new-old build

[gwhy!]

My son in law came around today and asked if I can make his cycletrials electric ( the has the same fame as my current bike ), As I have most of the stuff on hand from playing around with developing my bike it should be quick to fit together so I thought I would put the build on here.

The Bike:

flea.jpg (115.31 KiB) Viewed 1826 times

I was going to use this on my bike but it looks like he have now got it

Handle bar stem jackshaft1_.jpg (36.44 KiB) Viewed 2015 times

Just testing the fit:

Handle bar stem jackshaft2_.jpg (95.18 KiB) Viewed 2030 times

Modding the Kart (small )engine sprockets ( steel hubs needed to be made that will be welded in )
I know he will only need 1 but thought I will do the 2 that I have ( a 10t and a 11t )

kart engine sprockets.jpg (45.46 KiB) Viewed 2030 times

The Rear Kart sprocket carrier was turned down to a sensible thickness ( I done this ages ago and have never used it ), There is room to also put a freewheel on the wheel hub but as the son in law dont want a peddle chain I havent bothered ( my bike has one though and working peddles )

kart sprockets.jpg (50.83 KiB) Viewed 2030 times

And as this is a freebee for him he is getting my very first rc motor I dont know what it is but I think it was rated at 2kw and 200kv, these pictures are just showing how I mount the motor and jackshaft on the seat tube.

motor mount.jpg (133.7 KiB) Viewed 2015 times

Anyway thats it for now. I will put more pics up as and when I do more to the bike.

[spinningmagnets]

Fantastic! do you have a link for the stem, bearings, motor, and pulleys? Those stems are a great value for how stong they are and how professional they look...

[Hillhater]

Is this it ? AZONICS "Equaliser Stem" ...Au$29.0
http://www.chainreactioncycles.com/Mode ... delID=3907
""Taking our stems to a whole new level of performance. Super stiff design, machined from a solid billet of 7000 series Alcoa® aluminum and internally bored to save weight.""
Features:
• Precision CNC machined from 7000 series T6 solid billet.
• 6-Bolt face clamp hollow plate design.
• 3-Bolt steerer clamp.
• All cromo mounting bolts.
• Hot anodized Finish with laser-etched graphics.
• Available in 40mm, 50mm & 60mmm extensions.
• Available in standard 25.4mm
• Weight: 220g (50mm OS 31.
• Rise: 0°-5°
• Stack height:48mm
• Material: Alcoa® Aluminium
• Steer Tube:1.1/8

[gwhy!]

Here is the rear sprocket setup on my current bike, its has some tabs welded onto 2 large sprockets from a 7 speed cassette that was dismantled and then reassembled in a different order to give the correct spacing and chain line. Then my home brewed broached freewheel was then added onto the freewheel hub.

pic without additional freewheel

rear sprocket right.JPG (45.6 KiB) Viewed 1809 times

pic with additional freewheel

cheap sprocket adaptor.JPG (47.19 KiB) Viewed 1809 times

Home brew splined freewheel:

freewheel1.jpg (76.85 KiB) Viewed 1998 times

[gwhy!]

Fantastic! do you have a link for the stem, bearings, motor, and pulleys? Those stems are a great value for how stong they are and how professional they look...

Yes the stem is really nice and very good value for the money ( thanks Hillhater for the link ), the bearings are standard bearings 12mm Id 28mm od there is a ~.5mm tubesleave ( just a bit of very thin steel sheet cut with tinsnips then shaped) that the bearings are in within the headstem. I cant remember where i got that motor from but they sell what looks like very similar one at hobbyking.

[boostjuice]

Nice work! Where are those nice lightweight looking pulleys from?

[gwhy!]

Nice work! Where are those nice lightweight looking pulleys from?

The pulleys are from http://www.bearingboys.co.uk/ But I took quite alot of ali off of it to lighten it, I made it a lot thinner in the lathe then drilled some big holes though it.

[boostjuice]

Ahh.... i thought it came that way from the supplier. It seems like self lightening is the only option to get the unnecessary weight out of alloy pulleys. All of the off-the-shelf ones I have found are fatties essentially cut straight from pulley stock.

[ev_nred]

nice looking build! may I ask where you got the sporkect from? thanks

[gwhy!]

nice looking build! may I ask where you got the sporkect from? thanks

The rear sprocket is a kart sprocket ( #219 ) and theses are widely available ( and cheap ) and the sizes are from 60t upto around 100t the front sprockets are a little more tricky 10t upto14t but these also can be bought from karting online stores but will need modding to be able to fit to a shaft.

[gwhy!]

While I am at it here is another way of fitting 2 freewheels onto the rear wheel:

2xfreewheels.jpg (78.81 KiB) Viewed 1779 times

Screw first freewheel onto the wheel hub:

freewheel1 without cup_.jpg (64.02 KiB) Viewed 1590 times

Use a bottom bracket cup:

Bottom bracket cup.jpg (61.91 KiB) Viewed 1590 times

Screw bottom bracket cup into the remainder of the threads of the first freewheel:

freewheel1 with cup screwed in.jpg (57.48 KiB) Viewed 1590 times

Then screw the second freewheel onto the BB cup:

fitted freewheels.jpg (55.94 KiB) Viewed 1779 times

This proved to be very strong and a very easy way of fitting 2 freewheels onto the rear wheel, it has been shown may times on this forum and is by no means my idea but it works a treat

[gwhy!]

Back to the build :
I fitted one of my old hall sensor to the motor plate.

motor with hall sensors.jpg (112.73 KiB) Viewed 1794 times

[spinningmagnets]

I'm glad you brought up the BB-cup as a coupler again, Gwhy. The builds being put together by Matt, AJ, Thud, and others are very high-powered (I love their work!), but many low & mid-power builds would benefit from this.

Here's the thread about that with lots of pics and part #'s to make ordering a new one easier ($4-$20, plus shipping and handling?)

http://endless-sphere.com/forums/viewtopic.php?f=28&t=13862&p=206189

http://www.niagaracycle.com/product_info.php?products_id=10308

[gwhy!]

I'm glad you brought up the BB-cup as a coupler again, Gwhy. The builds being put together by Matt, AJ, Thud, and others are very high-powered (I love their work!), but many low & mid-power builds would benefit from this.

Here's the thread about that with lots of pics and part #'s to make ordering a new one easier ($4-$20, plus shipping and handling?)

http://endless-sphere.com/forums/viewtopic.php?f=28&t=13862&p=206189

http://www.niagaracycle.com/product_info.php?products_id=10308

I agree its got to be the easiest/cheapest ways to achieve peddle isolation, high mid powered is fine I was putting upto 4kw through this setup and there was no signs of it ever failing.

[full-throttle]

I really like the way you're using the sprocket carrier and the stem - the less custom parts the better IMHO

Roughly, what does the rear sprocket assembly weight?

[gwhy!]

I really like the way you're using the sprocket carrier and the stem - the less custom parts the better IMHO

Roughly, what does the rear sprocket assembly weight?

Sorry FT I haven't answered this earlier, I havent weighed them but a guestimate would be <300g ( I will weigh them properly when I take it off again ).

I have done a bit more to the bike today ( not much but a little ) made and fitted a chain director/tensioner...

driveline1.jpg (116.88 KiB) Viewed 1066 times

Also fitted one of my hall sensor blocks to the motor mounting plate.

[gwhy!]

Thought I would just do a quick update on this build.
The bike is finished And tootals along quite nicely at around 35-40mph , I have replace the purple motor with my other 3250w 170kv motor ( and to be honest its to fast for the bike geo, but son inlaw likes it). I have limited the current on the controller to 50A so the whole setup will only draw a max of around 2kw @44.4v but this seems to be fine and the bike pulls away without any problems on a 10-15% grade hill it gets to top speed in around 3-4 secs which Im quite pleased about , the bike has no working peddles so the pulling away needs to work well, and it does. When I get the chance I will take some pics and video of the finished bike if anyone is interested.

[deVries]

When I get the chance I will take some pics and video of the finished bike if anyone is interested.

Great work & results!!!

Yes! Of course, no ifs, ands, or buts, we want to admire your work in stills & motions... like last year!

(Happy New Year )

[gwhy!]

Ok here is another update, I had a phone call from son-in-law saying that the bike cuts out and do not have any power... The only thing that have changed was he fully charged the battery ( when I was testing the bike the voltage was at around 46v max ) so he brought it back to me to have a look at. It was cutting out and would not pull away under its own steam . This was down to initial phase current ( because of the initial higher start voltage and the cutting out problem found on these 6 fet controllers ) the solution was to re-gear the bike for around 25mph ( as I didnt have a quick fix, to gear for around 30mph to try ) but now fine on a fully charged battery ( 50v ) but he is not happy because of its slower top end so now he wants me to find a solution (if only life was that simple ). The lesson learnt here is that its very important not to gear any bike to high for the controller, which I already knew but this confirms this.. we need a better controller,,,, don't we Jeremy

[deVries]

It was cutting out and would not pull away under its own steam . This was down to initial phase current ( because of the initial higher start voltage and the cutting out problem found on these 6 fet controllers ) the solution was to re-gear the bike for around 25mph... The lesson learnt here is that its very important not to gear any bike to high for the controller, which I already knew but this confirms this...

That's not exactly the update we were hoping for.

When you get the bike fixed/upgraded again use the video camera, and please shoot some video of motor/gearing close-ups & bike going from 0-30mph.

Trying to read between the lines here for my way of understanding, wish I knew more ... The phase current was going too high off the initial start, because the gear was not low enough to increase the torque high enough for the initial start? And when this happens, it kicks-in some sort of "overload" or protection circuit that prevents it from firing the motor, because the phase current is over its limit, overloaded? So, the lower gearing allows for lower initial phase current, because the torque is higher lowering the loads on the initial start-up phase currents.

Is there no way to program the controller to limit this problem? Would beefing up the shunts address this problem?

I vow to one day understand most of this!!!

[gwhy!]

Yes, this is what I think was happening and reducing the gearing solved the problem. The 6 fet controller that I am using is all tweeked as far as it can go with the current fets that I have installed ( I dont think it will last to long if pushed any further with the built in initial current shutdown ) . The bike would still run but it would need a little push off and the throt had to be wound up very carefully or it would shut down but at least it didn't let any magic smoke out. I will get some photos and video to upload soon. I still have the bike here now so I may try it again with a lower voltage and swap the gearing back again just to see if it was due to the difference in voltage as it was a bit odd that it work perfectly until the battery was recharged..

Edit: the controller is still limited to a battery current of 50A and phase of 120A I may just try and up this to the same as my bike ( 70/170) just to see if will help.

[LI-ghtcycle]

Wonderful build! Thank you for all the info here!

Maybe I missed it somewhere in the post, but what is the current gear reduction that is limiting it to around 25 MPH? And what are the sizes of the chain rings on the rear wheel, jack shaft and motor is you could please?

Thanks!

[gwhy!]

Wonderful build! Thank you for all the info here!

Maybe I missed it somewhere in the post, but what is the current gear reduction that is limiting it to around 25 MPH? And what are the sizes of the chain rings on the rear wheel, jack shaft and motor is you could please?

Thanks!

Thanks LI-ghtcycle,
The rear chain ring is a #219 kart sprocket I think its a 75t, the sprocket on the jackshaft is 11t, the motor pulley is 18t to a 72t pulley on the jack shaft It has 26" wheels and is running a 170kv 3250w motor @ 44v ( 50v hot off the charger ) The 25MPH is when the bats at hot off the charger.

[dbaker]

Yes, this is what I think was happening and reducing the gearing solved the problem. The 6 fet controller that I am using is all tweeked as far as it can go with the current fets that I have installed ( I dont think it will last to long if pushed any further with the built in initial current shutdown ) . The bike would still run but it would need a little push off and the throt had to be wound up very carefully or it would shut down but at least it didn't let any magic smoke out. I will get some photos and video to upload soon. I still have the bike here now so I may try it again with a lower voltage and swap the gearing back again just to see if it was due to the difference in voltage as it was a bit odd that it work perfectly until the battery was recharged..

Edit: the controller is still limited to a battery current of 50A and phase of 120A I may just try and up this to the same as my bike ( 70/170) just to see if will help.

Is your controller a 12 fet (70/170)?

[gwhy!]

Yes, this is what I think was happening and reducing the gearing solved the problem. The 6 fet controller that I am using is all tweeked as far as it can go with the current fets that I have installed ( I dont think it will last to long if pushed any further with the built in initial current shutdown ) . The bike would still run but it would need a little push off and the throt had to be wound up very carefully or it would shut down but at least it didn't let any magic smoke out. I will get some photos and video to upload soon. I still have the bike here now so I may try it again with a lower voltage and swap the gearing back again just to see if it was due to the difference in voltage as it was a bit odd that it work perfectly until the battery was recharged..

Edit: the controller is still limited to a battery current of 50A and phase of 120A I may just try and up this to the same as my bike ( 70/170) just to see if will help.

Is your controller a 12 fet (70/170)?

The controller is a Modded 6fet.