MAC 7T ?!?!

[TonyReynolds]

erm, isn't it at 700c wheel with a 2in. tire on it?

That is what many bicycle shops have told me.
Bicycle wheel sizes are based off the total diameter of the expected tire plus the rim itself.

So for example, a 20" wheel in bike terms is a 16" wheel in motorcycle terms, because there is usually a gigantic tire on the thing.

Technically the rim is 622mm by whatever the INSIDE rim width is (typically 18-20mm). "29er" is a marketing term, not necessarily reality, but that said, my 622 rim, plus a 2.0" (50mm Schwalbe) tire is very close to 29" in diameter. Here's an article about it:

http://en.wikipedia.org/wiki/29er_(bicycle)



(29er on left, 26" on right)

[neptronix]

OK, seems like what we consider 700c in the states. Bicycle wheel sizes should be like motorcycle sizes.. rated by the outside rim diameter only. silly

[Polerkongen]

Ive done a whole lot of reading and asking questions to decide the right kit, I knew virtually nothing about ebikes when I joined up here, finally decided on cellman mac kit with the 52v triangle battery, I'm opting for the 8T as it will still get 30mph+ with the 52v a123.

When a 29 inch I too would choose an 8T, in strong headwinds i can definelty feel the 7T is a high speed wind. So the 8T must be perfect for you.

I spend a lot of time trying to decide the battery setup, but having the oppertunity to hide the controller and all the wires in the triangle made me go lipo, thats the main reason. It ended up costing the same and with 16Ah, I only have 2Ah more than Pauls a123 when 15% being left in the lipo bricks.

[Wizzbit]

Ive done a whole lot of reading and asking questions to decide the right kit, I knew virtually nothing about ebikes when I joined up here, finally decided on cellman mac kit with the 52v triangle battery, I'm opting for the 8T as it will still get 30mph+ with the 52v a123.

When a 29 inch I too would choose an 8T, in strong headwinds i can definelty feel the 7T is a high speed wind. So the 8T must be perfect for you.

I spend a lot of time trying to decide the battery setup, but having the oppertunity to hide the controller and all the wires in the triangle made me go lipo, thats the main reason. It ended up costing the same and with 16Ah, I only have 2Ah more than Pauls a123 when 15% being left in the lipo bricks.

I got a 26" wheel, I nearly went lipo but decided on a123 because its simpler and they last longer, I guess IL camoflage my wires along the brake cable/gear cable.

[AmpeD]

Hi guys im in a similar dilemma with choosing between a 7t and 8t on a 26" but at 72v with 20amphrs what spec motor would be more suitable?

[Wizzbit]

Hi guys im in a similar dilemma with choosing between a 7t and 8t on a 26" but at 72v with 20amphrs what spec motor would be more suitable?

Well you've got plenty of power with that battery, it depends how fast you wanna go and what hills you wanna climb, but cell has told me expect 50kph on 8t with 52v a123, so you can expect serious speeds with a 72v, I would go 8t with those v's.
As for myself I'm just about to place my order with cell and deciding between 7t and 8t, but leaning towards 8t on neptronix recommendation, hmm little more torquey or little more speedy??

[olemetry]

one option that cell-man offers is this:

DCDC (component only), 3A OP, adjustable DC out, max 48V pack- 10USD

uhh, what is this? i can't make heads or tails of it. anyone have a idea?

[docnjoj]

It is a DC/D/C converter to bring the 48 volt battery down to 12 volts for lights and accessories. It is good for up to 3amps out at 12V.
otherDoc

[neptronix]

Hi guys im in a similar dilemma with choosing between a 7t and 8t on a 26" but at 72v with 20amphrs what spec motor would be more suitable?

10T or 12T.

On an 8T, you'll hit 46mph and the motor will burn up or your gears will melt.
Check the ebikes.ca simulator - that's 3000-5000w.

You don't want to exceed 40mph on these motors. 35mph is already pushing it.

[olemetry]

What motor should we select in the simulator for MAC's 7T, 8T, 10T, etc.? ALso what type of battery characteristics should I use for 12s lipo?

[Wizzbit]

Amped thats gonna be a beast with a mac 10T, let us know how it goes

[Wizzbit]

What motor should we select in the simulator for MAC's 7T, 8T, 10T, etc.? ALso what type of battery characteristics should I use for 12s lipo?

Im not sure, I was using bmc speed I think thats the closest thing to a mac 8t, but it shows the speed too low, so maybe its more like a 10T?

[olemetry]

I understand that the 7T will be fast enough for me at 48V. Cell_man advises that the IRFB3077 (75V fets, up to 48V battery pack) would be better than the IRFB4110 (100V fets, up to 72V battery pack) if I am only going to run at 48V. However, is this only because it is cheaper? Or will the 3077 run smoother than the 4110 at 48V? I ask because I may want to use the 4110 for a nother motor down the road, or just try to pump 15s - 16s into the 7T on rare occasion to see what I get. But if the 3077 has an advantage at running at 48V, then I would like to get that one. Anyone with insight?