Q75 Road bike results - Objective as well as subjective;

[abecrizer]

Hello, I posted on ES for the first time months ago to get advice about the best bike for my needs.
see: https://endless-sphere.com/forums/viewtopic.php?f=28&t=76292
I completed the project based on the advice I got and I want to share my results.
I will make several posts blow: 1st one with the my evaluation and results of the conversion
2nd with more detail about the parts, the conversion process and problems
3rd with a description of the context.
4th with questions for improvement (if this is better in it's own topic pls let me know).

My goals with these posts:
1) Is to provide my experience regarding what I have so others can use this info to figure
things out for themselves.
2) To show how it fit on my bike and how I solved a few installation problems.

I did a Q75 front wheel with a sine wave controller kit from BMS battery (details in 2nd post).

Subjective:
Overall I am happy with it, there are pros and cons, but the design objectives really boil down to make my bike so
I will ride it a lot instead of a litte, and this is achieved:

Pros:
-Cuts down on ride time
-I feel like I have more "reserve": I would get too out of beathe and would need to stop to rest at times without
the motor. I would feel that if a truck was about to run me over I would have no additional energy to try to get out
of the way. Now I feel like I still have a little more to give if the need arises. (Obviously I am not in very good shape, just admitting that)
-Riding seems like more of something I can do every day instead of a herculean effort that I must work up to psychologically.
-Does not take over, it assists and this feels substantial, like a heavy hand is pushing you, but it is not tempting to just let the motor do all the work

Cons:
- I think the bike doesn't look as cool with a soup can for a hub and a clunky steel fork (Vainity I know, just being honest)
- Bike is Heavier
- A little less self-satisfaction: When I did do my ride before with no motor and I crested the last hill, I felt lucky to be alive, and simultaneously like I had triumphed over some great hardship. I still feel good, but not so intensely

Objective:
I did a ride pre-conversion and recorded the data from it, and then did the same ride with the conversion so you can see the difference objectively. For some reason you have to click on this file, I can't get it to be seen inline.


*I tried to put this table in text form, but I could not get the formating right for the columns to line up,
so here is a screen shot of my spread sheet.

Explaination of the process is below:

I did the same ride both times, I stopped at the same points and measured the the above data:
The rolling time is a time my speed-o-meter counts only while the bike is moving. If I get stopped
a a traffic light, or stop because I am having chest pain, or if I stop for a beer and cigarette it will not count.
As you can see from the difference between to rolling time and the elapsed time on first ride, I stopped a lot for breaks.

The elapsed time is the number of minutes since starting the ride regardless of how many stops.

HR = Heart rate, measured from a cheapo HR moniter I have
I stopped for rest breaks several times without the motor, and never did with the motor.

I wanted to post numbers because while every response I recieved to my original post was helpful,
I could tell that there was an internal tension in ES users about their own values vs responding based on what I said I
wanted. Some people strongly recommended the q75, others said it is not worth the weight and effort to install.
I am sure both are true for those users, but I hope that these numbers will help others compare my experience to their
own expectations/desires to see if this is a good set up for themselves.

Pre=conversion bike:
View attachment 2

E-bike post conversion:

 

[abecrizer]

I got a Q75 kit with a sine wave controller from BMS battery. My experience with BMS battery was good,
though I had no technical problems or returns to deal with. I will admit I was
I was a little nervous about ordering something from China, there has been mixed experiences with BMS battery, and where I live the retail culture
is: "the customer is always right" and I do not think China has this retail culture.
I have to say I wish there was a "local" supplier. They shipped my stuff air mail, there was no other option and
it seems inefficient to ship single consumer items this way but I could find no alternative.

Every thing installed easily and worked the first time. I just got the hub motor and had a local bike shop build
the wheel. The item cost for a wheel built around the motor was cheap from BMS but because of the bulk of the rim it really jacked up the price
of shipping. So I got a better quality rim (Velocity A23) and kept a few more dollars in my home country for only a little extra cost. Also the rim matches
(close) my rear hub.


I changed my Easton EC70 fork to a boring steel one to avoid any trouble with a carbon fork from the torque. The EC70 weighed 500g (exactly)
the new steel fork weighs 1100 g, and looks less sexy. But I prefer that to dying from a drop out blow out. I do wonder if I would be ok with torque arms.

I had a few fit issues. The mount for the LCD screen is made for handle bar diameter of 25.4 mm, but my bar is 31.8 at the stem clamp.
Further more, I have road style brake levers on drop bars. The kit included brake levers for a straight mountain style bar, and that won't work for me.
Also because I have 3 hand positions available to me with the drop bars (palms on top of the brakes, down in the drops, or palms on top of the center bar portion where I have inline brake levers (thanks to this post I learned they are called "interrupt brake levers")) it is hard to find a place for the throttle.

What I did for now is just ghetto taped all that stuff onto the stem (please feel free to ridicule my lack of workmanship, I am a little embarrased about it).


I removed the return spring from the throttle so I have the option to put the throttle into an open position and put my hands on the bars where I want them. This is a little dangerous. I have hit it with my knee getting onto, off of, or while standing to peddle a few times. I intend to change this.

I primarily use the PAS sensor that came with the kit and I am very happy with it. Though I had 2 issues installing it.
There is a sensor on a bracket that should go under the flange of the bottom bracket and a ring with magnets that goes onto the spindle. It is designed to go on square taper bottom bracket spindle.

The sensor and bracket hit the inner chain ring even when no ring was installed.
I have a "power spline" bottom bracket with 3 chain rings. The ring would only fit over the splindle portion of the spindle where the crank needs to be.
As you can see my solution is as graceful and elgant as my LCD, throttle engineering. I cut the outer rind out and zip tied it to the chainring,
I took the sensor of the bracket and taped it onto the down tube where it meets the bracket shell. I had to put shims to get the right spacing without
it hitting the ring.
View attachment 1

Although ugly it does work. If you have to cut one of these rings. I cannot recommend using a hammer and chisel because the plastic
is pretty hard and it cracked either from that or from the tightening the zip ties too much. Next time I would use a hack saw or dremel.
If you choose to do this wear safety glasses: I almost lost an eye to this mis-adventure.

Other than that my only other problem is some of the cables are too long, I wrapped them around this and that, but still one time the motor cable got
into the chain rings.

I am not exactly sure about all the added weight. I tried weighing the bike before and after, but the only scale that I have to weigh something
that heavy is not too good. I have to weigh myself and the bike, and if I shift around a little it changes it a lot. It is at least 40lbs, vs 35 before,
but I think it is a lot more than that.
Battery: 5.6 lbs (2.565 kg)
Motor: 3.3 lbs (1.5 kg)
Fork 2.42 lbs (1.1 kg)

Battery is a 10.6 amp hour 36 v "water bottle" battery. It is LiPo. The charge lasted for 2 full rides, plus some little test rides. I did die at the end of the 3rd ride I made, but it ALMOST made it the whole way, and I think without those test rides it would have brought me the whole way home.

 

[abecrizer]

My situation: I commute 7 miles down hill to work and 7 miles up hill. It was taking me 45 minutes+ to do the ride at the end of the day,
and I felt like my heart would explode. Some days after doing the ride in 100+ F (38+ C) weather I would feel not too good the next day. I assumed that if it just kept at it I would get faster so I rode this way for 3 months. I did get stronger in that I did not have to stop for as many breaks, but my time improved little. My heart rate was often over 90% of my "Maximum heart rate" and many folks do not recommend training above 85% of your Max Heart Rate. I wondered if I was "over training." I am no expert on this, and in fitness circles there is a lot of controversy about this, but I wondered if that could be the issue. The American Heart Association recommends not training above 85% See: http://www.heart.org/HEARTORG/HealthyLiving/PhysicalActivity/FitnessBasics/Target-Heart-Rates_UCM_434341_Article.jsp#.V1mkN_krLIU


My goal: To get the time down to ~30 minutes so I can get home to my family quicker, and Maybe if my heart rate is lower I can improve faster (who knows). I love my bike, even though it is a basic model I have used it for close to 10 years now and I wanted to keep it as close to a bike as possible,
and to make it so that I could ride it without the motor (or if the motor broke or battery discharged) with the least impact on cycling performance without a motor.

All in all I think this set up has achieved these goals.

 

[The fingers]

Quite stealthy. 8)

 

[abecrizer]

My only problem is:
At the steepest part of my ride the motor makes a terrible grinding sound and stops putting out power.
I stop and power up again, it may happen again one time, but then goes away and does not return.
Motor performance is fine after and the motor spins freely. I can get a smilar noise if a apply power and do not let the bike move.
Should I deal with this by reducing power during this lower RPM state? (set PAS to 3 instead of 5?)

Over heating:
How do I know if I am over heating something?
On a hot day the motor and controller are warm, but I can hold my hand on both of them without having to remove for comfort.
What over heats first (motor or controller) and how can I check so it doesn't blow up?

Battery:
1) My battery lasted almost 3 rides. It seems I could get by with smaller, lighter battery.
Any advice about how to figure out an ideal watt hours?
2) Is it best to charge every time or let the battery go mostly dead in between charges.

Drop bar set up:
1) Best way do do brake sensors with drop bars? The only thing I have found is a "Hidden wire brake sensor".
This seems to be the only way, I will get some unless someone else has another solution.

The last thing is more of an idea:
Has any one made a e-bike motor controller that is driven by the riders heart rate instead of a throttle or pedal sensor?
Ie: Gives more power if if your HR is 85% of maximum than if it is a 50% of max.

In conclussion, thanks to the endless sphere community for all the help keeping me on the road.
I do not have the knowledge it would have taken to really execute this project without the help and guidance of community members.
Thanks.

 

[LewTwo]

...
What I did for now is just ghetto taped all that stuff onto the stem (please feel free to ridicule my lack of workmanship, I am a little embarrased about it).
...

Perhaps something like this could help with that problem:
https://www.amazon.com/dp/B014KT6WWQ
Bicycle Handle Bar Extender Mount

 

[Cephalotus]

Although ugly it does work. If you have to cut one of these rings...

Those five little magnets usually just fit inside the screw heads of the small chain ring. No plastic ring needed... (the polarity needs to be correct!)

 

[abecrizer]

Ok, so you mean, take them out of the plastic and press them into the chain ring screws. I like it. Do you have problems removing them to get the Screws out?

 

[ColinB]

Battery:
1) My battery lasted almost 3 rides. It seems I could get by with smaller, lighter battery.
Any advice about how to figure out an ideal watt hours?
2) Is it best to charge every time or let the battery go mostly dead in between charges.

1) It depends. You need to size a battery in two ways: 1) It has the capacity to take you the required distance without going flat. (Aim for a 80% discharge at the very most.) And 2) Is it rated to deliver the power you require? Larger packs are generally rated to be able to deliver more power.

2) Depends on your battery. Time to read up on the care and feeding of your battery, or it will not last for very long. If it is Lithium, I think they all dis-like full discharges. Don't do it! If not using your lithium battery for a while (maybe a week or more) leave it at 80% full, or there-abouts.

I bought a battery from Ping. I checked to see which batteries were rated for the power I wanted. I knew I'd want 5-800 watts ish, so settled on a 20Ah monster that is rated a bit higher. Heavy, yes. But I've had it for about 2 years and 14,000km. Still going! I could have bought a battery half the size, but I would have had to limit the power to my motor so I didn't overstress the battery. Looking back, that would have worked also. If I had bought a battery rated for just 300watts, I'm pretty sure I would have killed it by now, from running at maximum power constantly. Would have saved a bunch of weight though.

Colin