Rail (750Wh) It’s a great bike, but ultimately it’s flawed in one critical aspect

[Dave_B]

It’s fair to say I’ve had a few issues with my bike, all electrical related, but they do appear to be fixed now.

Since buying it I’ve added a coil shock, upgraded the Zeb with the new debonair+ spring, mulleted (high chip) and 155mm cranks.

I have also added the battery anti rattle bracket.

The bike is now a lot quieter than when I bought it.

Today was my first really long ride on rough rocky trails. I went to Afan and did about 29 miles, 3000ft of climbing, all in either eMTB or Tour+ and had 25% battery remaining.

The good things…

The bike rides extremely well, really happy with how it handles on both up and down and it supremely capable.

It climbs like a goat, eMTB mode is simply amazing and definitely the best motor I’ve ridden (previous has been Shimano and the latest Brose).

The battery performance is equally as good, I have zero range anxiety with this bike.

It rides great as a mullet. Prefer it to full 29r. The flip chip in high and the 155mm
Cranks works really well with minimal pedal strikes (and the ones I did have were mainly my fault).

The bad, and the thing that I don’t think I’ll ever get used to, the motor rattle. Sounds like a bag of bolts. The battery no longer rattles, but the bike still sounds cheap when riding over rough trails. I was aware of this trait in the motor when I bought the bike, but I just find it very off putting and it detracts from the ride.

 

[Roy D]

removing the battery lock made it much quieter. But you’re right I don’t think I can get the motor rattle to stop bothering me. It’s all that’s left on what would be a great bike. I’m waiting for the next gen rail. Hoping for a TQ motor.

 

[Dave_B]

Same. Fingers crossed.

 

[slomtbr]

Once I learned the cause of the noise, it stopped bothering me.
If it meant something was wrong, that would be very different.

 

[Dave_B]

That’s my current mentality with it, but I find it detracts from the ride experience.

I’ve got no option but to keep the bike so I’m going to have to get used to it.

 

[#lazy]

Once I learned the cause of the noise, it stopped bothering me.
If it meant something was wrong, that would be very different.

?????

 

[steve_sordy]

?????

I understand what he means.

 

[Dave_B]

Yeah. Quite simple.

The noise is supposed to be there, so all good, I can relax about it.

As opposed to, there should not be a rattle, what the feck is it and how do I stop it, it’s driving me bonkers !

 

[RustyMTB]

Spent two hours truing a brake disc yesterday, irritating noises are not lost on me. However... I find it helps to keep in mind the bike & the brake disc are the product of two different groups of people. My bike is awesome, the guy who stamps brake discs at Shimano maybe not so much. Dunno, maybe this comes across as a petty point but it works in my head & I run the same motor as you.

 

[Dave_B]

The Trek Rail is an awesome bike.
The Bosch motor is very good, but it annoys me.



I would happily have motor drag in favour of the rattle.

 

[RustyMTB]

Unlucky!

 

[Mikerb]

I have 3 Bosch motored bikes..........none of them rattle that I can hear above he general trail noise. One is a hardtail, the other 2 are Whytes. In my opinion, yes the rattle comes from the meshed gears of the motor but it is caused by how much the combination of the rear triangle design and shock set up causes pedal slap. There is little or no such feedback to the chainwheel on a hardtail. Both Whytes have rear shocks tuned specifically by Whyte with the main characterisitics being a soft but progressive tune. Maybe playing with ( or getting a specialist to soften the tune) the shock settings will help you with the rattle?? It is also possible the more linear action of a coil shock makes the rattle worse?

 

[Doomanic]

If you jam a pencil in each ear it stops the motor rattling...

 

[Zimmerframe]

If you jam a pencil in each ear it stops the motor rattling...

Well that's really helpful isn't it !

Like an 8B a 2B an F ... just dribble out your secret solutions ....

 

[Dave_B]

I have 3 Bosch motored bikes..........none of them rattle that I can hear above he general trail noise. One is a hardtail, the other 2 are Whytes. In my opinion, yes the rattle comes from the meshed gears of the motor but it is caused by how much the combination of the rear triangle design and shock set up causes pedal slap. There is little or no such feedback to the chainwheel on a hardtail. Both Whytes have rear shocks tuned specifically by Whyte with the main characterisitics being a soft but progressive tune. Maybe playing with ( or getting a specialist to soften the tune) the shock settings will help you with the rattle?? It is also possible the more linear action of a coil shock makes the rattle worse?

Valid point that. I’m on a 571 lb spring, I could easily try a slightly softer one.

 

[Zimmerframe]

I have to say, that whilst it's disconcerting to hear a rattle when you ride, my subconscious generally filters it out now. Plus I normally run finned XT pads which rattle like the Eiffel tower falling down in a storm - this helps as in the end you have no idea where the rattle is coming from. Eventually, you don't care because by then, nothing matters .. Then you quit your job, your marriage, house and just ride the rattle ...

 

[irie]

My '22 alloy Rail motor did not rattle before, nor did it rattle after, installing an Ohlins TTX22m.2 coil shock. Or at least I don't hear it. 85kg ready to ride with a 525lb spring

ps neither do I have a pencil jammed in each ear.

Edit: 525

 

[Planemo]

I have 3 Bosch motored bikes..........none of them rattle that I can hear above he general trail noise. One is a hardtail, the other 2 are Whytes. In my opinion, yes the rattle comes from the meshed gears of the motor but it is caused by how much the combination of the rear triangle design and shock set up causes pedal slap. There is little or no such feedback to the chainwheel on a hardtail. Both Whytes have rear shocks tuned specifically by Whyte with the main characterisitics being a soft but progressive tune. Maybe playing with ( or getting a specialist to soften the tune) the shock settings will help you with the rattle?? It is also possible the more linear action of a coil shock makes the rattle worse?

Fair shout that, I had never thought about some bikes maybe having a high pedal kickback due to the rear sus design, and given the Bosch rattle is very much dependant on quick changes in rotation of the chainring it makes sense that some bikes will deffo be louder than others. Like you, I don't notice mine being obtrusive on any ride and I certainly can't hear it at all on anything approaching a fair downhill gravel track what with all the tyre noise.

 

[Wilbur]

I feel your pain Dave_B; my '21 Rail 7 motor with 1300km on it is very rattily, but my mates new '22 9.8 is almost quiet by comparison. Some motors seem worse than others.
I doubt any shock tune would reduce mine; it's consistently there on any bumps. I can reproduce the rattle simply by slight back/forward pedal motion when coasting. I feel like taking it apart and putting some grease on the cogs.

 

[Dave_B]

There does seem to be some debate on whether it not a coil is the correct choice for the Rail. Reading some posts, it has an 18% leverage ratio (?) so there is debate around linear or progressive springs.

I’m 85kg and TFtuned fitted at 571 linear spring. The Cane Creek progressive spring fits the Ohlins, so I could try a 500 to 610 progressive.

Maybe worth a try for only £70

The next rate down for linear Ohlins is 548 and 529 so about a 4% and 8% reduction respectively.

The rear end of the bike already feels great, I am by no means a big hitter, I’m
not bottoming out the shock, so maybe slightly softer will work for me?

 

[Doomanic]

If your sag is correct with the 571 a 500-610 will be too soft.

 

[irie]

There does seem to be some debate on whether it not a coil is the correct choice for the Rail. Reading some posts, it has an 18% leverage ratio (?) so there is debate around linear or progressive springs.

I’m 85kg and TFtuned fitted at 571 linear spring. The Cane Creek progressive spring fits the Ohlins, so I could try a 500 to 610 progressive.

Maybe worth a try for only £70

The next rate down for linear Ohlins is 548 and 529 so about a 4% and 8% reduction respectively.

The rear end of the bike already feels great, I am by no means a big hitter, I’m
not bottoming out the shock, so maybe slightly softer will work for me?

Why would a progressive and/or softer spring significantly reduce "motor rattle"?

BTW I'm 85kg with winter gear and a 525 spring gives me 28% sag ...

 

[Dave_B]

I’m assuming a more compliant ‘plush’ ride will stop any stuttering at the back end and smooth things out even more and potentially reduce rattle dynamics. ?

 

[torabora851]

Seems like the guys fix rattling for Shimano by adding some rubber boot to a crank, wondering if we can do something similar?

I fixed the Ep8 motor rattle

When I added xt cranks to my rise i left on the e13 chain ring and rubber boot/ring. The rubber ring touches the inside of the crank and creates slight friction if you backpedal. Without the ring (or with e13 cranks) when you go over rough ground there is a small amount of play as the crank...

www.emtbforums.com

 

[Rob Rides EMTB]

There does seem to be some debate on whether it not a coil is the correct choice for the Rail. Reading some posts, it has an 18% leverage ratio (?) so there is debate around linear or progressive springs.

I’m 85kg and TFtuned fitted at 571 linear spring. The Cane Creek progressive spring fits the Ohlins, so I could try a 500 to 610 progressive.

Maybe worth a try for only £70

The next rate down for linear Ohlins is 548 and 529 so about a 4% and 8% reduction respectively.

The rear end of the bike already feels great, I am by no means a big hitter, I’m
not bottoming out the shock, so maybe slightly softer will work for me?

Trek Rail 9.9 2022 has a moderately progressive suspension curve. Considering the amplitude and the shape of the leverage ratio curve, the final progressivity is 30%, meaning that it takes more 30% force to bottom-out comparing to any fully linear bike equipped with the same shock and SAG%

from the analysis here

 

[Dave_B]

Thanks @Rob Rides EMTB
Out of interest, what spring weight do you use?

And again out of interest, do you ride yours anymore now you have the Pole ?

 

[Rob Rides EMTB]

Thanks @Rob Rides EMTB
Out of interest, what spring weight do you use?

And again out of interest, do you ride yours anymore now you have the Pole ?

Think its a 500lb iirc

Agree on Bosch rattle, its the one annoyong thing. Motor is so much better than the Brose though, everywhere else.

On my Kenevo I notice how silent it is, every time I ride it, having both the Rail and Kenevo at the moment as personal bikes. ALL Bosch motors rattle on every bike I have ridden, and ALL Brose motors are blissfully silent on the descent!

BUT, the way the Bosch picks up instantly, the torque, feel and characterists, blow the Brose away. The Bosch is far superior...

 

[Rob Rides EMTB]

And again out of interest, do you ride yours anymore now you have the Pole ?

No!

 

[Dave_B]

I agree with you. the Rail climbs like a goat.

 

[Dave_B]

I did 48km with 936m of climbing, all in eMTB or Tour+ and still had 25% battery left.
climbing up Afan was a breeze in eMTB mode.