72V Motorcycle Wheels Mac 6T Motor Street Ride

[torker]

Ah the genius of ES, So true.. And good you take the advice. So many ask and then don't. The insight posted by Cellman is spot on ... A slower wind in DD will "rock" on 72 volts @ 22.5 in. diam. My builds are old,low tech,on a budget . My 2810 in a 20 in. wheel with a soldered shunt @ 50 amps and 60 volts is a blast to 25 mph. Definitely put me right on my ass the first time I goosed it good 8) Ready to see some updates. Even at 72 volts if you keep the amps down it should live. Good luck.. Oops I forget it is a gear motor.. 48 volt would still be over 50 volts hot and good speed on a 6t.. Time to go to bed

 

[The Stig]

Just thought id post a couple of build pix...

Ug non-upgraded phase wires... and cell-man had told me i'd need a 12t MAC for 72V. Hope this works! And I hope you'll give it as much ground clearance as possible for jumping up curbs and over snow-banks(canadaaaaa) etc.

Give the MAC a fight chance and fill 1/4 to 1/3 of the way with Mobile 1 Synthetic ATF!
http://www.endless-sphere.com/forums/viewtopic.php?f=2&t=37972&p=729361#p729361

 

[mainsource]

lace that Motorcycle wheel on a DD hub

Not sure what a DD hub is... Could you pls elaborate?

 

[torker]

DD is direct drive. The three planet gears in a geared motor run about 5 times faster rpm than a direct drive, maybe it is 12 times faster Someone could explain this better than me but a direct drive is a lot tougher.
Oh I just reread thread. You may try to epoxy some screen over the vent holes to keep the nasties out..

 

[teklektik]

lace that Motorcycle wheel on a DD hub

Not sure what a DD hub is... Could you pls elaborate?

The ebikes.ca Intro Guide.

Basically - DD hubs have no internal gearing and as a result have poorer torque off the line (for the same power as a geared motor), have much better heat dissipation (magnets on interior of hub instead of on separate internal rotor), can generally be more easily be overvolted because the motor rpm is the true wheel rpm instead of 5x higher as with geared hubs, can be pushed to much higher speeds, are bigger and heavier than gear motors, and can do regen braking (no internal freewheel clutch). So - some pluses and minuses depending on what you want from your motor....

Your strategy to reduce the wheel size is a typical DD ploy to get more torque and rpm. This sort of bit you because you applied it to a gear motor. Re-lacing a DD motor will suddenly make that build decision an advantage instead of a problem.

 

[mainsource]

Thanks for all the recent updates... I purchased spokes and am about to do a re-lacing job... I will keep this thread updated regarding my progress... As for the MAC... I would take the popular advice to run it within its comfort zone. For this, I would go with an all bicycle project (wheels included) and at some later date.

 

[torker]

Ooh this mean you have a direct drive motor for it?

 

[The Stig]

An oil cooled 9C won pikes peak! In the "hub motors class" at least. It had upgrade phase wires of course.

 

[mainsource]

Before I dismantle anything, what do you guys think about this Turnigy C80-100 that Thud of ES rewound for me? The KV is now 55, and halls were installed. Since I already have the motor and never used it, I am considering this option as a direct chain or belt drive to the rear wheel (before purchasing another hub motor). I do have a hubzilla and a 5403, but they are planned for other very specific projects. Here is the video:

http://www.youtube.com/watch?v=DpM2McmM1ms

Can I expect better overall performance numbers from this setup as compared to the MAC? At least enough to justify motorcycle tires?

 

[The Stig]

Do both, Chain drive + MAC motor

 

[mainsource]

Great idea Stig!! I might just do that!!... Woah am loving this now!!

 

[mainsource]

The bike is finally finished and running approx 60V. Am not yet sure about the speed, but it feels fast enough (will post details later). Tire diameter is 22", and am running a 60T chainring. With this setup, I easily run out of cadence (so am guessing past 100 revs). The bike still climbs 12% grades with some minor pedal assist.

 

[Ch00paKabrA]

looking good. I am running a MAC 6T as well at 14S so roughly 58v fresh off the charger and my top speed is mid 30s since I am only running 25 to 30 amps.

Paul at EM3EV told me in an email that the 6Ts are hard to get their top speed out of because they need a lot of amps and doing so generates a lot of heat.

The plan for me was (maybe still is) to add a second MAC 6T to the front. With 2 you can get to 40 with a 26 inch tire.

When you finally do a full speed test, please post your results: top speed, battery configuration, and amps.

Great bike! and good luck with it.

 

[The Stig]

Wow looks good! Lots of building/fabrication. Is that the battery box right over the front tire there?

 

[waynebergman]

It looka like a hose clamp on the fork tubes to lock out forks but not sure. I also noticed this earlier and thought if this fork has working travel there is a danger of going over the bars if the tire hits the fabrication work.If this forks does have a travel of more than a few inches I think once the tire hits the fabrication under compression it could move rider weight forward making the braking effects even worse and could be dangerous.

 

[KalSteve]

Yeah Wanye, it does look a bit of a faceplant waiting to happen. If it's timed right, that machete mounted above the rear tyre should bury itself into the back of the riders head as well.

Not sure if I would be game to pilot this one.

 

[The Stig]

You people are such a buzz kill...maybe hes waiting for a new fork that would raise the front end and have limited travel so it the tire wouldnt rub. Maybe relocate the battery a bit??

 

[cal3thousand]

Looks like the rear was locked into a hardtail now?

And I want more details on your rear rack there. Any close up pictures or details of the design and how well it works?

 

[Ch00paKabrA]

You all are way more observant than me. :lol:

It does beg the question that if you are going to lock out both front and rear suspension, why not just use a hard tail and stuff everything in the triangle? Perhaps the initial intention was not the make the bike a rigid but it evolved into it by necessity.

 

[mainsource]

Perhaps the initial intention was not the make the bike a rigid but it evolved into it by necessity.

This is precisely what happened, The bike evolved into its current status based on components that were either available or eventually procured. Eg I had to find a frame / fork combo to fit the wheels/ tires while still running disc brakes - and this is where/ when I stopped looking. l also hoped that the battery box could have been short enough to clear the front tire but, in a quick left turn, gave priority to maximum battery carrying capacity. If I eventually afford a dh fork id limit it's travel short of the battery box.

 

[mainsource]

I've decided to post the battery box cover detail. Its the latest addition to the bike.

 

[mainsource]

Hope this pic helps

 

[Ch00paKabrA]

The more I look at the pictures of your bike, I can't help but wonder. You obviously have some fabricating skills or know someone that does. It seems that you are wasting a lot of space in the front triangle and just behind it. If you flipped the pivot brackets up-side-down, it would free up just about the entire triangle for batteries. You would need to cut the existing mount off of the down tube and weld it to the seat tube. You could then make a battery box for the triangle. and mount the controller under the down tube (or build an enclosure for it attached to the down tube and run the large mass of wires under the bottom bracket into an enclosure constructed behind the seat tube

This would do 2 things. It would negate the need for a rear rack and it would allow your front suspension to work. Basically it would just be a hardtail with a front suspension.

Here is my absolutely pathetic photoshop rendition of what I am taking about (grey is aluminum enclosure, red is controller):



Not sure if this is the type of comment that you were looking for and I hope you don't take it as negative criticism.

Good luck with you bike no matter what and I am still interested in your top speed when you determine it.

 

[made_in_the_alps_legacy]

The bike is finally finished and running approx 60V. Am not yet sure about the speed, but it feels fast enough (will post details later). Tire diameter is 22", and am running a 60T chainring. With this setup, I easily run out of cadence (so am guessing past 100 revs). The bike still climbs 12% grades with some minor pedal assist.

Oh man... I like your huge chain ring, that's it.
[...]
I would recommand you to seriously consider "Ch00paKabrA" proposal

 

[mainsource]

I definitely appreciate and embrace the comments regarding battery box re-location. I will take a closer look at executing the suggestions, because at 35 miles an hour, a front suspension becomes fairly important. For the benefit of this forum, running low pressures in motorcycle tires that are mounted to relatively lightweight ebikes do little to mitigate the harsh ride experience. this because of the tough rubber used in the tire's construction. There is some give, just not enough.

I will post a speed, but first i need to replace the controller. I was warned on this forum about the mismatch between the infineon DD controller and the mac, especially at higher voltages (60V plus in my case). Well i think my controller died and needs to be replaced. All suggestions are welcome. I would definitely want to keep running my CA.