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

Dave is possible to use a chain tensioner device?
I have make my own design for cyclone motor and I have done a laser cut where I have put 36 tiny holes around the bottom bracket hole one every ten grades so I can opened these holes and fix the plate of the motor on the iscg05 and in this way over this I can put a chain tensioner, I will make some pictures to you.
 
Are you now using Direct Mount Cranksets now ?

Not yet, that's what we need to shave the weight. I don't know of a compatible crankset. Kranked uses a custom adapter between direct mount cranks and the Cyclone freewheel.

Spiros, we can use the ISCG tabs to secure the Tangent and I can also put new ISCG mounting points on the Tangent plate itself. Check out this GT Fury with their rotating BB, the drive is secured from rotating with the frame's ISCG tabs and I added separate mounting holes for the chain guide.

Tangent Fury.jpg
 
Dave,

In Regards to heavy ISIS Bottom Bracket, ( and heavy old school Square taper BB's also )
I have been wondering when we consumers can finally be rid of that old and heavy system of bearings for our cranks on bicycles.

A few years ago I got a Road/Gravel Frame that has a BB30 Shell , I did not like the Idea at first, but once I bought the Bearings and Crankset, and felt how very light weight they are and felt the improvement on how smooth they spin , I was very happy, not wanting to ever go back to having to use a Square Taper/ISIS , BB.

Now because of the fact that a Frame Maker has to make that frame with very precise tolerances , we are seeing more bikes going back to the Threaded BSA standard , or , still having a press fit BB, but one that can make up for the not so precise made BB Shell.

The newest form of Crankset for MTB's as you probably know is the Direct Mount Crankset System.

Now that I have a couple of used ones that I have taken apart, I see the advantages, and for E-Bike ( Mid-Drive ) DIY systems, I now think it is the way to go.

The BB for Direct Mount can be either press fit, But also good for us a thread in / outboard bearing can be used, that takes off allot of weight from the old Square Taper and Cartridge BB's'

And

By using the easily removeable cranksrms from the spindle, just a custom made for E-Bikes Spindle can be made,
A
Spindle that is a couple of mm's longer that can accommodate both a freewheel , and two chainrings,
And
It can be made to allow the use of washers/spacers that can be put on either side of the chainrings and / or freewheel
so as to give us a better and custom chainline.






tangentdave said:
I greatly prefer the motor chain to use the inner chain position. It's visually cleaner, I can put a tiny 24t sprocket on the inside position which fits all frames, less lateral force. Downside is the derailleur chainring is about 1/4" farther outboard but straight chain is still in the middle of the cassette. The ISIS BB is needlessly heavy; a custom crankset might save a pound of weight. Four of the ACS freewheels on the motor have broken (one poor guy broke two in a row with less than 50 miles). No issues with the crankset freewheel.



Suggestions and criticism welcome. Updates of design and testing to follow.


-dave
 
Check out the Race Face Cinch, Direct Mount Crankset's

They are available with 30mm OD Spindles, and now available with 24 mm OD Spindles for use with many of the outboard bearings like Shimano Hollowtec II's

You can take off both of the Crank Arms and just change out the Spindle,

Race Face already has this available, if you bought a 68/73 long Spindle, but now are building up a Down Hill Bike, just call them and get the 83 mm DH Spindle

This is the Future I believe, you do not have to buy a whole new crankset, just the spindle .
 
Not having a mid-drive at this time, or even seen one in person , and
Not having the work you and Lightningrod's , PaulD , and others have done with Mid-Drives I can only guess.

one way is to make a spyder adaptor for the current freewheels. by drilling 4 holes in the freewheel
http://sickbikeparts.com/front-freewheel-cyclone/

http://sickbikeparts.com/front-freewheel-heavy-duty/

Make your own type of sypder adaptor like this ...
https://www.raceface.com/products/details/cinch-spider

Or

You can make a spider that slides onto the splined part of the Spindle. That would of course put the freewheel inside of the chainrings,
so
There is some engineering do do .
Here is a picture of the Spindle of a Race Face Cinch Design DD Crankset.
File too big, here is an online picture of their spindle ... https://www.raceface.com/products/details/cinch-spindle-kit-68-73mm





tangentdave said:
Right, this is the way to go. How do we get a freewheel onto the RaceFace Cinch?
 
Is really necessary work on the bottom bracket weight?
I meen guys we can have 6kw of power why you bother about Isis crankset?
Anyway I came from street use and freeride use of the bike I have broken several frames so I know what is gravity and hard core using of the bike, I don't bother about Isis cranks I feel safe with them and 6kw of power doesn't feel the difference and remember that the heavy duty Isis has "4" bearings so they can resist well on this kind of ebike.
Anyway it is only an opinion, I am not a super expert of Ebikes.
 
Here is what I actually use but I really want a tangent kit because I think that it really hard core
 

Attachments

  • image.jpeg
    image.jpeg
    92.6 KB · Views: 4,981
  • image.jpeg
    image.jpeg
    67.7 KB · Views: 4,981
Less Bottom Bracket weight is only one part of why we should get rid of Square taper BB's .

A benefit to the more modern BB's is that they spin much smoother.

Also

The Biggest Benefit to using a modern style Direct Mount Crankset is the substantial increase in Strength .

So

With the newer systems you / we get ... lighter weight , smoother operation, and ... most important , Stronger Spindles .

Add to that the ease to take off each crankarm with the self extracting bolts on DD Cranksets.
 
Also, those damn square BBs fail in the most annyoing ways, are hard to remove, therefore hard to clean and the bearings are tiny. I would welcome to get rid of them forever and replace them with the newer direct mount style any day
 
I suspect I got one of the last of Dave's kits before he moves over to outsourcing production. What a piece of kit! It's a real beauty and I am glad I picked one up. I will say though that battery choice is a key consideration. This kit has more power than sense and it likes a battery of the same vein. Looking forward to tweaking the kit for aggressive hill climbing as well. Have a bet in with a buddy that says I can't climb the local mountain that he rides down... Couldn't have picked a better kit to prove him wrong :D

Dave is always super responsive to my silly questions and I have total confidence in him and his products. If you're on the fence hurry up and pick a side, I'm sad I didn't pull the trigger a year or two ago when I was checking this kit out. A real gem.
 
Mugenski said:
I will say though that battery choice is a key consideration. This kit has more power than sense and it likes a battery of the same vein.

Out of curiosity, what battery setup are you running? :)
 
Sean9002 said:
Mugenski said:
I will say though that battery choice is a key consideration. This kit has more power than sense and it likes a battery of the same vein.

Out of curiosity, what battery setup are you running? :)

I got a decent deal on some lower C rating Tattu prismatic cells earlier this year. 390USD to my door (in Canada at that) for a little over 30Ah @ 50v. It's not ideal in the sense that they are lower C 5200mah 6s packs. I don't have a spot welder but I do have a hobby charger and some parallel boards for charging all those packs. Split into two 6 pack bricks at 15Ah each and while the vdrop on a single brick is disappointing, both bricks together stay cool even if riding aggressively and they push the amps I need with acceptable voltage drop. Some of the vdrop may be related to the harness and all the connections needed to make it happen; going to work on improving that over the winter. The droop is why I spec'd such a large pack. I wouldn't mind a really nice 15Ah or 20Ah frame pack but I'm more accustomed to prismatic hobby cells. Maybe one day... 21700 cells perhaps.

All that to say that the tangent kit is a blast. I popped the motor to crank chain yesterday so I made up a new one and a spare to keep with me. I've also bumped the power a little over what Dave sets it up for; I have a bad habit of pushing limits. Thinking of 1/8 chain and stepping down from a 9 speed cassette. I prefer to stick in the lower gears as they offer plenty of speed and more efficiency from a stop. Pedaling off the line would be ideal but I'm not digging all the shifting with the 9 speed.
 
Been riding the kit more and I am really enjoying pedaling along at a lower power level. Made a couple profiles for 500w and 1000w and just use it more as an assist and to make the hills more manageable. Quite a blast and should give the chains a fighting chance. It sure is fun to open it up though! The 3T 20:1 setup is really nice. I was skeptical at first but now that I've run it I am really liking it. I can lug it along in any gear and the motor is perfectly content. The hooligan/MX side of me just wants to remove the limiter and see what kind of burst power the Talon 120 will push (150+ burst likely) but I know better. Maybe just once :wink:

The kit is super quiet. Way quieter than what it was made out to be. If I can say this I assume Dave initially worked the reduction FOR the sound. Now that it's been made clear people want the quieter option I will say I think he's nailed it. The motor is the nosiest part of the kit so if you want stealth your best off keeping the RPM low, pedaling along in the high gears. If I'm pedaling along and don't want someone to suspect I just let off the throttle, stop pedaling and let the freewheel noise take over.

Now if I entertain my hunger for power... The phoenix 160 HVF offers a 'key' arm that could be independent of the CA. You lose the talon BEC for aux power however a CC BEC 2.0 would solve that and supports 14s. Interested in the 160 amp controller because the 3T motor has tons of thermal headroom, most people using cylindrical cells wouldn't want to stress them or the drive train with anymore power so I understand Daves choice in the Talon. In 30C weather I've only been able to push the motor to 100C, the controller had more trouble with the heat than the motor did. The end goal for this build is to climb the local ski hill and laugh at my buddy on the lift. Next up is an 8 or 9 speed cassette with a nice granny gear and well see how the hills can be tackled. On that note I think I'll put a 30T chainring on order as well.

I very much look forward to what is to come. Dave, please keep us updated on whatever you're working on now, I've got a couple friends who were sad to hear the kit wasn't available at present after riding it.
 
remove the limiter and see what kind of burst power the Talon 120 will push

I set all the Castle ESC's to 'insensitive' current control. This means 240A for the Talon, 140A for the HV80. The 120A and 80A rating are the 5 minute current limit for each ESC. Big power at low RPM means big phase currents. The Astro motors are tough enough to handle these currents reliably and the 3220/Talon are big enough to lug around at pretty low RPM with a moderate/heavy load. We could use a bigger heat sink on the Talon to do this for an entire 20Ah battery- my 40mph single speed Zerode can heat the Talon to warning beep in about 2 miles of 5-10mph of very heavily loaded use (steep boulder uphills with lots of wheelie, gnarly moto trails ). Because it's so small, it cools down quick though. If I'm not heavily loading the engine at 5mph, I can ride hard for 20Ah without a heat warning and ~100C motor temps.
brrrrraaaapp.

a big battery to minimize voltage sag is the best way to get more out of the system.



-dave
 
Just a little update:

Dave advised me a long time ago to try the kit with a 14s pack but I had been unwilling to spend more on batteries until my 12s set up was dead.

Luck would have it that a few cells in some of my 6s packs died. I braved having a go at taking them apart and turning two of the duff 6s packs to 4s and hey presto I now have a 14s pack....

Wow, I should have done this ages ago. Everything just came to life and that is from a 3220 kit that was already pretty brutal. I'll never go back to 12s again.

14s for the win.

Thanks again Dave
 
Ham said:
14s for the win.
Thinking of doing the same just last night Ham. Take two of my 6s packs and turning them into a large 2s5p pack for 14s.

I've also been playing with a few different profiles and accidentally unleashed the beast. By mistake I set to W limit while set to 99kw... Throttle was like an on/off switch. After reading the CA manual I understand why the throttle ramped hard with any application, 1% throttle would have been equal to about 1000w with that 99kW setting, whoops!

This did pique my interest in other throttle control methods. I liked the feel of pass-thru with the current limiter enabled (sub 50A) as opposed to current output control. Low speed control feels nicer and throttle is much snappier. Current limiter still kicks in but a little more noticeably than with throttle ramps and gains of current controlled output. Probably not advisable for more than 30 or 40A unless you like replacing your whole drive train on the greasing schedule. I did try passthru with 120A... Amazing to see what this kit is capable of even if only for a moment. Pretty sure those power levels tweaked some stuff, I do not recommend :roll:
 
More math, more engineering, more integration, more simplicity. Many changes in the works, still testing the validity of new features before I drop 'em on here to be ripped apart by the community. Fundamentally the same, but the product should be better in all respects. Initial weigh-in yesterday put the new 3220 unit at 7.5lbs for motor housing+gearbox, and some material still needs to be removed yet. Initially I'll only be making the 6kW version to keep things manageable over here. A smaller unit will be forthcoming.

There will be an upgrade path for the first generation customers to re-use their motor and electronics with the new hardware, otherwise all the parts are new....R&D continues, stay tuned...


-dave
 
> upgrade path ... reason number 127 why you rock Dave!!! Can't wait. You know how to reach me ;)

Dude props for even thinking about it!
 
Hey Dave,
I finally got around to building my Tangent Bike(Nicolai Helius AFT) which thankfully, is almost done. I think I may have bought one of the first kits you made back in 2015? Believe it or not it sat in it's box for the last two years while I straightened out my life... I did however, acquire all the parts for my build, taking care to buy only the very best. Now after reading this thread I'm getting super stoked about it again!! It should be done within the next couple of weeks and I just have a battery question. I built a self contained back pack where I'll be running 6-6s 8000mah 25c lipos in 3 pairs of 12s then in parallel, this will give me roughly 44 volts. After reading some of this thread I see people saying that 52v is the only way to go with this set up(Astro 3220 Motor)...Which now has me second guessing my self.
I'll be riding this bike hard, at times I'm sure I'll be far from civilization.
So for High Power & long range if you had to make a decision, what battery would be the best?
 
stuntmanmike said:
I built a self contained back pack where I'll be running 6-6s 8000mah 25c lipos in 3 pairs of 12s then in parallel, this will give me roughly 44 volts. After reading some of this thread I see people saying that 52v is the only way to go with this set up(Astro 3220 Motor)...Which now has me second guessing my self.

I'm currently running 12s and initially had setup in series how you are thinking (pairs of 6s packs for 12s then parallel). However I have since changed to running two parallel groups and then a series connection. It makes for easier handling/charging/balancing with fewer connectors. I'd have to break down the series connection each time to charge the packs (6s max hobby charger). Now I can leave the balance wires for each parallel group connected and only have to break one series connection instead of 6.

Another reason I went to paralleling first is it makes it easier to add more series connected packs. (xt150 connectors are fantastic for this). Now I'm putting an order in for a 2s pack so I can bump to 14s. Little extra wheel speed can't hurt.

My bike is coming together well. Tweaks here and there. Keeping the wiring clean is probably the most time consuming thing to get right.
 
Back
Top