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Slo Ride

It would seem my motor has gone on round the world tour and now it's back in Greece. They claim to have reshipped it and complained about they had to pay postage a second time because they sent it wrong the first time. I'm beginning to worry it may never show...
 
Goat makes a 96 volt 15000 watt e dirt bike for $5,000 it does 65 mph. I would not bother building something that would probably cost more than this.
 
It would seem my motor has gone on round the world tour and now it's back in Greece. They claim to have reshipped it and complained about they had to pay postage a second time because they sent it wrong the first time. I'm beginning to worry it may never show...
If the Lehner dosen't make it, Lightning rods sells some some nice honken' big motors:

Lightning Rods

I have a couple Toppower TP128, which is the equivalent to the LR XXL Motor:

XXL Motor

Serious motors.|
IMG_20231018_131924116.jpg
 
Goat makes a 96 volt 15000 watt e dirt bike for $5,000 it does 65 mph. I would not bother building something that would probably cost more than this.
Some of us enjoy the process of building our own! I have done a cost workup at about 3K to 4k total depending on the battery with me doing the build but does not account labor costs since that's my hobby! Of course that's provided the motor I bought shows up for the price I paid. The largest problem I foresee at this time is cramming enough battery in to handle the 24kw nominal current load!
 
If the Lehner dosen't make it, Lightning rods sells some some nice honken' big motors:

Lightning Rods

I have a couple Toppower TP128, which is the equivalent to the LR XXL Motor:

XXL Motor

Serious motors.|
IMG_20231018_131924116.jpg
Looks like a similar motor but I'm praying the one I ordered makes it. Yeah it did cost a bit more but it's also rated as a 100,000 hour motor and it only weighs 4.2lbs.
 
Just sent an email to Grin to see if they would be willing to build me a rear wheel for this project bike. For some unknown reason I have my doubts about hooking a 24kw motor to a standard 16x4 bike wheel! Anyone know of any other places that might help or be less expensive?
 
Folks who know what they're doing will tell you no. Folks who don't care will take your money.
I just wish I knew a formula to compare the torque of a 20,000rpm 24kw / 32hp electric motor to a 10,000rpm 37kw / 50hp gas engine! My gut instinct says the 24kw electric motor will have better acceleration than a 50hp gas motor. But I just don't know! The electric bike will likely weigh about 65% of the weight of the gas motorcycle I'm using as a comparison.
 
I just wish I knew a formula to compare the torque of a 20,000rpm 24kw / 32hp electric motor to a 10,000rpm 37kw / 50hp gas engine! My gut instinct says the 24kw electric motor will have better acceleration than a 50hp gas motor. But I just don't know! The electric bike will likely weigh about 65% of the weight of the gas motorcycle I'm using as a comparison.
Consider that the poison motor will make max torque at 1/2 to 2/3 of max power RPM, and the electric motor will make max torque at zero RPM. So the more powerful poison motor, if correctly geared, will have a higher top speed. But the electric motor will hustle faster off the line.
 
That's exactly what I'm thinking except the top end speed will be almost identical if and only if my math is correct. @Chalo

True @gromike I will not have the extended speed ability of the E-motos. Believe it or not I expect to ride bicycle speeds 98% of the time. I just like the ability to go fast when I want too! There are lots of private places around here I can open it up when I get that feeling, including a private airstrip.
 
That's exactly what I'm thinking except the top end speed will be almost identical if and only if my math is correct.
There's really not much math needed to see that it's quite hard for a 24kW peak power vehicle to match the top speed of a 37kW one. The weight has negligible impact on top speed, aerodynamics are much more important.
Believe it or not I expect to ride bicycle speeds 98% of the time.
I don't believe it for a second because riding a motorcycle at bicycle speeds is just completely unnatural. Once an open road segment happens I bet you'll just ride it accordingly to its capabilities. And it'll be very inefficient at slow speeds, too.

Plus remember what I said about suspension. You wanted a vehicle that goes up to 160km/h. Suspension setup for such speeds feels awful at 30km/h because the compression forces don't even start to bend the damping shims and it feels like it has no suspension at all. That's another reason why riding a sport bike in a city is a dumb idea.

Now, I know that there's a difference between a sustained cruise at 160 and an absolute maximum rating of 160 in perfect conditions (more in line with the 24kW power), and then we're looking at an equivalent of something like a 250cc bike. That could conceivably go that fast just to show it could, but you'd otherwise almost never use it at such speeds. Those are optimized for speeds in the range of 70-90 - much more reasonable for this power train, but still far more than any bicycle. The issue with electric powertrains is that they don't work like gas engines and they reach their peak efficiency close to their top speed, so if you gear it unnecessarily high, you'd be losing a lot of acceleration and range.

Long story short: a fast bike ridden slow will be harsh and inefficient. A slow bike ridden fast will be sketchy and potentially unsafe. Anything that tries to bridge those two will be a compromise worse than a vehicle designed optimally for its target use.
 
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Most of the many 250cc bikes I rode struggled hard to go 90mph and were more comfortable at 20-60mph much like I expect this to be. I may not have ridden bicycles for 40 years but I owned and rode a LOT of MCs on road off road and on tracks. I also daily drove many things that were as comfortable at 175mph as they were at 50mph. Then there's my old backyard built Z28 that once ran an 8.73 in the quarter mile and regularly ran 9's and 10's yet I drove it on the road everyday and never once in twenty years got stopped for speeding. The nasty bike I rode a few times was an old custom Harley with an air shifter, now that truly was a bit much on the street. My point being just because you can fly at any time doesn't mean you have too!

Grin already got back to me and they suggested an MC wheel...
 
Alright I finally figured out how to get the shipping info translated to english. My motor is in America and is ready for release from customs. Looks like it should be here next week! I will rest a lot easier once it's in hand!
 
I know I said I wasn't going to order anymore parts for the bike until the motor got here. I lied, although the motor is in Virginia according to USPS. There has been a NOS rear wheel for sale on E-bay for 50% of new that I've been wanting to order but had been holding off on. This morning I noticed it was in two other carts so I jumped and ordered it. Gotta save them pennies when you can! That's one more piece of the puzzle down. Still lots of pieces to go...

The downside to this wheel is it's color, it's mustard yellow! YUCK!!! That means I will have to try and remove the paint and polish the aluminum or go lame and paint it black.

My daughter just picked the motor up from the PO box.
 
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Hi guys looking for a bit of help.
This is the motor I'm using. Torqstar 3 (7050) - Lehner Motoren Technik I'd like to be able to run with my 51.2V LifePO4 105AH battery until I can save up for a 72-96 volt L-ion 100AH battery at minimum. I think 96 volts would be ideal but not positive. I'm wanting to get every ounce of power I can out of this build!
These are the parts I'm hoping to find in kit form and I may have overlooked things.

controller 72-96V 250-500 amps one that can run on my excysting 51.2V battery (NOTE: If I have to I can start with a lower powered controller but ONLY if I can still use every thing else when I move up to a larger controller
PAS
throttle
display
wiring harness
regen braking
Key switch lights, horn etc.

I'd also like to use DYisland hyd. disk brakes with at least 180mm rotors, larger if I can find them. I have the 160mm version of these brakes the bike I have now and they are awesome!

Let me know if you see anything I've missed and thanks again if you can help!
 
Just sent an email to Grin to see if they would be willing to build me a rear wheel for this project bike. For some unknown reason I have my doubts about hooking a 24kw motor to a standard 16x4 bike wheel! Anyone know of any other places that might help or be less expensive?
Do NOT do this. Anyone who agrees to build a 24kw motor into a bicycle rim doesn’t know what they’re doing. If you think it’s the right setup, then why do you need someone to build it for you at all?

Go with 17” moped rims. 1.4-1.85 inside width. Or use 17” sportbike rims and run them with tubeless tires. Much safer and lots of tire choices.
 
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Or use 17” sportbike rims and run them with tubeless tires.
17" rear tends to be quite wide, but a 19/18 or 21/18 setup would still provide a lot of great tyre choices. It's no problem to seal a spoke rim for mc tubeless tyres. The bigger issue is making the whole thing cost effective - you can buy a complete, used MX wheel for about $100-120, including a brake rotor, tube tyre, sometimes with functioning bearings. If you start building from parts, that won't even buy a rim.

We still haven't heard a weight target from the OP, but assuming a realistic (for 24kW) 100kg, those wheels will fit right in.
None, I said it before and I'll say it again, there's no reasonable way to have pedal power as well as a 160km/h max speed target and 24kW peak power. If you want to pedal it, you should relax those requirements, otherwise it's completely pointless, you might as well push it by hand.
I like my cheap cable throttle for various reasons, check out my #1 thread for the mods on it. Sourced on Aliexpress. If you can't spare the space then something with a hall sensor on the bars will work, but a Surron throttle is awkwardly short and might be too aggressive.
Strictly depends on the controller you get. If you go with something from SiaEcoSys (Votol/Fardriver), you can use one of their displays (or build from my designs, lol). If you go with VESC, then you should get something for VESC etc.
wiring harness
I've just done some research which I haven't posted yet, but preliminary results: 18AWG multicore cable is fine up until 4 wires per cable, more or less. I bought a 7-way variant for the multi-way controller and that thing is pretty freaking thick, I think 20AWG would work better for so many wires. I wrap them in a "mesh net" cable wrap that rolls out on one end. It's not that cheap but works very well, is reusable, and you can let the wires poke out in the middle. Secure the ends with 4:1 heatshrink and you have a professional harness.

Oh, and I'm planning on replacing cheap controller connectors with waterproof Sumitomo clones. Everything sourced on Aliexpress.

Key switch lights, horn etc.
The only thing to keep in mind here is that you'll likely want to run a 12V line for lights and horn, so you'll need a reasonable DCDC converter that can handle 100+V of your battery. A good wiring harness will help with routing all that, I'd also recommend a nice dedicated distribution/fuse box.
180mm rotors
For 100kg, you'll need at the very least 240mm up front. Prefferrably with a motocross dual-piston caliper. They're pretty light and their performance is on another level from bicycle components, and you can buy them either used from old bikes or new on Ali as well, the clones seem to be of reasonable quality and cost almost nothing.
Let me know if you see anything I've missed
Mostly you should revise your requirements and state a clear weight target. It's okay to wish for a super light, super fast, and super powerful machine, but laws of physics can't be negotiated with.
 
17" rear tends to be quite wide, but a 19/18 or 21/18 setup would still provide a lot of great tyre choices. It's no problem to seal a spoke rim for mc tubeless tyres. The bigger issue is making the whole thing cost effective - you can buy a complete, used MX wheel for about $100-120, including a brake rotor, tube tyre, sometimes with functioning bearings. If you start building from parts, that won't even buy a rim.
No dude, you do not go down rabbit holes like sealing spoke rims on threads like this where it’s important OP simply STARTS building. Usually when I start a build thread half the frame, or at the very least the configuration has been established, with major parts bought.

With OPs desired numbers he’s clearly going to build a Motorcycle. Talking 96v 100ah, that’s a 100lb battery right there. No, 21/19 is NOT the answer… mag rims are… and so is starting with a motorcycle frame.

OP you need to decide on what you actually want and do more research than posts. I have a frame with CA title for sale which I’ll post in the sale section after this. It’s perfect for a build like this.
 
Yeah I am trying to do the impossible again! I go down this type rabbit hole every so often building really strange crap. Thanks for the pointers it's very helpful.

I am on the other side of the continent in Virginia.
 
Yeah I am trying to do the impossible again! I go down this type rabbit hole every so often building really strange crap. Thanks for the pointers it's very helpful.

I am on the other side of the continent in Virginia.
Well you have to decide exactly what you want. I like bikes under 200lbs and 35mph average speed (actually under 150lbs, but that’s a hard number to hit). A large battery is good but to keep the weight down something that charges fast is more desirable. You can generally spec for 100lbs/kwh for pouches and about 120lbs/kwh with round cells. I would do 90 mile day trips in a total of 4 hours with two stops for charging to full at 45min each at 4kw charge speed. With a 4kwh battery this is completely doable and a 4kwh batt only weighs 40lbs. With 24kw that’s pretty much the bike you’ll build.

That bike you just linked is a BICYCLE that weighs around 80lbs. It probably has a 1kwh batt so in a 96v that would be a 10ah. More research and decide exactly what you want. Post it here:

Total weight
Top speed
Average speed
Terrain
Budget
Your experience level (metal fabrication? Build your own batts? Past builds?)
Range
Charge station availability
 
Yea you’ve got to decide exactly what you want. Threads like this are pretty much asking for people to spend (waste) a bunch of time talking about possible builds, but with you linking bicycles and talking 100ah batts it’s an obvious disconnect. I won’t be responding again cause this thread is going nowhere, but I’m a guy can build a frame for you with major components ready to install once you decide.
 
Thanks again guys! I'll likely build the frame myself or buy something similar to the chopper I posted and just go with it, I'm hard headed like that! lmao

Back in the early 90's they said I couldn't build a ten second street car so I built an 8 second street car to prove them wrong then drove it on the street nightly and raced it three times a week for nearly 20 years!

Once I get something built I'll post pics until then have a good ride!
 
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