Finished building my 25mph Ebike - Page 4 - RC-Monster Forums

snellemin · 05.09.2011, 01:52 AM

Added 30A fuses to both the positive and negative wire. Swapped out the deans for 5mm bullet connectors for the ease of using the precharge resistors. I use dual 1W 100Ohms resistors. Zero sparks now with 20S lipo. My setup doesn't look stealth anymore though. I had to choice as it was 95F today and there is no way the speed controller would keep it's head cool in the closed bag.

Overdriven · 05.09.2011, 05:51 PM

Thats a pretty sick setup you have there! I've ridden alot of contraptions at various speeds and can agree it gets kinda scary above 30mph on a bike!

snellemin · 05.09.2011, 09:42 PM

Quote:

Originally Posted by Overdriven

Thats a pretty sick setup you have there! I've ridden alot of contraptions at various speeds and can agree it gets kinda scary above 30mph on a bike!

Thanks man.

I've added cruise control to the setup today.

J57ltr · 05.10.2011, 04:48 PM

I am going to have to come test it out!

snellemin · 05.10.2011, 05:21 PM

As of 12pm, I've reconfigured the bike to 18S. The hub was getting to 125F with the 20S and a few mph less isn't going to kill me.

J57ltr · 05.10.2011, 05:50 PM

wuss.

snellemin · 05.10.2011, 05:59 PM

It's Mr Wuss to you.

J57ltr · 05.10.2011, 10:30 PM

*Mrs.

snellemin · 05.13.2011, 01:15 AM

Mr Wuss soldered up another wiring harness and can run 22S now. Acceleration at that voltage is just nuts on a bike. I got goosebumps testing it out. The goosbumps can also come from me not wearing a shirt speeding in the middle of the nite on a bike.

JERRY2KONE · **Considering. -** 05.13.2011, 04:18 AM

Quote:

Originally Posted by snellemin

Mr Wuss soldered up another wiring harness and can run 22S now. Acceleration at that voltage is just nuts on a bike. I got goosebumps testing it out. The goosbumps can also come from me not wearing a shirt speeding in the middle of the nite on a bike.

Well considering that you were already seeing higer temps at 20S what are you getting for temps with 22S? Its been good to see and share in all of your testing with this project, but considering what these bikes can really be used for it sounds like 18S is sort of the sweet spot for an around town E-Bike. I mean really who needs more than 30mph on a mountain bike anyway just to get around town.

So IIRC with the original stock chinese e-bike kit for under $300 18S seems to be the cheapest setup for good power, acceleration, and keeping things safe. But when you factor in the cost and fabrication of a good battery pack for this it can get a bit expensive. Seriously while wearing one of those styraphome bicycle helmets I would not want to go much over 30mph and risk dangerous head injuries. Wearing a motorcycle helmet while riding on a mountain type bicycle would look kind of foolish. Otherwise it would seem best to go with an E-scooter if you want more power. This has been a very educational experiment.

Personally I am still on the fence between the E-bike kit, and an E-scooter. Looking at the financial aspect both would end up costing right about $2000 for everything involved, but the scooter comes pretty much RTR. Tough decision. I am hoping to start work in the next 4 to 6 weeks and traveling under 20 miles round trip into Prague and back home, so one of these would be a great alternative in fair weather from having to drive our van or taking public transportation. Seems to me that the easiest route would be the E-scooter, because it not only comes RTR, but it has lights, horn, and good lockable storage capacity. Plus stealing an E-bike would be much easier. The pros & cons lead me to think that a scooter would be the better path. Once working and having a little bit more money to play with I may build an E-bike with my boys purely for the experience and sharing father-son time with them. Your threads has given me ideas and great intel on what direction to go. Thank you.

snellemin · 05.13.2011, 08:13 AM

The 22s is just to experiment with. Nothing permanent. I'll check the temps today on my way to work. It's not hot out this morning, so I should be ok. After work I'm dropping back to 16S, which is the sweet spot for the setup. Above that voltage, it looks like and Escooter is the better choice, when you consider personal safety.

J57ltr · 05.13.2011, 09:01 AM

I was going to say, need I remind you of the longboard incident?

Jeff

snellemin · 05.13.2011, 09:40 AM

Yea, I remember the longboard. I still use though, but not as often as I use too.

Ok, so I averaged 38mph with the 22s. Motor hub was 99F, controller was less than that. I peaked at 49.48A, which calculates to over 4000W. I was pulling 20A continuous at max throttle and used 2629mah.
The new brakepads I got from REI, slow downs the bike alot better. To get rid of the brake squeel from the front, I toe'd in the brakes pads. I still have to play with it some more to quiet it down all the way.
To prevent me from locking up the the front under any cirumstances, I used some silicone oil on the pads. It's like having antilock brakes in the front now. I can squeeze as hard as I want and not lock up. I still have no need for diskbrakes in the front.

J57ltr · 05.13.2011, 12:43 PM

38 mph? You better watch out before you end up going back in time.

Jeff

snellemin · 05.29.2011, 09:24 PM

Made a ghetto fiberglass tub and covered it with me favorite green/black fleece. Bike handles better now.