Crystalyte HT 3525 Intense Uzzi

C

chefkoch

1 mW
Joined
May 17, 2011
Messages
19
Hi, I am a motorbike enthusiast that does more and more mountainbiking since the offroadbikes are not very wellcome here in Switzerland... So I decided to build my first ebike :)

After some time of reading and simulating i went for a Crystalyte HT 3525 at 72V (20s Lipo).

The bike is a Intense Uzzi 2002:
IntenseUzzi.jpg
It was chosen because of its special frame that has some space for the batteries.

8*zippy flightmax 4.4Ah from hobbyking (20s 2p) just fit into the frame:
Akkus.JPG
The accuframe is just 85mm wide, was made out of 2mm aluminium and 1.5mm for the sidecovers.

The motor was modified (cable guard, bearings, helicoils for the breakdisc…) and equipped with sensors by http://www.electricwheels.de.
Additionally I drilled some 24mm holes in the left sidecover to add some ventilation…HT35.jpg
Had to adjust the 180mm disc since the motor wobbles a bit…

The controller is a crazyman 40A 72V.Controller.JPG

Actual setting is 25A and 66A phase current for testing. So about max. 2000W on the motor.links.JPG
rechts.JPG

The bike runs well, its really fun to drive. Vmax is about 55km/h with fully charged batteries.
It weights 29.7kg. The range is a bit limited, I've just done 28km at max. But this was often in full throttle mode, since it wheelys very well, allmost like a motorbike but with the security of the rear break at the handlebar :)

cheers Löru
 
Hi Loru,

Nice build mate and welcome to ES :D

I am enbarking on a similar build with an Intense M3, 20s and a HT3525 and am curious to find out more about its wheelying ability
(also a dirtbike rider - '08 Husky TE250).

Does it just wheely from a standing start or can it do it at certain speeds? If it can do it while already moving, do you need to help it with pedalling?

Are you planning on upping the current for more torque or are you happy to keep it at 2kw? I'm planning on 4kw peaks but will need to monitor motor temp closely.

Also, how do you find it's climbing ability with the 26" wheel?

Great work :mrgreen:

Paul :D

Edited twice 'cos i seemingly can't spell lol
 
Thanks and yes I did a lot of reading in this great forum!

@Paul
There are actually 6 Huskys in my garage :) but only old stuff, CR390, TE510, TE610...

Your Intense ebike is a very nice project! A bit heavier as mine but could be have a similar weight distribution. (35% front / 65% rear)
Had to place the rear swingarm in the shorter position because the 9speed BionX freewheel needed a spacer and the big betty 2.4J touched the swingarm in the rear mounting position.
The saddle frame is also on the rear mounting position.

With 25A it does not really wheelys just with the throttle, needs an impulse at the handlebar. At speed it needs also pedalling. I find it anyway easier to hold the balance when continuing to pedal even if this would not be necessary...

But there is a big difference if the batteries are fully charged or half discharged. The 8.8Ah Flightmax 15C are perhaps a bit to weak to go higher than 25A?

With 40A and a powerfull batterie you should have no problems to pull wheelys ;)

I'm happy with the climbing ability. On the street its no problem but on steep trails its a disadvantage to have such a rearwheel seat position. Its hard to keep the front wheel on the ground..

cheers Löru
 
Hi, a short update @ 1000km:
The range is now a bit better after about 25cycles, I've done 40km max. with only moderate pedalling...
The effective power is probably also be a bit more than expected, since a mate had to reduce the SW limit to 18A to have a effective current of 25A with the same controller. So 25A limit could be about 35A effective, but I haven't measured it...
The increased speed setting (from 100 to 110%) added about 5km/h so top speed is now about 60km/h :D

cheers
 
Hi
very nice job ,
I have ordered Cry 3525 as well and a controller that just arrived ,
actually 2 sets , because I want to make a central version and a hub classical.
the final use will be on mountain rides as well .
I am interested to understand how you would compare the ebike drive , vs the Husky 250 .
do you get fun out of it or it is too weak to be compared .
I am running a Yama WR 450 enduro .

rgs Renago
 
chefkoch said:
@Paul There are actually 6 Huskys in my garage but only old stuff, CR390, TE510, TE610...
Click to expand...
Nothing wrong with the older Huskys, your a lucky man! The CR390 would be a handful i'd imagine...
I'm glad your Uzzi is running well :mrgreen:

chefkoch said:
The effective power is probably also be a bit more than expected, since a mate had to reduce the SW limit to 18A to have a effective current of 25A with the same controller. So 25A limit could be about 35A effective, but I haven't measured it...
Click to expand...
Time to get an 18fet controller and step it up to 70amps :wink: I've since found 5+kw very addictive and fun :)

renago said:
I am interested to understand how you would compare the ebike drive , vs the Husky 250 .do you get fun out of it or it is too weak to be compared .I am running a Yama WR 450 enduro .
Click to expand...
Comparison wise, they are fun for different reasons. The ebike is 35kg, the 250 (fuel injected four stroke) is 114kg full of fuel so on tight single track, the ebike is alot more manoeuverable and flickable. The 250 with its Arrow muffler isn't the quietest bike around (nor the loudest) but with the ebike being near on silent, i can enjoy trails i wouldn't dare take the 250.
The 250's suspension allows quicker speeds over rough ground, despite my ebike having 9.5" / 8" of DH suspension.
The fuel injected 250 has probably around 27kw / 6spd gearbox, the ebike about 5.5kw (peaks) and fixed gear so hill climbing and top speed are compromised in comparison. Having said that, the HT3525's torque on 70amps makes for wheely good fun and its always a buzz to trail ride a bicycle at speeds that are normally the domain of dirtbikes. Conclusion: Feed it some current and you won't be disapointed 8)

Paul :D
 
Hi

I would not really compare this with a motorbike, for that it is too weak.
You have to see it as an assisted bicycle, and then it’s quite powerful...

Its great fun driving through the woods an also on the road, pulling wheelies and so ;)
I now take often the ebike for a short ride after work when I used to take the enduro before, since the sensations of riding are quite similar…

I’m sure you will also have fun on your future ebikes ;)

Best regards
Lorenz
 
Hi Paul,

haven't seen your post when I wrote mine...

The gap between your 5.5kW Intens and a 250 4-stroke is probabely a bit smaller than my 2.5kW ebike to the 610 Husky that I ride normally ;)
But i share the same opignion what the ebike riding concerns, its quiet and therefor you better feel the silent power.

The CR390 is a restoration project, not running actually but I had a WR430 in the old days, but that's only for 2-stroke enthusiasts with all the disadvantages...

Does your HT3525 takes the 5.5kW easy or do you have to take care of the temparature?

I coud increase the power still a little but my batteries are maybe not strong enough for 50A since they are only the 15C Zippys...

cheers
Lorenz
 
Short update:
I did not recharge the batteries enough during the winter and therefore 4 packs are death. The other 4 packs could be saved and they now work in a skateboard quite well.
Since the 4.4Ah 15C Zippy’s are no more available I changed to 4Ah 25C Zippy Compact. Unfortunately they are 3mm wider than specified so I had to modify the cabling...
ZippyCompact_20.jpg
The total weight is now 29.3kg.

The batteries feel a bit stronger than the old 15C, the top speed increased also slightly, is now about 62km/h. :D
 
I finally set the speed to the maximum 120% and the current to 28A.
This added quite a lot of acceleration and the topspeed is now steady 65km/h in normal riding position :)

Then finally measured the real input current of the controller:
It pulls max. 46A which is 66% more than what was set in the SW!

This is god and bad since I have actually a 3kW instead of a 2kW ebike 8)
but the bad thing is I should probabely not increase the power any further with this controller which is rated 45A max. :wink:

values:
Condition - Current - Input power @ 80V
30km/h - 3.79A - 303W
45km/h - 11.2A - 896W
65km/h - 33A - 2640W
Acceleration Max. - 46.4A - 3712W
No load 45km/h - 1.06A - 85W
No load max. - 3.03A - 242W
Reku 40km/h - 7.9A - -632W (reku was set to mode high)
Reku 65km/h - 10.6A - -848W

The measured power at constant 30km/h and 45km/h is about 10% lower than simulated but I weared just shorts and t-shirt…

The current was measured with a 3.3mOhm shunt (a 2.5mm^2 wire 46cm long) and verified with a current clamp so the values should be quite accurate...
 
Yes you have to use an unblock sw or watch it on vimeo:
https://vimeo.com/84250453?utm_source=email&utm_medium=clip-transcode_complete-finished-20120100&utm_campaign=7701&email_id=Y2xpcF90cmFuc2NvZGVkfGI2Nzg5ZjU5ODBhZWFjNmZjNzZmM2YyNWYzMmIzNTcyMTY5fDI0Mjg1NzY3fDEzODk4MjU4NDR8NzcwMQ%3D%3D

Gruss Löru
 
No I'm not one, but thanks anyway dude :mrgreen:

It is actually much easier with an powerfull ebike than with a motorbike!
Because you have more control with the rear break on the handlebar than on the footpeg.

DO NOT WHEELIE UNTIL YOU FEEL COMFORTABLE WITH THE REAR BREAK!
When wheeling without rearbreak control it is just a matter of time and you will flip over, and that normally hurts...

Once familiar with the rearbreak it's just a matter of practice ;)

cheers
 
I balance them during charging.
All cells are wired to the charging connector and then charged with 4 separate RC chargers with 4 independent power supplies.

It is still in the provisional state, made quick and dirty ;)
 

Attachments

  • Charger.JPG
    Charger.JPG
    175.9 KB · Views: 4,548
ahh your using a pc serial connector? i have to take mine out at every charge im getting f**ked off with it to be fair, its ok with the planes because they are simply fun but my bike is my sole transport and its getting to be a chore using a balance board everyday to charge them, thanks for the pic that helped a lot
 
20170312_155850_30.jpg
 
You must log in or register to reply here.
Back
Top