What about an electric Bucket?

[TZ350]

Pumping the tyres up higher than normal reduces rolling resistance..............

[Buckets4Me]

Try an MB100 engine & stop pissin around

getting worried that your 10% chance of turning up with a running bike quote is going to be used again

[koba]

one serious outa three answers aint bad

thanks for the tip bout the master, will try with the current one anyway, as the sponge in the brake lines may cause it to retain feel. The problem isn't power or weight, just battery capacity, so to get more range I gotta reduce the cruising current. May replace the seals in the brakes as well to see if that helps. Good thing is I get an instant readout of how much effect each change has, so I'll let you know if I find anything new that helps...

If the brakes don't show any obvious signs of dragging I wouldn't waste your time.
Always address bottlenecks first, if the bottleneck is the battery capacity work on that!

[bogan]

If the brakes don't show any obvious signs of dragging I wouldn't waste your time.
Always address bottlenecks first, if the bottleneck is the battery capacity work on that!

well it's a two fold issue, theres not enough capacity for long range, and the power used to go 50kmhr is too high (so the capacity doesn't take me as far), it's around 3kw, and it should be about half that. But yeh, will find some stands and see where the rolling friction bottleneck is.

[koba]

well it's a two fold issue, theres not enough capacity for long range, and the power used to go 50kmhr is too high (so the capacity doesn't take me as far), it's around 3kw, and it should be about half that. But yeh, will find some stands and see where the rolling friction bottleneck is.

I guess you have a fine balance too with more battery meaning more power capacity but also more weight to haul around...

[koba]

I don't know if it translates directly but an average bucket would put out around 14hp PEAK which is a bit more than 10 kilowatts...

[bogan]

I guess you have a fine balance too with more battery meaning more power capacity but also more weight to haul around...

yeh, and it's a bit of a bastard to fit big blocky SLA's into a modern sports motocycle frame, could maybe get one more in there, which would be an extra 33% capacity.

[mattbishop]

Hey Bogan,

For comparison, at 50 km/hr, my bike draws 35 A. I've about 50 v across the battery pack so around 1.8 kW. That's not too different from your observations. Could be your motor efficiency is not great at that speed, 50 km/hr road speed gives me about 1200 RPM at the motor so I'd expect less than 95% efficiency, maybe around 80%.

Do ya see they'll be racing electric bikes in Aussie next year?

[bogan]

Hey Bogan,

For comparison, at 50 km/hr, my bike draws 35 A. I've about 50 v across the battery pack so around 1.8 kW. That's not too different from your observations. Could be your motor efficiency is not great at that speed, 50 km/hr road speed gives me about 1200 RPM at the motor so I'd expect less than 95% efficiency, maybe around 80%.

Do ya see they'll be racing electric bikes in Aussie next year?

an extra 1.2kw is a lot of wastage though (iirc its geared for 80kmhr at max motor rpm, so around 2000rpm at 50kmhr), I turned up a fitting to block of one brake hose, so should get some testing in with one caliper this week, hoping to get the charger tuned properly so can start on some range tests also.

good to hear electric racing is expanding, by the time it gets here I may just be ready for it

[F5 Dave]

So you really think that brake bind is slowing you down? Please! I mean unless there is a problem. Does one disc get considerably hotter when riding & not using the brake?

To test for drag, why not just ease the pistons back a touch so there is no friction. You'd need to count the number of times you need to pump the lever to get full power, but if you experimented on the driveway you should get it so there is no drag & 1 pump to get back to normal.

Why do you need to turn a fitting? Sounds like non std brake parts & in my experience bedding in can cause a failure. At least the slightly dangerous scenario I suggested above is a known temp experiment.

[bogan]

So you really think that brake bind is slowing you down? Please! I mean unless there is a problem. Does one disc get considerably hotter when riding & not using the brake?

To test for drag, why not just ease the pistons back a touch so there is no friction. You'd need to count the number of times you need to pump the lever to get full power, but if you experimented on the driveway you should get it so there is no drag & 1 pump to get back to normal.

Why do you need to turn a fitting? Sounds like non std brake parts & in my experience bedding in can cause a failure. At least the slightly dangerous scenario I suggested above is a known temp experiment.

just did some 'spin' testing, lifted front wheel off the ground and spun it by hand then counted turns.

Both calipers 3/4 of a turn
LH caliper 7/8 of a turn
no calipers fucking heaps
RH caliper 5.5 turns

so guess which one is no longer attached. The fitting was a little ali cylinder to block off flow to the second caliper (same size as the banjo), tried to find a replacement bolt but was a not too common size.

Did similar test with the rear, was around 2-2.5 turns, and thats including 4x as many spins on the motor.

So not inconceivable that I may cut the cruising current by a third, gutted theres wires hanging out and I can't test it now...

Will have to take that caliper apart to see what was wrong with it, probly knackered seals I'm guessing.

[Jantar]

just did some 'spin' testing, lifted front wheel off the ground and spun it by hand then counted turns.

Both calipers 3/4 of a turn
LH caliper 7/8 of a turn
no calipers fucking heaps
RH caliper 5.5 turns

so guess which one is no longer attached. The fitting was a little ali cylinder to block off flow to the second caliper (same size as the banjo), tried to find a replacement bolt but was a not too common size.

Did similar test with the rear, was around 2-2.5 turns, and thats including 4x as many spins on the motor.

So not inconceivable that I may cut the cruising current by a third, gutted theres wires hanging out and I can't test it now...

Will have to take that caliper apart to see what was wrong with it, probly knackered seals I'm guessing.

One of the reasons why I'm still a fan of double leading shoe drum brakes for small bikes.

There is no drag as the brake shoes are pulled off the drum by a spring.

[TZ350]

Will have to take that caliper apart to see what was wrong with it, probly knackered seals I'm guessing.

In older calipers some sort of crystalline crap can build up in the cylinder and behind the seal jaming the piston, a strip and clean often gets it working again.

When a caliper is working properly, after the brakes are applied then let go the seals should pull the pistons back a thou or so and free the pads so there is virtually no drag.

F5Daves post on brakes is timely as we are cleaning up the brakes on my new FZR bucket. Check out his post as there is plenty of good info there…..we did.

After dismantling, the gunk is scraped out of the piston seal groves and from the back and sides of the piston seals themselves and the pistons cleaned up. Hot water or Meths washes out brake fluid and cleans up rubber parts and Kero or the like can be used to clean road gunk of the metal parts.

An original post about cleaning brakes on the Team ESE thread.

I am watching your progress on the electric bucket with interest.........

[bogan]

just got back from some testing, now has just a smidge more top speed, and less cruising current, around 55kmhr and 55amps, +-5 on each for insrumentation error probably. Which is a neat number as it's one amp hour per kilometer so my 15km commute should be doable on a single charge. Both discs were still fairly warm after the ride, but unsure how much of that was from stopping, think I'll rebuild the lot anyway.

[Yow Ling]

seeing as this bike is currently going at scooter speeds why not ditch the big disks and calipers dseigned to pull up the bike from 200kph, and replace them with smaller lighter disks and a single little scooter caliper