for it.

There could be other factors to consider:

• 130 mm isn't a lot to protect against hucks to flat. You may need a highly progressive spring to provide the bottom-out support you need without affecting the rest of the travel. More reducers in the positive spring should help.
• Your sag is low and you're still bottoming out, which suggests more high-speed damping would help.
• Harshness over chatter can be due to a number of factors:
-- Rebound damping: Speed it up as much as possible.
-- Sag: More will help.
-- Compression damping: Reduce the low-speed damping, if possible.

Overall, I think the MegNeg will help by reducing the support in the early part of the stroke, allowing more sag to help with chatter, and helping to create a more smoothly progressive spring rate curve. Depending on your weight, you could get close to the maximum pressure for the shock.

Posted: Feb 26, 2021 at 6:42 Quote
Positive spring reducers change only the end of the stroke, so you'll notice little to no difference on most impacts, just the ones that would've otherwise bottomed out the shock.

Try more sag, some positive reducers, and faster rebound before buying the MegNeg. You may be able to find an acceptable set-up without spending any money.

Posted: Feb 26, 2021 at 12:53 Quote
After skimming and reading all of the pages of this thread, and being a big fan of tinkering, I scooped up a Megneg for my V1 Sentinel this past week. This little thing is a hell of a change, and it's pretty cool that Rockshox made this available to the general public.

I had a few questions, more for curiosity than anything else. I really want to understanding the mechanics of what is happening here, and it sounds like there are some really smart people in this thread who can see if I've got it right.

The Megneg can allows you to run a higher static pressure in the positive air chamber by decreasing the amount of force required to move the shock through the first half or so of it's travel by having the larger negative air chamber that basically "helps" the shock move through that travel. Adding negative bands increases this breakaway assistance. This allows you to still have great small bump compliance, but with higher static pressure. True or False?

With this higher static pressure, once the negative air chamber assistance becomes less impactful further in it's travel, the higher static pressure allows that strong mid/end stroke support that wouldn't normally be there at your "regular" shock pressure on the stock can. This is what allows that mid/end stroke support. True or False?

If you had to explain this to your Grandmother, would you say that the Megneg allows a lighter rider (like me, 160# full kit) to run a higher pressure for mid/end stroke support on very linear bikes, but maintain that small bump compliance that would disappear if you tried to run that higher static pressure in the stock can?

That's what I'm seeing in my head as I work it through. And really, I shouldn't care about how it works. I just know that it does, I'm just a suspension nerd.

Also, V1 Sentinel, 160#, 2 neg, 1 posi, 170PSI, still testing

Posted: Feb 26, 2021 at 13:22 Quote
sclay115 wrote:
After skimming and reading all of the pages of this thread, and being a big fan of tinkering, I scooped up a Megneg for my V1 Sentinel this past week. This little thing is a hell of a change, and it's pretty cool that Rockshox made this available to the general public.

I had a few questions, more for curiosity than anything else. I really want to understanding the mechanics of what is happening here, and it sounds like there are some really smart people in this thread who can see if I've got it right.

The Megneg can allows you to run a higher static pressure in the positive air chamber by decreasing the amount of force required to move the shock through the first half or so of it's travel by having the larger negative air chamber that basically "helps" the shock move through that travel. Adding negative bands increases this breakaway assistance. This allows you to still have great small bump compliance, but with higher static pressure. True or False?

Because the megneg has a much larger negative chamber than usual, in order to achieve the same sag as your old shock, you have to run a higher air pressure. Adding negative bands makes the negative chamber smaller, so in fact does the opposite of what you said above.
The large negative chamber helps to reduce the force required to move the shock through the first few mm of its travel.


With this higher static pressure, once the negative air chamber assistance becomes less impactful further in it's travel, the higher static pressure allows that strong mid/end stroke support that wouldn't normally be there at your "regular" shock pressure on the stock can. This is what allows that mid/end stroke support. True or False?

The increased pressure used to achieve the sag level required as compared to the stock shock is what provides the mid/end stroke support.

If you had to explain this to your Grandmother, would you say that the Megneg allows a lighter rider (like me, 160# full kit) to run a higher pressure for mid/end stroke support on very linear bikes, but maintain that small bump compliance that would disappear if you tried to run that higher static pressure in the stock can?

Yes, a higher pressure in comparison the the stock shock if both are set to the same sag.

That's what I'm seeing in my head as I work it through. And really, I shouldn't care about how it works. I just know that it does, I'm just a suspension nerd.

Also, V1 Sentinel, 160#, 2 neg, 1 posi, 170PSI, still testing


 
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