Rockrider E-st 900 changes upgrades

[DT36]

The bike doesn't go ON anymore.
When opening the case, it's full of mud, the connectors are rotten agian.
By trying to disconnect, the power connector broke, pins broken off...

Sorted now, or work in progress?

 

[BeBiker]

The motor connector is broken and rotten, maybe one day I will find that part and replace it, or remove it and solder the wires directly.

 

[silles]

maybe give this guys a call? eBike Motor Repairs & Servicing - Homepage

 

[E-MAD MALC]

Amazing this threads been going nearly four years BeBiker

 

[DT36]

Amazing this threads been going nearly four years BeBiker

Haha, just realised I bought my 900 at the start of the UK Covid lock down, March 2020.

 

[E-MAD MALC]

Four years on and the 900 is still selling
Must have got something right

 

[BeBiker]

I think the Rockrider E-st900 is commercially end-of-life.

Most of the sizes are not possible to order online,
here and there still some in stock in a shop.

And then this promo : From 2200euro to 1600euro

 

[BeBiker]

So that's what I (we) did after discovering the limitations of the D4 service.

Bought this blue M-size for the wife (also pub/spare/commute bike for me)
The black L-size is put aside for repair one day, or for parts, or...

Modifications to do will approx be the same:
* Dropper post and comfort saddle
* Mudguards
* Bike stand
* Smartphone holder
* Tools saddle bag
* Big accessoires bag for lock, keys, money, gloves,...
* 2.4 or 2.5 tyres tubeless
* Wuzei Chainring 38t
* SUNSHINE 10 Speed Cassette for Deore 11-50T
* Longer chain KMC e10 EPT10 136L and derailleur hanger

Maybe:
* Oversize front light powered from motor/battery
* Shorter 45° stem
* 203mm rotors + adapters
* SL-T8000 Shifter Multi Release

 

[silles]

I added this dropper post recently:

Tija de Sillín Telescópica Diámetro: 31,6 mm, Recorrido: 100, Longitud: 320 mm

Compra en Decathlon Tija de Sillín Telescópica Diámetro: 31,6 mm, Recorrido: 100, Longitud: 320 mm Diseñada para reemplazar la tija de sillín de la MTB

www.decathlon.es

very happy with it, no cables, so super easy to install, and very cheap for 70 euro.

probably tubeless setup next?

 

[BeBiker]

When riding alone your unwired dropper is good enough, but in group too much fast and unexpected situations come up.
I think I paid my mid-wired KS E20 +-100euro

Maybe I'll buy a Dropper+Suspension from Coast, maybe take the KS from the other bike.

COAST SUSPENSION DROPPER POST

Suspension + Drop. The Coast Post combines the benefits of a dropper with the joint saving squish of suspension. This witchcraft all happens via a dual chamber hydraulic cartridge featuring 40mm of tunable air suspension, designed to help riders on all types of bikes - from packed up trekkers...

www.pnwcomponents.eu

 

[E-MAD MALC]

When riding alone your unwired dropper is good enough, but in group too much fast and unexpected situations come up.
I think I paid my mid-wired KS E20 +-100euro

Maybe I'll buy a Dropper+Suspension from Coast, maybe take the KS from the other bike.

COAST SUSPENSION DROPPER POST

Suspension + Drop. The Coast Post combines the benefits of a dropper with the joint saving squish of suspension. This witchcraft all happens via a dual chamber hydraulic cartridge featuring 40mm of tunable air suspension, designed to help riders on all types of bikes - from packed up trekkers...

www.pnwcomponents.eu

I have that one on mine bought it two years ago still going strong

 

[Quark1980]

Hi, just found this thread after a long search online to see what others might have done with their bikes. Im happy with it for now, but there was surely room for improvement. I am by no means sporty or into heavy mountainbiking, but these bikes looked like a nice step into becoming a healthier and better person

Mods so far. More Comfy saddle. Ncx seatpost. That's about it.

Reason a started searching online was the rather limited information, so I am so happy to have found some decent info here. Not much help from decathlon here in the Netherlands about conpatible parts....

Wishlist so far.
Bigger front disk, so probably need the disk and adapter.
Bigger front sprocket. 38t might be enough, might need one bigger for use the bike for commuting mostly.

I bought 2 e-st500 for me and my wife, for some reason her front fork is nice and smooth. Mine seems "sticky" same forks.. I have no clue why.

So lastly I would like a budget airfork. Looking into the Chinese bucklos forks, they seems decent, and look Like a good upgrade, keeping in mind I don't do the extra rough stuff like jumps etc... this bike seems to be a perfect candidate for such forks. Anyone experience with those?

 

[El Grifo]

Hi, just found this thread after a long search online to see what others might have done with their bikes. Im happy with it for now, but there was surely room for improvement. I am by no means sporty or into heavy mountainbiking, but these bikes looked like a nice step into becoming a healthier and better person

Mods so far. More Comfy saddle. Ncx seatpost. That's about it.

Reason a started searching online was the rather limited information, so I am so happy to have found some decent info here. Not much help from decathlon here in the Netherlands about conpatible parts....

Wishlist so far.
Bigger front disk, so probably need the disk and adapter.
Bigger front sprocket. 38t might be enough, might need one bigger for use the bike for commuting mostly.

I bought 2 e-st500 for me and my wife, for some reason her front fork is nice and smooth. Mine seems "sticky" same forks.. I have no clue why.

So lastly I would like a budget airfork. Looking into the Chinese bucklos forks, they seems decent, and look Like a good upgrade, keeping in mind I don't do the extra rough stuff like jumps etc... this bike seems to be a perfect candidate for such forks. Anyone experience with those?

Written with AI or what ?

 

[Quark1980]

Written with AI or what ?

Why? No... why would you think this was written with ai?... weird accusation....

just looking for info about and for my bikes... and to find out if anybody tried those cheap forks to see if they are good enough for what I want... still have some sort of budget and the cost of rockshox are a bit steep for commuting...

If I want to slap a lot of money, I would better be of with a other bike altogether no? I just want to make this already decent one a bit nicer...

 

[El Grifo]

Why? No... why would you think this was written with ai?... just looking for info about and for my bikes... and to find out if anybody tried those cheap forks to see if they are good enough for what I want... still have some sort of budget and the cost of rockshox are a bit steep for commuting...

If I want to slap a lot of money, I would better be of with a other bike altogether no? I just want to make this already decent one a bit nicer...

Good that you have now changed the many spelling and syntax errors !
The first version looked liked a poorly constructed AI job.

Just sayin !

Happy conversions.

Love my EST 900

 

[Quark1980]

Good that you have now changed the many spelling and syntax errors !
The first version looked liked a poorly constructed AI job.

Just sayin !

Happy conversions.

Love my EST 900 View attachment 142987

Ah, true...

Spelling was still on dutch wich resulted I a "few" weird words .. I do tend to read what I have posted.. I am one of those guys who heavily rely on the edit-button ..

Back on topic,

My first priority is my sticky front fork.. thing is brand New, and I can compress it so I recon my pre-tension is ok.
Still the fork does not really do well with small bumps like ridges and small rock or even cobnlestone.. I have a bit of bad wrists, so I do want to get a better fork to get rid of that as much as possible. Not sure what is going on... and yes, I did check it isn't locked or something like that

 

[El Grifo]

Ah, true...

Spelling was still on dutch wich resulted I a "few" weird words .. I do tend to read what I have posted.. I am one of those guys who heavily rely on the edit-button ..

No sweat Tio. Bit of fun just !
Like I say, the EST 900 aint goin to appear on many special MTB tracks but is fine for any rough ride I have ever taken.
Great value for money and excellent specs. The new more expensive models come nowhere near !!
Clocked 2,500 k in a year mostly on the rough.
Not bad for a 73 yr old pensioner

 

[DT36]

Hi, just found this thread after a long search online to see what others might have done with their bikes. Im happy with it for now, but there was surely room for improvement. I am by no means sporty or into heavy mountainbiking, but these bikes looked like a nice step into becoming a healthier and better person

Mods so far. More Comfy saddle. Ncx seatpost. That's about it.

Reason a started searching online was the rather limited information, so I am so happy to have found some decent info here. Not much help from decathlon here in the Netherlands about conpatible parts....

Wishlist so far.
Bigger front disk, so probably need the disk and adapter.
Bigger front sprocket. 38t might be enough, might need one bigger for use the bike for commuting mostly.

I bought 2 e-st500 for me and my wife, for some reason her front fork is nice and smooth. Mine seems "sticky" same forks.. I have no clue why.

So lastly I would like a budget airfork. Looking into the Chinese bucklos forks, they seems decent, and look Like a good upgrade, keeping in mind I don't do the extra rough stuff like jumps etc... this bike seems to be a perfect 0candidate for such forks. Anyone experience with those?

Hi Buddy,
Slightly confused here. Is your bike with the fork issue a 500 or a 900?, as you say you bought 2 x 500s.
If it's a 500, have you considered the forks from a 900? These are a higher spec and I've had no problems with them on my 900. I also have a 500 in my garage, so can confirm they give a better ride.

I would recommend the front sprocket swap, as it's a big improvement. My 900 maxs out at about 28mph now on the flat.
Swapped my stem out for a suspension post and it's quite comfortable. I didn't bother with a dropper.

 

[Quark1980]

Hi Buddy,
Slightly confused here. Is your bike with the fork issue a 500 or a 900?, as you say you bought 2 x 500s.
If it's a 500, have you considered the forks from a 900? These are a higher spec and I've had no problems with them on my 900. I also have a 500 in my garage, so can confirm they give a better ride.

I would recommend the front sprocket swap, as it's a big improvement. My 900 maxs out at about 28mph now on the flat.
Swapped my stem out for a suspension post and it's quite comfortable. I didn't bother with a dropper.

Hey,

They are 500's v3 bought in 2023.. as far as I know they are quite simular.

Did you go with the 38t front sprocket?

What type of forks do the 900's use? I wasn't aware that these had different specs?
Mine 500 has a suntour xcm 120mm travel.
I would like a upgrade from it since it just doesnt feel smooth or comfortable. Any airfork sounds like a big improvement. Just don't want to shell big money out for a fork. So looking into a few Chinese brands.
Like to keep the big money in the pocket to spend on a other bike in the future when I outgrow this one in a few years.

I know balony forks are quite impopulair around the usual mtb folks. Because of lesser quality. But was thinking they might be good enough for what I want, especially in the price range they sit.
just curious if people would have some real world experience with one of those.

 

[DT36]

Hey,

They are 500's v3 bought in 2023.. as far as I know they are quite simular.

Did you go with the 38t front sprocket?

What type of forks do the 900's use? I wasn't aware that these had different specs?
Mine 500 has a suntour xcm 120mm travel.
I would like a upgrade from it since it just doesnt feel smooth or comfortable. Any airfork sounds like a big improvement. Just don't want to shell big money out for a fork. So looking into a few Chinese brands.
Like to keep the big money in the pocket to spend on a other bike in the future when I outgrow this one in a few years.

I know balony forks are quite impopulair around the usual mtb folks. Because of lesser quality. But was thinking they might be good enough for what I want, especially in the price range they sit.
just curious if people would have some real world experience with one of those. View attachment 142993

Yes, I'm sure my front sprocket on my 900 is a 38t.
Forks on the 900 are a Rockshox Judy, which state 120mm travel on them.
Plenty of them on ebay, new and used.
I would take a strong guess that these would fit your bike stem.

RockShox Judy Silver TK 29" Boost MTB Fork 51mm Offset 100mm travel | eBay

You are looking at a pair of Rockshox Judy Silver TK. From the Rockshox website Fork offset 51mm (29"). Model designator (SF) TK. Travel (mm) 100mm. Axle 15x110mm BOOST™. Lower leg type Magnesium. Wheel size 29".

www.ebay.co.uk

 

[Quark1980]

Thanks, I have heard other people mention the judy aswell as a proper upgrade. I shall take a look at those used aswell...

 

[El Grifo]

Ah ! I also thought you had a 900. Bought a 500 first but took it back and changed it for a 900 to get the better spec and 70nm motor.
38t fits straight on. Zero twiddling
Enjoy !!

 

[E-MAD MALC]

Ah ! I also thought you had a 900. Bought a 500 first but took it back and changed it for a 900 to get the better spec and 70nm motor.
38t fits straight on. Zero twiddling
Enjoy !!

Funny enough I did the same thing nearly 3 years ago, when the 900 were as rare as hens teeth, at the time
I bought the 500 and a month later the 900 came back in stock
I took the 500 to my local Decathlon shop where they had it back and credited me and I paid the extra for the 900. Sweet

 

[El Grifo]

Funny enough I did the same thing nearly 3 years ago, when the 900 were as rare as hens teeth, at the time
I bought the 500 and a month later the 900 came back in stock
I took the 500 to my local Decathlon shop where they had it back and credited me and I paid the extra for the 900. Sweet

 

[El Grifo]

Viva Decathalin !
Dem is da Bollocks maaan

 

[Quark1980]

So... I did a thing...

I just ordered a Chinese fork after a lot a reviews and searching what I could expect. I know this could be a waste of money, but since i got a few coupons I couldn't resist my curiosity and went thought with it for 90 euros..

Since people only seem to complain after real abuse, I reckon I could be fine since I only do some tarmac and now and then some gravel or sand routes.

I will update my findings if it arrives

At least my curiosity will be statisfied, and will always have the original fork as a backup.... if all fails, I will probably end up going for a judy... but hey.. this seems to be a fun adventure

 

[E-MAD MALC]

So... I did a thing...

I just ordered a Chinese fork after a lot a reviews and searching what I could expect. I know this could be a waste of money, but since i got a few coupons I couldn't resist my curiosity and went thought with it for 90 euros..

Since people only seem to complain after real abuse, I reckon I could be fine since I only do some tarmac and now and then some gravel or sand routes.

I will update my findings if it arrives View attachment 143022

At least my curiosity will be statisfied, and will always have the original fork as a backup.... if all fails, I will probably end up going for a judy... but hey.. this seems to be a fun adventure

Well it's not what you would call braking the bank to give them a shot
I would say just keep us updated on the setup and performance never know might start a new trend

 

[silles]

cheap Chinese forks are a death trap. be careful

My gf has the e510 with Rockshox xc30, mine is a 900 with Rockshox judy air.

Judy is so much better.

have u consider a lower leg service? When I did it on the xc30 it was actually missing the foams, and stanchions were bone dry

 

[El Grifo]

cheap Chinese forks are a death trap. be careful

My gf has the e510 with Rockshox xc30, mine is a 900 with Rockshox judy air.

Judy is so much better.

have u consider a lower leg service? When I did it on the xc30 it was actually missing the foams, and stanchions were bone dry

Did not want to appear rude, but the above vid is exactly what I would have expected.
Bunch of garbage by all accounts.
Surely your current rockshocks are a better choice for your type of riding .
Much safer and thats for sure !

 

[Quark1980]

Lower leg service would be bad with a new bike... so i doibt anthing is worn...

and yes, I found this video aswell, amongst others... however, stil am curious about the actual quality, and see this as a experiment. The suntour forks that came with the bike are just eh... cheap from a technical point of view just a spring in a tube... kinda crude... they might be stronger yes.. agreed. I do want to keep you guys updated about my findings.

I do agree that they simply cannot be the same quality as a technical simular build fork... Chinese airfork vs suntour airfork. That's why I went a "class" up in intended use so to speak... it's a Chinese "pro" version
In my book that means, sturdy enough for normal day tot day use... hopefully I am right... on the other hand, I know from experience that in some cases the branding will be the mail reason things are expensive. My coworker was in the business importing bikes and parts on a big scale for bigger brands in europe. According to him a lot of the cheap knockoff brands actual Come from the same factors as shimano for example, the reason they are cheaper is mostly the fact that the cheap stuff dienst have to be as light as the pro stuff. In fact he told me sometimes off-brand stuf -can- be more sturdy in some cases...

During this experiment, I want to strip the suntour fork and service that one and hopefully find out why the thing is sticky..