I want 180mm cranks on my Ebike.

[leovendramini]

I have Dillinger Opia Ebike which has 170mm cranks.I would really like to change them for 180mm but I don`t know how to go about buying the correct components.I am finding it is not an easy matter.If I could find the parts,I would get them installed by the lbs.There 53T units out there which is the number on the Opia but the BB compatability seems to be a big problem.Can anyone help?

[MattyK]

a) why?
b) 180 is not a common size. Typically 175 is as long as you’ll commonly get
c) in photos is looks like a square taper crank. So there should be options available.

[A_P]

not concerned about pedal strike?

[uart]

I have Dillinger Opia Ebike which has 170mm cranks.I would really like to change them for 180mm but I don`t know how to go about buying the correct components.I am finding it is not an easy matter.If I could find the parts,I would get them installed by the lbs.There 53T units out there which is the number on the Opia but the BB comparability seems to be a big problem.Can anyone help?

Hi leovendramini. Just wondering how tall you are (or what is your inseam measurement).

Remember that extra leverage at the crank can be substituted by extra leverage in the gear ratios, so longer cranks don't necessarily give you any advantage unless your legs are quite long (and then there might be a small bio-mechanical advantage to them).

Also, I thought that one of the reasons for having an ebike was so that things like minimal weight and maximal bio-mechanical efficiency weren't all that paramount. When I look at how the majority of ebikes are set up it certainly appears to me that weight and bio-mechanical efficiency are not the most important things on the minds of the owners.

[Duck!]

a) why?
b) 180 is not a common size. Typically 175 is as long as you’ll commonly get
c) in photos is looks like a square taper crank. So there should be options available.

My bold. Actually quite the contrary. 180mm is a decidedly uncommon crank length; typically only found in the highest level components. And none of them use square taper any more.

I do have to repeat, and agree with the question "why?" Unless you're pushing 7-foot tall, there's very little biomechanical reason to warrant 180mm cranks.

[madmacca]

I have Dillinger Opia Ebike which has 170mm cranks.I would really like to change them for 180mm but I don`t know how to go about buying the correct components.I am finding it is not an easy matter.If I could find the parts,I would get them installed by the lbs.There 53T units out there which is the number on the Opia but the BB compatability seems to be a big problem.Can anyone help?

170 to 180 is a huge jump in crank length. If you feel 170 is too short you may want to consider some intermediate increases.

[baabaa]

Remember that extra leverage at the crank can be substituted by extra leverage in the gear ratios, so longer cranks don't necessarily give you any advantage unless your legs are quite long (and then there might be a small bio-mechanical advantage to them).

I have used 180mm from the time I spent real money on a good bike, if someone is tall it is not about any sort of bio-mechanical gain, it is what feels right. I am a slow twitch body type for more or less anything longer distance stuff, running, swimming and bike riding and 180 just feels better on the bike. I also have them on my ss 29er which is pretty common. The lance type high cadence spinning is just not for me so now anything less than that just feels odd.
I guess the only reason you would want 180 on an ebike is for the sit-on feel while coasting but they are becoming hard and costly to get apart from mtn bike cranks so would it really help?

[leovendramini]

not concerned about pedal strike?

No,there is plenty of clearance.Thanks.

[leovendramini]

Having considered all your replies,I think 175mm is the way to go.The opia uses a square taper so may I have suggestions on what to search for as this smaller length appears to have more options when it comes to purchasing.As a 6ft. rider I am always conscious of needing that little extra stroke length and finally I have decided to `put the money down`

[twowheels]

may I have suggestions on what to search for

175mm cranks

[leovendramini]

may I have suggestions on what to search for

175mm cranks

Should I just be specific about square taper and then any brand will do or is there more to it?

[uart]

Yes 175mm should be a comfortable size for you. I'm a similar height (and 86 cm inseam) and I feel 175mm is about right for me (though I have to admit that I do also ride 170's sometimes, and TBH the difference is quite small).

may I have suggestions on what to search for 175mm cranks
Should I just be specific about square taper and then any brand will do or is there more to it?

- How many teeth on your chainring? Do you want to keep the gearing the same?
- Does your current chainring unbolt from the crank? Do you want to re-use it? How many bolts and what BSD?
- Your bike has no FD. Do you need a single speed crank, or are you ok with having a dual chainring crank with just one ring fitted?

TBH 175+ can be hard to find in the old square taper format. I've got two of them here (old Shimano 600 stuff in 175), but I've had them for decades. In square taper 170mm seems to be totally ubiquitous unfortunately. Looking at online stores I can't seem to find anything over 172.5, so let us know if you find something because I'm interested too.

[leovendramini]

I have 53 T and want the same.The Ebay ones have 53/39 and I am OK with carrying an empty spare.My LBS guy told me I cannot just buy the cranks alone.I am pig ignorant about all this.

[uart]

I have 53 T and want the same.The Ebay ones have 53/39 and I am OK with carrying an empty spare.My LBS guy told me I cannot just buy the cranks alone.I am pig ignorant about all this.

Are you looking to do the work yourself? Obviously you'll need a crank removal tool as well.

But yes, you may or may not get away with just replacing the cranks with a double. I've found that different brands of square taper cranks can be very slightly different in the extent to which they slide on, so there can be a few mm either way in the chainring alignment when you replace the crank with a different type. If you're unlucky this might place the inner chainring (and in particular the little attaching fasteners) a little too close to the drive side chainstay to give clearance. You'd just have to try it and see.

[leovendramini]

I have 4 units on my Ebay watch list but I don`t know how to post them to you and get your opinion on them.If you give me your email address I can send you the listings .

[Bunged Knee]

If you want to PM to uart, just click on the red outline like that and it will send it to him.

[Rodgerbiltit]

SPÉCIALITÉS-TA make square taper cranks up to 185mm
https://www.bikeonlineshop.net/speciali ... ght-silver
You can even have different colours too! I went with silver.
Yes - expensive, but you can "dial in" whatever combination is compatible...
I guess it depends how determined you are?

[leovendramini]

Thanks for the post,I will keep searching the local market .If only someone would invent and sell crank extensions .how much easier things would be.

[mikgit]

If only someone would invent and sell crank extensions .how much easier things would be.

You need a Look Zed crank...well OK not applicable here, but it is adjustable...(170, 172.5, 75, pick a length)

[uart]

If only someone would invent and sell crank extensions .how much easier things would be.

You need a Look Zed crank...well OK not applicable here, but it is adjustable...(170, 172.5, 75, pick a length)

Yes, probably not applicable here (not for square taper), but they certainly are a neat idea.

[leovendramini]

Some smart Aussie with a small machine shop could make a good living making and selling crank lengtheners world wide.The entire unit only needs to be 70mm long.I have done the research and no such animal exists.

[mikgit]

If only someone would invent and sell crank extensions .how much easier things would be.

You need a Look Zed crank...well OK not applicable here, but it is adjustable...(170, 172.5, 75, pick a length)

Yes, probably not applicable here (not for square taper), but they certainly are a neat idea.

Yeah, they're a 1 piece crank...so I don't think they fit any BB apart from Look frames (697/795), but they are "lengthen-able"--ish

[uart]

Some smart Aussie with a small machine shop could make a good living making and selling crank lengtheners world wide.The entire unit only needs to be 70mm long.I have done the research and no such animal exists.

The problem is that you first need a good "workable" design for this crank extender.

If you are thinking in terms of something like the image below, it wouldn't sell. Not in today's market, just no way. Far too heavy and clunky. Not to mention that in order to be able to fully screw in the pedals means that such a design necessarily means increasing the pedal to pedal distance by at least 2cm which would change the pedaling ergonomics.

Another problem is that most people (but particularly competitive cyclists) would want only quite incremental changes. The fact is that most people will have an optimal crank length for comfort and efficiency, and only require quite small adjustments of +/- a few mm around that point. Any system using multiple 9/16" holes will require at least 1.5 diameters hole separation (at under 1 diameter separation the holes run together), which makes the minimum "tweaking distance" over 20mm - that's far too much.

That's the problem, I've never see a real working design for a crank extender (that could be retro-fitted to any crank) that was even close to being worthwhile.

[leovendramini]

In my mental image,only the 2 bottom holes are necessary as there would be only one lengthening option.70mm would be total length and comp. riders would have no use for it as their cranks are dedicated anyway.These would be for the non pro who just wants some extra mechanical advantage.Had the design in fig 2 dispensed with all those options it could have been a success.Thanks for the post.

[Jmuzz]

Some smart Aussie with a small machine shop could make a good living making and selling crank lengtheners world wide.The entire unit only needs to be 70mm long.I have done the research and no such animal exists.

Modern cranks are being designed for maximum stiffness which is the whole reason they aren't just a cheap $20 arm on each side anymore.
Add extention bits and it may as well just go back to the cheap easy swap left and right arms again.