Davinci Drive on Profile Dr-1 Bike

[stuntmanmike]

I normally frequent the E-skateboard forums & have completed 5 builds & now I'd like to try my hand at a bike. I am an avid free-rider & have raced Downhill bikes & motocross in the past & in that time I have acquired an arsenal of bike parts.
My idea is to build a silent dirt bike that I can ride on the many golf courses near my house without getting arrested :wink:.
I know this has been done here many times but the difference with this is this frame & parts spec. I'll use.
For The bike:
Frame: Profile DR-1
Forks- Marzocchi 888
Shock- Fox DHX5
Stem- Marzocchi Direct for 888
Bars-Race Face Diablos
Cranks- Profile 175mm
Hubs- Profile 36h
Rims- Alex Supra DH
Tires- High Roller 26"
Headset- Chris King 1.1/8"
Pedals- Crank Bros 50/50
Seat- Marzocchi DH
Post-Thomson elite
Brakes-Hope M-6
Shifter- Sram xo
Rear derailleur -Sram xo
8 speed cassette- Shimano Road
I recently purchased a complete Davinci Drive system from ebay complete with controller throttle & Astro motor. When it arrives my dilemma will be how to mount it to the frame. Without having it in my hands I'm only guessing as to the real size of the drive unit but I'll mount it on the bottom tube in front of the bottom bracket somehow. The batteries will be in a back pack lined with a lipo safe bag so that frees the frame space for the rest of the components.
I plan to post my progress here as I go, any ideas & constructive criticism is welcome.
I will begin the project when the Davinci drive arrives late next week....
I know that I'll need a few more things like a trials freewheel & bottom bracket maybe even a different crank set but I'll cross that bridge when I come to it.
Anything else anyone can think of that Ill need?

 

[panurge]

Hello...

Why do you think you´ll need a trial freewheeling crank?

isn´t Your plan to use a left chain for the motor as usual for Recumpence´s systems?

If yes, in addition to the normal difficults for an LH + rear suspension system (chainline, q factor, how to not heat the stays with the big rear chainring you´ll need to use, room for the rear calliper+chainring adapter, sprung tensioner for the return chain etc...) Your major problem will be to fit the left drive with the floating brake, I geuss it´s near impossible to realize without a big mod to the floating rod and leverage.....
I had 2 frames with floating brakes....none of them is able to host my Recupence drive....unless I dismount the float and use fix callipers, or fabricate a non-straight rod and fix it to the outer face of the axle leverage...

Remember: You will need at least a 56t rear chainring and a 148mm BB ( like an howitzer148 if your frame has 68-83mm shell or a gigapipe if has a 100mm one); if you plan to use the bike offroad, than a true return spring tensioner is needed, and some chainring bashs/keepers....
It´s a true challenge, but on the other side, If able to achieve a working setup, you will have a lot of fun.

CHeers

 

[panurge]

With my davinci drive and an Astro 3220 4t and a primary 5:1 reduction, I used with satisfaction and realiability these ratio:

- 16tENO to 61t gebhardt chainring (grand of 19.1:1) on a 24"x2.5 wheel : top speed out of charge 50Kph (amazingly 1kph per volt) super reliable climber setup (climbed wrong way a dirt-jump launching ramp>30% from few meters) no problem on starting from dead stops

- same but with a 26" wheel : top speed 56Kph anyway a good climber

-16t to 56t (grand of 17.5:1) with 24" wheel: top speed 54Kph (the best setup, used for this a birdy 56t chainring http://www.ebay.com/itm/Alloy-CNC-Chain-Ring-Wheel-Chainring-56T-Teeth-Bolt-for-Birdy-Bike-Bicycle-New-/271286519215?pt=AU_Sport_Cycling_Parts&hash=item3f29efc5af) this chainring is not strong as the 7075t6 gebhardt one unfortunately, noticed some early wear....

My top speed ever, has been reached using a 18t freewheel to the 56t with a 26" wheel: around 70Kph on flat asphalt with 2.5 hookwoorm tires, but this starts to be a bit crazy even on a DH-Fr bike for me, and you loose the feel that everything is ok while moving from 0 or at very low speed...

If the chainring adapter that comes with the kit you got from the bay is the old style type, than you need a magura gustav-m calliper that fit well, having pistons only in the outer side , but maybe just ask Matt for an upgrade so you could luckily use your hope set....

Be sure to use a strong enough HD 1/8 chain for BMX-trials, the chain is the most consumable part of this system, i guess...

An old beta Cycle analyst LRC or a new V3 is a good idea for a current based throttle, that gives a smoother and safer feel on your rides and ESC.
Run it with at least 15Ah of minimum 20c 12s Lipos (or also 10Ah for short tracks but with higher C nanotechs)
Be prepared to tune the Torque limiter clutch to find your proper good setup....

Good luck and feel free to ask for anything while your drive is arrived....

Cheers

 

[stuntmanmike]

Wow, thanks man that's a lot to think about....but I'm up to the task. I'm not dead set on using this frame either, I just wanted to do something with it...I do have another that will work better I think. I have a mongoose boot'r I got in a trade and I think the shape will lend itself better to this conversion i.e. high lower down tube and a good area to mount the drive at the bb..also I thought I needed a trials crankset in order for this to work and freewheel properly?

 

[panurge]

yes, there´s a lot to think about...... but as mentioned you´ll be repaid once achieved a good setup....

If you plan to use a left chain for the motor drive, while maintaining the right drive for pedals with derailleur and gears, (as the system is projected for), you don´t need a freewheeling crank at all, that´s one of the goods of the separated drive approach...the freewheel is at the motor output level....

The mongoose is a way better frame (for the conversion I mean), plently of space for the drive (and Cells?) under the downtube and no float brake issues....the possible assles I could see are:
- the section of the downtube where you would clamp the Davinci is not round ´cause of the gussetted weld
- The chainstay could interfere with the left chain.

Mostly you´ll have to chimie to obtain a straight line for the power (upper) motor chain part and sprung tension the return (lower). the more the power part of the chain pass close to the pivot level, the less chain growt you´ll have (and thus tensioning you´ll need)

Cheers

 

[stuntmanmike]

Saturday morning a package arrived at my home hand delivered by the US postal service.
In it was everything I'll need to get my project off the ground minus batteries.
1, The Davinci drive
2, Astro 3220 motor
3, Magura twist throttle already moded with Rc connections.
4, Castle Creations HV 160 esc.
5, Shumacher tech. Motor sprocket
First impressions are...WOW! The machining is top notch, which I expected from Shumacher Tech. I have wanted this kit for about 4 years and have read up on it extensively. I corresponded with Matt S. many times but never "pulled the trigger" so to speak. When this one came up on Ebay complete with all of this I knew I had to jump at it mainly because it was reasonably priced and complete. Maybe it was purchased by someone like me & too difficult to complete??
Anyway this is not going to be easy by any means and after looking at the drive I now know the Profile frame will be really hard to use for this. So I've decided to forgo that frame & choose another...Possibly my Nicolai UFO ST which is my primary free-ride bike or find another..But from the looks of the Nicolai the drive will work out well being that there are so many adjustment holes already there I can adapt to mount the drive unit.

 

[panurge]

You should decide the gearing and so figure the left sprocket diameter. than choose a frame where the chainstay does not interfere with the left motor chain coming from the freewheel output position of your choice/constrain.

 

[stuntmanmike]

Thank you Jules,
What would be the optimal gear ratio for this? I'm just trying to use what I have in stock w/o buying any new bikes or parts.. I have so much inventory, literally 10 bikes worth. If I buy anymore parts or bikes it will surely land me in divorce court... :wink:

 

[panurge]

Thank you Jules,
What would be the optimal gear ratio for this? I'm just trying to use what I have in stock w/o buying any new bikes or parts.. I have so much inventory, literally 10 bikes worth. If I buy anymore parts or bikes it will surely land me in divorce court... :wink:

EHEH! Do not say this to me....I'm in the same exact situation!!!!

What max speed you like? (best range could be between 50 and 70kph if you ask me, at 12s and assuming it is a 4t motor on a drive equipped with the torque limiter
Send a picture of the whole "new year cadeau" that could help to understand if something is missed and what is the actual ratio and setup.

 

[panurge]

A Single pivot bike with a boomerang or a straight monostyle swingarm could be the best geometry to work with depending on the output position, but the nicolai should work too if you find the right chain route...
Remember that you need the wider BB you could get, that's most likely the howitzer 148. but others should work. what you need is in fact an huge Q factor to clean the clutch protrusion with the crankarm, that is if you wanna keep the drive low. If you clamp the drive in a high position along the downtube,so that your cranks do not interfere with the clutch, than you could have nightmares to make an acceptable chain route/lenght/tension.
For the gearing it's crucial to know the motor turns and the actual primary reduction.

 

[stuntmanmike]

View attachment 1
I now have all of my Davinci drive parts a Castle ICE HV esc, Astro motor, Magura throttle & Lipo batteries. However all of my frame choices have been shot down by me or others here...So I'm at a crux...I've decided to go with my Nicolai UFO ST frame even though I love riding it without a motor. This frame has so many different shock mounting options on the down tube an effective drive/motor mount can be fabricated without too much effort, it may even look factory.
So I'll now strip the bike completely & begin & take photos as I go.

 

[recumpence]

I have frame mount clamps available if you need them.

Matt

 

[stuntmanmike]

I have frame mount clamps available if you need them.

Matt

Hey Matt,
Yeah for sure, what do they look like?