72V 3000W Cyclone Electric and Gas Generator Build (SBP kit) - Three Phase Dev

[Frogslayer]

Right, whether your bucking the wind or the fairing is, the wind must be bucked.

 

[bakaneko]

Sorry for the spam and delay. I've been busy with new jobs and school. You know you just don't want to do anything after a long day of work and just be a vegetable in front of the TV or computer. But anyway, I would like to say I hate chains, chains, chains. Again, since I am so busy or tired, I hate working on my bike to adjust the chain that is why I bought an electric motor to not do that... Hub motor probably better for real lazy people that just dont want to be bother.

And, onto the update, I will buy the major components tonight - 2 stroke 25cc engine, 400-500W generator, step up converter and get moving to finish this build. I do have a few other things I want to talk about regarding electric bikes in the cold and what not but I'll save that for later. Here is a rough schematic of what I will do. Let me know if you see a major flaw.

Based on work from others and tutorial from Creative Channel on YouTube. Also, if that step up from 20-24V to 83V is too much I will swap out the bike to my 36V 500W rear hub motor to test and perfect and then later switch to a 52V system on a 1000-1500W hub motor.

https://motorbicycling.com/threads/electric-bike-with-generator-range-extender.58823/

 

[The_Aleman]

I've been throwing this idea around in my head for years - many of prolly have - having easy gas refueling and wonderful elec torque all in one, easily replicable from home using relatively inexpensive parts! Basically a generator on a bicycle.

3D-printable microturbines aren't quite here yet LOL... But we have lots of great small engines, keep up the good work!

 

[bakaneko]

I've been throwing this idea around in my head for years - many of prolly have - having easy gas refueling and wonderful elec torque all in one, easily replicable from home using relatively inexpensive parts! Basically a generator on a bicycle.

3D-printable microturbines aren't quite here yet LOL... But we have lots of great small engines, keep up the good work!

Thank you for the pep talk. I will try to do my best to make this a reality and test it out in full (10, 20, 40, 60, 80, 100, 200 miles with varying speeds). Probably a ton of post here but I will recap my vision for this, which is probably very much inline with yours. I want to combine the reliability or an electric hub motor (mid drive in my case) with a gas generator running on a high rev and a decent size cheap Li-ion battery (1kwH+). The pricing should be about a high end gas bike setup; maybe somewhere around $600-700 without the bike for a 1000W system that does 30-33 mph max, 22-25 cruise.

I think the key is to limit the generator to a medium to high rev and not over tax it otherwise the reliability would be no different than a traditional gas bike. I've seen a very few builds like this being done but I think the problem in those builds is the battery is too small or an SLA. I want to focus this on the battery first and then generator second. But, who knows, I am kinda scared because while I see the few threads about it here and there over the last 10 years I did not see extensive and long term YouTube videos about such a build and riding. I have a YouTube channel (will get better camera soon...) I want to document it fully even if it is a total failure or a key assumption/goal needs to be changed...

 

[bakaneko]

Okay, so I really need to slow down; I made a couple of bad assumptions, which I followed up and caught. I did not buy the parts on Sunday but just now. Here is where I fooked up.

#1 - My worry was right. According to the vendor, but he said that a 18-22V cannot be step up to 83V, which was my concern. I think what would happen in this case is that you just get a lot of heat and huge inefficiencies which would eventually make the converter go boom. But, he said I can step up 18-22V to 41-43V... And, I also saw a video review of the same converter on Amazon where a guy steps up 14V to 48V for his ebike batteries. So... I guess I would be changing the battery setup back to 36V (thank goodness for my modular battery setup) and basically cutting my power potential in half. I could try to test it at 83V and assume mebe the vendor was just being too safe but I dunno... At 36V nominal, it means I wont be at 3000W max continuous but at 1500W max continuous or closer to 1000-1200W, which is a little over 30 mph. Still decent but yeah I won't attempt to hit 50 mph now when I'm back at 36V and it is too cold now to even attempt 50 mph at 72V. Much later, I can try running two step up converters in series to go from 20V to 42V to 83V...

#2 - The video I linked and am reference uses a 33cc 2-stroke engine that had 4 mount holes at the bottom of the engine block. I assumed this was the same for 25cc. Nope, there are no engine mount holes on the bottom. I went to the hardware store (work there) and had a real good look and inspection of the 25cc. I think I can use the bottom front shaft screw hole and the back gas two screw holes as locators. I don't think they can serve as mounts as I think they are not engine block holes especially the two in the back, which just go to hard plastic. So, I will need to provide an additional clamp or straps to get it on the plate securely and resist vibrations.

In terms of the plan, Imma do the following over the next month or so so its ready to roll in mid March just in time for spring break where I can take off from work and if I am confident go on an epic tour.

1. Test the 25cc motor operation - start up, choke, idle, rev ranges
2. Assemble the generator setup
3. Test the converter for voltage ranges, current, and memory (turn it off)
4. Assemble the mounting plate on bike
5. Test the generator and ebike only (no battery); make sure it runs
6. Test entire system together for functionality
7. Route generator throttle line to unused gear changer on handle bar and check power levels. This might not work; the throttle play in videos for the 25cc looks real twitchy. Ideally, I like to be able to set the generator power level from the handle bars and not have to stop and change the idle.

 

[bakaneko]

ultimate cringe video of gas generator build plan

 

[bakaneko]

Parts are here. The 500W generator is huge; total weight is about 15lbs I estimate. Man I hope there isnt going to be a stalling issue from the small 25cc motor. The 1500W converter is much larger than expected too. It has a huge heat sink and fan. And, it is so cold here. I might fire up the engine wed-thur this week if not it will be the following weekend. It is gonna be a cold one for a while... sigh

 

[bike4life]

Parts are here. The 500W generator is huge; total weight is about 15lbs I estimate. Man I hope there isnt going to be a stalling issue from the small 25cc motor. The 1500W converter is much larger than expected too. It has a huge heat sink and fan. And, it is so cold here. I might fire up the engine wed-thur this week if not it will be the following weekend. It is gonna be a cold one for a while... sigh

Isn’t easiest thing to do is buy hf tailgater generator 90 bucks and puts out 700 run 900 peak watt then full bridge rectifier to dc

 

[bakaneko]

Isn’t easiest thing to do is buy hf tailgater generator 90 bucks and puts out 700 run 900 peak watt then full bridge rectifier to dc

But, where is the fun in that. I am all keen on that idea and if the Powerhouse 500 was still available I do that. But, the HF Tailgater generator is 16x19x15. The tall 800-900W 4 cycle ones are 17x9x14 and both are about 35 lbs. The one I am making is about 6x8 (only 25cc)x14 and about 20lbs. And, I might change the linkage it can get down to like 10-12 long. That being said, I've been tinkering with it disastrously.

I got the engine to run and was just about to get it right to the point where I can start really testing it with minimal vibrations then the stupid pull string breaks. The design of the stupid thing requires me to remove almost everything to fix the pull start string including the clutch bell driver, which requires a #25 torx head that I dont have. So, I ordered it and it is on its way. I did notice that the YT video I am following seems to not use a clutch so when that #25 torx arrives I might just remove the entire clutch and just use the drive shaft to connect to the generator. I was afraid that the 25cc engine would not have enough power to start the generator and need a clutch to not stall but I will test it without the clutch.

This might take more time than I anticipated... Nvm, the YT video does use a clutch. Yeah, so I had to give the small 25cc a push on the coupling for it to get going. There isn't enough raw power for it to spin the generator from 0 RPM. LOL

 

[The_Aleman]

Thanks for the update! Man, if this was easy we would have seen a lot more of it LOL

Keep it up!