Dave's 80:1 RC mid drive kit build log

Discussions related to motors other than hub motors.
This includes R/C motors, botttom bracket, roller and geared drives.
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Re: Dave's 80:1 RC mid drive kit build log

Post by 12-C » Apr 11 2018 12:37am

https://www.pinkbike.com/buysell/2172101/

might be a good option for some.

I'm looking to use this cog on the standard tensioner arm because it's got a nice long tooth profile.

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Re: Dave's 80:1 RC mid drive kit build log

Post by tangentdave » Apr 11 2018 10:57am

I like this style of chain retention, let the derailleur pull against something fixed to limit chain bounce. The bearing mounted jockey wheel is more correct IMO than the C-Guide which is just a plastic slider for $35. PLA might be too brittle for long term but maybe I'm wrong. The 3D printable nylon material is way super tough, near indestructible (and harder to print). Support this man.

Ace, gen2 is lighter but I wouldn't say buy a whole new gearbox because of it. If the NeuMotor 3215 compares to the Astro 3220, that could be significant weight savings. Not sure when I'll be able to build the unit for myself, much late work customer work comes first.
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Re: Dave's 80:1 RC mid drive kit build log

Post by FastJohnny » Apr 15 2018 8:26am

Any of you guys skate 30 years ago?

https://www.lowbrowcustoms.com/monster- ... ioner.html

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Re: Dave's 80:1 RC mid drive kit build log

Post by 12-C » Apr 15 2018 9:44pm

FastJohnny wrote:
Apr 15 2018 8:26am
Any of you guys skate 30 years ago?

https://www.lowbrowcustoms.com/monster- ... ioner.html
the price tho!!! :shock:

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Re: Dave's 80:1 RC mid drive kit build log

Post by Leeleeducati » Apr 20 2018 1:12pm

Got my kit, nice piece of mechanical tech. Got a few questions Dave;

1. What are the two wires coming off the motor for? Temp? (bottom right).
2. What are the three wires coming off the ESC for? (top left).

Notes: If anyone else needs to clear the PF adapter to mount to ISCG, you'll need a 51mm opening, the bracket I received was <50mm, had to open it up a mm to avoid having to remove the adapter every time.

Still working on chain line. Having non standard brackets, suspension, BB and spacing I was expecting this... I'll keep everyone in the loop on my findings, at first glance it appears to be a simple 6mm spacer behind the bracket (between frame) and it should keep the lines correct.
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Re: Dave's 80:1 RC mid drive kit build log

Post by FastJohnny » Apr 20 2018 1:16pm

Temp sensor from the motor. Programming lead for the CC ESC is the 3 wire connector.

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Re: Dave's 80:1 RC mid drive kit build log

Post by Leeleeducati » Apr 20 2018 1:26pm

Can the temp sensor be plugged directly into the cycle analyst?

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Re: Dave's 80:1 RC mid drive kit build log

Post by FastJohnny » Apr 20 2018 1:27pm

Leeleeducati wrote:
Apr 20 2018 1:26pm
Can the temp sensor be plugged directly into the cycle analyst?
Yup

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Re: Dave's 80:1 RC mid drive kit build log

Post by tangentdave » Apr 20 2018 2:11pm

I've been meaning to clarify this part.

Image

The 6pin and 2pin jumper run down to the BB area. The 6pin is CA power/ESC throttle; 2pin is temp sensor inside the engine. If the temp sensor line becomes disconnected, the CA will read 1100C and not allow the motor to run.

Throttle input is the black 3pin behind the screen. The plastic probe is the wheel magnet sensor. These are the only connections used for the kit, obviously all the normal CA functionality is still available (aux input, PAS, programming lead, battery voltage pass-thru).
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Re: Dave's 80:1 RC mid drive kit build log

Post by Leeleeducati » Apr 20 2018 2:16pm

Is the 1100C something you program in the CA’s that come with the kit? If I’m using my own CA will the ESC not run if I don’t have the temp sensor connected?

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Re: Dave's 80:1 RC mid drive kit build log

Post by tangentdave » Apr 20 2018 4:21pm

Temp protection must be enabled in the CA setup menu:
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The temp sensor is a KTY84/130, use these settings:

Sensor Type: Linear
0 Deg: 0.45V
T Scale: 262.1V/deg
Thrsh Temp: 160
Max Temp: 170
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Re: Dave's 80:1 RC mid drive kit build log

Post by BonesNis » Apr 20 2018 5:12pm

Hey Dave

Any updates regarding Batch 1 second gen orders?

Thanks.
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Re: Dave's 80:1 RC mid drive kit build log

Post by tangentdave » Apr 21 2018 12:32pm

Kits are shipping. It's about 10 days from zero to completed kit at the moment, working two kits at a time, top of the list to the bottom. Next two are on the way to Italy. It obviously took longer than anticipated to fine tune the process/pieces, but I am happy with the design and gearbox. Hope all the patient supports get what they paid for, I think these make a great bike.

Wider spaced cooling fins; surface area was reduced by only 15% but allows better airflow to the deep corners of the fins and reduces the machining time.

Slightly revised eccentric gears made from pre-hardened 4140 allow for much greater grease loading, now 30mL is sealed inside. Maintenance interval still TBD.

Addition of hBN seems to reduce gearbox heating. Anecdotal evidence from initial break-in of gearboxes on test bench; have yet to exchange grease in my own ride. Customer units will all be getting hBN grease.

No reports of trouble (yet) with any ver1.5 or 2nd gen units.



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Re: Dave's 80:1 RC mid drive kit build log

Post by Leeleeducati » Apr 21 2018 12:58pm

Dave's right, these do make for a great bike. I'm still in the install stage, but having the Tanget mechanics mounted to the bike makes it look and feel awesome. I'm fairly sure I'm at around 40lbs, I'll weight once I get it complete.

So the chainline drama is over and the motor is for the most part installed, still have to work on electrical. I had to space 7mm from the ISCG tab (bottom right), then 3.75mm spacer to the pedal chainring (bottom left) and had to turn 2mm off the chainring adapter (top left) and it all came together with perfect chainlines to pedal and for the drive. I have to make custom spacers now for between all the points on the mount to the ESC bracket.

Now questions...Dave, is there an optimal number of links on the drive chain? I linked it as you can see in the pic, and if i go one more the tensioner needs to do more work to hold it up or one less and the chain is almost straight.

Also, how important is the strap around the downtube? None of the three supplied in the kit work for my frame. I actually needed something in between the longest and the middle strap. Is the strap just to hold everything in place with minimal forces exerted to it? I'm debating on milling something from the front derailleur mount (obviously not used) to the Tangent mount to hold it in place. Bolting the drive side mount with 3xM6 bolts to the ISCG already keeps things in place solid!
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Re: Dave's 80:1 RC mid drive kit build log

Post by FastJohnny » Apr 21 2018 1:20pm

If you mount in the triangle use the strap. Otherwise the motor will move back slightly under torque and tighten those B.B. cups to a point they’ll never come out.

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Re: Dave's 80:1 RC mid drive kit build log

Post by tangentdave » Apr 21 2018 2:30pm

I hate that strap. This is my least favorite of the install. In the push orientation the strap only holds the drive against the frame. You should secure the motor against riding forces, probably nothing bad would happen if not, but just do it. A big zip tie works as well.

The chain wrap looks right, you're saying more tension is needed? You might have to drill a new hole in the mounting plate to move the spring anchor tighter. I'll find us a stronger spring.

Spacers, what length do you need? I start with 5/16" OD aluminum spacer, trim to length then powdercoat (I bet flat black spray paint would match pretty well).
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Re: Dave's 80:1 RC mid drive kit build log

Post by BonesNis » Apr 21 2018 5:04pm

In theory, I believe the tensioner Dave designed is the way to go as it is simple and easy enough to adjust, remove, etc. But it could use a more robust spring in that the current spring isn't strong enough to keep steady tension on the motor chain.

Thanks.
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Re: Dave's 80:1 RC mid drive kit build log

Post by Leeleeducati » Apr 22 2018 4:22pm

Does the Castle Talon ESC care about order when connecting the three bullet connectors coming off the motor? Can I plug them in any one of the three bullet slots?

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Re: Dave's 80:1 RC mid drive kit build log

Post by BonesNis » Apr 22 2018 5:57pm

My understanding is if you plug the three connectors from the motor to the ESC and the motor runs backwards, just switch any two of them and it will work. Happened once to me and this i what Dave told me to do.
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Re: Dave's 80:1 RC mid drive kit build log

Post by robertpaulson » Apr 23 2018 9:22am

might be worth a look for those after a different crank option

https://singletrackworld.com/2018/04/pr ... ur-e-bike/

no idea if there is some proprietary layering going on inside the drive or how they would fit vs standard isis

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Re: Dave's 80:1 RC mid drive kit build log

Post by Mugenski » Apr 23 2018 7:11pm

First off clean build Lee. I regret not getting a frame that could mount the tangent in the triangle.

The drive chain Dave sent fits perfectly to remove without pulling a link. A stronger spring would be a nice addition. I don't think I'd want to run the chain too tight that I couldn't get it off easily but that is just me. Just flip any two connectors if the motor runs backwards, ESC doesn't care. Also you can tap the battery eliminator circuit on the talon for a little accessory power. Up to 8v if you connect with the castle programmer. Nice to power LED lights, ideally stuff that takes 2s. Easy to run the leads up to the dash with everything else. If you ever want to ride Lee let me know. I think there are a few of us in the GTA.

Been enjoying 14s, going to try and get my old gopro out and film some hill climbs. Tired of the bashing by those hub wheel meanies :| I am so impressed with this kit. Keep up the great work Dave. It's great to see recommended improvements actually taken to heart for the betterment of a product. Keep it up :)

I think this is the heatsink you are using Dave, can you confirm?
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Re: Dave's 80:1 RC mid drive kit build log

Post by BonesNis » Apr 23 2018 7:26pm

Perhaps a pulley that has longer teeth might stay on the motor chain more robustly...Thoughts?
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Re: Dave's 80:1 RC mid drive kit build log

Post by tangentdave » Apr 23 2018 8:39pm

The jockey wheels I bought are all 11t. More teeth are available for cheap, would effectively tighten the spring.

Notice there's only 1 of those heat sinks left in stock...I have the rest. The dimensions of that heat sink fit the Talon well, the slots for the hold down screw are just wider than the ESC. You'll want two heat sinks to cover the whole ESC, these guys are also a good fit:

Image
https://www.arrow.com/en/products/ats-1 ... -solutions
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Re: Dave's 80:1 RC mid drive kit build log

Post by fullofdays » Apr 24 2018 2:36pm

Can anyone pm me with a bike builder/shop on the east coast (preferably) that can help me sort out my build? I'm coming up with a blank for ebike shops/builders.

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Re: Dave's 80:1 RC mid drive kit build log

Post by 12-C » Apr 24 2018 9:29pm

fullofdays wrote:
Apr 24 2018 2:36pm
Can anyone pm me with a bike builder/shop on the east coast (preferably) that can help me sort out my build? I'm coming up with a blank for ebike shops/builders.
Honestly, your best bet is to ask around here and save yourself the markup and mistakes...

It might seem daunting, but I was essentially in the dark coming back to bicycles from a decade and half away from them. Not knowing anything about BB/axle/size standards etc etc. but just read around and you will get it, I thought it would be impossible but it wasn't. Steep learning curve but now I tend to know more than most bike shop people given how much mix and matching and work arounds are needed sometimes to make something like this work on a pedal bike.... Daves kit basically is bolt and go. You'll figure it out. read around and ask questions. most people here are eager to share their experiences!

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