2 wheel drive DH bike build (Delta/Wye Upgrade)

So I guess it's time for me to start a build thread.

First: The bike.


I've had the bike for a few months and put a 1000 miles on it and I'm happy with the way it performs.


It's an Ibex brand Ignition Sport model. I went to their website today to see what they had left of the 2009 models and found this:

IBEX Bicycles has closed.

Look for the IBEX brand to re-open under new management in 2010.
Sorry, no additional information is available at this time.

Good thing I bought one when I did...

Second: The motors.

I ordered two of the "cute" motors from bmsbattery which should ship out on Monday. I made the mistake of using an E-check to pay and that took four days to clear or I would already have them.


They are the 48 volt 500 watt version of the 128mm diameter motors. I ordered them with the disc brake option and hall sensors. They will be going on 26 inch rims.

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Well, after trading emails with my contact at bmsbattery I ended up with a different pair of motors. It seems that the 128mm motors will not fit even a 6 speed in a 135mm dropout so I opted for the 100mm motors instead. But what they actually sent me were a pair of QX85 motors, one front and one rear.

These motors did fit an 8 speed freewheel and disc brakes on front and rear with only a very small amount of spreading for the washers so I am happy with that. The stickers on the motors say 350 watts and 48 volts.

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I was going to attempt the wheel builds but I found a good LBS that will do it. I added the bike shop to JasonEBK's Ebike friendly database website. It's called Blue Star Bikes.

Third: The controllers.

I'm leaning toward getting a pair of controllers from bmsbattery as they seem to have some nice features on them but haven't decided yet.

Fourth: The battery.

That's the tough one, I will either need something like 48v 10ah with a high C rate. Or 48v 20ah with a modest C rate to run both motors. I could also go with two 48v 10ah of lesser C rate and that would give me redundancy in the batteries like the rest of the system. Most likely I will have the battery/batteries in my backpack and not on the rack.

Advice in any or all of these areas is greatly appreciated.

Gary

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BUILD COSTS
IBEX Ignition Downhill Bike: $738.95
Motors and Controllers: $279.93
Turnigy Watt Meters: $68.85
Throttles and Freewheels: $64.98
Spacers, C Washers and Freewheel Removal Tool: $57.00
Rims and Fenders: $90.01
Batteries: $800.04
Torque Arms, Lights, and Connectors: $ 235.07
Tires and Tubes: $ 141.63
Two Wheel builds: $142.00
New Rear Shock: $189.00
Total So Far: $2807.46

*********End of Edit********

Looks like an interesting build and i plan to do something quite similar myself in the near future, so make sure to give some regular updates

Torque Arms.


And put the batteries in the frame (build a headway pack to suit). In the backpack gets heavy after a while, and the connection is annoying....but it's better than a rack, which will RUIN the handling completely.

Mark_A_W said:

Torque Arms.


And put the batteries in the frame (build a headway pack to suit). In the backpack gets heavy after a while, and the connection is annoying....but it's better than a rack, which will RUIN the handling completely.

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What he said ^^^

Go to ev components and look at their 48/10 headway pack. The 48/20 won't fit into the triangle.

Let me add a bit more info before I reply to your posts.

Weight: Me -- 135 pounds
Bike -- 40 pounds in its current configuration

Commute Distance: 45 miles round trip. When I head to work I do about 5 of the 22.5 miles on my bike and the rest on buses. Going home it varies from 5 miles up to the whole 22.5 miles on my bike. Since I already pedal these distances I will continue to pedal after the conversion so my range should be good even with minimal batteries.

Budget: Not counting what I already spent I can do about a 1000 bucks which should be plenty.

Looks like an interesting build and i plan to do something quite similar myself in the near future, so make sure to give some regular updates

Click to expand...

I'll try to add something a couple times a week. I'd love to hear your plans if you want to post an overview of what you want to achieve and what parts you are looking at.

Torque Arms.

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Yeah, don't want to forget those. I plan on using two torque arms on each axle or two custom made torque plates on each. The rear dropouts are very beefy but the fronts may need modification. I've read enough stories on here about snapping dropouts to make sure I give this plenty of attention.

And put the batteries in the frame (build a headway pack to suit). In the backpack gets heavy after a while, and the connection is annoying....but it's better than a rack, which will RUIN the handling completely.

Click to expand...

I don't want to build a pack at this time because I know it would take quite a while as I have very little tinkering time at present. That would be the idle solution but I think that will have to wait for when it's time to do upgrades.

Go to ev components and look at their 48/10 headway pack. The 48/20 won't fit into the triangle.

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Thanks for that I didn't know about that site or their headway packs. I did some measuring and even the 10ah pack won't fit in the triangle but that pack looks really good. 6C max rate is more then enough for running both motors and it's pretty light. I'm putting that pack to the top of my battery list.

I know of 1 company that does a dual controller but don't know any details but have had a few controllers off them and been in contact with the sales lady there and she was real helpful, she went by the name of Kitty. Can forward her email if you drop me a PM. I'll likely be looking into 1 of these in the not too distant future as it should mafe the interfacing easier than 2 seperate controllers.
http://www.lsdzs.com/e/Pro.asp?classid=2

I haven't used this model but have a 25A 500W at 36V rated controller from the above company. It was current limiting initially when used with my 500W at 36V motor geared hub motor, but I think that motor rating is very conservative. It's not 1 of these "cute" motors before anyone gets too excited. It weighs 4 kgs, but it's pretty strong and accepts disk brakes. Sent the controller back and they adjusted something and it's functioning pretty well, at 48V now

I've got a few of these cute motors and got 3 different MTB, 2 hardtails and a full suspension on there way. The Hardtails will likely be prototypes for a future project but the full suspension will be my plaything I reckon 2 overvoltaged cute motors should be quite interesting or maybe even 2 of the bigger bad boys in there Now that really would shift. Might have a play with putting some smaller rims in there too. Presently got some headways lined up too, it's all good 8)

lynchy said:

I know of 1 company that does a dual controller but don't know any details but have had a few controllers off them and been in contact with the sales lady there and she was real helpful, she went by the name of Kitty. Can forward her email if you drop me a PM. I'll likely be looking into 1 of these in the not too distant future as it should mafe the interfacing easier than 2 seperate controllers.
http://www.lsdzs.com/e/Pro.asp?classid=2

Click to expand...

Sorry, meant to reply sooner but got distracted. I did see that controller but I'm going with two small controllers for redundancy although that looks like a good option too.

I've got a few of these cute motors and got 3 different MTB, 2 hardtails and a full suspension on there way. The Hardtails will likely be prototypes for a future project but the full suspension will be my plaything I reckon 2 overvoltaged cute motors should be quite interesting or maybe even 2 of the bigger bad boys in there Now that really would shift.

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What you are planning sounds good, especially the over volting. I won't over volt mine to start with but may do that after i see what kind of performance I get out of a conservative setup.

Update: I just saw this on the Turnigy watt meter for 25$ thread: They are back in stock.

I zipped over to the Hobby King website and ordered 2 for this build. 8)

If you're gonna stick with standard power you might want to consider getting hubs for a smaller rims. These motors are designed for EU where 15mph is max and 250W. They are geared so that they will only do just a little over that, maybe 17 or 18mph and that's your lot. This gives them the best possible acceleration for what they are but means they will not give any assistance at higher speeds if you pedal. The controller should be limited electronically to 15mph in Europe also, so the fact that the motor is mechanically limited to little more than the legal limit is immaterial.

If you're going for 2 hub motors I'd consider a higher revving motor if you're sticking with standard voltage. I know the motor for 20" rim spins to about 290rpm roughly (got 1 here (24V) so I'll try to get around to checking that) and having 2 will overcome the lack of torque. I personally reckon overvolting from 36 to 48 and sticking with the 26" rim motor would be pretty good.

By the way, my dad checked a 108 front motor I sent him, it's the wider type, without disk, and it came in at 2.4 kgs. The narrower front motor with disk is a bit lighter. Will get some scales tomorrow and give the weights of each type. Apologies that I'm so ill prepared, I only brough 2 suitcases when I moved to China from Korea a few months back. Just getting a descent set of tools and test kit together now. I'll get there in the end

lynchy said:

If you're going for 2 hub motors I'd consider a higher revving motor if you're sticking with standard voltage. I know the motor for 20" rim spins to about 290rpm roughly (got 1 here (24V) so I'll try to get around to checking that) and having 2 will overcome the lack of torque.

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I was thinking the exact same thing when I found out I couldn't get one of the 128 rear motors that would squeeze into 135mm dropouts and had to switch to the 108. My order still hasn't shipped as far as I know so I'm still considering doing just that.

I have no problem pedaling up to say 10 or 15mph and then let the motor take most of the load. I realize I'm trying to make this bike for commuting long distances and be a fun off road toy too. I think it will work out better if I reserve this one for commuting only and then build a trail bike next year that has lots of low end grunt if I still want that.

Sound reasonable?

Sorry didn't see your post before. AFAIK the 26" rim type motor maxes out at about 200rpm and the 20" rim motor is about 290rpm. I don't know if there's another option in the middle. Will try to find out soon.

I'm hoping to put 2 of the 108 motors in my POS bike soon and will definitely be putting double motors in the dual suspension bike that will hopefully arrive within about 10 days. I've only got 1 piece of 20" motor and it's a 24V so cannot check the configuration you're suggesting, ie double high revving motors. I reckon overvolts from 24 to 36V might be a bit much, and 36 to 48V would be a safer option IMO just because you'll be dumping more power into a 24V running at 36V, than you would on a 36V motor running 48V. Also overvolting at the higher voltage will be an easier load on the battery I reckon. If you're likely overvolt, I'd recommend sticking with the 26" type motor.

I found the 26" motor, which aparently has a 9:1 reduction ratio has a kind of resistance when you pedal with the motor assistance. The 20" motor should have a lower reduction ratio and I'm curious if this will effect this resistance that I have felt and it should give assistance to a much higher speed, which is nice. The 26" motor had pretty good acceleration for what it is (a 250W nominal motor). I'm curious to see how the acceleration is effected by putting a 20" motor in a 26" rim and also how fast it will go on motor power only. I will try put the 20" (front) and 26" (rear) motor, both in 26 rims and see how they compare, back to back. Will have to try to get some way to actually measure the real acceleration, rather than just using my butt dyno

I've been informed that the 108 motor is the superior motor, for what it's worth, but have never used 1. I would take the specs they claim on the motors with a pinch of salt. I do not believe that any of these motors are rated more than 250W nominal but do have a power plot which indicates a peak power of about 400 to 500w on the 108 motor. The small difference in cost that I remember you quoted doesn't reflect the difference in wholesale price IMO, so the 108 has a lower percentage markup I reckon.

Will try to pull apart some of these motors soon. The weekend ended up very very busy but also very productive. Got a new apartment lined up that is about 3 to 4 times the size of the place that we're presently staying and it costs only about a 1/3rd more in rent. 1 room for storage and another room for workshop, bliss The space I've had and the facilities I've had for the last few months has made things very difficult and would be impossible in the future. My girlfriend is good but couldn't see her putting up with the new additions to the test fleet that will be here soon :lol:

Thanks for all the advice Lynchy. I'm going with the 108mm motors for 26 inch rims and disc brake capable on both. Hope they end up fitting OK. Not sure why but it's taking them quite a while to ship out my order...

Finally received some parts for the build . My two Turnigy watt meters showed up on Friday and they look great. Now I need to figure out how I want to mount them. I think the controllers will be mounted on the top tube with one meter next to each although I will have to look down to read them. Not sure if I have room for bar mounting them but that might be safer. Time to get out the tape measure.

I'm rethinking my tire choice as the Continentals I'm using aren't quite what I need. They are the Town and Country version with a bit too much slick for my type of riding. They do OK on clean pavement whether its wet or dry, but not so good off road in mud or wet grass. The puncture resistance is horrible too.

I'm leaning toward one of the Armadillo type Specialized tires although my top choice in tread doesn't have the Armadillo option. I guess I could put some of those puncture strips in them as I would rather compromise a bit on flat protection and get the handling I want.

why do you want dual motors?

monster said:

why do you want dual motors?

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Because I'm way too cool for just one 8)



OK, here's my thinking on that:

1. Weight distribution. The handling should be better with two small motors, one in each wheel, as opposed to one larger in front or rear. (One small motor will be too wimpy in my estimation)

2. Redundancy. Dual motors and controllers, and later dual batteries, should make it less likely that a breakdown will keep me from having assist. (Yes it's also more parts and connections to go bad)

3. All Wheel Drive. Should aid in traction and handling. (Yeah you get that with a front motor and pedaling also. Not having to pedal for it is better :wink: )

4. Bragging rights. "Oh you have a motor on your bike? I have two."

An excellent project that I'm certain to be watching. Two small geared motors make a lot of sense if you want really good low-end torque. I would do a dual set-up myself, and still might, however none of my batteries is up to delivering enough current. The low cost of the motors and controllers from ecitypower/bmsbattery also make it a pretty inexpensive project.

The simulator at ebikes.ca doesn't have any geared motors smaller than an eZee but I still find it useful to use the eZee as a stand-in for one of my 250W motors keeping in mind that I need to adjust the results down by perhaps 20%. Anyway if you pit two eZee geared motors running at 20A against any other single motor running at 40A the dual motors comes out on top by a good margin. For example dual eZee's at 36V/20A/26" will produce a combined thrust at 0mph of 90 pounds and at 15mph it's 36 pounds. Compare that against the BMC V2-T at 36V/40A/26" which generates 78 lbs of thrust at 0mph and 24 lbs at 15mph. Top speed of both set-ups would be 21-22 mph. Then compare the dual eZee's to a single X5305 at 36V/40A/26" which produces 52.5 lbs of thrust at 0mph and just 18 lbs at 15mph. Of course dual Cute's or Bafangs won't be quite as strong as the dual eZee's but you can pick up two of Cutes or Bafangs for less than the price of a single eZee motor.

I do think picking the right RPM motors for dual project is important, as it always is. My present bikes both use small geared motors, the first is a 36V Bafang (~6.4RPM/V) which I run at 48V, the second is a 24V GM Mini (really a Bafang/~9.1RPM/V) which I run at 36V. Both of these set-ups produce essentially the same flat road top speed (~23 mph/250 lbs total /700C wheels) but the 36V motor at 48V has better low-end torque. The 24V motor on the other hand will do 29 mph on 48V/20A though that power level can quickly overheat it; in fact I melted some hall wires on the 24V mini pushing it hard at that level.

As somebody previously mentioned I would also be inclined to go with the higher speed/lower torque motors for a dual set-up unless monster low end torque is what you're after; for me that would mean adding another 24V motor to the bike with the 24V front motor though I probably would continue running it at 36V. The top speed would likely increase 1-2 mph to 24-25 mph and with the motors sharing the load they could cruise flat out for long periods without overheating yet they would still offer more low-end thrust than most single motors.

-R

Two wheel drive definitely rocks, that's why 3 of my 4 motors are front hub. Since I like to pedal, I simply pedal the rear wheel. There are limitations in rough terrain though, since you start losing traction on a front wheel going up a steep hill. But a heavy front wheel does avoid another problem you get when it's really steep, like 20%. At some point on a rear wheel bike, you start having a serious wheelie problem.

I really really like front hubs on the street though, since you can power through a corner with both wheels grabbing traction. My town has just about all the wheelchair ramps done on the sidewalks, so I don't need to pop over curbs any.

Same reason I started my project with these cute little motors. Its not energy efficent to run 2. you're doubling your parasitic losses, BUT you're gaining extra traction and balancing the weight, plus the cool factor.

Graycard, I put some pics of the insides of the 108 motors on the cute thread. By the way the front 108 motor with disk is only 2.05kg. The rear that I have here with the very long axle and which is the wider 100mm type is just under 2.4kg. Both these are disk compatible.

Russell said:

Then compare the dual eZee's to a single X5305 at 36V/40A/26" which produces 52.5 lbs of thrust at 0mph and just 18 lbs at 15mph.

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that may not be the best comparison since most folks would choose a higher KV motor than the 5305 to run at such a low voltage, such as a 5302 or 5303. 5305 is wound for high voltages, such as 72 volts, so performance at low voltage is not so good @36v. A 5305 on 36v is like having a V-8 that runs on 4 cylinders.

...but I get your point.

The simulator at ebikes.ca doesn't have any geared motors smaller than an eZee but I still find it useful to use the eZee as a stand-in for one of my 250W motors keeping in mind that I need to adjust the results down by perhaps 20%. Anyway if you pit two eZee geared motors running at 20A against any other single motor running at 40A the dual motors comes out on top by a good margin. For example dual eZee's at 36V/20A/26" will produce a combined thrust at 0mph of 90 pounds and at 15mph it's 36 pounds. Compare that against the BMC V2-T at 36V/40A/26" which generates 78 lbs of thrust at 0mph and 24 lbs at 15mph. Top speed of both set-ups would be 21-22 mph. Then compare the dual eZee's to a single X5305 at 36V/40A/26" which produces 52.5 lbs of thrust at 0mph and just 18 lbs at 15mph. Of course dual Cute's or Bafangs won't be quite as strong as the dual eZee's but you can pick up two of Cutes or Bafangs for less than the price of a single eZee motor.

Click to expand...

That's another thing I was thinking that 2 wheel drive might provide but didn't include in my reply as I haven't seen any real world head to head tests to confirm it. Will they really give more thrust at a given wattage? Will they be more efficient with less load on each motor? Less heat buildup?

I will try to gather as much data as a can to see if we can spot a trend. It will be nice if there are other pluses to going this route.

dogman said:

I really really like front hubs on the street though, since you can power through a corner with both wheels grabbing traction. My town has just about all the wheelchair ramps done on the sidewalks, so I don't need to pop over curbs any.

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I'm really looking forward to that part. Being able to power through a corner and maybe doing some controlled skidding

I'm still going to be jumping up and down curbs so I hope these little babies are up to it. I'll keep the speeds low to start with in case I snap an axle. I can't wait to try it off road too!

I'm liking the lack of any skidding when I blast a corner with both wheels grabbing. But I know what you mean, when I was young, I'd go out on a rainy day looking for painted stripes on crosswalks for the slide.

Out in the dirt, I find the 2wd really helpfull in the soft stuff, sand or loose dirt. One wheel may spin in the sand hole, but if the other wheel grabs you keep going. I have the fusin front hub, but with more battery, I do think about a dual drive, maybe 9c on the back. I'd want independent throttle controll of both motors. It would get so heavy though, ya might end up doing the lipoly backpack to carry some of the battery.

Ordered a few more parts for the build.

I have a 6 and 8 speed freewheel, and a thumb and twist throttle coming from Cycle9.

I figured if I can't make the 8 speed fit I will go with a wide range 6 speed so I still have my granny low gear. I will use a twist throttle if I can go with my current indexed shifter and 8 speed. But if only the 6 speed fits I will have to get a 6 speed shifter and the only one I've found that I like is a grip shift version. So that means a thumb throttle.

From Jenson USA I purchased new chainrings to replace the cheapo ones that came on the bike. I also ordered some brake pads and a set of rotors from them.

On the chainrings the originals are 22t, 32t, 42t. I'm replacing them with 22t, 34t, 48t. That should give me a better top end with the new 6 or 8 speed that both have a 14t small. The current freehub on the bike has an 11t small. The extra rotors are an upgrade from what I have plus I can leave the non motor wheels intact for backups.

Still have lots to order.

Torque arms, battery, charger, brake levers with cutoff switches, freewheel spacers, freewheel removal tool, and maybe a 6 speed shifter. I know where I'm going to order most of this stuff I just need to sit down and do it.

will_newton said:

Russell said:

Then compare the dual eZee's to a single X5305 at 36V/40A/26" which produces 52.5 lbs of thrust at 0mph and just 18 lbs at 15mph.

Click to expand...

that may not be the best comparison since most folks would choose a higher KV motor than the 5305 to run at such a low voltage, such as a 5302 or 5303. 5305 is wound for high voltages, such as 72 volts, so performance at low voltage is not so good @36v. A 5305 on 36v is like having a V-8 that runs on 4 cylinders.

...but I get your point.

Click to expand...

I chose the X5305 to make the comparison as even as possible selecting motors that had top speeds in the same range, 21-22 for the eZee and BMC V2-T and about 19 mph for the X5303. The next step up, the X5304, might have been a better choice with a top speed of about 23mph at 36V/40A/26". The X5304 would generate lower torque at 0mph (51 lbs) than the X5305 but more at 15mph (29 lbs) but again these would be less than the dual eZee's at 36V/20A/26" at 90 lbs and 36lbs respectively. The comparison was an exercise showing the low speed thrust which can be achieved using two smaller geared motors compared to a single motor while keeping the voltage and total current the same, I was not suggesting someone would necessarily want to build an X5/36V system.

-R

The stuff from Cycle9 came in yesterday. I ordered on the 21st. Got an email updating the status as shipped on the 22nd, which was a Sunday. Then received it Wednesday morning the 25th.

Great service, and it was the free shipping, as the order was over $50 dollars. The items were well packed so they arrived in perfect condition. They are also great about answering emails promptly.

Now if I could just get my motors and controllers from BMSbattery. They still haven't shipped.
They have been good with communication though so I'm not worried, just getting a bit impatient. I'm even considering getting one of their batteries...

Ordered rims and some fenders.

The rims are Alex TD17 26" 36 hole disc only. They are designed to help prevent pinch flats but I have no idea if they really do. They look pretty strong so I hope they will hold up to my abuse. $21.20 each from Niagara Cycle Works.

The fenders are Topeak Defenders M1 and M2. The reviews say they won't hold up to off road use which is OK as I just need them on the street when it rains. They can be put on and taken off quickly without tools. The down side is they may not even hold up to curb hopping without reinforcement. Also ordered from Niagara.

Still waiting on my motors and controllers which still have not shipped. My patience is about gone with BMSbattery at this point. Not only due to this delay but also due the fact that I was asking questions about their batteries and they didn't seem to know what I was talking about. They then quoted a price that was $72.00 more than what the pack was selling for on the website...

I'm almost ready to cancel the order and get a couple of GM mini motors instead.

Gary