Dahon Jetstream conversion

[patpatbut]

I have both a Cute100H and BPM bare motors on my hand, it doesn't turn much on when I push it and I can feel some drag.

That is strange...Sorry to ask are you sure you move the wheel at the right direction? Geared motor can do freewheel on one direction.

Pat

 

[cwah]

yeah, it doesn't freewheel at all on the other direction anyway

 

[eHomer]

I have both a Cute100H and BPM bare motors on my hand, it doesn't turn much on when I push it and I can feel some drag.

My impression of "freeness" from drag on my Cute Q100 is that it's ok now that I reversed that inner nut. Turning it the other way of course, the drag from the gears is very noticeable by comparison.

I know that running on for just 5 seconds or so seems a lot less than when you spin a conventional bike wheel in a good hub, where it can spin on for a minute or so, but I put that down to the newness of the greased ball race, and the absence of the tyre's weight around the rim.

The flywheel effect of a touring grade tyre and tube on a 26" rim must be much greater than an empty 20" rim.

 

[cwah]

This is how my BPM freewheel now:
[video=youtube;vkTcd72l7pI]http://www.youtube.com/watch?v=vkTcd72l7pI&feature=youtu.be[/video]

As good as my little direct drive conhismotor lol

 

[patpatbut]

This is how my BPM freewheel now:
[video=youtube;vkTcd72l7pI]http://www.youtube.com/watch?v=vkTcd72l7pI&feature=youtu.be[/video]

As good as my little direct drive conhismotor lol

My bafang CST and SWXH motors can freewheel much better than this. It does look like the motor is rubbing with the something...

 

[cwah]

it does not rub against anything. I double checked. My other bpm and Q100H behave the same way

 

[patpatbut]

Wait. Maybe I am wrong as I did test the wheel using the throttle so it is not bad as you think.

Dave said it will get better overtime when it is on the road.

Pat

 

[Deleted member 4366]

When you turn any bare hub-motor in your hand, it will feel stiff when new. Did you look behind the nut on the one on your bike?

 

[cwah]

do you mean this nut?

there is no nut on the cable side

 

[eHomer]

do you mean this nut?

there is no nut on the cable side

That does look very similar to the bearing seal on my Q100, and is on the opposite side to the cable entry.

Is that nut symmetrically beveled ?

Try loosening it slightly and spinning the wheel by hand then.

 

[cwah]

I finally had to go back to london so I can't check that now. I'll do that when I go back to paris.

I'm thinking to get a magura throttle:
http://item.mobileweb.ebay.co.uk/viewitem?sbk=1&nav=SEARCH&itemId=230776437368

Is this one the right one for 100% linear response? Wiring as simple as normal throttle?

Thanks

 

[Deleted member 4366]

That's a cable throttle for a motorbike. Try searching for a "Magura 5K throttle". They're around $50 plus shipping.

 

[cwah]

The nipples of my bpm laced by bmsbattery always get loose

I tighten them but they get loose again so quickly.

When I'm cycling it's like dancing samba!!

 

[cwah]

my bike is almost complete:

Thanks to d8veh I've now a rear disc brake which is super nice.

I've placed the batteries on the frame for balance. It's a big battery of 72v20ah ahah, almost 1500wh. I'm cycling them to see how they perform

 

[Cyclezee]

Not exactly stealthy cwah, but I guess that wasn't the object of the exercise.

Out of interest what does it weigh, how does it handle and perhaps most importantly, how does it stop?

 

[Kramer]

 

[cwah]

The bike all included should weight around 25kg (4kg motor +10kg battery+11kg bike + some bits)

Handling is quite good because mass is all located on the bike frame. It handles better than my brompton. Ride are quite pleasant. Previously the battery was on my backpack and it gave me some pain in the back, now it's on the frame and it's way better.

And brakes are not bad either, although when it reaches high speed it gets a bit dangerous. I don't have a speedometer with me (the one I bought is broken) but wheels tend to slip when I brake over 25mph. So 90% of the time I'm running around 25mph.

I've been thinking a long time to find out where to put the battery, my experience on the front and back of my previous bikes were not successful. Only when the battery is located on the frame I can get good handling. It's of course visually not that appealing but that's the least of my concern as I don't want it to be stolen. (I'll park it outside)

ps: Tonight I'm thinking to bring this bike to london so hopefully it should be all working and functional by then (I don't have the tool to repair in london), so if you see something that needs to be corrected please tell me

 

[mountainsport]

my bike is almost complete:

Thanks to d8veh I've now a rear disc brake which is super nice.

I've placed the batteries on the frame for balance. It's a big battery of 72v20ah ahah, almost 1500wh. I'm cycling them to see how they perform

Hi cwah, what a mean machine, awesome I like it . The big question is do you have a special run way to handle that power ?

MS.

 

[cwah]

Run way to handle that power? You mean autonomy?

I'm now bringing my bike to london. I'm so excited. The dahon jetstream rolls well when folded, I'm quite happy about it.

Fingers crossed I won't have any reliability issue in london as I don't have my tool box now in london!

 

[cwah]

bike finalised. Stealthier. The best I can do without drilling the frame: