Poke holes in my conversion idea!

[Lizzy]

So I am having some 75% serious thoughts about lashing out on a Solarbike rack conversion kit for my old hybrid – an old but well cared for Trek FX.

Reason being, I am struggling to stay motivated to commute on my road bike. My trip is 28km each way, at the moment I’m getting one return trip in a week on my road bike, in one day and home the next. I am so slow and it takes so long it’s a stretch to say I enjoy it. I’m thinking that adding an e-bike to the mix will help me get back into a routine of riding more often, will help me regain/improve fitness over a gentler curve, etc etc (yes I do intend to continue and increase riding the roadie).

In principle I would be prepared to fork out for a new e-bike but I’m leaning towards conversion for this list of reasons:

1 – Cheaper and will probably appear janky & less attractive to thieves, whilst still doing the job (hopefully);
2 – Massive limitations on storage space at home, a new e-bike would mean putting the old hybrid out to pasture altogether and I don’t wanna, I’m weirdly fond of it and there’s enough stuff in the world already
3 – Perhaps lighter than a factory built e-bike once all’s said and done, still rideable at a pinch if the battery were to crap out.
4 – Don’t care about powerfulsomeness or capacity for stupid speeds, just want to get there & back without knackering myself once or twice a week.

Floor is open for critical analysis!

[Calvin27]

Floor is open for critical analysis!

Battery capacity is going to be the biggest thing. I infrequently ride an ebike to work (21km) and prefer my road bike. You will need approximately 15Ah at 36V minimum which is about a $600 battery and even then depending on terrain and power assist level. I twould be cutting it close after prolonged use and I would probably advise a spare charger at work to top it up.

[eldavo]

Sounds well thought out.
My personal variation of kit using your hybrid, would be the small silver 200W geared front hub with downtube bottle mount removable battery 11Ah 36V, thumb throttle that would be more like a switch, rest on it for 25kph assistance, leave it off for cruise economy pedal only when above useful motor assistance, just add bursts. Pedelec is just a bit more wires and magnets, good for hands free cruising, but use the assist levels to control on/off.

Rear rack mount I'd avoid depending on your bike luggage priorities, front hub with down tube mount battery handles nicely, manual handling a bit easier when parked etc. That said if you check my IG bike posts, I've done about 5000km in the past few months with a 42km each way commute daily with rear rack battery. Reason for that choice (although I got the bike in 2014 generally unused until recently) was to allow a removable aero frame bag as higher priority for max luggage without the wind-drag.

I bought Solarbike Matt's fixi/singlespeed prototype in 2010 as my first ebike starting a new commute back then, 25km with a 9Ah battery, single speed. Front geared hub is clutched so no drag when motor off, you can augment your pedal only effort as you see fit.
The kits haven't progressed radically in 5 years, bigger and blacker options, mid drive kits, but the original is a formula that is simple and works, the local support and warranty on the Chinese kits becomes useful if there's any battery issue in 6 months.
Re: lashing out, there are cheaper equivalent kits from the likes of Dillinger east based, but Solarbike has local shop/service option in Freo and CBD.

Melody Wheels Adrian has posted lacing ebike motors jobs, checking with him who he builds the hub motor wheels for, as that would be some extra credit to Solarbike or whoever else he builds them for, since he demonstrates the nitty gritty details for building solid wheels. I also had wheel issues with the Chinese built hub wheels that I had on that old prototype. Again local support helps with this, but I'd prefer the Melody built wheel kit.

Your 28km trip with a 25kph motor assistance, you can rely on hour and a bit commute without having to thrash yourself. It's cheaper/easier/more reliable to have a 2nd charger at work charging, removing the battery for theft security anyway, leave the charger at work, they're cheap as chips compared to a bigger heavier battery you have ride/carry both ways.

Re: Calvin's battery note, agreed if you want to go flat out you need power to burn, but you can double your range by easing back a bit, for negligible time loss. e.g. I have an 11Ah battery in the 36V Bosch mid drive, ride 42km with 2/5 bars remaining on average, I charge at work. The distance motivates me to conserve assistance. Using assistance above average trip speed is wasted battery power, about 8min is the usual difference between backing off on a trip, and going flat out and using max battery (1hr 28min to 1hr 36min say).
Just leg fitness from daily riding took trip time from over 2 1/4hrs at start to 1.5hrs within a month, then consistency of times increased and variation in times decreased, while battery use decreased.

I'm clearly not a "roadie" though I do have one road bike (but even that's a minivelo). For reasons of rough paths and disc brakes, bigger tyres with more comfort and dirty path traction, heads-up visibility to shared path hazards and dog park, plus all winter riding etc. I never found road bike riding to be the preference for my routes. I've chosen 41.5km of shared path rather than 36km with road sections, with electric assistance it's similar times to a colleague/neighbour roadie who rides about 20km of shared path out of his 36km for same trip, similar trip times. Different strokes for different folks.

[Aushiker]

On the battery question when I ride my converted Giant Defy to work, my commute is 42 km each way. I have no problems getting to work or home again (often at full support due to the Fremantle Doctor) on one charge but I do charge my battery at work and of course overnight at home. My battery is a Samsung 36V 10S 6P 29E 16.5 Ah frame mount battery.

I wrote up the initial conversion of my Bachetta Giro 20 ATT. This kit was subsequently moved over to the 2009 Giant Defy. The conversion is pretty much the same except on an upright bike.

[Lizzy]

Sounds well thought out.

Thanks eldavo and everyone! Sounds like I'm not entirely off-base. Some good info to have a think through here. And yes, battery endurance is my prime consideration. Sounds doable given Aushiker's testimonial.

I'm clearly not a "roadie"

Teeheee, me neither, roadie in my head = short for road bike by the broadest possible definition

[Calvin27]

Sorry, I forgot to mention 14.5Ah @36v is with a MTB setup including front forks and knobbies (I use it for mostly weekend adventure riding) with slicks and a flat bar road configuration, it's likely to go a lot further than that.

[eldavo]

Also in another couple recent posts in the ebike sub-forum here, it was pointed out that Dillinger is not local for wheel build quality/support.
That reminds me Glow-worm bicycles were an east coast option that have been around a long time and do good gear, have participated in the BNA e-bike industry articles and one of the staff did the ride from Perth to Sydney with a couple other ebikes.

I'm about to test a lighter friction drive kit intended for fair weather riding (when is that going to arrive Perth ) for least assistance, minimal battery, most pedal-only, and should fit your bike, keep standard wheels etc. I've had a beta friction drive before and like it for pedal only 80%, the 20% option there if you want it. Probably not what you want as your primary ebike, but good enough to keep sweat-free for appointments with similar trip times. Battery range I can get double the capacity in half the weight to the standard battery with a LiPo pack that is bottle sized, so the 24V system is a bonus as well for minimalism.
https://go-e.bike/en/