Upgrade time! 40mph max speed target. Help

[electr0n]

I've had a chance to ride my bike a few times at 66.6v 40 amps and it's a lot of fun but when riding into a strong headwind I still feel somewhat under powered. I think my target is going to move up a little to 88.8v and 60 to 65 amps. Is that asking too much from a 12 fet lyen controller? What is the benefit of the 18 fet controller? Is it necessary for that power level?

[nicobie]

I've had a chance to ride my bike a few times at 66.6v 40 amps and it's a lot of fun but when riding into a strong headwind I still feel somewhat under powered. I think my target is going to move up a little to 88.8v and 60 to 65 amps. Is that asking too much from a 12 fet lyen controller? What is the benefit of the 18 fet controller? Is it necessary for that power level?

That's what I run and so far, so good.

[electr0n]

That's good to know the 12 fet can handle that power. I think I'm going to go with an 18 fet to be safe and give me some room for additional power in case I decide to get an x5 or something more powerful later.

Now I have another question regarding the halls. My motor stutters a bit particularly on modest inclines and also when I engage the throttle sometimes when using close to full throttle. It doesn't seem consistent. I usually notice it I'd guess upwards of 40kph. It's hard to describe it just doesn't feel smooth like the timing in the motor is off.

My question is it possible to have a working hall and phase combination that seems to be working almost perfectly but shows slight stuttering, could this be due to a bad wiring combination? I've been able to ride it into work and back twice now, plus a couple leisure rides. The thing works but there is this slight hesitation at times. It doesn't feel totally smooth at all times. Are there hall / phase combos that will work 90% good but exhibit symptoms like this?

My first guess is a bad connection at the phase or hall wires. I soldered the halls directly to the controller, but maybe one of them came loose or had a cold solder joint. My second guess is I've damaged one of the wires around the axle.

Any guesses? I hate to keep pulling the motor off and messing around with the delicate hall and phase wires around the axle.

[electr0n]

Well I took the side cover off to inspect the wires around the axle more closely. I found what looked like a burn mark and I cut off the white fiberglass stuff covering the wires expecting to find a partially cut wire or something but instead I found nothing. All wires appear to be intact. What looked like a burn mark must have been a grease stain or something.

Before opening the motor I also checked my soldered hall connections and they all appear to be well connected. Nothing was loose. The phase wires are in the Anderson connectors, I didn't inspect them too closely, not expecting a problem there. I was really expecting to have a wire partially cut in the axle groove. So now I'm at a loss. Maybe one of my battery connections is loose or something?

Any ideas? Opening the motor wasn't a total loss, at least I was able to spray the inside with some anti corrosion stuff. I also know for sure I have no wire cut issues, or at least I didn't notice anything obvious.

[GCinDC]

I hate to keep pulling the motor off and messing around with the delicate hall and phase wires around the axle.

why? don't you think it's fun? just kidding. i think it's about time some design a hinged access panel...

I found what looked like a burn mark and I cut off the white fiberglass stuff covering the wires

Any ideas? Opening the motor wasn't a total loss, at least I was able to spray the inside with some anti corrosion stuff. I also know for sure I have no wire cut issues, or at least I didn't notice anything obvious.

oh, whoops, this was from march?? i just tracked down this thread from some of your other q's, and thought it'd be the best place to respond.

are you still having this issue??

if so, i was going to say that i've had similar problems, and was only able to fix them by replacing the hall wires.

do you have more q's about power levels? ie, 88x 60A?

i've been running the same 12 fet 45A ecrazyman controller for 1.5 years now. but MAX i've had it to is 5kw (@24s), and average PEAK is 4kw @20s.

and to answer you q elsewhere, i have a lot of hills nearby, nothing like mountains, but nonassisted cycling is not very fun.

more to the point, what is your terrain? commute distance?

[electr0n]

Yes I'm still having the same intermittent stuttering issue. It happens mostly when I'm accelerating hard or if I'm pulling a heavy load (trailer) the motor will start having this sensation of ticking or misfiring. It's hard to describe. If I ease off the throttle a bit and then try to increase power smoothly it minimizes the problem. I've just been ignoring it since I don't care to replace the halls or wiring just yet.

It's interesting that the hall wiring fixed your issue rather than the hall itself. Was there a nick in the wire or something? They are really thin wires so I guess they could be damaged inside without necessarily showing damage on the insulation.

I'm now leaning towards throwing my HS into a 20" wheel. I don't think I'll have any issues with overheating if I do that. I should be able to run 88.8v and 65 amps no problem with that setup. Top speed is enough for practical purposes street riding with traffic. Battery capacity is the limiting factor riding at high speed anyway. The acceleration should be awesome in the 20" wheel, 130lbs of thrust, almost double what I have now!

My area is fairly flat but there are big hills around that I'd like to be able to go up without fear of my motor going up in smoke. The 20" wheel should take care of that. Most of my riding is on roads, sidewalks and paved paths. Commute distance is nil for now, but it was about 9km each way up until recently. My transportation is my bike, so it's more than just a hobby for me.

I've got an 18fet 4110 controller on the way plus 1 kilowatt hour worth of batteries. Now I'm just debating between 24" and 20" wheel to migrate my HS3540 to. Leaning towards the 20". Probably going to run 24" front 20" rear. Will throw up some pictures when everything arrives.

[electr0n]

I finally got a cycle analyst! No more range anxiety. Being able to see the battery voltage, amp hours used and instantaneous power is very helpful for getting the most out of my battery pack. Prior to having the cycle analyst I would always cut my rides short for fear of taking the battery down too low.

Seeing the real time power consumption has been illuminating. Power consumption goes up dramatically even on slight uphill grades and accelerating. If not being careful with the throttle it's so easy to ride very inefficiently.

The current limiting feature is nice with some tweaking of the settings. However the speed limiting setting so far has been very jerky. It's like the power goes off when the limit is reached and then it goes back on again at high power draw, not efficient at all. I was hoping the speed would be held steady at a low power draw like cruise control, but I suppose that's not the same thing.

[sn0wchyld]

I finally got a cycle analyst! No more range anxiety. Being able to see the battery voltage, amp hours used and instantaneous power is very helpful for getting the most out of my battery pack. Prior to having the cycle analyst I would always cut my rides short for fear of taking the battery down too low.

Seeing the real time power consumption has been illuminating. Power consumption goes up dramatically even on slight uphill grades and accelerating. If not being careful with the throttle it's so easy to ride very inefficiently.

The current limiting feature is nice with some tweaking of the settings. However the speed limiting setting so far has been very jerky. It's like the power goes off when the limit is reached and then it goes back on again at high power draw, not efficient at all. I was hoping the speed would be held steady at a low power draw like cruise control, but I suppose that's not the same thing.

check the manual for the ca... its something to do with how fast it reacts to your speed. ramp down that time, and it will react slower, enabling it to hold your speed 'smoothly-er'.

[electr0n]

Yeah I saw that there are some settings to tweak which is nice. I'm still messing around with it. I'm running a 40 amp controller and I turned the amp limit down to 15 and set the throttle to 1.68v to limit the max power and top speed at full throttle. Those settings work very well to extend range and tame the power when pulling my kid in a trailer.

[electr0n]

I've exceeded my stated goal of 40mph max. I've now got a top speed of 50mph and I'm pretty much at the limits of this motor without modifying it for better heat dissipation.

I've got an 18 fet lyen controller on the bike now, 3 speed switch and half twist throttle. After switching controllers and replacing a partially melted anderson connector on one of the phase wires my stuttering problem is gone. I've had the bike up to 88.8v nominal at 35 to 37 amps. The performance at this power level is a lot of fun. The motor does get quite hot after a brief 10 to 15 minute ride so I'm trying to be careful. I want to pick up a thermometer and maybe drill out the side covers. I'm just not too excited about pulling the stator out for fear of damaging something.

The 3 speed switch is very handy. I can already limit the throttle via the cycle analyst but it's nice being able to do it with the flick of a switch. I'm not sure if I like the half twist throttle. I find it hard to hold a certain speed compared with the thumb throttle.

Here's how the bike looks now. Pretty standard stuff. I have the batteries in two separate handlebar bags. One bag sits on a pair of right angle brackets which are hose clamped to the fork. The other bag sits on top and is velcro strapped to the handle bars. I've got a strap from an old backpack holding the bottom bag on the brackets and an additional stretchy velcro strap for additional support. This setup works very well. The bike still handles quite good. Steering is not affected aside being a little stiffer to turn due to the weight. Nothing bounces around and the cheap front suspension is not affected much either.

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