The Universal Gates Belt MTB conversion Kit thread (By Sidepod)

Sidepod

Active member
Sep 2, 2020
584
395
Oxford
Moderator : On converting an EMTB to Rohloff :

Good luck with that. I’ve tried. They won’t sell you one unless it’s through a bike shop who will assess your bike, carry out various measurements with their test kit and then take responsibility for it.

In addition it’s tricky to find a chainring for the belt drive unless you have Bosch.
(I see little point in converting unless I can go the whole way and include belt drive)
 
Last edited by a moderator:

paulmoir

Well-known member
Apr 8, 2019
58
153
Gold Coast, Qld Australia
Good luck with that. I’ve tried. They won’t sell you one unless it’s through a bike shop who will assess your bike, carry out various measurements with their test kit and then take responsibility for it.

In addition it’s tricky to find a chainring for the belt drive unless you have Bosch.
(I see little point in converting unless I can go the whole way and include belt drive)
You cannot use a Gates belt with a full suspension bike, unless it is a specially designed tensioner (not anything off the shelf, you can buy). Belt tension is critical and todate only a couple of brands have made a Rohloff Gates belt drive full suspension mtb (eg. Nicolai EBOXX E14).
 

Sidepod

Active member
Sep 2, 2020
584
395
Oxford
Why can’t I fit a belt to a full suspension bike? Obviously a tensioner is required just as you say, like the Nicolai.
 

Gary

Old Tartan Bollocks
Author
Subscriber
Mar 29, 2018
10,496
10,702
the internet
Simply put. Most FS bikes have too much chaingrowth for an added tensioner to keep the belt properly tensioned.
In order for a belt drive to stay properly tensioned throughout the suspension travel on most FS bikes the tensioner and pulley placement would ideally have been designed with the frame.
consistent belt tension is far more important than chain tension on a traditional chain driven drivetrain
 
Last edited:

Sidepod

Active member
Sep 2, 2020
584
395
Oxford
I fully understand suspension kinematics.
Correct/sufficient tension is simply a function of tensioner design. We’re not splitting the atom here.
 

Zimmerframe

MUPPET
Subscriber
Jun 12, 2019
14,020
20,787
Brittany, France
I fully understand suspension kinematics.
You would seem to have answered most of your own question then ?

We’re not splitting the atom here.
No, but you'll probably splitting all those lovely little belt teeth from the belt or just snapping the belt/massively reducing it's life span.

Just look at the amount of moving around a chain does even with a perfect derailleur setup when you're hammering it on the rough stuff - that's not even taking into account adding suspension movement into the equation.

Keeping that tension optimum in the conditions it would be used in would be virtually impossible unless you designed the bike around that drive train, even then it would be a far more complicated system to keep the belt where it needs to be.

We know from previous threads that you have your idea of what a perfect bike is for YOU and in your view every bike on the planet should be built to conform around that ideology - but for many people that fire road cruiser is not the bike they want because it just won't work for how they ride.

I'm not trying to be difficult and pee on your bonfire, but for someone who says they understand so much you make some outlandish simplifications ?

Anyway, if you were trying to split an atom, you wouldn't use a belt. :)
 

paulmoir

Well-known member
Apr 8, 2019
58
153
Gold Coast, Qld Australia
Why can’t I fit a belt to a full suspension bike? Obviously a tensioner is required just as you say, like the Nicolai.
Belt tension is critical and much higher for a Gates belt drive to operate properly and reliably, completely different than chain tension. Both Nicolai and Zerode have designed a bike with a tensioner which maintains a constant high belt tension throughout the suspension travel. As long as you can have a tensioner designed and manufactured to do the same, yes you can fit it to a full suspension bike. But that’s why there’s only a couple of belt drivetrain fs bikes right now… as this is a “specially designed” tensioner.
 

Sidepod

Active member
Sep 2, 2020
584
395
Oxford
“As long as you can have a tensioner designed and manufactured to do the same, yes you can fit it to a full suspension bike”

Exactly.
 

paulmoir

Well-known member
Apr 8, 2019
58
153
Gold Coast, Qld Australia
“As long as you can have a tensioner designed and manufactured to do the same, yes you can fit it to a full suspension bike”

Exactly.
But you cannot fit an off-the-shelf tensioner. You must design and manufacture a custom tensioning device/assembly for that frame you want to convert to a Gates belt. And that’s why there are only two bike manufacturers in the world today that have done this… it is part of their integrated frame design.

Which is “exactly” what I said yesterday… “You cannot use a Gates belt with a full suspension bike, unless it is a specially designed tensioner (not anything off the shelf, you can buy)”
 
Last edited:

Sidepod

Active member
Sep 2, 2020
584
395
Oxford
He must have gained a lot of knowledge since last july, when he said (in the R&M Rohloff discussion) "I’d love to retrofit one of these units but I can’t see a way to do it. "
I can’t, not on my current motor/chainring. It will need a new centre section machining to accept the motor output shaft.
Also there is not enough offset of the chainweel from the frame surrounding the motor housing to allow for the belt width.
This is why it’s much east with a Bosch motor unit.

Is that enough for you?
 

Sidepod

Active member
Sep 2, 2020
584
395
Oxford
My current bike/motor is the Haibike Flyon.

There are off the shelf belt drive wheels for Bosch crank/spider unit on the Gates website which would be perfect.

To use one of those I’ll need to machine an adapter to fit my cranks:motor output shaft. Plus as stated, I will also need to space the wheel out away from the frame housing for the motor to allow for belt width. This may not end up with the alignment correct for the hub.

All doable but probably easier with a Bosch unit.
 

Gary

Old Tartan Bollocks
Author
Subscriber
Mar 29, 2018
10,496
10,702
the internet
Why do you even want a belt drive on your Emtb?
Because of the tension required they pretty much muller Freehubs/freewheels on a lot of normal rigid commuter bikes. Personally I wouldn't want one anywhere near any mtb of mine. Let alone an FS Emtb.
 

Zimmerframe

MUPPET
Subscriber
Jun 12, 2019
14,020
20,787
Brittany, France
@Sidepod

Lets give you the benefit of the doubt and believe you are the genius you think yourself to be ..

You understand Suspension Kinematics. You say you have the design/manufacturing capability to take care of it.

You can't do it on your bike because of fluffy excuses. Cool, no worries.

Just show us the design of your Universal Full suspension MTB Belt tensioner. You don't need a bike for that and it's universal anyway to allow conversions.
 

Sidepod

Active member
Sep 2, 2020
584
395
Oxford
“Lets give you the benefit of the doubt and believe you are the genius you think yourself to be .”

Lovely Zim. You must be so proud of yourself.
 

dobbyhasfriends

🌹Old Bloke 🎸
Subscriber
Sep 19, 2019
3,256
4,643
Llandovery, Wales
handbags.jpg
 

CjP

PRIME TIME
Subscriber
Jan 1, 2019
1,671
2,394
Everywhere
To make a tensioner work with your bike, you will need to hack into it. That’s if there is even any room for it. Then there’s the alignment issues.
I racked my brain for days trying to make this work.
In the end it will be easier and cheaper to buy a Nicolai or Muller.
Why do you have such a hard on for Gates belts? Or are you like me that gets an idea in your head and can’t let it go?
 
Last edited:

Gary

Old Tartan Bollocks
Author
Subscriber
Mar 29, 2018
10,496
10,702
the internet
World peace bro.

The knock on effect from making a middle aged nerd happy for a few days or so until the novelty wears off and they start lusting after some other unique trinket to fit to their hobby horse is bigger than you imagine.
 

Waynemarlow

E*POWAH Master
Dec 6, 2019
1,107
888
Bucks
I say it with zero fuck's given
So if a middle aged nerd ( I guess a great deal of your clients are such ) came into the shop and requested you fitted a belt drive system that would earn you a tidy sum, I would guess you would decline :cool:
 

Gary

Old Tartan Bollocks
Author
Subscriber
Mar 29, 2018
10,496
10,702
the internet
I don't have clients or a shop Wayne and the last time I looked I am myself also a middle aged bike nerd.

Fitting a belt drive drivetrain isn't in the slightest difficult but if someone clueless enough to ask me to fit one to their standard Ebike came into my life I'd kindly repeat the same information I've already given here and bid them a good day.
 

Zimmerframe

MUPPET
Subscriber
Jun 12, 2019
14,020
20,787
Brittany, France
“Lets give you the benefit of the doubt and believe you are the genius you think yourself to be .”

Lovely Zim. You must be so proud of yourself.

I thought it was quite complimentary considering the circumstances ????

If you don't understand why, lets re-cap :

I see little point in converting unless I can go the whole way and include belt drive

It’s tricky to find a chainring for the belt drive unless you have Bosch.

I fully understand suspension kinematics.
Correct/sufficient tension is simply a function of tensioner design. We’re not splitting the atom here.

I have the design/manufacturing capability to take care of that.

There are off the shelf belt drive wheels for Bosch crank/spider unit on the Gates website which would be perfect.

To use one of those I’ll need to machine an adapter to fit my cranks:motor output shaft.

All doable but probably easier with a Bosch unit.

There seem to be two sides to this opinion.

Yours, that it's easy, there's no reason why it's not available off the shelf and that doesn't matter anyway as you can buy the parts, modify things and you clearly have the abilities and facilities to do all of that so you could do it yourself. The only reason you wouldn't convert to a rohloff is if you couldn't have the belt and you're obviously capable of making that a possibility.

The other side of the opinion is that it's really really difficult to achieve in reality and ideally needs the frame and kinematics to be designed with the belt drive in mind from the outset.

In conclusion :

Stop typing and do it, otherwise you're just using the forum to inflate your own ego and wasting everyones time.

Hence why I thought my comment was quite complimentary. It was only taking your point of view and embellishing it ?
 

EMTB Forums

Since 2018

The World's largest electric mountain bike community.

554K
Messages
27,999
Members
Join Our Community

Latest articles


Top