Is the 29 / 27.5 combo (97.5) bike here to stay?

Related:
Bike Setup
Racing
29er
27.5
Question
jeff.brines
Profile picture for user jeff.brines
Posts
1233
Joined
8/29/2010
Location
Grand Junction, CO US
jeff.brines 8/23/2019 1:25pm
8/23/2019 1:25pm Edited Date/Time 8/23/2019 1:26pm
sspomer wrote:
[img]https://p.vitalmtb.com/photos/forums/2019/08/23/8372/s1200_spectral69.jpg[/img] i 69'd / mulleted / mixer'd / 279'd / 97.5'd a canyon spectral for our crankworx whistler trip just to see what it would be...


i 69'd / mulleted / mixer'd / 279'd / 97.5'd a canyon spectral for our crankworx whistler trip just to see what it would be like. originally 27.5 front and rear with 160mm fork and bars pretty high, i put a 29er fork with 150mm travel and was able to keep bar height the same. head angle changed (IIRC it went to 64.5) and bb went up a bit, but i didn't measure that. assegai DH tire up front, DHR II exo (stock tire) out back.

i had a BLAST on it riding lifts at whistler. riding natural black trails like no joke or angry pirate or too tight, was really fun as were the natural/tech blue trails like blueseum, funshine, samurai pizza cat, karate monkey cat. the big front wheel and slacker HA was was good for holes and any roll-in kinks, but there was a playfulness out back and it could lean easily. i wouldn't get stood up in corners like a dual 29er (i also rode my norco fluid 29er (140/120 travel with DH tires) the day before on the same trails to compare. it was also really fun, but harder to change direction in tight corners). i'd listened to brendog's Outspoken the night before and swear i drank his kool-aid about the setup.

i'm not much of a jumper, i'll hit crank it up and stuff and have fun on those hits, but i'm not whipping or kicking out. On the chatter bumps of those groomers, the back end seemed less planted than my norco 29er, but it could just be the rear tire too (non-DH casing/rubber and pressure was up a bit b/c i was paranoid about flatting the EXO). i'm surprised at how fun it was on lift-served DH. i thought it would be goofy and awkward, but it wasn't in that environment. w/ that said, it wouldn't be too fun on my home trails which aren't steep or very technical...even with a lighter front tire. pedaling around was a little weird too, but i didn't try to fine tune anything (saddle position) for pedaling. if it was all i had, i'm sure i'd get used to it.
Did the same thing to my gfs bronson. She loves it. It works so well for her, especially being under 5'6". She has more confidence but isn't getting buzzed off the back when it gets steep. I think there is something to it. I also like the fact you can pull some rotating weight off the bike without doing something silly (smaller wheel = lighter weight).

I would have gone 160 or 170 on that thing for Whistler though! HA would have been good and who cares about the BB when your hands are just getting schammered all day.
Teeejaaay
Profile picture for user Teeejaaay
Posts
3
Joined
1/22/2019
Location
Oceanside, CA US
Teeejaaay 8/23/2019 1:34pm
8/23/2019 1:34pm
Welcome to the dark side @sspomer
1
JVO
Profile picture for user JVO
Posts
9
Joined
10/31/2017
Location
Central, CA US
JVO 8/23/2019 3:03pm
8/23/2019 3:03pm Edited Date/Time 8/23/2019 3:14pm

Here is my Yeti SB 165 in "97.5". I am LOVING this bike. Exactly what was said about turns - able to dive in and out much quicker than full 29" - to me anyway. This set up is Really fast and fun!





2
sspomer
Profile picture for user sspomer
Posts
6124
Joined
6/26/2009
Location
Boise, ID US
Fantasy
54th
sspomer 8/23/2019 6:00pm
8/23/2019 6:00pm
sspomer wrote:
[img]https://p.vitalmtb.com/photos/forums/2019/08/23/8372/s1200_spectral69.jpg[/img] i 69'd / mulleted / mixer'd / 279'd / 97.5'd a canyon spectral for our crankworx whistler trip just to see what it would be...


i 69'd / mulleted / mixer'd / 279'd / 97.5'd a canyon spectral for our crankworx whistler trip just to see what it would be like. originally 27.5 front and rear with 160mm fork and bars pretty high, i put a 29er fork with 150mm travel and was able to keep bar height the same. head angle changed (IIRC it went to 64.5) and bb went up a bit, but i didn't measure that. assegai DH tire up front, DHR II exo (stock tire) out back.

i had a BLAST on it riding lifts at whistler. riding natural black trails like no joke or angry pirate or too tight, was really fun as were the natural/tech blue trails like blueseum, funshine, samurai pizza cat, karate monkey cat. the big front wheel and slacker HA was was good for holes and any roll-in kinks, but there was a playfulness out back and it could lean easily. i wouldn't get stood up in corners like a dual 29er (i also rode my norco fluid 29er (140/120 travel with DH tires) the day before on the same trails to compare. it was also really fun, but harder to change direction in tight corners). i'd listened to brendog's Outspoken the night before and swear i drank his kool-aid about the setup.

i'm not much of a jumper, i'll hit crank it up and stuff and have fun on those hits, but i'm not whipping or kicking out. On the chatter bumps of those groomers, the back end seemed less planted than my norco 29er, but it could just be the rear tire too (non-DH casing/rubber and pressure was up a bit b/c i was paranoid about flatting the EXO). i'm surprised at how fun it was on lift-served DH. i thought it would be goofy and awkward, but it wasn't in that environment. w/ that said, it wouldn't be too fun on my home trails which aren't steep or very technical...even with a lighter front tire. pedaling around was a little weird too, but i didn't try to fine tune anything (saddle position) for pedaling. if it was all i had, i'm sure i'd get used to it.
jeff.brines wrote:
Did the same thing to my gfs bronson. She loves it. It works so well for her, especially being under 5'6". She has more confidence but...
Did the same thing to my gfs bronson. She loves it. It works so well for her, especially being under 5'6". She has more confidence but isn't getting buzzed off the back when it gets steep. I think there is something to it. I also like the fact you can pull some rotating weight off the bike without doing something silly (smaller wheel = lighter weight).

I would have gone 160 or 170 on that thing for Whistler though! HA would have been good and who cares about the BB when your hands are just getting schammered all day.
well, i didn't have a choice on fork, i just happened to have it and the wheel handy. i also think more than 150 would have been too goofy. dug up photos of comparison. it got pretty high in the front. also an extra 10mm wasn't the reason i wasn't riding faster : ) it's back to stock, but it was fun.


i also did it to my norco fluid at home using the spectral back wheel at 27.5 and the intense primer S 27.5+ wheel. took a run on each at home (not whistler) just to see. the regular 27.5 was pretty darn low. the 27.5+ felt more "right" as far as setup, but i didn't like the tire much. just too grippy i think. i wrote angle tweaks and stuff down. i'll dig 'em up later.




all this stuff is super fun to play with. i have some other combos i'm going to try just for kicks...even if they don't make sense.
bulletbass man 8/23/2019 6:26pm
8/23/2019 6:26pm
I finally tried it and though if I was a serious racer i’d Stick with 29 but as an idiot on two wheels there’s nothing better. More front wheel for better maneuvers and less back wheel for getting drifty and popping off features. Kind of funky I’d the air but that would just take some getting used to.
Verbl Kint
Profile picture for user Verbl Kint
Posts
590
Joined
9/13/2013
Location
Quezon City PH
Verbl Kint 8/29/2019 9:10am
8/29/2019 9:10am


w4s
Profile picture for user w4s
Posts
275
Joined
9/2/2009
Location
Verdi, NV US
w4s 8/29/2019 9:35am
8/29/2019 9:35am




This was my mixed wheel bike, Turner DHR with 27.5F/26R. Pretty sure a bike like the new Yeti SB165 with a 29F would be my ultimate trail bike.


1
sspomer
Profile picture for user sspomer
Posts
6124
Joined
6/26/2009
Location
Boise, ID US
Fantasy
54th
sspomer 8/29/2019 9:41am
8/29/2019 9:41am
w4s wrote:
[img]https://p.vitalmtb.com/photos/forums/2019/08/29/8411/s1200_dhr2.jpg[/img] This was my mixed wheel bike, Turner DHR with 27.5F/26R. Pretty sure a bike like the new Yeti SB165 with a 29F would be my...




This was my mixed wheel bike, Turner DHR with 27.5F/26R. Pretty sure a bike like the new Yeti SB165 with a 29F would be my ultimate trail bike.


that's rad! how long ago did you ride it?
w4s
Profile picture for user w4s
Posts
275
Joined
9/2/2009
Location
Verdi, NV US
w4s 8/29/2019 10:31am
8/29/2019 10:31am
w4s wrote:
[img]https://p.vitalmtb.com/photos/forums/2019/08/29/8411/s1200_dhr2.jpg[/img] This was my mixed wheel bike, Turner DHR with 27.5F/26R. Pretty sure a bike like the new Yeti SB165 with a 29F would be my...




This was my mixed wheel bike, Turner DHR with 27.5F/26R. Pretty sure a bike like the new Yeti SB165 with a 29F would be my ultimate trail bike.


sspomer wrote:
that's rad! how long ago did you ride it?
Sold it in 2016 for a new Tues.
Losifer
Profile picture for user Losifer
Posts
407
Joined
9/12/2017
Location
Sandia Park, NM US
Fantasy
957th
Losifer 9/8/2019 8:07pm
9/8/2019 8:07pm Edited Date/Time 9/8/2019 8:10pm
As both an old guy as well as a hardtail guy, I might be out of place in this discussion, but I happened to have a 27.5”, 35mm iw rim and a DT 350 hub sitting unloved in the garage.

Laced it up and put it on the back of a Chromag Rootdown with 150mm Fox 36 and a 2.6” DHF on the front. In just a couple of rides, i’m pretty impressed. On one pedally 2 1/4 mile downhill with lots of corners, I beat my previous best time (2.5” DHF WT on the rear) by 32 seconds.

Then yesterday, I had a fairly big ride on old-school, rough, twisty, rocky alpine trails, and it felt really good. Climbing rocky, tight switchbacks was easier with the additional traction, and the little bit of extra cush was nice!




2
thegromit 9/9/2019 7:26pm
9/9/2019 7:26pm
Does any one know -

If you have a full 29er and put a 27.5 on the back how much does your BB drop and how much slacker is your head angle.

From what I've read its about 18mm difference so is your BB 18mm lower and your head angle about -1.5°

brash
Profile picture for user brash
Posts
947
Joined
4/24/2019
Location
AU
brash 9/9/2019 7:43pm
9/9/2019 7:43pm Edited Date/Time 9/9/2019 7:45pm
when I mullet'ed my e-bike (27.5 x 2.8 plus tyred) I put a 29 x 2.5 assegai and a 27.5 x 2.4 Dissector up back, head angle got 0.8 slacker and BB stayed essentially the same within a millimetre or so when compared to stock geo.

The bike is a beast now, monsters over rocks but turns on a dime. That assegai and dissector combo is a real good one!

But to answer your question, you can plug in the values here to get a good idea.

https://bikegeo.muha.cc/
1
thegromit 9/9/2019 8:49pm
9/9/2019 8:49pm
brash wrote:
when I mullet'ed my e-bike (27.5 x 2.8 plus tyred) I put a 29 x 2.5 assegai and a 27.5 x 2.4 Dissector up back, head...
when I mullet'ed my e-bike (27.5 x 2.8 plus tyred) I put a 29 x 2.5 assegai and a 27.5 x 2.4 Dissector up back, head angle got 0.8 slacker and BB stayed essentially the same within a millimetre or so when compared to stock geo.

The bike is a beast now, monsters over rocks but turns on a dime. That assegai and dissector combo is a real good one!

But to answer your question, you can plug in the values here to get a good idea.

https://bikegeo.muha.cc/
I've used that calc before but I don't understand how I would account for a rear wheel drop, it seem better for angleset calc
sspomer
Profile picture for user sspomer
Posts
6124
Joined
6/26/2009
Location
Boise, ID US
Fantasy
54th
sspomer 12/23/2019 2:58pm
12/23/2019 2:58pm
everyone in this forum thread has been inspirational as i played w/ a bunch of mullet setups. verbl for sure! i put this vid up today. mullet stuff starts around 8:50 (but the whole show is fun : )
https://www.youtube.com/watch?v=QeoZxGpDTXQ
1
dustyyoungblood 12/26/2019 1:32pm
12/26/2019 1:32pm
I've commented on other threads extensively about how much I enjoy my 2016 Foes Mixer. 160mm DVO diamond up front, 152mm travel DVO rear. The GEO is slightly dated, but even that I've not demo ridden a bike I've liked better.

3 years ago, having never ridden a mixed wheel bike, and coming from the 26" world..... Id say it was a "risk" to buy. But the performance was instantaneous and felt comfortable immediately. It's contagiousness to, just left your friends ride it. and it's just really FUN to ride. In three years I've only went OTB once, and it was slow speed and my error. Go back to 26" days and that's a more frequent danger. In 2-3 years its just going to be normal that most all MTB are 29/27.5. Its just silly they are not all now.
colby
Profile picture for user colby
Posts
6
Joined
11/30/2014
Location
CA
colby 6/5/2020 6:47pm
6/5/2020 6:47pm
tubeofcaulk wrote:
I’ve really enjoyed the recent crop of longer travel 29ers. My only issue is that at 5’10 but with a VERY short inseam (<30”), i buzz...
I’ve really enjoyed the recent crop of longer travel 29ers. My only issue is that at 5’10 but with a VERY short inseam (<30”), i buzz the tire on steeps quite easily (which also occasionally happens at seams on big rock slabs for me, as well).

I’d like to see theability to run a 27.5 rear if possible.
EBlackwell wrote:
I have a similar issue on my Sentinel (I'm 5'9" with a similar inseam). However, I think there are a few things that mitigate this. Longer...
I have a similar issue on my Sentinel (I'm 5'9" with a similar inseam). However, I think there are a few things that mitigate this. Longer reach figures, which put you more central on the bike (as opposed to the hanging off the back that comes with short reaches) and longer chainstays, which also allow for a more neutral position for similar reasons.That said, while I do buzz every once and while, I don't really find it to be a major problem. I've never buzzed my rear wheel and had any real issue as a result, other than being somewhat surprised/distracted for a couple seconds.
Hmmmmmmmmm what you all think now 💭? 27.5 in back rules ! Won’t high side ya quicker stiff in the corner, more but clearance
O-Cheez
Profile picture for user O-Cheez
Posts
2
Joined
6/9/2020
Location
CA
O-Cheez 6/9/2020 2:26pm
6/9/2020 2:26pm
I have been interested in this for a while now and recently put a 160mm 29 lyrik on my 2016 SB6 it took quite some time to dial in, I went from a 2018 debonair 160 air spring (too long chopper like) to a 2019 debonair 2 150 air spring (too short on travel and only .5 HA difference) and settled on a 2019 debonair 2 160 air spring I found that the Debonair 2 with its loss of travel 5-7mm (the air spring sits sucked down the 5-7mm lots of forums have way more info) puts me at about 155-153mm up front with the 152mm out back, the overall increase in height with axel to crowna snd 29in wheel was +35mm, I went to a slamset and was able to drop the bar height 25mm, about 10mm in height difference in the end. So far I love it changes the HA from 65.5 to 64 and the big wheel up front changes the ride substantially really notice the ability to carry speed through chunder and rougher trails but corners very well still. bb came up by 10mm but haven't noticed much of a difference, climbing is still good but took some time to adjust the geo changes. Also I don't care so much about how efficient or how well it climbs for the most part, I'll suffer through if it makes for better descending. Haven't noticed a crazy change in strava times but have been quicker for the most part since the change. I would recommend to more aggressive riders/racers who are looking for a little more out of their 27.5 bike depending on current geo and don't want to go full 29. The geo caluclator was a big help in figuring out how possible this was going to be. https://bikegeo.muha.cc/



*seat angle is off a degree in the geo pic should have been originally 73 and now 71.5
rockchomper
Profile picture for user rockchomper
Posts
174
Joined
12/19/2019
Location
Rancho Cucamonga, CA US
rockchomper 6/9/2020 2:37pm
6/9/2020 2:37pm
https://www.vitalmtb.com/news/press-release/Specialized-Officially-Intr…

as a person who is 5,5 and my wife is 5,2 it sucks to see that the sizing on the mullet demo is soo big! We are both to short for a full 29er so the mullet opened the door for us to get on bigger wheel bikes but with the super long reach im not sure it'll work, guess ill have to demo one to see. Does anyone know if they are doing demos on this bike?
bulletbass man 6/10/2020 12:50am
6/10/2020 12:50am
rockchomper wrote:
https://www.vitalmtb.com/news/press-release/Specialized-Officially-Introduces-a-Mixed-Wheel-Demo-DH-Bike,3640 as a person who is 5,5 and my wife is 5,2 it sucks to see that the sizing on the mullet demo is soo big...
https://www.vitalmtb.com/news/press-release/Specialized-Officially-Intr…

as a person who is 5,5 and my wife is 5,2 it sucks to see that the sizing on the mullet demo is soo big! We are both to short for a full 29er so the mullet opened the door for us to get on bigger wheel bikes but with the super long reach im not sure it'll work, guess ill have to demo one to see. Does anyone know if they are doing demos on this bike?
Perhaps size 2 will be in stock soon?

I hear Santa Cruz is releasing a mullet v10 sometime this year. Pretty Sure they’ll have quite a few size options.

Post a reply to: Is the 29 / 27.5 combo (97.5) bike here to stay?