Rail Mullet

[RustyMojo]

The measure to be entered is in millimeters (here in europe....) and the "development in length of the wheel" fits perfectly into the parameters of the kiox (then i take photo with the exacly measure that i put in kiox.... that i don't remember exactly)

It’s the same here buddy. Unless you have something very different to several others who have posted here and many more threads. There is only a 5% adjustment range built into Kiox and it does nothing other than adjust the speed reading. Any other change outside of that the system needs plugging in at a Bosch dealer I believe. I use Raceco cycles now and he isn’t actually sure if it can be changed.

 

[Doomanic]

It can be. I had mine done by Two Wheels in Stourbridge.

 

[Chris79ita]

Taken by making a mark on the ground and spinning the wheel .... just to be specific...) the adjustable "pitch" is from 2009 to 2220 .....

Taken while i was on top (due to the crushing due to the weight) and, as you can see, ...i set it to 2190

Controlled the speed (which, i repeat to be the only parameter that the different wheel affects) is perfect!

Ps: however the test with the garmin speed was made by my dealer ..... who always goes out with us

 

[RustyMojo]

It must be different in your country then. Certainly it’s confirmed in the U.K. that there is a 5% adjustment via the Kiox to allow for adjustment of speed accuracy. I measured both my 29x2.6 rolling circumference and my 27.5x2.6 circumference and the difference was outside of the range for a 2021 Kiox and 2021 Trek Rail.
Just checking with this forum clearly shows this is the case and to align correctly needs plugging into the the Bosch diagnostics system, as such dealer only. So I’m not sure why yours is different, unless the parameters were incorrectly set from new. But I don’t believe that to be the case. However I can confirm I can’t adjust mine and neither, does it seem can others….

 

[Chris79ita]

I don't know if it could depend on the kiox update (which happened before my purchase of the 9.7 rail 2022) ... but it could be because the kiox CPU update can only be done by the dealer (i don't know when exactly with my9.7 ..... to date with the superior models it can be done from the app)

However i guarantee you that the regulation based on the speed is perfect; Sunday i'll check again .... but I'm sure that is ok after the last exit...)

 

[RustyMojo]

My bike has the latest software, it was new in October. I don’t believe my speed is too far out anyway. But to be honest I never look at it as it’s irrelevant really to me.

 

[Gman086]

The 2022's have different kiox parameters which allow for the mullet wheel size change at home as Chris has done from what I understand. According to Doomanic, older models can still get that changed but you'll need the dealer to make the change. That's good news as I'm fairly certain I'll be going that route on my '21 Rail as I have the dreaded "short leg" disease with a 30" inseam. I'm tired of tire marks on my ass, LOL!

Have FUN!

G MAN

 

[Doug Stampfer]

The arse rub is prob the only thing I don't like about the Rail. Has mulleting them stopped that for you guys?

 

[Philly G]

The arse rub is prob the only thing I don't like about the Rail.

Don't forget the colour!

 

[Doug Stampfer]

Don't forget the colour!

Ha! I was thinking that as I wrote it Some of the repaint wore off from the rack exposing the hideous stock paint. Luckily the original paint is so crap it has worn staight through to Ali.

 

[Philly G]

Luckily the original paint is so crap it has worn staight through to Ali.

You could polish the whole bike back to raw ali, would look mean as

 

[Doug Stampfer]

You could polish the whole bike back to raw ali, would look mean as

Takes me back to the days when I used to lust after the GT Zaskar

 

[Doomanic]

I’ve got one of those; a 1995 ex-team Zaskar LE.

 

[Doug Stampfer]

I’ve got one of those; a 1995 ex-team Zaskar LE.

Now that's just bragging! Has it got the stock 200mm long stem - that was the answer to arse rubbing back in the day

 

[Doomanic]

No, I bought it as frame only from the UK race team manager.

 

[Doug Stampfer]

OK any long term feedback? You guys that changed to mullet still loving it? After riding my wifes new mullet bike I'm pretty set on changing mine now. Be interested to hear any downsides.

 

[torabora851]

OK any long term feedback? You guys that changed to mullet still loving it? After riding my wifes new mullet bike I'm pretty set on changing mine now. Be interested to hear any downsides.

Yeah, would be nice to get some review, I'm concerned about bb drop, which by my estimate will drop to 45mm, seems pretty low

 

[Doug Stampfer]

I tried with my Giant rear wheel along the driveway & there's a 40mm difference in the tyre size but not sure how it goes with the mino link in high position. Maybe I'll swap the magnet over & have a test ride. Only problem is the Giant has a 11speed cassette so might be abit of graunching going on. Also the brake pads on ly hit the top of the rotor.... I can see a bit of carnage on the track

 

[Doug Stampfer]

I did bit of a mullet trial today. I used the rear wheel off my Giant trance analogue bike, swapped the brake rotor & magnet & set it up.
I took some measurements while I was doing it in case anyone was interested in the results. There are some comparitive measurements with the wifes Merida E160 -700 that inspired me to mullet mine.

Ground to rear axle- Rail
29.0in 380mm, stock
27.5in 355mm (low position mino link)
27.5in 360mm (high position mino link)
27.5in 360mm - Merida E160 -700

Bottom of pedal to ground -Rail
29.0in 175mm stock
27.5in 155mm (low position mino link)
27.5in 160mm (hih position mino link)
27.5in 165mm - Merida E160-700

Chainstay length ctc 450mm rail, 440mm E160
front to rear axle Rail 1245mm E160 1225mm
By eyeometer the forks looked pretty similar rake

The test ride was over a few different tracks. The 11speed casstte with 12speed shifting was actually not too bad. I timed the shifts ahead of time so was pretty careful not to change under load. I was expecting to have more pedal strikes however tried to ride it as normally as possible to get an accurate comparison.
I could definitely feel the difference riding up. Felt slightly more upright than usual & the tight uphill corners were easier to get around.
1st track was flowy berm with a couple of easy jumps. Noticed straightaway it turned in quicker mid berm if I was over cooking it.
The following tracks were rooty off camber & often dry powder slippery. A few corners into it I settled into the groove & it began to feel very similar to the Merida. More front wheel style riding & the back just followed obediently through ruts & around roots.
During a couple of sketchy drop corners where I thought I may lose the front in the loam I found I could flick the rear round pretty impressively. This may however had been aided by the reasonably worn rear tyre.
The mullet setup inspired in me quite a lot of confidence on the downhills & when I finished at the bottom without the usual adrenaline shakes I knew I was pretty much onto a winner.

The next track was a long twisty climbing track. Only had one corner I couldn't get around but may have come in too hot.
I finished on a long flow bermed track which TBH could've been ridden well on a Raleigh 20 however I let loose & again the flickabilty mid berm saved a few bad line choices.

So in conclusion I'm really pleased with the experiment & I find the Rail mullet setup great. There was prob only one pedal strike which isn't bad, tight uphill corners way easier, more confidence on the downhills with a greater ability to whip the rear around although seldom needed. I felt no loss of stability that is a concern for some, it felt just the same going flat out fast as with the 29in. I think the only concern is a couple of tracks I ride have rock shelfs to drop off. I might have to approach those with a bit more launch technique.
So I feel better now sacrificing my 29 rim & building a 27.5 wheel using my existing hub & brake setup

 

[Philly G]

@Doug Stampfer great review, good to know you're happy with the mullet setup, interesting measurement comparisons with the Merida. I'd be interested to know as well what the head angle is in mullet form with the flip chip set to high...is it similar to stock ?

 

[Doug Stampfer]

@Doug Stampfer great review, good to know you're happy with the mullet setup, interesting measurement comparisons with the Merida. I'd be interested to know as well what the head angle is in mullet form with the flip chip set to high...is it similar to stock ?

Good point but I'm not sure how to measure it easily. There must be a trek chart somewhere. I'm also unsure of how changing the wheel size affects the motor controller etc & if it's worth getting it changed over.

 

[Philly G]

@Doug Stampfer I think with the smaller wheel your mileage will not be accurate and your assistance will drop out earlier - the computer will think youre doing 32kmh but your actual speed will be less than that. You can get an angle meter app on your phone which will measure the head angle close enough

 

[torabora851]

@Doug Stampfer Great review! Interesting, It seems everyone who tried mullet likes it and is going to keep it, but manufacturers still prefer to make niners, and The best eMTB of 2022 - Group test of the 13 hottest eMTB models of the year states that 27.5 is dead for emtb

 

[JP-NZ]

@Doug Stampfer Great review! Interesting, It seems everyone who tried mullet likes it and is going to keep it, but manufacturers still prefer to make niners, and The best eMTB of 2022 - Group test of the 13 hottest eMTB models of the year states that 27.5 is dead for emtb

Its funny that so many people on this forum talk about 27.5, when as many magazines state for "mountain bikes (not EMTB) 27.5 is effectively dead. Over 80% of 2022 MTBs are 29" people talk of 27.5" wheels going the way of the 26" wheel.

The only reason I could see for someone having a full 27.5 wheeled MTB after 2020 is if they are short (under 165cm). Ive ridden and raced MTB's for the better part of 15 years and there is no doubt in my mind that up and down hills and everything in-between 29" is faster the majority of the time. Mullet can be a good change for certain tighter and steeper trails though.

Of course some people will chose the fun factor over all out speed.

 

[Doug Stampfer]

Its funny that so many people on this forum talk about 27.5, when as many magazines state for "mountain bikes (not EMTB) 27.5 is effectively dead. Over 80% of 2022 MTBs are 29" people talk of 27.5" wheels going the way of the 26" wheel.

The only reason I could see for someone having a full 27.5 wheeled MTB after 2020 is if they are short (under 165cm). Ive ridden and raced MTB's for the better part of 15 years and there is no doubt in my mind that up and down hills and everything in-between 29" is faster the majority of the time. Mullet can be a good change for certain tighter and steeper trails though.

Of course some people will chose the fun factor over all out speed.

Yep 29 is prob faster if going faster is your goal. I'm faster on a mullet as an effect of being more manoveurable on the tight trails I like to ride the same way I became faster swapping my rear shock to something better & having more braking & control when I need it. It wasn't a goal to become faster but a byproduct of the change. And when I say fast, well that's how I feel I am until some snot nosed 14 year old rides past me like I'm standing still then goes & pops off roots & shralps his way into the distance .
I don't advocate mullets for everyone & there definitely are the downsides. I've talked to better riders than me who have tried them & then gone back However I'm finding they do work for me and I'm enjoying them. It's like having a new bike & I can always go back if I change my mind.

 

[JP-NZ]

Yep 29 is prob faster if going faster is your goal. I'm faster on a mullet as an effect of being more manoveurable on the tight trails I like to ride the same way I became faster swapping my rear shock to something better & having more braking & control when I need it. It wasn't a goal to become faster but a byproduct of the change. And when I say fast, well that's how I feel I am until some snot nosed 14 year old rides past me like I'm standing still then goes & pops off roots & shralps his way into the distance .
I don't advocate mullets for everyone & there definitely are the downsides. I've talked to better riders than me who have tried them & then gone back However I'm finding they do work for me and I'm enjoying them. It's like having a new bike & I can always go back if I change my mind.

Oh not pointing the finger in anyway. Ride the setup that is best for your local trails. If mullet works for you then thats great

 

[#lazy]

Yes. Don't forget to swap the magnet and brake rotor over as well...

Probably, you'll have to try it and see. My Rail is a 2020 with the 2021 airshaft so is probably about 20mm taller than stock. If you have a Zeb I think they are longer than Yari/Lyrik forks.

Cons; pedal strike more likely. Looks a bit odd with all that space between the rear tyre and frame. Not as good up really steep stuff, but I hate climbing anyway, so real loss to me.
Pros; seems to turn in better, even though the bike is (a lot) slacker than stock.

I'm actually trialling a 27.5 front as well, still in the High position because of the longer forks. Only had a couple of rides so far. First was awful; loads of pedal strikes (compared to the practically none of the mullet set-up) and I don't really like plus or DHF tyres and the wheel I had in the shed was both... Second was much better, able to push on a bit and by the third I was pushing the front hard enough to want something with more grip so I bought a 2.6 Magic Mary (no doubt someone will tell me that's a plus size, but it's a skinny fucker compared to the 2.8 DHR I took off) but then my chain snapped for the third time so after 2200 miles I decided it was time to replace it but the ride was over after 400m. The bike is currently in the shop getting the frame bearings replaced so I'll be able to report back after that's done and I've got a few more rides in.

Yo dom , I got a 27.5 zeb 180mm made to fit a rail ( long story ) if you’re interested….going cheap !

 

[Doomanic]

Yo dom , I got a 27.5 zeb 180mm made to fit a rail ( long story ) if you’re interested….going cheap !

I’m about to put the Rail up for sale, but thanks anyway.

 

[Doug Stampfer]

Just reading through your post
I was curious as to where you measured to get the results above as the ground to rear axle measurement wont alter with the flip chip only tyre profile would alter this measurement
Did you mean something else ?

Thats a good point. You're correct the rear axle wouldn't be affected by the mino link. I'm wondering if I took the pedal height difference & assumed the axle would be raised the same amount. Not a particuarly sound scientific method!!
I have installed my new final rear wheel so will see if there's a difference as the new tyre is a WT which I take is wide tread which may lower the height a bit more than a older non WT tyre.

 

[Gman086]

I swapped to a mullet on my 2021 Rail and these are my observations...

The good:
1. Ground clearance in the "high" position is NOT an issue. My pedal height is taller than on my Yeti SB130 so... no issues.
2. Climbing is actually better for me... this is because the reach gets shortened and I can pull my weight more forward now (short legs, long torso so YMMV). Also the smaller rear wheel is like gearing down... you definitely do NOT need a 50 tooth cog (I'll likely go to 11 speed when drivetrain wears out).
3. Berms are a riot, trust the tires and SNAP that berm!
4. Jumps and drops are way more confident but this is in large part because of ass clearance and knowing I won't be slamming my junk on the rear tire (the biggest reason I went to mullet) because of my short 30 inch inseam. Again, YMMV.
5. Mullet shines in the steep and deep and for FR. When trail pitch gets really steep the mullet won't slow you down because the steepness overcomes the rear wheel hanging up on roots and rocks, plus the geometry is just better for control.

The bad:
1. It's just slower... loss of momentum on most trails except the very steepest ones. It is noticeable and gets in my head for regular trail riding. This is a big one as half my riding I would be better off on a full 29'r. I find myself pedaling a lot more to try and keep momentum, even on sketch downhills which can lead to pedal strikes.
2. I blow thru the battery quicker likely due to less efficiency. Anyone else see this?
3. I can't switch easily between the two wheel sizes like you can on the 2022 Rails where you can program wheel circumference using the phone app. I have to pay the dealer to change it so... Ideally I could do it myself and use the rear wheel to match the trail I plan to ride!

Overall I won't be changing back because of my short inseam and all the shorts and pants I've ruined on a 29" rear wheel, lol! The good outweighs the bad for me but I sure would like the ability to program the computer myself like on the newest Rails so I could use the wheel size based on the planned ride.

Have FUN!

G MAN