Klein Mantra Meets BHT!

If it is only the nipples that stripped when it failed (hehe nipples and stripping, I normally like those words together) you might be able to straighten and rebuild but a new wheel a much better option! Even just a cheapy to get you out there again. I would buy some body armor and a helmet if I were you too! Would be good to see your riding from a better vantage point for sure! Got any hills around you? I would like to see you do a speed run on that thing too please.

Urban trailblaze vid on last page. I'm running near topspeed at the start, then climb a short steepish hill. Towards the end it's wide open in a field. More to come. . .

Let me know the hill angle and length you want tested, I can at least find suitable pavement nearby. I can measure speed vs draw: ie 20, 25mph, wot.

Yes, the brass nipples are the weak point. They tend to break @ the eyelets. I suppose that's by design. Better than ruining eyelets or spokes I guess, although the spokes got a bit mangled.

No worries, I was just pissed cuz I had just trued the wheel, and the punishment didn't fit the crime so-to-speak. The poor wheel didn't deserve that when I was just walking the bike and a big stick got in there unnoticed.
I'd feel differently if I went off the trail and careened into a tree or whatnot. Then I would have 'earned' the failure lol.

Lol so you just munched it with a stick while walking with some throttle on?

yup. pretty brutal lol, a downside to high torque .

Hey, the failure looks like luke's death bike

But you have far less power than his motor.

Lol, and I call myself a 'nut' ! shame!

a few redone spokes and nipples. went to a backup knobby 2.1 rear tire and went to the mud!
cuts into the ground like a razor. Not favorable when you are going into public, (or the drive thru).

Guess I may have to rethink the rear 24" duro 2.25 bermmaster I was planning. We'll see.

It is time to tear down the rear of the bike.
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The right dropout is getting modified, and a little touchup paint. This extension is just mild steel, bolts @ 4 places, and weighs 4.5lbs. It asymetrically spreads the rear dropouts from 135 to 150mm while moving the axle back about 4".

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I wish it was lighter, but didn't feel like making it into swisscheese at the moment.



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I am making a new version of the dual fw hub. Triple bearing for 150-155mm d/o. Lacing it into a 24" alex32 rim to lower rake, bb height, and gearing.
I like the hozan threading machine, now I can easily build and repair wheels, reusing or modifying existing spokes.
[youtube]md8lmbyhELk[/youtube]

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I did this new hub adaptation almost completely by hand, but have learned solidworks and am working on a dmls printable or milled/cnc part.
The other bike build is also ongoing, hopefully it will offer a more available and easily modded and duplicatable frame.

An impromptu 3rd person vid of testing the new wheel and hub.

[youtube]NqKd5waJik0[/youtube]
Still gets to +35mph without pedaling, but the 10% reduction makes for a lot of responsiveness even in the last soc for the pack. I may lower the amps from 66/160a (ca shows 71a max). Pretty fun when it pulls the front off the ground 5-25/30mph though.

How does the 6kw bht compare to 6kw in a hub?

acceleration looks no different in the video, even though handling I am sure is different.

Nice green hole you found for testing....

thanks.

I literally have never ridden or even seen a highpowered hub or serial middrive in person.

Properly done you have the torque and gearless driving of a very hipowered (8-9kw?) non-cogging hub, @ half the motor and battery weight, which is distributed where you want.

The cost is highspeed. Or gear it for highspeed, and it's pretty much like that highpowered hub, except the weight is sprung. It would be a featherweight to compare it to a huge hub for a heavy 60-70mph bike though.
Imo this shines for a 30-40mph liteweight <offroad> bike.

I have no idea if you'd be happy with just the bht; tell me some hillclimb tests to try, to compare with your middrive. Although, it is guaranteed there is a trade off on this from a serial middrive's low speed effiency.
There is no magic bullet. Only the best utilization within your window of acceptiveness. For me, it's the simplest system for this performance.

PS, I kinda thought the acceleration was pretty dam good. Try watching second 56-58. (literally watch the time- the speed surprises me out of the corner of my eye.)

theres not question as I already mentioned of handling and high speed past 60kmh is not my thing. I prefer to spend this short life we have out a wheel chair and have someone wipe my ass if do survive an accident at that speed or higher.

I am pretty used to watching torque on video and there's no question you've got it. All I was saying was it doesn't look much more than my 20" wheel with the same amount of power. 6kw burst from a stand still would flip me on my ass too, and climb anything until traction digs a hole or heat builds up enough.

I would be happy with the bht if I had the custom building thing in my reach... I think..

It will be good to follow how long this set up lasts for you running as hard as I did my hub motor. I think I ran mine harder than most off road and it's off every road now that I broke the axle. I'll probably retire the whole bike to on road once I replace the hub motor.

However, the dream to have a bike that can climb steeper and faster than my last one has not ended, a new approach is needed for sure. Hence I am studying bht, revolt, astro etc. but I think I need to enter pit bike wheel territory to improve traction and longer lasting tyres.

enjoy your bike mate if I lived near you I'd be over for a test ride

I am pretty used to watching torque on video and there's no question you've got it. All I was saying was it doesn't look much more than my 20" wheel with the same amount of power. 6kw burst from a stand still would flip me on my ass too, and climb anything until traction digs a hole or heat builds up enough.

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You may be right. The easiest way to compare would be side by side with similar weights. On flat and on inclines.

Otherwise we could just compare numbers.
Say 5, 10,20,30 mph efficiencies and torque(acceleration vs weight) on flat, 10deg, 20deg, 30deg. Damn that sounds way to complicated lol.

An easy simple way to guess which is more efficient is to compare final speed at our gearing. Mine presently does 37mph with 20s and 66 battery amps. If yours if capable of 6kw, and is 'geared' for less than 37mph, it is likely to be very similar efficiency (waste heat) for the same weight. Am I thinking about that right?

I just ordered a china steel frame, it might be really easy to bolt up a mid motor- check it out! Eastgem.net http://endless-sphere.com/forums/viewtopic.php?f=3&t=70616 Maybe that could work for a nice enduro setup for you too? My goal is an lite HD enduro mid build.

I'm wishing I hadn't botherd with that steel frame. What a pita, and I'm pretty damn happy with this bike anyway!

Here's my first night ride video, hopefully it's entertaining, it's certainly pretty candid lol. (*runs into tree haha)

The 10$ ebay led is a nice light, but I need another or a flood beam for this kinda riding!

[youtube]yL0UbRLVyDk[/youtube]

You are funny dood, you remind me of myself. Talkiing to myself or should I say the camera when riding.

I've tried night recording too but it just is intrinsically not going to be better than day time recording, unless you have a reall need....

whats wrong with the china steel? happy with this enough then.... I guess.

Yeah, I had no idea the camera couldn't hear me good lol. It was fun, an adventure! I hit a tree min6 and found a sinkhole to china (or downunder!!) min8. The bike is great.

The steel frame will be nice, but not as much value as I thought. The damn seller made it sound like it would be shipped to my address and I just had to pay the import tax, which is near nothing on bike components. Turns out I am responsible for actually importing the damn thing. I could scream lol.

Made me realize how happy I really am with this bike. It really is great, I would just love more suspension honestly, and to try different geometry closer to a freeride/dh than xc. I could do all that on this, but it is a classic xc bike, so it's not logical to take it into that territory. I'm gonna enjoy it, but I want to remember that this just reaffirms my love for mountain biking and dirtbiking and cycling.

Let me know if you want any info on the dual fw hub I've done for yours. full 8spd cassette and hd fw for motor in a 155 d/o. It works excellent with 7spd trimmed cassette in the klein 150 d/o. I have the soldworks file for the new adapter, which I made myself on a mini lathe. Although you prob wouldn't need that unless running more than the 3kw+ that foppel is running on his LR's.

Actually here's the thread I started about my dual fw hub adapter. http://endless-sphere.com/forums/viewtopic.php?f=2&t=70771&p=1076226&hilit=jay%27s+dual+hub#p1076226


--- Oh on an unrelated note, I did my first long range/high speed test. It came out to something like 16mi/7ah 43mph top, 27.5mph avg. Negligable pedal input, somewhere around 500-1000ft total incline.
I get 3mi/ah if keeping it around 25 and pedal with it.

nutspecial said:

Just a little 'uban trailblazing'. Stil looking for the best completion of the circuit.

I want to upgrade the fork, and also the bar camera mount.

Eyeing a used/good shape 140mm marz single crown for xc/all mtn. Also have stuff on the way to build a 24" rear to lower rake, bb height, and gearing. In possession of a Duro bermaster 2.3. Sub $30 tire, still fairly aggressive, but a lot more rubber on the tread than the razorbacks. Cant wait to try it!

[youtube]fuWZanNQS7M[/youtube]

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nice build mate. Are you still on the original freewheel? I'm kinda surprised that its holding up to 6kw!!

Thanks snowy, yep it seems to have a significantly strong design. Still seems perfect after a lot of (600mi) hard riding. Definitely not 'highway' miles. The single sealed bearing has no play, and the pawls only have wear in the direction of freewheel spin action.

i wouldnt mind building something like this with a smallblock gng, not sure what reduction I would need however.

I learned from the other builds I listed on page1. They (I think?) learned from bzhwind. You can find much info on ratio's all thru our builds- that's the easy part, and very much adjustable imo.

Nothing much to report here, bike operating admirably, with a little evil side.
Eventually I'll do some surgery on the two weak 4s packs to drop to from 20s2p to 19s2p.
(I'm using 4x 4s and 4x 6s for that current config)
The 4s's drift horribly compared to the 6s's, but 2 of the cells are definitely weak and limiting available capacity.

I got that 'spartan' frame, and will do a similar build on it soon. Here it is with what I have- it looks great for a middirect drive bht imo, and the dropouts might not need extended, or the bht heavily modded- hopefully a frame bracket and easy bolt up. The frame is big though- 50" wheelbase. They are for sale on aliexpress for 615$ shipped to us, which is about what I ended up paying after the seller was very gracious about the kerfuffle.


Here's the tires I got from the same supplier. The 2.4 x24 are a great fit for the mantra and the yellow st3 bike. I'm thinking I'll try the wider 3" x24 in the new frame though, as there's plenty of room. eastgem/denzel pictured on an alex dm32 rim, measuring 2.25" total width

Me likes- about the same weight as the 2.35 bermmasters, but far more aggressive
We'll see how long they hold up, but 20-30$/tire isn't so bad.

this frame looks like a raptor copy. looking forward to see your build and how you like the frame.
with the BHT on the swingarm like you marked, do you think 24" wheels will fit?

Thanks, yep it appears 19/24's should fit with no mods.
You're right, the shape of that frame is very similar to raptor- at least the old style. I will learn more so I can compare the two fairly, but I doubt they are apples to apples.

Ps, I started a thread asking questions about bht, controller and battery for that upcoming build. Anything you guys can offer is appreciated, I still have to decide/buy all that stuff! https://endless-sphere.com/forums/viewtopic.php?f=2&t=73072

i'm now trying to convince myself into building BHT-based rig

suppose i have an 18s 30ah pack (probably samsung 29E or panasonic BE). 26" MTB rear wheel. what motor and wheel sprockets do i need to get 50kph on flat pavement?

BTW you're using #35 chain on the motor, right?

What voltage would that be? lipo 18s (69-74v) did 30mph+ on 5/1 reduction & 26"wheel.
#35 chain/sprockets, 11t to 55t -ALOT of torque

Went to 80v (20s) and 5.45/1 (down to 50t rear) for ~42mph on 26" and still up to 38mph on the new 24" wheel.
Still p l e n t y of torque! I imagine the samsung in 30ah should easily deliver ~70a, so you would have a really powerful ride with it, for lightweight or a heavy ride