Richardab

Thats great to hear. Do you commute offroad right through the year. Thats one thing i havent managed as it just gets too muddy and to be frank riding in the woods in the dark on my own is too spooky! How do you find the hardtail, i was debating using a short travel full suspension bike as a base as i have this feeling on a hardtail i will need to stop pedalling and unweight the bike over bumpy bits which will make the motor stop and start. A full suss you can stay seated and pedal through, but i fitted a suspension seat post and it seemed to do a reasonable job on my test runs and my terrain isnt crazy bumpy. Definately agree with you, its still about pedalling, on my winter commuter ebike i pedal just as hard as i did when i did the shorter unassisted commute, but now i just go twice as far in the same time.

OK this is the second of a pair of bikes i planned to build using the same battery pack. I built the single speed carbon commute bike last summer and its been doing winter commuting duties since September 2018 covering 3350 miles on a 35mile round trip commute. The build was in this thread: https://www.pedelecs.co.uk/forum/threads/carbon-single-speed-commuter.31528/ The sister bike was planned to do summer commuting which i normally do offroad. The winter road commuter had a q100, but i had bought a q128c at the same time, for this build. The base bike is arguably far too nice for an ebike conversion, but i had initially thought that about the winter commuter, but i was glad i stuck to converting a nice bike, as i spend so much time on it, its nice to have good components, and its also great starting with a bike 4-5kg lighter than a cheap equivelant as i have to lug it up and down stairs at the train station for the second half of my commute. I was looking for a secondhand aluminium Cannondale 29er with a lefty fork but i stumbled over a Cannondale FSi carbon at not much more than the aluminium versions. I am a huge fan of lefty forks and light bikes. Conversion has not been too difficult, i really wanted room for a water bottle as i do actually pedal quite hard along with the motor, so spent time getting the 48v 10.4ahr battery mounted forward in the frame, its mounted to the downtube with an additional waterbottle fixing added, and then enclosed in a frame bag to give extra protection from ‘waggling’ and the elements and to tidy cables away. Q128c has 11spd cassette which all but hides the motor. Diy torque arm is made from a piece of stainless steel angle set up to push up on the bottom of the chainstay. Really not into all the jubilee clip torque arm kits available and would not be happy clamping to the carbon frame, my arm just pushes up in an area that is designed to take the disc brake forces. The same method was used on the winter commuters carbon frame and has had no issues. I built the wheels up myself, it was a bit of a challenge finding matching front and back rims that were available in both 36hole for the q128c and 32hole for the lefty hub. PAS is mounted on the drive side of the hollowtech crank, it did require some thought but in the end i found a magnetic disk that was solid so just drilled it out with a tight friction fit to the crank axle spacer. Sensor is a bit bodgy, i cut the bracket around to clamp under the cable guide fitted to the bottom of the bottom bracket. This could well fall off so might need a mark2 version at some point. Intention was to run an eggrider but i am having some issues setting it up so I am also running an LCD3 as well initially. It should look much smarter with just the eggrider. Been for a couple of test rides, part on road/part offroad. Speed seemed not much greater than the q100 in most PAS levels but i can feel quite a bit more in level 5, not sure if the watt settings are the same as my q100 for 1-4 and then 5 is max, thats what it feels like. Bike handling was really nice, could hardly notice the weight and more importantly the weight distribution while off road. Will be doing longer offroad commute next week, about 35miles round trip with approx 50% offroad. Will be interesting to see how battery fares as on road commute of similar distance makes it with about 70% usage. If all goes to plan i have option to extend coming home route by 5miles and do 90% offroad. I used to do this once a week on my regular mtb but it was quite time consuming so hoping to be able to do it most days on the emtb.

Just to follow up on this. I am having a few teething issues with the eggrider control cutting out, so i swapped the KT-LCD3 from my road ebike. Pedalling forward did nothing and pedalling backwards made it go forwards so i swapped the orientation of the sensor and its working fine on the LCD3. Interestingly swapping back to the eggrider is also now working correctly so i don’t know what was going on. Still having issues with the eggrider in other departments so will be running both controls till its sorted. Will post a general build thread abouth the bike later.

The mind boggles!

Ahh just googled king meter...that is the disk I used, but I didn't use the sensor that came with it because the connectors weren't right. Can this be corrected on the Kuntung controller using the LCD3

I am pretty sure the sensor is exactly the same as the one I have on the q100. But the magnetic disk is different model to fit round the holowtech crank. Is the magnetic disk the thing that is dual or single? Am I doing any harm at the moment?

Building my second ebike with a Q128c motor. My first Q100c when I pedal forward I go forward, pedal back does nothing, but the Q128c pedal forward goes forward AND pedal backward goes forward, is this normal for Q128 or have I done something wrong. They both have the same Kuntung controller and the same battery. the q100 has a KT-LCD3 control and the q128 has an eggrider. Certainly no settings in teh eggrider to change this, but I don't recall anything in the LCD3 either so I don't think its the control. The crank sensor has the arrows spinning in the right direction, although the actual sensor points the different way to my q100, but I think I tried it both ways round and it did the same. Any thoughts out there?

I hung the battery from the top of the bars. I used a pair of these either side of the stem facing downwards. https://www.amazon.co.uk/DSstyles-Adapter-Aluminium-Handlebar-Mountain/dp/B01HG4FB24/ref=asc_df_B01HG4FB24/?tag=googshopuk-21&linkCode=df0&hvadid=310164787656&hvpos=1o4&hvnetw=g&hvrand=16258548690820539320&hvpone=&hvptwo=&hvqmt=&hvdev=t&hvdvcmdl=&hvlocint=&hvlocphy=1006715&hvtargid=pla-348350537230&psc=1 The bag does have a few holes cut in it for the mounts and might leak a tiny bit in heavy rain but the battery is within its own enclosure anyway so the bag is more as a second defense and to tidy the wires and make it stealthy! The frame mount is a much easier way to do it and my 29er build has the battery inside a frame bag again to give some additional weather protection and tidy it all away. See pic, not finished yet though.

I think a rack battery would be even further out back but lower so maybe marginally better. Riding in the saddle wasnt really a problem but as you know with singlespeed you sometimes need to honk it out of the saddle and that was really odd feeling. It was also a nightmare to lift as it was so tail heavy. I would say with the SS ebike the gearing is critical, initially i was running 39/15 but i couldnt keep up with the motor and used the battery up quickly. Changed to 44/15 and its much much better, i am helping most of the time, but its hard to pull away till the motor gets going and some bigger hills are better if i honk a bit and keep my rpm and the motors in the best range, both requiring being out of the saddle. A frame mount would be the obvious solution (and thats what i am doing on my 29er conversion) but i wanted this commuter to be stealthy so the bar bag is a good compromise.

I did it to my single speed commuter. Heres the thread. https://www.pedelecs.co.uk/forum/threads/carbon-single-speed-commuter.31528/#post-445022 2800miles since September last year

I did this one earlier this year. Seems great, but I did fit torque arms and was careful with fitting it. http://www.pedelecs.co.uk/forum/threads/carbon-single-speed-commuter.31528/#post-444038

Ahh that makes sense the heavier bike gets to terminal velocity quicker. And seeing as not many of us ride at terminal velocity! The heavier bike will be quicker at any point up to it Everydays a schoolday, cheers

Isn’t it basic schoolboy physics. Feather and rock fall at same rate in a vacuum, implying their weight has nothing to do with how fast they fall in air, its all air resistance. So two identical bikes but different weight would get to the same max speed. If it was the lovely wisper roady it would be quicker as it is much more aero than most other bikes. I can definately see how the wolverine would sell, think of its 15mph assistance as a hill helper, the rest of the time you are riding a relatively light bike beyond the assistance level. Its not like its much heavier than a typical bike and its extra weight would only really be a penalty on hills when the assitance would be kicking in. Beautiful looking bike

I think they can hear it when you are going by at 20mph, just because we can't hear it because of the wind noise doesn't mean they can't. I just couldn't help thinking what I would have been thinking had I heard me whizz by with that racket! Tis true the bone conduction phones are not great if you are an audiophile, but I have found them perfectly adequate for music, and although not terribly loud, loud enough, any louder and I think they would distract me from hearing traffic etc (and at least only I am subjected to my poor music taste!)

I tried a waterbottle speaker once, by the time I had it loud enough to hear over the wind noise, it was embarrassingly loud when slowing down for a junction etc, I felt like some sort of chav with a booming car stereo. The quality was also awful at that level. I have since bought some Aftershokz Trekz headphones. They transmit the sound into your head through bone conduction leaving your ears free to hear whats around.

Simple really, if you use a throttle then yes, if you only have PAS then they are not really required. I use PAS only and don't have them

Interesting! I know I said redistribute the weight but I am amazed that 1/2" is enough. Who knows?, its a frequency thing, its maybe that you have moved the resonance just enough to a speed that you never/rarely reach.

Interesting so your phone can just live in your pocket. What mode switching is that, I only have PAS levels on my KT-LCD3...i think

Oooo, I just googled the Eggrider, that looks interesting, do you have any experience with it. I really hate the KT-LCD controller on my bars as i already have a Garmin GPS telling me speed and distance and much more, although I wouldnt want my phone on the bars either. Do you know how this thing works, do you need the phone or is that just for advanced settings.

My recent build is now at a bit under 15kg. Base bike was 8.6kg, 11.6ah 48v battery inc controller about 3.5kg and q100c rear hub motor about 2.2kg, 0.5kg for LCD, wires and bag. It averages 19-20mph and I did 34 miles using 60% of the battery although I am pedalling a fair bit. http://www.pedelecs.co.uk/forum/threads/carbon-single-speed-commuter.31528/ I am sure you can build lighter if you reduce range or speed aspirations. I believe there is a Q85 motor also which I assume is lighter.

Any bike can have a speed wobble, its a natural resonance frequency, more often than not the speed it occurs is faster than normal speeds so rarely felt, but can be thown off by different weight or weight balance. I have a very light bike that does it at high speed, but its rare as i would not often be riding no handed at those speeds. On a heavier bike my bar bag can also induce it. If it does happen try holding your leg/thigh/knee against the top tube, it dampens the ‘harmonic motion’. I’m not sure there is a fix unless you redistribute the weight.

Mark 2 version competed. I have the battery bolted, upside, to the underside of the handlebar, then a bikepacking drybag is sleeved over the lot, wires run up from the BB inside the downtube and out one of the derailleur cable ports and straight into the bag. For the moment I have mounted the LCD on the bars, its ugly and not very stealthy, but its useful for a bit to get a better understanding of wattage and voltage use, I am already getting a feel for what PAS 1,2 and 3 feel like so don't need the LCD so I will put it inside the bag soon. The thumb control is super neat just under the brake lever, much nicer than reaching round onto the old saddlebag. The major change is the weight...it 'feels' several kilos lighter. The bag is around 1kg lighter than the previous saddlebag but I think its mostly down to balance, I can pick the bike up by the top tube in a normal manner and it just feels like a normal heavy bike rather than this unwieldy beast with all the weight at the back. Handling wise, the steering is heavier, but I have run bar bags before and the feel is the same. It does mean I can get out of the saddle without the bike going all over the place now.. There is a zipped pouch on the front of the bag which is just big enough for my tools and pump and work stuff. Any more than that and I will clip the now redundant saddlebag back on, but I tend to travel light. With the single speed gearing sorted and riding on PAS1, with occasional 2 and 3 for hills I am doing my 32mile round trip at 19-20mph average speed using 60% of the battery. Most importantly the overall door to door time is less than it was with the previous 16 mile round trip plus longer train journey and I feel about the same level of workout. The Q128c emtb is now underway.

Wheelbuilding is made out to be a bit of a black art. There is certainly some skill and more importantly patience required, but its not impossible to do DIY. I've done a dozen or so wheels in the last few years basically just using the internet as a guide, there is an excellent guide on Sheldonbrown.com, but you need to follow it to the letter or you will make mistakes and there is also several spoke length calculators available. Tensioning can be done by ear to get equalized, there are even apps that listen to plucking noise and tell you the tension, in the end I bought a tension meter. I'd forget cutting down old spokes, by the time you have found someone to do this and redo the threads you are probably in for more than new spokes. But in reality most people would sensibly just pay a shop to build a wheel, its not that expensive and you know it will be done right.

Been commuting on this bike a bit (I tend to ride offroad commute during the summer) so I can test it out and shake out the bugs before full time duties this autumn/winter. My average speed has massively increased, It was around 15mph peddling, now I average 20mph, with cruising speed around 22-23mph. Battery life has been disappointing at first, I think this is due to the top speed in the low 20's and my gearing on the singlespeed being more suitable for 18mph so I felt like I was spinning out and barely able to help the motor at the top end which meant I was probably using alot of battery juice whilst spinning my legs frantically. I have just changed the front chainring for a bigger one and this morning it was so much better at 90-100rpm and 22mph. It did make hills considerably harder so I was more reliant on the motor. Overall it looks like it should make a saving on the battery as I was in PAS1 most of the time. I suspect that proper gears would actually help more, but I am reluctant at the moment to fit them, but it is a fall back if I need to make the most efficient use of the battery. I am not happy with the weight balance all being at the back, it makes the bike unwieldy to carry when I get to the train station and although I cannot feel it when riding, if I stand up on the pedals its really noticeable and with the bigger gearing I feel the need to stand up on hills. So I am developing a Mk2 version of the bike with the battery mounted forwards, It should be just as stealthy and hopefully better balanced.

First test ride today. Wow, ok, lots of punch from pas3 and above, even 2 had enough to wizz along at 20mph with me only helping a little. Hill climbing was very impressive, my nemisis hill just down the road from me, which kills me every day on the singlespeed grinding up it at 5-6mph by the top was 15mph in pas 2 with me helping a fair bit or 18-20mph in pas 5 without much help from me. All seems to have held together ok, i am understandably going to keep my eye on the torque arms and drop outs, but it looks ok. The weight is obviously drastically increased, the bike weighed 8.6kg originally and the empty saddlebag i was using before added over 1kg. Its at 16kg now and is all at the back so noticable when picked up, but not really while riding. Questions: Is there any lubing i need to do to the q100, now or at intervals? This bike gets used for regular commuting 5 days a week rain or shine and i will be doubling its mileage to 32miles a day. Are there any specific settings i need to change in the lcd3, i found the p1 setting and changed to 202 as instructed somewhere on this forum, any others i can tweak that make things better. I think i might need a bigger chainring on the singlespeed though, i was spinning out over 22-23mph and i could still feel the motor engaged at that point but was barely able to help it out. Right now on to build two, i bought 2 motors a q100 and a q128 because i wasnt sure which to use and the motor was the cheap bit of the package so my plan is to build a hardtail 29er with the q128c and use the same battery. I don’t think it will be able to be quite as stealthy as this build, but i will try. I will put a build thread up when i get the plan formulated.