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Andeh

Customer Title
Mar 3, 2020
1,206
1,170
I've got a question for MegaTrail riders: does the suspension behavior (particularly pedaling and leverage rate) change going from Trail to Gravity mode? I'm under the impression that it's just a travel and geo change, not a leverage change. So it will be a bit more active from the increased travel and proportionately greater sag (in terms of mm, not %) but won't be really changing the pedaling platform. I've played around with the Crush/Plush on my Smash, and that's quite different.

I'm puzzling over how I'd do a MegaSmash, trying to balance my ideas of travel balance front/rear with preferred geometry. I'm thinking a 62.5 stroke resulting in 149mm rear travel in Trail for everyday riding should be pretty sweet. Save 159mm Gravity mode for shuttling or really long descents.
 

toodles

ridiculously corgi proportioned
Aug 24, 2004
5,857
5,227
Australia
I'm puzzling over how I'd do a MegaSmash, trying to balance my ideas of travel balance front/rear with preferred geometry. I'm thinking a 62.5 stroke resulting in 149mm rear travel in Trail for everyday riding should be pretty sweet. Save 159mm Gravity mode for shuttling or really long descents.
Whats the geo\travel like on a MegaSmash? Thats a 29F/27.5R yeah?
 

kidwoo

Artisanal Tweet Curator
I've got a question for MegaTrail riders: does the suspension behavior (particularly pedaling and leverage rate) change going from Trail to Gravity mode? I'm under the impression that it's just a travel and geo change, not a leverage change. So it will be a bit more active from the increased travel and proportionately greater sag (in terms of mm, not %) but won't be really changing the pedaling platform. I've played around with the Crush/Plush on my Smash, and that's quite different.

I'm puzzling over how I'd do a MegaSmash, trying to balance my ideas of travel balance front/rear with preferred geometry. I'm thinking a 62.5 stroke resulting in 149mm rear travel in Trail for everyday riding should be pretty sweet. Save 159mm Gravity mode for shuttling or really long descents.

Its absolutely a leverage change which is how you get more travel out of the same length shock. So yes what you're describing is a result of both the geo change and running a more leveraged shock. But since that is also moar travels it works. But yeah its going to be more active pedaling.
 

ianjenn

Turbo Monkey
Sep 12, 2006
3,003
708
SLO
Its absolutely a leverage change which is how you get more travel out of the same length shock. So yes what you're describing is a result of both the geo change and running a more leveraged shock. But since that is also moar travels it works. But yeah its going to be more active pedaling.
Don't worry Dan Baggs used to do a 25 mile loop on his M1 with DH helmet and jeans on and end it by riding a pretty technical trail down here. No bike on the planet bobbed worse than that except maybe a VPP before the wonder shocks they made the help the M1s.......
 

Andeh

Customer Title
Mar 3, 2020
1,206
1,170
Whats the geo\travel like on a MegaSmash? Thats a 29F/27.5R yeah?
Yes, 29F/27.5R. Take these geo numbers with a grain of salt, as they came from me making a CAD drawing with the dimensions listed in the GG published MT geometry chart, then replacing the fork with a 29er fork & wheel, then rotating about the rear tire contact patch to bring the front tire into ground contact. Forks with different A/C from the one I assumed (Fox) will change things. So they're probably +/- 0.2 degree.

60mm stroke: trail mode = 143mm, gravity mode = 152mm
62.5mm stroke: trail mode = 149mm, gravity mode = 159mm
65mm stroke: trail mode = 155mm, gravity mode = 165mm

On all of those:
150mm fork, 44mm rake: trail mode = 64.2 HT, 76.2 ST. gravity mode = 63.7 HT, 75.7 ST
160mm fork, 44mm rake: trail mode = 63.8 HT, 75.9 ST. gravity mode = 63.3 HT, 75.4 ST

Its absolutely a leverage change which is how you get more travel out of the same length shock. So yes what you're describing is a result of both the geo change and running a more leveraged shock. But since that is also moar travels it works. But yeah its going to be more active pedaling.
Durrr, yeah. I should have thought of that. Sounds like I 100% should focus on getting the seat tube angle I want for pedaling in Trail mode. 62.5 stroke and 160 fork is looking good.
 

marshalolson

Turbo Monkey
May 25, 2006
1,774
532
Sounds like I 100% should focus on getting the seat tube angle I want for pedaling in Trail mode. 62.5 stroke and 160 fork is looking good.
This sounds like chasing the right thing!

I would add, you can run a bit less sag on your rear shock to accomplish the same thing (higher ride height while pedaling).

So while the shock at 65mm may not be physically limited to less stroke, it feels essentially the same as a 62.5mm shock if you reduce your sag from, say, 30% to 26%.

I am now running about 25% sag on my Gnarvana (coil shock) and loving it. FWIW.
 
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Rockland

Turbo Monkey
Apr 24, 2003
1,880
286
Left hand path
@marshalolson : Was there a change suspension wise between the aluminum MT and Revved MT? Trail mode was stated as 150mm travel - Gravity was 165mm on the old bikes.

@Andeh : I'm running mullet on my MT ( and really enjoying it), but don't know if any measurements I have would help. Old extra-med size, Works -1 deg headset, 160mm Lyrik 29" 42mm offset
 

mtg

Green with Envy
Sep 21, 2009
1,862
1,604
Denver, CO
@marshalolson : Was there a change suspension wise between the aluminum MT and Revved MT? Trail mode was stated as 150mm travel - Gravity was 165mm on the old bikes.

@Andeh : I'm running mullet on my MT ( and really enjoying it), but don't know if any measurements I have would help. Old extra-med size, Works -1 deg headset, 160mm Lyrik 29" 42mm offset
Yes, the kinematics were modified on the Megatrail between the 2nd gen (AL) and 3rd gen (Revved carbon). There isn't a wholesale change in personality, but the travel was increased in Trail Mode a little bit and progression refined for the 3rd gen.
 

Rockland

Turbo Monkey
Apr 24, 2003
1,880
286
Left hand path
Yes, the kinematics were modified on the Megatrail between the 2nd gen (AL) and 3rd gen (Revved carbon). There isn't a wholesale change in personality, but the travel was increased in Trail Mode a little bit and progression refined for the 3rd gen.
Thanks Matt.

Since I've got you on the line: This year I needed a new shock. LBS got me a new 2021 DHX2. The only aftermarket tune available was D3CZ. As far as I can discern this is a med comp - med reb. It's due to be serviced, and this would be my chance to make some changes. Would you have ordered it built different?
 

Andeh

Customer Title
Mar 3, 2020
1,206
1,170
This sounds like chasing the right thing!

I would add, you can run a bit less sag on your rear shock to accomplish the same thing (higher ride height while pedaling).

So while the shock at 65mm may not be physically limited to less stroke, it feels essentially the same as a 62.5mm shock if you reduce your sag from, say, 30% to 26%.

I am now running about 25% sag on my Gnarvana (coil shock) and loving it. FWIW.
Fair point. Playing with the EXT spring rate formula, increasing the travel by 10mm for one of those stroke lengths looks like it increases sag by about 1.5-2%. So flipping to Gravity with the same spring will not only have more travel but will definitely feel plusher just from that alone. I'm still waiting to hear back from EXT what it takes to convert to 65mm stroke, but it does look like for the same 425# spring rate, a 62.5 MS will have nearly identical sag (in mm) as a 65mm MS. I think the travel limiter might just be a plastic ring under the bottom out bumper that I could (carefully) snip off, saving the trouble of sending it in.
 

mtg

Green with Envy
Sep 21, 2009
1,862
1,604
Denver, CO
Thanks Matt.

Since I've got you on the line: This year I needed a new shock. LBS got me a new 2021 DHX2. The only aftermarket tune available was D3CZ. As far as I can discern this is a med comp - med reb. It's due to be serviced, and this would be my chance to make some changes. Would you have ordered it built different?
Yes, we have a custom tune that works well. I don't have the 4 digit code handy, but will PM you the full tune spec to go with.
 

mtg

Green with Envy
Sep 21, 2009
1,862
1,604
Denver, CO
Fair point. Playing with the EXT spring rate formula, increasing the travel by 10mm for one of those stroke lengths looks like it increases sag by about 1.5-2%. So flipping to Gravity with the same spring will not only have more travel but will definitely feel plusher just from that alone. I'm still waiting to hear back from EXT what it takes to convert to 65mm stroke, but it does look like for the same 425# spring rate, a 62.5 MS will have nearly identical sag (in mm) as a 65mm MS. I think the travel limiter might just be a plastic ring under the bottom out bumper that I could (carefully) snip off, saving the trouble of sending it in.
For stroke limiting coil shocks, you can always DIY something from a stiff rubber sheet. Cut a circle, put a hole in the middle for the shaft, and then slit from center to outside so you can flex it around the damper shaft and put it behind the bottom out bumper. Obviously you'll be in an unofficial compatibility area, so you'll need to check clearances.
 

marshalolson

Turbo Monkey
May 25, 2006
1,774
532
Fair point. Playing with the EXT spring rate formula, increasing the travel by 10mm for one of those stroke lengths looks like it increases sag by about 1.5-2%. So flipping to Gravity with the same spring will not only have more travel but will definitely feel plusher just from that alone. I'm still waiting to hear back from EXT what it takes to convert to 65mm stroke, but it does look like for the same 425# spring rate, a 62.5 MS will have nearly identical sag (in mm) as a 65mm MS. I think the travel limiter might just be a plastic ring under the bottom out bumper that I could (carefully) snip off, saving the trouble of sending it in.
yup!

Same spring on a 62.5 and 65 would have the same sag in mm and about 3.5% less sag as a percentage of stroke.
 

Andeh

Customer Title
Mar 3, 2020
1,206
1,170
Well, I got cold feet on the on the MegaSmash mullet idea the more I stared at BB heights (353+ in Trail) and the cost of a new wheel, and am going to tinker with Gnarvana stays instead.

Marshall, you're running your Gnarvana with a 160 fork right? My biggest complaint with my Smash right now is that it sort of rides high compared to my Sentinel (345 on Sentinel, 350 on Smash with 160 fork). Gnarvana with 160 should be back down to 345. I can't manual for shit anyways, so not worried really about the long CS. Even though I'm 5'8", butt buzz only happens when I screw up.

Oh and EXT said that because the HBC system is set to kick in at a certain percentage of stroke, lengthening stroke is more complicated than just changing a spacer. But I still think I could have them change my shock to 65mm and make my own spacer for when I want to short stroke to 60mm, which would have HBC kick in earlier in the travel, resulting in a bit more progressive shock. Or have SS or DSD custom tune this take-off DPX2 Performance for a 60mm Smash trail bike setup.
 

mtg

Green with Envy
Sep 21, 2009
1,862
1,604
Denver, CO
Well, I got cold feet on the on the MegaSmash mullet idea the more I stared at BB heights (353+ in Trail) and the cost of a new wheel, and am going to tinker with Gnarvana stays instead.

Marshall, you're running your Gnarvana with a 160 fork right? My biggest complaint with my Smash right now is that it sort of rides high compared to my Sentinel (345 on Sentinel, 350 on Smash with 160 fork). Gnarvana with 160 should be back down to 345. I can't manual for shit anyways, so not worried really about the long CS. Even though I'm 5'8", butt buzz only happens when I screw up.

Oh and EXT said that because the HBC system is set to kick in at a certain percentage of stroke, lengthening stroke is more complicated than just changing a spacer. But I still think I could have them change my shock to 65mm and make my own spacer for when I want to short stroke to 60mm, which would have HBC kick in earlier in the travel, resulting in a bit more progressive shock. Or have SS or DSD custom tune this take-off DPX2 Performance for a 60mm Smash trail bike setup.
I've run a 160 fork on a Gnarvana, and like it for the reason you mentioned. It's a good all-rounder.
 

marshalolson

Turbo Monkey
May 25, 2006
1,774
532
Well, I got cold feet on the on the MegaSmash mullet idea the more I stared at BB heights (353+ in Trail) and the cost of a new wheel, and am going to tinker with Gnarvana stays instead.

Marshall, you're running your Gnarvana with a 160 fork right? My biggest complaint with my Smash right now is that it sort of rides high compared to my Sentinel (345 on Sentinel, 350 on Smash with 160 fork). Gnarvana with 160 should be back down to 345. I can't manual for shit anyways, so not worried really about the long CS. Even though I'm 5'8", butt buzz only happens when I screw up.

Oh and EXT said that because the HBC system is set to kick in at a certain percentage of stroke, lengthening stroke is more complicated than just changing a spacer. But I still think I could have them change my shock to 65mm and make my own spacer for when I want to short stroke to 60mm, which would have HBC kick in earlier in the travel, resulting in a bit more progressive shock. Or have SS or DSD custom tune this take-off DPX2 Performance for a 60mm Smash trail bike setup.
yo man!
Sorry to miss this. I have run my fork on the Gnarvana at 150, 160, and 170.

fwiw the BB of my Gnarvana, with a 170 fork, measures 13.5” - so <345mm. this is why I have ended up at 170mm, paired to a 60mm stroke (about 150mm travel) shock.

Super versatile and ride it all over, and for the trails where it is just too big (the ride-from-home shoulder season trails), I have an xc-ish bike for that... and still take the Gnarvana out on them a good bit.
 
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Andeh

Customer Title
Mar 3, 2020
1,206
1,170
yo man!
Sorry to miss this. I have run my fork on the Gnarvana at 150, 160, and 170.

fwiw the BB of my Gnarvana, with a 170 fork, measures 13.5” - so <345mm. this is why I have ended up at 170mm, paired to a 60mm stroke (about 150mm travel) shock.

Super versatile and ride it all over, and for the trails where it is just too big (the ride-from-home shoulder season trails), I have an xc-ish bike for that... and still take the Gnarvana out on them a good bit.
Thanks, that's helpful. My shock's currently at 60mm also, so was going to try that at first. I should actually measure my current BB height for reference.
 

Andeh

Customer Title
Mar 3, 2020
1,206
1,170
Cross posting this from (wince) MTBR.
I love the customization and tuning options that the Revved frames allow. I'm also mullet-curious, so have done some sketches to try and figure out what some different mullet geometries would end up as. I've compiled this in a spreadsheet, and thought I'd share it.

https://docs.google.com/spreadsheets...it?usp=sharing

I think this info should be pretty close, but I'm not a bike designer, so use at your own risk.

I personally started with a 145/160 Smash, and have an order in for some Gnarvana stays to try in a 148/160 aggressive trail mode.
 

mtg

Green with Envy
Sep 21, 2009
1,862
1,604
Denver, CO
@mtg / @marshalolson - how different does cornering feel between the MegaSmash and the Smash given the same fork travel? Does the MegaSmash feel like it has a shorter backend?
I haven't done that specific comparison back to back, but have done Trail Pistol -> MegaSmash -> Trail Pistol. I wouldn't expect a significant difference in cornering feel due to chainstay length between MegaSmash and The Smash. I think whether you're in Trail or Gravity on the Megatrail seatstays with regards to HTA, leverage curve, and rear wheel travel would be the more significant.
 

marshalolson

Turbo Monkey
May 25, 2006
1,774
532
@mtg / @marshalolson - how different does cornering feel between the MegaSmash and the Smash given the same fork travel? Does the MegaSmash feel like it has a shorter backend?
I was thinking about this last night, and obviously, mtg's feedback is more relevant than my own (he has ridden similar), but when looking at a mullet setup, there is no way of getting around the fact the wheel and fork are both bigger. So if you use the flat lower cup, the front end is either +30mm taller than the Megatrail, you need to drop 30mm in travel to maintain it, or you are splitting the difference.

I don't think anyone is actually dropping fork travel that much, so really it's increasing stack, shortening the reach, lifting the BB, slackening the angles, and increasing front-center. For these reasons, I am tracking with mtg's logic, that those and the leverage ratio changes between models are all quite big changes vs. the small mm difference in stay length, all in all.
 

djjohnr

Turbo Monkey
Apr 21, 2002
3,115
1,801
Northern California
I was thinking about this last night, and obviously, mtg's feedback is more relevant than my own (he has ridden similar), but when looking at a mullet setup, there is no way of getting around the fact the wheel and fork are both bigger. So if you use the flat lower cup, the front end is either +30mm taller than the Megatrail, you need to drop 30mm in travel to maintain it, or you are splitting the difference.

I don't think anyone is actually dropping fork travel that much, so really it's increasing stack, shortening the reach, lifting the BB, slackening the angles, and increasing front-center. For these reasons, I am tracking with mtg's logic, that those and the leverage ratio changes between models are all quite big changes vs. the small mm difference in stay length, all in all.
Thanks Marshal and MTG. I'm not so much looking at the CS length, as the difference seems pretty minimal, but more of what it feels like overall when cornering in comparison when considering the sum of all changes (geo and any gyroscopic effect of the wheel). For example, I'd describe running the long headset cup as making the rear end feel comparatively shorter in corners from making fc/rc ratio larger in the direction of fc. Same goes for slackening the head angle, increasing fork travel, running offset bushings etc. Maybe a better way of phrasing it is "does changing to the MT stays/27.5" rear wheel make it feel like you have more leverage over the rear wheel". Looking at the changes I guess it would, but there's obviously no substitute for first-hand experience.
 
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HAB

Chelsea from Seattle
Apr 28, 2007
11,592
2,028
Seattle
I stuck a 27.5" wheel in the back of a Smash (with a 150mm fork, FWIW) for a few rides just for giggles, and it definitely made the rear end feel... smaller, for lack of a better word. I don't mean chainstay length obviously, there was just less going on back there, it turned in harder and was easier to throw around but overall felt sort of unbalanced, like you had to be really aggressive about getting over the front end, and the back was kind of just a rudder.

Obviously some of that had to do with the geo — dropping the rear end lowered the BB, increased stack height, slacked the HTA, etc. FWIW in full 29er mode, I've tried the Smash with a 150, 160 and 170 fork, and liked the 150/160 significantly better than the 170.
 

djjohnr

Turbo Monkey
Apr 21, 2002
3,115
1,801
Northern California
I stuck a 27.5" wheel in the back of a Smash (with a 150mm fork, FWIW) for a few rides just for giggles, and it definitely made the rear end feel... smaller, for lack of a better word. I don't mean chainstay length obviously, there was just less going on back there, it turned in harder and was easier to throw around but overall felt sort of unbalanced, like you had to be really aggressive about getting over the front end, and the back was kind of just a rudder.

Obviously some of that had to do with the geo — dropping the rear end lowered the BB, increased stack height, slacked the HTA, etc. FWIW in full 29er mode, I've tried the Smash with a 150, 160 and 170 fork, and liked the 150/160 significantly better than the 170.
I did a similar test with a 26" wheel in the back of a 27.5 Enduro EVO with the same results as you. So far I've tried combos of short/long headset and 150/160 fork travel and like long/160 the best. High speed corners, chunk, drops and jumps all feel fantastic, but tight/steep/loose combo corners with grade changes could be better. Testing stem lengths right now, have some offset bushings coming and contemplating testing the mullet setup.
 

mtg

Green with Envy
Sep 21, 2009
1,862
1,604
Denver, CO
2020.........lessons not learned from the specialized big hit
There is also a huge difference between putting a 27.5" rear wheel into a bike designed for a 29" rear wheel, vs doing something like using a Megatrail rear end, the zero stack lower headset up with a 29er front end.
 

Cerberus75

Monkey
Feb 18, 2017
520
194
Thanks Marshal and MTG. I'm not so much looking at the CS length, as the difference seems pretty minimal, but more of what it feels like overall when cornering in comparison when considering the sum of all changes (geo and any gyroscopic effect of the wheel). For example, I'd describe running the long headset cup as making the rear end feel comparatively shorter in corners from making fc/rc ratio larger in the direction of fc. Same goes for slackening the head angle, increasing fork travel, running offset bushings etc. Maybe a better way of phrasing it is "does changing to the MT stays/27.5" rear wheel make it feel like you have more leverage over the rear wheel". Looking at the changes I guess it would, but there's obviously no substitute for first-hand experience.
A mullet bike has less need for leverage IMHO. The rear wheel follows the same track as the front vs a larger arc to the outside. Less use of the hips to make it rotate. If that is what you're asking
 

HAB

Chelsea from Seattle
Apr 28, 2007
11,592
2,028
Seattle
There is also a huge difference between putting a 27.5" rear wheel into a bike designed for a 29" rear wheel, vs doing something like using a Megatrail rear end, the zero stack lower headset up with a 29er front end.
For sure, I was just commenting on the thing I've actually tried. And I tried to make it pretty clear that it was a bit goofy. There's a reason I didn't keep doing it.
 

kidwoo

Artisanal Tweet Curator
There is also a huge difference between putting a 27.5" rear wheel into a bike designed for a 29" rear wheel, vs doing something like using a Megatrail rear end, the zero stack lower headset up with a 29er front end.
But the bighit was designed for rear end stupidity from the get go and it still felt stupid. I was just making fun of HAB for his revelations. :D



You guys should build some kind of modular frame platform that allows for things like different rear ends and longer fork a-c dimensions.
 

HAB

Chelsea from Seattle
Apr 28, 2007
11,592
2,028
Seattle
But the bighit was designed for rear end stupidity from the get go and it still felt stupid. I was just making fun of HAB for his revelations. :D
In my defense, I don't think I ever rode one of those.


I still support making fun of me though.