Shorter Crank Arms on Levo / Kenevo?

[UKPHOTO]

New Bosch motors already allow for software tuning for different crank arm sizes and Bosch boss runs 152mm on his personal bike so it's already here. Just need rest of the manufacturers to catch up and realise we can conceivably go where non ebikes go and risk more pedal strikes.
Very fast growing industry now but I think manufacturers were still somewhat in the mindset that these are mountain bikes with a pedal assist motor, where (as riders are showing them) this is actually really a completely new genre and should be treated (designed/made/planned) as such.

 

[R120]

Shorter cranks are far more noticeable if clipped in than on flats, since when clipped you feet placement is fixed, whereas on flats you are never putting your feet in the same place. Large platform pedals which as Crank Brothers probably help if going shorter.

If you ride clippers you will notice the difference far more.

I went from 175 to 160, but also went from Nukeproof Neutron pedal to large Crank Brothers Stamps, so whilst from spindle to spindle the platform has gone down, from pedal leading edge to trailing edge has not reduced much.

 

[Kiwi in Wales]

Hi @James-mtb,

I did not noticed anything when I changed over to 150s. When I had my 150 cranks on my ebike a number of people rode it on ups, downs, tight single track etc. I never mentioned anything about the shorter cranks until after the ride had finished. Not one of them noticed the shorter cranks and the only comment I got back was ‘ah that is probably why I didn’t get any pedal strikes’.

Look, It really depends on what type of riding you are doing. If you are a chilled rider that does not want to get into fast technical, ups, downs, single track or slow ‘trials type’ riding etc, then shorter cranks won’t really make a big impact to you. However, if you are planning on doing the above then yes, they will help.

They are not a huge cost upgrade option either so if they don’t work out for you it is not a big hole in your pocket. Have you watched the video @Rob Hancill released on shorter cranks? If not, have a look.

I am currently running with 137 cranks and happily doing the same trails just as quick as I was before. Including the downhill sections.

People love to poo poo things when they haven’t even tried or tested the actual item.... hmmm where have I heard that one before...... ah yes, I know when it was, it was when ebikes became a main stream item and load of haters suddenly appeared from nowhere?

This is a snapshot of the ride I completed yesterday, and yes, I know, Strava isn’t very accurate.... but at least it gives me a rough idea that my new 137 cranks are not giving me too many performance issues.

 

[Rob Rides EMTB]

My Crank vid goes live tonight ?

 

[ccrdave]

so Miranda cranks fitted this morning, one came a little bit chipped but it will get more very quickly so no drama, had to clean the threads as the anodising had overspilled a little.
I had to raise my saddle a little for perfect peddaling position and I use about one cog smaller than I would normally for a given situation but other than that there is no difference except NO PEDAL STRIKES yay!!

 

[UKPHOTO]

so Miranda cranks fitted this morning, one came a little bit chipped but it will get more very quickly so no drama, had to clean the threads as the anodising had overspilled a little.
I had to raise my saddle a little for perfect peddaling position and I use about one cog smaller than I would normally for a given situation but other than that there is no difference except NO PEDAL STRIKES yay!! View attachment 2766 View attachment 2767

Yeah, both threads on one of my arms was horrid giving me aggro, especially fitting fiddly self-extracting cap.
Not had to move saddle myself but also fit very thin Crank Brothers Stamp large which helps.
Loving new setup ATM.

 

[Kiwi in Wales]

so Miranda cranks fitted this morning, one came a little bit chipped but it will get more very quickly so no drama, had to clean the threads as the anodising had overspilled a little.
I had to raise my saddle a little for perfect peddaling position and I use about one cog smaller than I would normally for a given situation but other than that there is no difference except NO PEDAL STRIKES yay!! View attachment 2766 View attachment 2767

Great to hear Dave!

How are you getting on with the coil shock? I haven’t looked back since getting mine changed over.

I just noticed you have the quad piston XTs on. How are they performing in comparison to the Saints?

 

[ccrdave]

cranks are spot on, coil shock is fantastic there one fast peddally track i ride which is very bumpy with the old shock i had to stand all the way, with the coil I can just sit there and it feels like im riding on the road.
in my opinion, the brakes are miles better than the saints, much more modulation and zero problems

 

[Rob Rides EMTB]

Time for another cheesy Rob edit!!

 

[ccrdave]

bit more info, just back from riding, picked all the biggest rooty trails this morning and pedalled over everything, got two very slight pedals "kisses" if I had done that with the standard cranks I would have been on my arse about 5 times.
so cadence is higher by about 10rpm and pedalling feels much more circular if you know what I mean and I have no hard evidence to back this but I am sure the bike is faster or at least my peddling is more efficient so I am quicker
all I can say is if you are considering this upgrade do it you will not regret it

 

[Donnie797]

Time for another cheesy Rob edit!!

Thanks for the video Rob (btw. your edits are excellent, the're always fun and instructive to watch).

I definitely will go with shorter cranks as soon as i have an e-mtb. The costs are not a big deal, so it's a no brainer.
I just wonder why not all manufacturers go with shorter cranks from the start, or at least offer them.

On my first and only e-mtb ride so far, i rode a "Ghost SL AMR X Hybride" which comes with shorter cranks (155mm). I didn't had a clue about e-bikes at that time, nor have i ever experienced shorter cranks. But as soon as i rode the bike the first meters in front of the shop, i've noticed something is different (my non-e bike is the same model, just without the motor) and a bit confused i've asked the dealer if that bike has shorter cranks or something else is weird. "Yes, the cranks are 155mm" he said. So i really could feel a difference, but it wasn't a bad one, just slightly different. I test-rode that bike on a short trail that day and i absolutely forgot about the shorter cranks right after mentioning it. The brain adopts to it stunningly fast it seems.

 

[Rob Rides EMTB]

Thanks Donnie. I agree you get used to it.

I just wonder why not all manufacturers go with shorter cranks from the start, or at least offer them.

My money is that they will all go to shorter, sub 160mm crank arms within 2 years.

 

[R120]

Thanks Donnie. I agree you get used to it.


My money is that they will all go to shorter, sub 160mm crank arms within 2 years.

Agree, especially now there are a lot more options out there such as Srams new range of cranks

FYI The Ghost actually use rebranded Miranda’s

 

[Highflyer]

Just called Bryan at Dillglove. Super service. 150mm en-route !!

 

[Rob Rides EMTB]

Just called Bryan at Dillglove. Super service. 150mm en-route !!

I recon he’s sold a few now!

 

[Hinett]

Just watched an embn video from eurobike and hope are starting to sell crank arms between 150-170 mm for Brose and Bosch motors. So it does look like it’s the next thing in e mtbs

 

[Cyclejunkie]

Just watched an embn video from eurobike and hope are starting to sell crank arms between 150-170 mm for Brose and Bosch motors. So it does look like it’s the next thing in e mtbs

You mean “rocking horse shit” easier to get hold of that

 

[R120]

I think he's talking about the new Sram e-bike specific crank range that is coming out next year, expanding on their current offering of one crank. Basically 150mm thought to 170mm, for Shimano, Bosch and Brose

 

[ccrdave]

no deffo HOPE i have seen pictures of them

 

[R120]

Are yes i saw Hope are doing some as well - i miss read the post as thought he was saying hope to see more cranks - doh

 

[Mabman]

Is the reason you are all using shorter cranks because you get pedal strikes if you stop pedaling enough to properly time your cranks like you have for years on your dino mtb? Because the assist shuts down is it harder to work your way through tech as it takes whatever amount of crank movement to reactivate? I use my normal 170's I have an all my bikes, road and mt. and although I ride root and rock tech as much as I can and do get the odd pedal strike it really isn't an issue as I just do the same routine I have always down when timing my cranks. Grab just the slightest amount of rear brake and keep steady pressure on the pedals as you move them were you want release the brake lever and as you have maintained pressure the PAS is still activated you have instantaneous response. Back pedaling or ratcheting your cranks as you might have in the past will de-activate the system.

Anyway that is what works for me. Carry on.

 

[Levo_+_Hope]

They fit, had mine on a while

 

[Doomanic]

There’s been talk of moving the seatpost to get the right saddle height with shorter cranks, but no mention of shifting in back to get the fore/aft position optimum for pedalling dynamics. Is anyone doing that?

 

[Donnie797]

Is the reason you are all using shorter cranks because you get pedal strikes if you stop pedaling enough to properly time your cranks like you have for years on your dino mtb? Because the assist shuts down is it harder to work your way through tech as it takes whatever amount of crank movement to reactivate? I use my normal 170's I have an all my bikes, road and mt. and although I ride root and rock tech as much as I can and do get the odd pedal strike it really isn't an issue as I just do the same routine I have always down when timing my cranks. Grab just the slightest amount of rear brake and keep steady pressure on the pedals as you move them were you want release the brake lever and as you have maintained pressure the PAS is still activated you have instantaneous response. Back pedaling or ratcheting your cranks as you might have in the past will de-activate the system.

Anyway that is what works for me. Carry on.

Hm, i don't get it, but maybe i missunderstood something. If i pedal and my pedal will hit an oncoming root, i have to stop pedaling (or back pedal a bit). If i brake or not doesn't matter, that pedal will hit the root if i don't stop pedaling. Braking would just change my speed but the pedal rotation is still exactly the same. I don't have a clue how you move your pedals to a position you want while keeping (forward?) pressure on them, while braking, but not back-pedaling/ratcheting and all this on a steep technical uphill climb?

There’s been talk of moving the seatpost to get the right saddle height with shorter cranks, but no mention of shifting in back to get the fore/aft position optimum for pedalling dynamics. Is anyone doing that?

I would just check the angles and joint positions and reposition the seat to those like you do with normal cranks. If cranks get shorter, the saddle position should be fitted to the new length. By raising the saddle you get the saddle back a bit automatically, but probably not enough to fit a 2cm shorter crank. And the downside of this is, with shorter cranks and lifted and moved back saddle, there comes an increase of the reach and maybe you want to raise your bar a bit as well to regain the same position. Another downside is that you will loose quite a bit of downward pressure on your outside foot in sharp turns - this is why low bottom brackets and flatter pedals are so good on the downhills-shreddings. All in all it really is a change of geometry.

 

[Highflyer]

There’s been talk of moving the seatpost to get the right saddle height with shorter cranks, but no mention of shifting in back to get the fore/aft position optimum for pedalling dynamics. Is anyone doing that?

Unlike road bikes rider position is not a constant and when combined with motor assistance I think the most important goal here should be overall comfort rather than efficiency.

 

[ccrdave]

For what its worth i did lift mine up and back my knees are very sensative to rider position and anyway the slightly increased reach is welocome. My one complaint on the levo not enough reach

 

[Doomanic]

I’ve probably got a 120mm stem in the garage if that’ll help...

 

[ccrdave]

Lol i got a 70 on there the mo

 

[Mabman]

"Hm, i don't get it, but maybe i missunderstood something. If i pedal and my pedal will hit an oncoming root, i have to stop pedaling (or back pedal a bit). If i brake or not doesn't matter, that pedal will hit the root if i don't stop pedaling. Braking would just change my speed but the pedal rotation is still exactly the same. I don't have a clue how you move your pedals to a position you want while keeping (forward?) pressure on them, while braking, but not back-pedaling/ratcheting and all this on a steep technical uphill climb?"

Crank timing is about reading the trail in front of you and anticipating where your cranks will need to be in order to not strike whatever rock. root or rabbit that your mind says uh oh about. This as I mentioned is not exclusive to eMTB's and if you have ridden much dino MTB just think about what you do to avoid them using your conventional crank size. Back pedaling is out for this method as I mentioned because it will just shut down the PAS.

Best I can tell you is next time you ride your bike play around with the concept a bit as it can be felt even in a parking lot. Get going and apply the slightest pressure to the brake lever while slowing down your pedal stroke enough while still applying forward pressure to position them for a ghost obstacle, which shouldn't take a full revolution of the cranks. Release the brake and continue pedaling without pause. It is the slight resistance against the brake that keeps the pedal pressure constant enough to keep the PAS activated and although you might slow down a little the instant engagement gets you back up to speed quickly. For trial purposes it might help to actually over accentuate this and grab more brake while keeping pedaling against the resistance it provides.

If you have brake cutouts btw this won't work but not many bikes have them these days as torque assist systems are refined enough these days over the old cadence sensing ones that would stay activated for a bit after you stopped pedaling that they are not necessary.

 

[Donnie797]

"Hm, i don't get it, but maybe i missunderstood something. If i pedal and my pedal will hit an oncoming root, i have to stop pedaling (or back pedal a bit). If i brake or not doesn't matter, that pedal will hit the root if i don't stop pedaling. Braking would just change my speed but the pedal rotation is still exactly the same. I don't have a clue how you move your pedals to a position you want while keeping (forward?) pressure on them, while braking, but not back-pedaling/ratcheting and all this on a steep technical uphill climb?"

Crank timing is about reading the trail in front of you and anticipating where your cranks will need to be in order to not strike whatever rock. root or rabbit that your mind says uh oh about. This as I mentioned is not exclusive to eMTB's and if you have ridden much dino MTB just think about what you do to avoid them using your conventional crank size. Back pedaling is out for this method as I mentioned because it will just shut down the PAS.

Best I can tell you is next time you ride your bike play around with the concept a bit as it can be felt even in a parking lot. Get going and apply the slightest pressure to the brake lever while slowing down your pedal stroke enough while still applying forward pressure to position them for a ghost obstacle, which shouldn't take a full revolution of the cranks. Release the brake and continue pedaling without pause. It is the slight resistance against the brake that keeps the pedal pressure constant enough to keep the PAS activated and although you might slow down a little the instant engagement gets you back up to speed quickly. For trial purposes it might help to actually over accentuate this and grab more brake while keeping pedaling against the resistance it provides.

If you have brake cutouts btw this won't work but not many bikes have them these days as torque assist systems are refined enough these days over the old cadence sensing ones that would stay activated for a bit after you stopped pedaling that they are not necessary.

Ok thanks, i think i got it now and have to try that as soon i do have my e-mtb.
I'm just used to conventional bikes yet, where braking and pedaling forward against the resistance would not change the pedal movement at all - they would still do the same rotational movement and would end on exact the same point of contact, just with reduced speed. Hope that sounds logic