LightningRods mid drive kit

[stonezone]

I didn't get email notifications on any of your posts, Zack. Cheekybloke tipped me off that you were in here raising a ruckus.

I get a little needy sometimes... and I don't like to share

I haven't fitted a W-I freewheel to any of my threaded parts. I did write W-I before making the hubs and their engineer assured me that their spec of "1.37-24" is the same as the BSA standard of 1.375"-24 that I make all of my parts to conform to.

I know, you're thinking "But it doesn't FIT!" We need to check in with Foppel and his crew in Switzerland. I'm pretty sure that they have been running W-I freewheels on their LR mid drives. I don't know what's up here. Did SBP send you a left hand thread freewheel?

Here's a close up of the flange where the diameter reduces to about 30mm. It would be easy to turn down (for what) the adapter so it would fit, but how many threads does the aluminum need before it fails (in a fight, the FW threads win and come out unscathed).... you may be fine or you may be pedaling home
(hint hint - chromoly JS/FW adapter option for BB)

Here's the FW threaded in as far as it can go. I think it should work with the BB Crankarm without much shaving, but my threads are stripped so I couldn't test. I have a nice set of Jitsi cranks on their way, so i'll update

Here's them all together (avacado, no bananas). You will have to adjust your chainline but a small margin, it's not a clean swap:

The stock ISIS crankarm threads are roughly 57mm deep.
WBHDFW has 40mm of threads, then narrows out as the flange starts (narrows down to 30mm)
The standard FW has no flange and can thread as far as needed.
JS adapter has about 65mm of threads so bottoms out.

the HDFW is extremely well made and I want to run it on the BB side for sure (and eventually the JS). There is a ton of torque at the BB FW with the large drive sprocket and distance from the smaller sprocket as opposed to the drive side.

Hope that all made sense.

happy weekendings!

 

[LightningRods]

So the thread diameter and pitch is the same, like the W-I tech told me. There's just a flange in the threads on the W-I that causes the jackshaft hub (and the crank arm threads) to bottom out. This can be sorted out. I'd prefer not to have to come up with a W-I only design because not everyone is going to want $52 tacked onto the price of their mid drive.

 

[stonezone]

So the thread diameter and pitch is the same, like the W-I tech told me. There's just a flange in the threads on the W-I that causes the jackshaft hub (and the crank arm threads) to bottom out. This can be sorted out. I'd prefer not to have to come up with a W-I only design because not everyone is going to want $52 tacked onto the price of their mid drive.

You've got it.

http://0101.nccdn.net/1_5/300/188/182/Freewheel_Disassembly.pdf

 

[LightningRods]

That inside stop flange in the freewheel threads serves the same purpose as the outside flange on my alloy hub adapter. The hub can be made shorter and without the outside flange and it will work fine. The offset can also be adjusted at the same time. Looks like I need to heat up my VISA and buy some overpriced freewheels. $80. OUCH!

 

[John Bozi]

[youtube]2vIQVuOMWRs[/youtube]

 

[LightningRods]

Nice John! You're starting to let it off it's leash a bit.

The kit does seem to be noticeably noisier with the chain primary. No surprise since it's running 5x as fast as the secondary chain.

 

[eMTBHunter]

Great video, John. Can't wait to get mine and join the high power club.

 

[scorpionice]

That's a beast. Small Block is more than enough for me to climb and let the gravity pull me DH with additional power...just waiting for my upgraded components to get me back into dirt...cheers

 

[John Bozi]

I did enjoy 3 days of under 2.5kw absolutely smashing rough steep stuff. Unfortunately, weakest link will keep reappearing at high power, this time my lock ring and SS spacers gave in, I will fully investigate it tomorrow, but its just the sheer force even on a perfectly centred chain. I can add a bigger base to the sprocket but that will move the sprocket out of line..... and is there a tougher version of lock rings? they feel like such light thin bits of plastic or alu.... I know stonezone will say just weld the lot together.... Maybe this is something for Mike? Not just the hub but the whole body and sprocket as one big ass chunk...

Anyway thanks for the video comments, thought I would add a POV angle of my testing area at the back of my house. It's the same area as the last vid.

[youtube]m_oQMqMXIzw[/youtube]

When I've done these mountains it requires around 4kw with a hub motor and it will be on fire by the top and the controller will be just as bad. There is no way I could just keep smashing mountain after mountain like this. The little bafang could do it but at 10kmh it was boring.

 

[eMTBHunter]

That uphill run is amazing. Looks similar to some of what I see on the logging roads where I hunt. What sort of battery consumption do you see on a run like that?

 

[LightningRods]

When I've done these mountains it requires around 4kw with a hub motor and it will be on fire by the top and the controller will be just as bad. There is no way I could just keep smashing mountain after mountain like this. The little bafang could do it but at 10kmh it was boring.

There are two reasons that I use these motors: They're narrow for their power output and they shed heat amazingly well. When we run the big block hard up steep hills and it stays cool it's telling us that there is more power to be had. The limitation now, as John and others are finding out, is the bicycle drivetrain.

I'm trying three different approaches to solving for this final drive problem. Photos of one of the methods coming shortly.

 

[John Bozi]

That uphill run is amazing. Looks similar to some of what I see on the logging roads where I hunt. What sort of battery consumption do you see on a run like that?

On flat road I see about 1600watts, at the steepest continuous you can hear the motor slowing (I don't call bogging like for hubs because it is not overheating) it's always under 2500w. At time I want to up my amps and can by just pressing a few buttons on settings, but it is perfect power for now. It's perfectly controllable to hold WOT and the CA has a perfect slow ramp up....

As you could see that video was 10 minutes of continuous riding, from start to top of first mountain in about 3 minutes 1.5 AH @ 20s lipo, so double that to get home. Because it was Saturday (more walkers on popular trails) I chose not to do the full circuit which sees no repetition of the trails. It was a good call because toward the end of this video I started hearing the weird crunking sound and pedalled and a bit of very low power to the summit to glide home...

10 ah might not be enough some times but I can leave the house and have an explosive 30 minute ride and my wife won't even know I have gone. None of this putting you bike on your car and then driving to the trails, or riding 10 minutes and waiting for the hub motor to cool.

Have a couple of beers at home while I Recharge in 2 hours and do it again

Oh Mike posted before I finished writing. Look forward to the photos...

 

[LightningRods]

A client in Dubai ordered this gorgeous Foes Mutz full suspension fatty from Timberline Cycles in Colorado.

The owner of Timberline, Mike Vidovich, is obviously a very smart guy and seemed more open minded than most cycle shop owners about electric bikes. I asked him if he could put together a super tough 6 speed that had a gear range from 16T to 34T. He said "Sure!"

The gear clusters ride on two carriers with wide splines to spread the load out over the freehub. The 6/7 speed sprockets are much thicker than the 11 speed ones that came with the Foes.

Mike V. claims that this setup will take whatever we throw at it. What I like about these gears is that they work with a slick indexed shifter for quick shifts on the fly.

We'll see how strong this gear setup ends up being. I'm hoping that this will be our 2500-3000 watt freeride transmission. I don't think it will have the all out brute strength that track cogs in six bolt carriers have (a la Cheekybloke), but it will shift quicker and nicer.

 

[bowhunter29]

Mike, that looks like a great setup. If/when my N360 poops the bed, I'd like to give something like that a try.

Jeremy

 

[Mammalian04]

+1 though your other 2 options your are working on has peaked my curiosity.

When do you think the Timberline will be tested?

 

[Marin]

Very interested in that gear setup if it works in the Luna frame.

 

[LightningRods]

You could order up one of these gear sets from Timberline right now. They also do complete wheel builds. I'll be working on the custom mid drive for this bike for some time but I will try to throw a standard kit on it to see how the gears do.

This setup sadly won't work on the Luna with the 4" tires. Eric wanted to stay with a standard 135mm rear hub. The final drive chain will hit the tire before accessing the lower gears. The point of the 170mm or 190mm hubs on most fat bikes is to move the sprockets out so that there is a clean shot from the BB chainwheel to the inside sprocket. On my own Luna I'm thinking about going to 2.25" Schwalbe Big Ben road tires. I'll be going fast on pavement and fat bike tires are not the hot ticket for that anyway. With 2.25" tires and narrower rims this gear set would work.

 

[John Bozi]

I love the idea of gears, but call me a pessimist.

This will obviously work for for around 1.5kw, the question is pushing near 3kw that the big block can do continuously through a whole full pack of battery without overheating.

Chain wrap on 16t will not be enough the way derailleurs work only engaging half the teeth. 8t engaged is far from being able to handle 10-20 times human power the big block can dish out.

The thicker sprockets might be able to make up for the worse angle, but I am not sold until someone posts a video of this system holding up over 3kw over rough terrain with a chain wanting to jump and rub on anything it leans into.

I hope I can be proven wrong and this is the way forward.

What I would like to see is a strong single speed tensioner for heavy chains. These ones made for bicycles is not tough enough. The spring or whatever needs seriously more ability to hold tension and over long travel bikes.

I would even consider something thicker than bicycle chains for the drive train, but there's not more than a hair of space between the motor and wipperman 7e8 as it is now. Maybe a wider custom bb? but the problem goes back to a high sprung tensioning device.... around around it goes.

 

[Green Machine]

You could order up one of these gear sets from Timberline right now. They also do complete wheel builds. I'll be working on the custom mid drive for this bike for some time but I will try to throw a standard kit on it to see how the gears do.

This setup sadly won't work on the Luna with the 4" tires. Eric wanted to stay with a standard 135mm rear hub. The final drive chain will hit the tire before accessing the lower gears. The point of the 170mm or 190mm hubs on most fat bikes is to move the sprockets out so that there is a clean shot from the BB chainwheel to the inside sprocket. On my own Luna I'm thinking about going to 2.25" Schwalbe Big Ben road tires. I'll be going fast on pavement and fat bike tires are not the hot ticket for that anyway. With 2.25" tires and narrower rims this gear set would work.

Its right i chose to go with 135mm because i wanted my bike to be compatible with all the igh on the market (back then fat bike was not popular yet)

If you want to run fat tires you have to go with an igh like a nexus 3 speed and for my bike i would recommend with roller brake (about 130 dollars on ebay) or a nexus 8 or even a rohloff. i have run nuvincis before and they also work although not my favorite (heavy and shifter is like a toy)

 

[eMTBHunter]

Has anyone had any problem with stock rear axles/skewers?

 

[Warren]

Any bicycle quick release skewer that uses a soft piece of plastic as a bearing surface in the cam mechanism, like the top one in this shot

http://bikebro.com/Images/e2/quick_releases.gif

is worthless, evil garbage, and does not belong on any device, not even a seat post clamp.

 

[LightningRods]

Has anyone had any problem with stock rear axles/skewers?

I assume that you mean with the Luna. They're not quick release so this gets a bit confusing.

Eric has optional alloy adjusters for the rear axle that I feel are required for a powerful mid drive. The adjusters positively locate the rear axle and keep it from sliding forward under power. In his own testing with the Astro Flight drive he found that an adjuster was needed. That's the only problem that I know of.

I am making the first production run of Luna drives right now. All of the jackshaft housings and bearings are coming tomorrow. I'll have all of the laser cut parts back in about a week. All we need are the new 15mm diameter 4140 axles and the hubs to fit them. My machinist should be able to turn those pretty quick.

I'm going to contact everyone on the production list and see if spending another $50 for the upgrade to the W-I HD freewheel is unanimous.

 

[eMTBHunter]

I was actually thinking about the rear axle on any bike, and in particular the 170/177mm axles on many fat bikes. Just seems like a potential weak link given that I've had some minor issues with the axle shifting down or even completely out of the dropouts even under low gear pedal power with the QR9 skewers in the past.

Haven't had any problems since going to higher quality QRs like warren mentioned above, but now going to 10x the power with a big block and figuring that in my use I'll be in relatively low gears frequently, I can envision it being an issue. I'm wondering if I can adapt a torque arm from Grin, along with a different rear axle (maybe even just a 10mm stainless bolt) to beef up that area and provide more positive retention. Might have to fab up a couple different options. Not the most complicated thing in the world.

 

[LightningRods]

eMTBHunter you're going with a Luna aren't you? In addition to not using quick release the Luna dropout is horizontal like a motorcycle, not vertical. Apologies if you're not a Luna customer. It's impossible for me to keep people's forum handles and real names cross referenced. I haven't heard axle problems mentioned among mountain bike big block customers. It's usually the freehub or a low tooth count sprocket that acts up.

 

[eMTBHunter]

Sorry for the confusion, real name is Adam and I'm the one that was pestering you via email earlier this week because I changed my mind and moved up to a big block. Not going with a Luna currently (though they look amazing). I've picked up a 29+ on a pretty standard rigid fat bike frame that I'm putting my big block on.

Absolutely can't wait to get this kit. I was riding yesterday with my beater 29er with a trailer of gear and a treestand and I was wearing out. The best hunting is always found where most folks aren't willing to go and this kit is going to be a huge help in getting me to those places safely.

Here's what I was riding yesterday.

And one of the areas I was riding it.

This kit will be a game changer for me. Now I need Luna to get some 52v triangle packs back in stock. Hoping they offer a big pack with the 30q cells.