Search found 257 matches

by Drum
Feb 07 2015 8:54pm
Forum: EBike Non-hub Motor Drives
Topic: BIG BLOCK alternative Motor
Replies: 452
Views: 98253

Re: BIG BLOCK GNG alternative Motor

Hi Sascha, When you say "Bending swingarm" do you mean that the tubing of the swingarm bends because of the chain tension, or do you mean that the swing arm is "pulled upwards" by the chain tension? In my case, the motor is bolted to the swingarm itself and moves with it, so chai...
by Drum
Feb 02 2015 11:03am
Forum: EBike Non-hub Motor Drives
Topic: BIG BLOCK alternative Motor
Replies: 452
Views: 98253

Re: BIG BLOCK GNG alternative Motor

Hi Sraff, BHT packed the motor reasonably well... not great, but not bad. It arrived with the ends of 2 or 3 cooling fins slightly bent, which were easy to straighten out (I used a small Crescent spanner). I couldn't see any matching damage on the box, and wondered if the fins were bent before shipp...
by Drum
Feb 01 2015 2:20pm
Forum: EBike Non-hub Motor Drives
Topic: BIG BLOCK alternative Motor
Replies: 452
Views: 98253

Re: BIG BLOCK GNG alternative Motor

For those of you who haven't seen it, This web page http://detail.1688.com/offer/1012215126.html includes test report tables and motor curve graphs for the motor that is the topic of this thread. The web page is in Chinese but the graphs and tables have enough English words and numbers to be useful....
by Drum
Feb 01 2015 1:29pm
Forum: EBike Non-hub Motor Drives
Topic: BIG BLOCK alternative Motor
Replies: 452
Views: 98253

Re: BIG BLOCK GNG alternative Motor

Hi Sraff, Before buying my motor, I e-mailed YK Success directly trying to buy direct from them. I did not get a reply. If you were willing to take the risk, you could try using a Taobao agent to purchase direct from YK Success and ship it to you.. it would undoubtedly be the cheapest way. I conside...
by Drum
Feb 01 2015 1:17pm
Forum: EBike General Discussion
Topic: My workshop (by popular demand)
Replies: 13
Views: 2614

Re: My workshop (by popular demand)

Hi Matt, Having built an ocean-capable cruising yacht and lived / traveled on it for several years, I know about making every cubic millimetre count. I also for many years earned my living as a one-man-band mechanical engineer working out of a modest sized workshop. I can therefore understand and ap...
by Drum
Jan 13 2015 1:34pm
Forum: EBike Non-hub Motor Drives
Topic: BIG BLOCK alternative Motor
Replies: 452
Views: 98253

Re: BIG BLOCK GNG alternative Motor

John, Here's a simple way to measure slopes (in degrees): Buy a spirit level with a rotatable element, put the level on the slope and rotate the dial until the bubble indicates level, then read the angle off the side. Cheap Chinese levels with this feature are cheap, and good enough for the purpose,...
by Drum
Jan 12 2015 12:17pm
Forum: EBike Non-hub Motor Drives
Topic: BIG BLOCK alternative Motor
Replies: 452
Views: 98253

Re: BIG BLOCK GNG alternative Motor

With the high centre of gravity of the bike / rider and the short wheelbase of an electric bibycle, I would be extremely surprised if you could ride up a 100% (45 degree) slope at a steady speed regardless of torque or gearing. I think you would wheelstand if you had traction, wheelspin if you didn'...
by Drum
Jan 11 2015 1:30am
Forum: EBike Non-hub Motor Drives
Topic: BIG BLOCK alternative Motor
Replies: 452
Views: 98253

Re: BIG BLOCK GNG alternative Motor

Hi John, I agree that if you have room and do not mind the extra weight, buying a motor that is rated for the power you want makes sense, but the extra 60mm diameter and 5.6kg of weight are unacceptable for an off-road bike, especially when you are trying to fit it within an existing frame and suspe...
by Drum
Dec 13 2014 1:46pm
Forum: EBike Non-hub Motor Drives
Topic: Gettin' "Jiggy" with it! (Frame Jig)
Replies: 13
Views: 1581

Re: Gettin' "Jiggy" with it! :)

I like it Matt, Those aluminium extrusions allow rapid construction of rigid structures without the warping that can occur with welded structures, and allow great adjustability. As you say, there is good access for virtually all the welds needed on a frame, and no problem adjusting angles and positi...
by Drum
Dec 04 2014 1:48am
Forum: EBike Non-hub Motor Drives
Topic: Downhill project motorcycle transmission
Replies: 304
Views: 39496

Re: Downhill project motorcycle transmission

Hi Dunkenb, Looked at images for the Mongoose ECD.. very interesting! lots of room under the frame triangle for the motor / gearbox. I would think you will be putting MUCH more torque through the clutch / gearbox than the original motor.. hope it stands up ok. Looking forward to the build... I think...
by Drum
Dec 02 2014 2:31am
Forum: EBike Non-hub Motor Drives
Topic: Kona Stinky, no pedals, big block on swingarm.
Replies: 81
Views: 16974

Re: Kona Stinky, no pedals, big block on swingarm.

Hi Stielz, Thanks for the comments and ideas. I am doing quite a bit of research on the fuse / circuit breaker situation. I think I am heading towards fuses in the battery pack and circuit breaker as the main switch as well. I have discovered "Noark" brand high voltage DC circuit breakers ...
by Drum
Dec 02 2014 2:16am
Forum: EBike Non-hub Motor Drives
Topic: What would the best full suspension bike be (features)?
Replies: 45
Views: 7572

Re: What would the best full suspension bike be (features)?

Hi Matt, I imagine you will get many different answers, as each person has different riding terrain in their neighbourhood, different skill levels, experience and expectations. So let's kick off my reply with a bit of background: I have 4 grandchildren (so far) and I have discovered that I bruise ea...
by Drum
Nov 26 2014 1:41pm
Forum: EBike Non-hub Motor Drives
Topic: Revolt Rv-120 -- Sine wave-- Specialized big hit
Replies: 87
Views: 20165

Re: Revolt Rv-120 -- Sine wave-- Specialized big hit

HiDirkdiggler, Regarding your suggested motor position: As well as raising the centre of gravity of the motor and moving it rearwards (both of which are bad effects on a high power bike), it would almost certainly increase the "effective unsprung weight" by positioning the motor where it m...
by Drum
Nov 20 2014 1:17am
Forum: EBike Non-hub Motor Drives
Topic: Downhill project motorcycle transmission
Replies: 304
Views: 39496

Re: Downhill project motorcycle transmission

When I posted this morning I was a bit pushed for time, and I hadn't looked at the photos of the original shape of the hub. Now I have done that, I agree with Matt.. the hub was almost certainly not strong enough to start with, and (unless the spokes were loose) side force was probably more of an is...
by Drum
Nov 19 2014 2:01pm
Forum: EBike Non-hub Motor Drives
Topic: Downhill project motorcycle transmission
Replies: 304
Views: 39496

Re: Downhill project motorcycle transmission

Hi Eco, these high power beasts are definitely overloading standard bicycle components, even full-on downhill ones. I think the torque that can be transmitted to the rear hub under acceleration is MUCH higher than the braking torque because of weight transfer: When you are braking, weight is effecti...
by Drum
Nov 17 2014 2:31am
Forum: EBike Non-hub Motor Drives
Topic: Kona Stinky, no pedals, big block on swingarm.
Replies: 81
Views: 16974

Re: Kona Stinky, no pedals, big block on swingarm.

Another question on the battery packs: 1) I hope never to have a battery fire, but if I do, I do not want an explosion caused by pressure building up inside a very strong battery box! Therefore I am guessing that I need to provide some form of venting,that would suppress flames as much as possible b...
by Drum
Nov 17 2014 2:18am
Forum: EBike Non-hub Motor Drives
Topic: Kona Stinky, no pedals, big block on swingarm.
Replies: 81
Views: 16974

Re: Kona Stinky, no pedals, big block on swingarm.

Ok, Being a mechanical engineer, things so far have been within my comfort zone, but I am now getting into new fields.. the battery packs. I have enough electrical knowledge to fully understand the basics: Amps, Amp.hours, Volts, resistance, series, parallel etc, but I am new to LiPo and EV batterie...
by Drum
Nov 15 2014 2:43am
Forum: EBike Non-hub Motor Drives
Topic: Split-crank Electric Tricycle
Replies: 10
Views: 3914

Re: Split-crank Electric Tricycle

Quite right Warren.. Obviously I hadn't been awake very long when I posted this morning!! :oops: Yes, just run the chain over one and under the other. Will still need freewheels to allow pedaling without having to turn the motors, but allow the motors to drive the chain when powered up, if that isn'...
by Drum
Nov 14 2014 1:23pm
Forum: EBike Non-hub Motor Drives
Topic: Split-crank Electric Tricycle
Replies: 10
Views: 3914

Re: Split-crank Electric Tricycle

Hi Robo. Using two small geared hub motors with freewheels to drive the chains in the Stokemonkey arrangement sounds like a good option. If you wanted the installation to be symmetrical you would need one left-hand and one right-hand freewheel and the motors would rotate in "opposite directions...
by Drum
Nov 12 2014 2:54am
Forum: EBike Non-hub Motor Drives
Topic: 2 speed mid-drive build
Replies: 37
Views: 8567

Re: 2 speed mid-drive build

Hi Ksi, Looking really good. not much force needed to shift, so more options on gearchange mechanisms. I hope your wife feels good that she has contributed to the project.. It's good when whole families share a project! Agreed.. very important that neutral always happens between first and second.. l...
by Drum
Nov 10 2014 1:50pm
Forum: EBike Non-hub Motor Drives
Topic: CYCLONE MOTOR OVERHEATING
Replies: 24
Views: 4832

Re: CYCLONE MOTOR OVERHEATING

Hi Hennez, I know almost nothing about the Cyclone motors or kits, but if I am right they use brushless motors. If so, and if they have Hall Effect sensors, it is possible that you have an incorrect wiring combination on your hall sensors. That can allow the motor to run but with incorrect timing in...
by Drum
Nov 09 2014 11:48pm
Forum: EBike Non-hub Motor Drives
Topic: Kona Stinky, no pedals, big block on swingarm.
Replies: 81
Views: 16974

Re: Kona Stinky, no pedals, big block on swingarm.

Hi Askor,
if you had the time, and wanted to come up & see the bike one evening, you'd be welcome. pm me..
Where is home?
Dave
by Drum
Nov 08 2014 1:58pm
Forum: EBike Non-hub Motor Drives
Topic: Kona Stinky, no pedals, big block on swingarm.
Replies: 81
Views: 16974

Re: Kona Stinky, no pedals, big block on swingarm.

Hi Rodgah, I guessed the problem with the pictures was to do with their pixel count, as it started when I bought a new cellphone with a higher resolution camera. I "shrunk" the photos by e-mailing them to myself and ticking the "make smaller for e-mail" option, but obviously that...
by Drum
Nov 07 2014 11:23pm
Forum: EBike Non-hub Motor Drives
Topic: Kona Stinky, no pedals, big block on swingarm.
Replies: 81
Views: 16974

Re: Kona Stinky, no pedals, big block on swingarm.

Can anyone tell me why my photos are not displaying in my posts anymore? The only thing I can see different is that the photos less than 60 kiB display and the photos larger than 60kiB do not.. is that it? If so, I will have to figure out how to shrink them even more.
by Drum
Nov 07 2014 11:20pm
Forum: EBike Non-hub Motor Drives
Topic: Kona Stinky, no pedals, big block on swingarm.
Replies: 81
Views: 16974

Re: Kona Stinky, no pedals, big block on swingarm.

Real progress the last 2 evenings and today... The bike has brakes (borrowed off a freeride bike my son has outgrown), and I made a bracket to mount the rear brake to my swingarm back end. A bit more work to do in that department but I now have the basic shape of the bracket sorted and the brake is ...