Left side freewheel sprocket adaptor

[panurge]

That's very interesting. So, seems you designed a ratcheting mech and supported it by that bearing, nice.
I would get one for sure if reasonably priced.

As per Matt advice, the efficiency would be substantially improved. The concern is that with a powerful motor with a huge reduction (although a single stage) the torque is a lot: @7+ Nm peaks, my astro after a 19:1 reduction is capable to deliver roughly 140 Nm to the wheel.
There is also the lash question: the more radial play, the more you will feel a delay in the engagement, the more the ratchet impact will be high, generating a bigger stress than the torque applied itself, this should be taken in mind, because of the delay, that's not a good thing, and mostly to not have a mech that withstands the requested torque, once engaged, but could fail soon due to the lash impacts.

 

[nutnspecial]

I can attest the white HD freewheel has held up to 2yrs of hammering on my right side rear. I have averaged about 6kw and have more recently hit it with 7.5kw. I have no idea what the 11lb bht motor is transmitting to the rear, but it's alot- way more than enough for single reduction 240lb gvr ride geared 30-40mph. I like to say 'it will climb a tree, or put you through one'
Anyway, that 3 paw design works great, and the similar bearing is still fine.

And I don't care how large your front sprocket is or how nice the chain, ANY chain is gonna rob more energy than a FW and make more noise- not to mention it will wear faster if always live. I recently changed out my sprockets and the #35 components are sawtoothed and beat to hell. Meanwhile freewheel is good.

Also, having done right side paralleled with pedals, I wouldn't do left side with a disc brake involved. I can't imagine the pita it would be to upkeep the driveline and keep the brake clean and viable. Imo an offroad bike isn't very good just for fair weather, which means frequent chain maintenance. Perhaps a jackshaft setup would be nice to tie in the pedal gears to go direct to right-rear, and would much easier allow to keep a 135mm d/o if desired, but a true parallel right side has benefits too and I'm happy with it.

My adapter and mods are coarse diy, and I would love a properly purpose built and milled setup. This could all be done most easily with a custom made FW similar to the white HD. It would thread on right side of a flipflop/fixie threaded hub sandwiching a center '6000' type bearing between it and the bearing race for extra strenth. The outside of the FW would have the 10t internally threaded cog to accept a standard freehub w/cassette and final bearing.
The hub could be made custom with disc mount (instead of threads) on left, or it could be a diy with 6 hole threaded disc adapter like I did.

Let me know if you want more info Rouckie, I even have a drawing with White Industries for the custom FW, but never went ahead because they wanted a run of 100pcs min. Technically just the driver would need to be done custom. Mine uses a diy modded Hd Fw and a custom aluminum 10t adapter. Here it is testing, https://www.youtube.com/watch?v=NqKd5waJik0 I've since updated and upped the power and speed a little. I plan to shoot a new vid tonight or tomorrow. Again, I definitely wouldn't do a live driveline or a left side drive w/disc unless absolutely necessary.

 

[panurge]

well, your double FW setup is awesome, nutspecial, and sure is a cool option for parallel drives, but, in regard to the topic, and the reliability and torque/lash survival, remember you're using one of the best freewheel on the whole world market. That's for sure one of the keys of your long lasting results, as well as the lack of pedal chain growth in your rear, that sure helps to avoid pedal chain skips and fail (that could be dangerous when two chain are so close), but that is however achieved with geometry compromises not acceptable for a long travel suspension made with gravity/landing purposes.

If Rouckie wiil be able to engineering and realize at reasonable cost a precision and strong freewheel mech like the WI, than I guess his setup will sell well among us and withstands all the abuses....

That said having a live chain, although not wanted, is not that terrible, and I have 12.000 Km made with a LH drive that way. I've a 160mm rear disc that's half the Dia of the 61t track sprocket I'm driving on the 6 bolt mount. mud, rain (with motor guards) snow, bumps, jumps....I've seen everything with that setup. There's no way lube or anything from the left drive will affect the disc working. LH with live chains It is just another option, I would say, probably, the most used, and well proven to be reliable and straight for parallel drives.
There are also bearing factors that justify to have an LH drive with a rear Disc hub with freebody....
Pivot bearings and wheel bearings are the true stressed parts that needs a closer scheduled maintenance/replacement in my bike, other than the Motor chain, after the conversion. I'm still using the same 61t sprocket, the same ENO (drive output) and belt/pulleys for the suspended part of the drive.

 

[nutnspecial]

There's no way lube or anything from the left drive will affect the disc working.

That's great to know- maybe I'm way too sloppy but my whole right side is covered with greasy grime after a few seasons lol. I don't quite follow on geometry affecting RH more than LH parallel, but that's not the point anyway- I just wanted to note that the design of the Wh Hd Fw is what to mimic for good reliability. (And also share my hardon for getting a simple HD one piece fw/adapter, preferably that threads on and carries motor power and cassette.) I guess LH would be fine too.

 

[panurge]

I don't quite follow on geometry affecting RH more than LH parallel, but that's not the point anyway- I just wanted to note that the design of the Wh Hd Fw is what to mimic for good reliability.

Although I'm now running a narrow wide setup and clutch tensioner pedal side, I still have occasional problems with that chain rather than with the LH one. As your fear about greasing rotor/caliper isn't confirmed by my experience (and I clean and maintain all my bikes quite regularly), I guess also my fear about having 2 chains running so close, even independents, isn't justified; but it's what, at least conceptually, has stopped me to seek that route at the beginning of my conversion; other factors are to avoid more stress in the RH bearing assembly, the mentioned lash problems, aesthetics and of course the readily available parts and ease of the LH option. Were your RH setup made at that time, I would have taken it in much more consideration.

So Rouckie, I think there will be good interest in your unit, sure from me. If the mech isn't a patent pending or secret design, could be nice to have more details about it....

Subscribed!

 

[Rouckie]

Hello Panurge,

It is a pretty normal spring and pawl system, only adjusted to the form factor we need.

Probably pictures of the unit on the bike this evening (still printed version). I had to make some modifications to the ratcheting system.

 

[nutnspecial]

So Rouckie, I think there will be good interest in your unit

Totally agree. There's the raptor LH kit version LR is selling I think- a FW would compliment it very nicely, or for any LH builds. Plus there's no reason Rouckie couldn't expand to a RH too.
Rouckie I'm also looking forward to what you are making man, kudos for taking the initiative and doing the work!!!

Just fyi for pedal chain growth- totally right that can be an issue, although I've never had one derail off the top of cassette or inside the cassette to the point it hit moto chain. Mine is URT so there's no growth, and you can get 0 growth with a concentric bb/pivot or swingarm mounted bb too for bigger travel susp. I did find I needed wider pedal tread to do LH than RH.

 

[Rouckie]

https://youtu.be/wh1Nu2IwFHw

 

[panurge]

Cool! I'm in to test one! we're reasonably close, at least in the endless sphere scale .
Seems not made with a high number of ratchets but with deep ones....could be effective.
Simplicity, very high material quality and precision are the keys to keep the clik count relatively low (a good balance between lash and drag) still having a strong and uniform engagement, exactly like the WI ENO.

 

[Rouckie]

First test today. It was running great with the wheel in the air. I started loading the wheel with the rear brake. When I almost reached full throttle the printed housing just broke open. I assume it very shortly survived something like 30-40 Nm.
Oh well, at least I had 2 minutes or so of fun.
On the positive side, now I need to make the machined version immediately.

 

[Rouckie]

Ok, first machined version is ready. Too late to test it now, but it is looking good.
I hope I can do a first test tomorrow.

 

[Rouckie]

First test today. Just a quick ride up and down the street. It freewheels very nicely.
One thing I noticed is that the engagement is harsh from time to time (as panurge already indicated). This might be a problem for durability, and for sure does not feel nice.

Does somebody now if the Phaserunner has the option to limit the acceleration rate, without limiting the phase current? I know some industrial controllers have this option. This would make the feeling of engagement much better, without negative side.

 

[ferret]

The Cycle Analyst as these capabilities.

 

[Rouckie]

The phaserunner has this option as well. Although I don't really understand what it means. The parameter is called "limit speed ramp time". I have it set to 30 000 msec, approximately the max value, but it still is not very slow. Does it need another parameter to work well?

Anyway, tomorrow I will open the unit for review before the first real testride. I will also put up some pictures.

 

[Rouckie]

First test run today. It was very muddy. Freewheel worked great. Opened her up after washing, I need to work out the sealing better for these extreme conditions. It was still working perfectly at the end of the ride, but the high pressure washer wasn't the best idea. a bit of cleaning and regrease: good as new

some pics, new and after the mud.









View attachment 1

 

[bionicon]

Nice, btw is that a beltdrive? do you have a picture of the complete settup?...how much kw do you run true it?

 

[mike_o]

Also my question: Is that a belt drive? Thats my idea :wink:

I'm looking into doing a low power, parallel, free wheeling drive with a 6 or 10mm timing belt, using a 300-400W low-kv brushless RC motor. I figure a 1:20 reduction is required to maintain a reasonable bending radius on the motor pully, 16-18T should be minimum, requiring a 45-50cm diameter pulley for the wheel. I did consider making this, rear pulley out of several 3D printed sections bolting them on to an alu adaptor disc...

Anybody else with that idea?

Very interested in the nice project!

thanks

 

[Rouckie]

Hello,

did a new test run yesterday. I'm running only 44Nm through it for now (put too much effort in it to destroy it the first couple runs ). I also added a torque ramp of 1 sec in the controller. So from 0 to full torque takes 1 second. Engagement is smooth now.
It is a real pleasure to ride with this freewheel added to my setup!

as for the questions on my setup: indeed, it is a belt drive. I'm putting 1.5kW through it. I will post some pictures later on.

Ps: working on version 2 of the freewheel (finding solution to have better engagement without torque ramp).

greetings,
Roel

 

[tomarth]

Just checking in...how are you getting on with the freewheel, any updates?

 

[Rouckie]

Hello,

I'm still using this one. working great.

 

[tomarth]

Great to hear Rouckie
Do you think it'll handle a heavy torque? and are you going to bother with a version 2?

 

[Rouckie]

I'm now working on a more powerfull bike.
Aiming for 120Nm at the rear wheel. I believe I will use a freewheel on the jackshaft.That freewheel be probably homemade as well.
as for the rear wheel freewheel, maybe for a next project, if I can find a motor that can deliver enough torque so I can use only one reduction. For now, I will need 2 reductions to get to the 120Nm.

 

[tomarth]

I'm trying to figure out my first build...
Originally I was going for a freewheel on the left which lead me to your clever creation...

I'm basing my build on an Giant Stiletto (chopper/cruiser) which has a built in jackshaft and huge frame space to build in.
With the jackshaft I could drive a rear sprocket on the left or right (I will probably put the freewheel on the jackshaft).
I've lots of options, but little experience or knowledge!

Just out of interest, what motor and other bits are you using or planning to use on your new more powerful build?

cheers,
Tom

 

[Rouckie]

Or 2 times 6374 motor, or 1 time 8074

 

[Andrewol]

Hello Rouckie,
Could you please share a building info of your adapter with FW? I would like to make conversion of my bike as well.
Cheers.