Stealth FUTR owners builds and pics

[Kepler]

I have been though the same issue over many years of riding. I have always liked to pedal even on high powered bikes at high speed where my input is doing F-All but also have the ability to pedal home if needed. Tried lots of combos but i think I have come up a solid economical solution on my Beta 29'er build.

Setup is as follows.
Mxus 2 motor with a dnp 8 speed 11-34
Entry level Shimano Altus 8 speed derailleur and matching rapid fire shifter

Chainring end:
130mm BCD spider with dual chainrings.

Large chainring is a 54 tooth but has a narrow / wide tooth pattern. This is the key to keeping the chain on under rough conditions.

Small chainring is 39 tooth standard chainring and is my "get me home" chainring if I need to pedal home. No front derailleur. I just manually put the chain on the small chainring if ever needed. So far, I have never need to do this so its only going to be a rare situation to use the small chainring.

Custom chain keeper mounted on the swingarm shock mount that wraps over the front of the chain only and acts as last line of defence. A large diameter chain guard would do the same job but its hard to find one that suites a 54 tooth chainring.

I could have used a schlumpf and had one ready to go however I opted for the large chainring because it gives me better chain to swing arm clearance and reduces chain slap considerably.

Other items of note is that the 8 speed dnp is screwed flush onto the motor housing so I could squeeze it all on on a 135mm dropout. Even then I needed to spring the swingarm out by an extra 5mm to fit it all in. It also means I can't shift to the largest gear on the rear but i can live with 7 usable speeds.

This combo allows me to pedal comfortably right through the bike's speed range up to 60kph and will get me home unassisted if needed.

 

[Cowardlyduck]

Thanks for the input Kepler. Some great idea's there for sure.

I've already gone down the BCD110 route with my spider and chain ring (which I think is either 54 or 56T from memory), and all my other bikes run BCD110, so I don't think I will change that now.

The custom chain keeper mounted on the swingarm shock mount sounds interesting. Can you post a picture of this and details on how you made it?
Your right about chain ring guards being hard to find, but they are out there. From memory I sourced one from the US to fit the inside of my Schlumpf on my Fighter. Before that the chain would drop off all the time over rough terrain. Sometimes they are impossible to find though, like when I tried to find one to fit the 60T BCD110 I used on my Recumbent commuter...which I've since replaced with a Schlumpf.

Do you just mount the rapid fire shifter on the RHS, or do you flip it upside down to work on the left? Got a photo?
One of the reasons I've alway's gone with grip shifters is I don't like having the shifter on the RHS, and the only LHS 7 speed rapid fire type shifters I've found are quite $$$.

Cheers

 

[Kepler]

BCD130 or BCD110 doesnt really matter, its the narrow / wide tooth pattern that makes all the difference to keeping the chain on.

Chain keeper is easy to make. I just used a block of HMWPE machining plastic. I get it from here. http://www.profileplastics.com.au/ I just raid their off cuts bin but you can get pieces cut and sent. You can even draw soming up and they will machine it for you. I have a mill but you could easily make it using basic hand tools.







With regards to handlebar layout. I prefer rapid fire shifters and have stuck with a righthand standard mounting position. I have my throttle on the left. I use an inverted thumb throttle that you now push away from from the top to accelerate. Bit weird I know but I find it really easy to use and fits in nicely with the the rest of the stuff on the bars.
(edit) To be clear, small red lever on the LHS is the seat post dropper. The throttle is far left. If you look closely, you can see it is inverted with the lever at the top.

 

[PRW]

I use an inverted thumb throttle that you now push away from from the top to accelerate. Bit weird I know but I find it really easy to use and fits in nicely with the the rest of the stuff on the bars.

Very nice idea Kepler, hadn't thought of that! I far prefer rapidfire to twist shifters, but the throttle is always an issue - so your method is very clever.

What is on your side panels - carbon strips?

 

[Kepler]

Thanks PRW. The carbon strips are just stick on vinyl, the same stuff Stealth uses. Wanted to do something a little bit different. Needed to break up the look of the gloss side covers on the matt black frame so went with the red anodised fasteners and the carbon strips.

You can also see the small black screws that hold the internal 18 FET controller in place with the side cover now used as the controller's main heatsink. This was why I didn't go down the path of cutting out lattis like Hyena and Allex did which I really like also.

 

[PRW]

You can also see the small black screws that hold the internal 18 FET controller in place with the side cover now used as the controller's main heatsink. This was why I didn't go down the path of cutting out lattis like Hyena and Allex did which I really like also.

ha! Again very clever!

 

[Kepler]

Some better shots of the throttle and shifters. Posted this about 10 pages back but I know it easily gets missed or lost in the clutter.

View attachment 1

If you are wondering what the microswitch is for, it activates the regen. I only ever use the front brake with this setup. The free stroke on the front lever activates the regen, then I pull in front brake if I need it. Most of the time all stopping is via the regen except for the last little bit.

 

[Rix]

I have been though the same issue over many years of riding. I have always liked to pedal even on high powered bikes at high speed where my input is doing F-All but also have the ability to pedal home if needed. Tried lots of combos but i think I have come up a solid economical solution on my Beta 29'er build.


Large chainring is a 54 tooth but has a narrow / wide tooth pattern. This is the key to keeping the chain on under rough conditions.

Small chainring is 39 tooth standard chainring and is my "get me home" chainring if I need to pedal home. No front derailleur. I just manually put the chain on the small chainring if ever needed. So far, I have never need to do this so its only going to be a rare situation to use the small chainring.



This combo allows me to pedal comfortably right through the bike's speed range up to 60kph and will get me home unassisted if needed.

I am running a similiar 2 chain ring set up on my Beta. 36T/54T. The difference is I am running a 16T freewheel on the rear. With the Paul Melvin tensioner, I can run 2 chainrings up front with a maximum difference of 20T. Kind of a poormans Schlumpf.....Almost.

 

[Kepler]

Kind of a poormans Schlumpf.....Almost.

Smartmans Schlumpf in my opinion. Really, how often do you need to use the small chainring? Just nice to have it there to get you home.

 

[Rix]

Kind of a poormans Schlumpf.....Almost.

Smartmans Schlumpf in my opinion. Really, how often do you need to use the small chainring? Just nice to have it there to get you home.

thanks John, Yah, the small gear only gets used on the steepest of slow climbs....and if the battery were to go dead.

 

[PRW]

Some better shots of the throttle and shifters. Posted this about 10 pages back but I know it easily gets missed or lost in the clutter.

View attachment 1

If you are wondering what the microswitch is for, it activates the regen. I only ever use the front brake with this setup. The free stroke on the front lever activates the regen, then I pull in front brake if I need it. Most of the time all stopping is via the regen except for the last little bit.

that microswitch is just way too advanced for me... great setup, though!

 

[PRW]

I am running a similiar 2 chain ring set up on my Beta. 36T/54T. The difference is I am running a 16T freewheel on the rear. With the Paul Melvin tensioner, I can run 2 chainrings up front with a maximum difference of 20T. Kind of a poormans Schlumpf.....Almost.

nice to see what fits on the Beta! Great ideas here, thanks guys... my wife doesn't like schlumpfs with the whole heel clicking thing (she is half German ), I need to make a plan for her Beta

 

[IanM]

Kepler your beta is a beautiful and well thought out build thanks for posting the details of your setup. Some valuable info there. I really want to try out the regen switch on the front brake lever but my controller will need replacing its never had functional regen.

Kind of a poormans Schlumpf.....Almost.

Smartmans Schlumpf in my opinion. Really, how often do you need to use the small chainring? Just nice to have it there to get you home.

+1 that's a cool solution you have there Rix, I'm loving all these great ideas coming from you guys.

 

[Swe]

Custom chain keeper mounted on the swingarm shock mount that wraps over the front of the chain only and acts as last line of defence. A large diameter chain guard would do the same job but its hard to find one that suites a 54 tooth chainring.

I could have used a schlumpf and had one ready to go however I opted for the large chainring because it gives me better chain to swing arm clearance and reduces chain slap considerably.

Is it "normal" to drop the chain? Only on heavy dirt road or also in really high speed on flat ground if a bump appears? What will happen if you drop it in the front and going high speed?

I have a 7 speed on my Beta, think I only have a normal chain ring in front. I was thinking if I should fix anything better only if I am getting problems in future, or if it could be really dangerous and that I should fix it right away.

Have never got problems on my MTB but the Beta is my first full suspension bike.

 

[Cowardlyduck]

For these bikes (Beta/Alpha) it's not really dangerous, just a pain having to stop and put the chain back on.

That being said, on other bikes it can be dangerous. I had the chain come right off the front chain ring on my recumbent once, right as I made a right hand turn, which resulted in the chain getting sucked up and around the rear wheel until it slammed into the rear rim brakes locking the rear up at 50kph. I fishtailed down to about 20kph before it threw me off causing a decent amount of damage to both me and the bike.

So yeah, mainly it depends on the length and position of the chain. For these FS MTB style bike's it not normally dangerous, just annoying.

Cheers

 

[Kepler]

Custom chain keeper mounted on the swingarm shock mount that wraps over the front of the chain only and acts as last line of defence. A large diameter chain guard would do the same job but its hard to find one that suites a 54 tooth chainring.

I could have used a schlumpf and had one ready to go however I opted for the large chainring because it gives me better chain to swing arm clearance and reduces chain slap considerably.

Is it "normal" to drop the chain? Only on heavy dirt road or also in really high speed on flat ground if a bump appears? What will happen if you drop it in the front and going high speed?

I have a 7 speed on my Beta, think I only have a normal chain ring in front. I was thinking if I should fix anything better only if I am getting problems in future, or if it could be really dangerous and that I should fix it right away.

Have never got problems on my MTB but the Beta is my first full suspension bike.

I am tipping you have a front derailleur on your MTB which stops most chain drop issues. We don't have anything on our ebikes with a standard setup so we need to come up with other solutions.

You will see that most high new high end MTB's have a single front chainring these days and a 12 speed cassette that goes right up to a 44 tooth gear on the back. To keep the chain on under all conditions they use a combo of clutched derailleur and a single Narrow Wide chainring. You need to go a minimum 10 speed cassette to find a clutched derailleur so the next best thing if you are using a standard derailleur is to go with the combo I have described above.

If you are not using a derailleur, I think Rix's solution is ideal.

 

[Lash]

Bravo Lash! you jump very well with your ebike! and your landings are smooth and nice, it seems you control your body! I've never tried something similar.
I've watched your battery build video 2-3 times, are you happy with the results ? how many km can you do with this riding style ?

Hey. Thanks. Yeah starting to get the hang of jumping with a heavy hub. It's ugly when you get the rear tipping you forward.

Yeah I'm happy with my battery build i get about 60km out of it with a mixed riding style.

Having said that I'm about to unwrap it and attend to a parallel group that has drifted too low for bulk charging using the adaptor. So that is annoying but it's my fault as i didn't know about balancing for a year.

Expect a video on that soon. Hopefully there is no faulty cells causing the problem.

All good learning.

I reckon single speed is all you need 99% of the time too.


Sent from my SUPER using Tapatalk

 

[Swe]

Okay sounds good that it should not be dangerous if chain jumps. I will ride more and see how it goes. I actually made a misstake when buying the derailleur and that stuff so will think of this when I upgrade.

Don't know why I talked about full suspension as if it was important. I was thinking the chain would get more loose with suspension on Beta but I was thinking wrong...

 

[Rix]

If you are not using a derailleur, I think Rix's solution is ideal.

It works surprisingly well. If I was to modify the gear ratio, I would go with a 38/54T with a 16T on the rear. 38/16T is perfect for offroad climbing assist. With this ratio, the Beta with the MAC 10 geared hubbie can be pedal assisted on climbs so steep one will loose traction before running out of power. With 16/36T runs out of traction with ease climbing steep stuff. The 16/54T is perfect for pedal assisting on the road up to 25MPH without having to high of a pedal cadence.

 

[IanM]

So just to confirm that a dnp 7spd freewheel and mxus 3k v2 does fit on the alpha. There was a bit of mucking around involved but I think it should be worth it.
So first I had to make a short steel sleeve spacer as the axle shoulder was inside the freewheel. I then needed to widen the dropout width from 150mm to 155mm which I achieved by using a small jack to carefully spread the ends of the swingarm out.
On my mxus where the freewheel thread is, there is a raised section which is part of the sidecover, this makes the freewheel sit out leaving a gap of 10mm or so between the sidecover and first cog. If I would've gone to the effort of machining that part down flush with the sidecover , the 150mm dropout would've been enough. I took the easiest option to widen the dropouts.
Now my rim was off centre so dishing of the wheel was necessary, I needed to re lace a new rim on any way as the old one was very wobbly from hitting logs and rocks at high speed. Next up on the to do list, install derailleur and shifter and some sort of chain guide. I think for the chain guide I will do something similar to what Kepler did on his beta (but not nearly as pretty )
If I am happy with this setup then I will upgrade the derailleur and cranks etc.

 

[Rix]

Hi Ian, based on the pics angle and your dishing of the rim, all but your smaller 3 sprockets on the cluster will be unusable as the chain line will cross with the tire you mount on the rim. Thats just based on the pics though. Have you checked your chain line yet?

 

[IanM]

Hi Ian, based on the pics angle and your dishing of the rim, all but your smaller 3 sprockets on the cluster will be unusable as the chain line will cross with the tire you mount on the rim. Thats just based on the pics though. Have you checked your chain line yet?

Hey Rix, I should find out today if I have chain line issues once I get a tire on there. Hopefully it won't be too bad, if it's going to limit the gear range that much then I might have to try something more like your setup. I like the fact that the dnp has an 11 tooth sprocket so it will likely be staying on there. A new crankset with 36/54 similar to yours would be the option to try next.

 

[Cowardlyduck]

Thanks for the update Ian.

This makes me think it would be easier to do as AW suggested and pull apart the freewheel to reduce the cogs by one or 2. It seemed like you just need 2 chain whips to make it work. Few of us actually need/use all 7 speeds...we all just want that 11T and some of the easy gears to get home with a flat battery.

I reckon if someone started pulling apart and reselling DNP's as 5 or 6 speed with the 11T cog, they would be very popular around here.

Cheers

 

[Hyena]

Re: rebuilding freewheels, unlike splined cassette types the thread on ones have a few steps i the body where the different cogs slip on, so you can't create a mega-range type 3 speed - which would otherwise be excellent!
I dont have one in front of me but from memory there's 3 different steps in the FW body for a 6 speed and then the 7th is often doubles as the screw on lock ring. Chainline issues aside for the larger gears I've found it's the smallest gear you sometimes can't use because it's hard up against the swing arm and there's no room for the chain - unless you get creative with spacers and spread the dropouts a few mm.

edit: googled a photo - this is the generally how the freewheel guts are:

 

[Rix]

mega-range type 3 speed - which would otherwise be excellent!

Yah, running a 11t, 22t, and a 34T would be an excellent with a 50T+ up front.

I should find out today if I have chain line issues once I get a tire on there. Hopefully it won't be too bad, if it's going to limit the gear range that much then I might have to try something more like your setup. I like the fact that the dnp has an 11 tooth sprocket so it will likely be staying on there. A new crankset with 36/54 similar to yours would be the option to try next.

Yah I am curious as well, look forward to your findings.