Monday, November 25, 2013

Couldn't Wait

I'm still waiting on some parts to complete my electrick trike conversion but couldn't stand it any longer and hooked it up yesterday in the friction drive mode. I had tried this a little with a brushless drive that was too small and it worked at low speed but was slipping a lot. I added more bungees and then when I tried to roll on throttle it sounded like the drive was out of sync with the motor. I tried it at several different speeds with the same effect... finally added a bunch of throttle and it promptly smoked the drive. Luckily didnt smoke the battery... it had melted one of the power solder connections to the drive which saved the battery. 

After reading some posts about others using a friction drive arrangement I decided to try it again. I didn't smoke anything this time but I did manage to grind a little off the OD of the tire. I could have added more bungees but thought I was already pushing the limit on how much of a side load I wanted to have that far out from the bearings.

I got the new hub and rim and I've made an adapter to mount a chain ring on the brake rotor mount. Still waiting for spokes for the wheel so tried this one more would do about 17 miles an hour on level ground. It is a 245 KV motor and I was running it on 22 volts.I don't believe I'll have any problem getting 25+  miles an hour out of it on 44 volts.

Monday, November 11, 2013

In Flight Adjustment Take 2

I was hoping to use a belt drive from the motor reduction to the rear wheel.... but it is pretty much a custom piece and pretty pricey and the source for this piece has been a bit difficult to communicate with.

So for a number of reasons... primarily price and easy availability I've decided on a little different route. Instead of a one way bearing and belt drive... I'll be using a BMX freewheel in reverse mode... driving instead of driven... and a crank chain wheel on the rear wheel. It is is going to require a new rear wheel with a mountain bike type hub with provision for a disc brake rotor mount.

I created a spread sheet to analyze the gear ratios needed to end up with a target speed of about 30 mph. My home built trike has a 24 inch rear wheel so it requires a little more reduction in the drive train than would a 20 inch rear wheel. Still debating somewhat..... whether to use an existing motor that I have.... or bite the bullet and go for one of the Astro motors.       

Some parts will be the same either way but going to try to keep it as simple as possible. A 44 tooth chain wheel on the rear wheel.... bored and drilled to fit the brake rotor mounting holes. A 13 tooth BMX freewheel driving that. It will require a  a custom piece to mount on to a 16 mm jack shaft. On the other end of that shaft will be a 5mm HTD belt drive pulley and a smaller pulley on the motor to complete the drive train.                                                                                                  

Wednesday, November 6, 2013

An Inflight Adjustment

Welll after riding Outriders Cadillac I've decided to make a few course corrections. I'm planning to follow their lead on a few things... a parallel belt drive on the opposite side from the normal bike chain drive... a one way bearing to allow the bike to freewheel when not on the power.  On the control side.... no power to the motor until the bike is moving and limiting max power to extend run time and reduce drive train loads.

motor, drive pulleys, plain steel jack shaft running in bronze bearings