e-Bike Kit Electric bicycle conversion kits and accessories

Kona Blast elationebike conversion

Chapter Three: Test fitting the motor mount

What's the brown leather belt for? Multiple choice test later in this entry.

Did my initial test fit of the motor mount and as expected the odd frame geometry is supplying more challenges.

A quick list of issues follows:

I. Down tube angle does not match angle of motor mount.

II. Supplied 2 inch round u clamp is not appropriate for this application.
A. Oval down tube is 2.25 x 1.25 inches = u bolt too short and too wide.
B. Round contact surfaces not a close enough match to distribute the clamping force allowing tube damage.

III. Starting a 3.5 " bolt in the kick stand sandwich is near impossible due to derailer/ fender clearance.

IV. The motor mount must be cut or mounted farther forward than designed for.
A. Forward mounting would be best as I may want to transfer the mount to a regular frame in the future.
1. Forward mounting also gives more leeway in alignment due to added chain length.
a. Added required chain length means the supplied drive chain will not fit, it's just too short.

V. The kick stand mounting slot on the bracket is off center to align with a stock frame kick stand mounting tab. I need a slot in the center of the bracket to match up with my Esge stand and allow it to clear the rear tire and not stick out so far as to interfere with the crank arm.

I am slowly working these issues and hunting down appropriate components from some interesting sources, especially a replacement for the u clamp.

The holidays and some domocile damage from that nasty wind storm that blew through the Pacific Northwest last night are reducing the amount of time I can dedicate to the project currently. So bear with me as I plod through this. Like I said I am shooting for a Spring completion including debug and upgrades.

As a side note I have been in contact with Allan and am happy to announce that he will be contributing to this blog as I progress. He will add some comments related to his thinking when designing this product and keep us informed of planned upgrades and needed improvements.

I'll continue to give my accounting of the installation on this odd ball frame and won't pull any punches delivering an honest accounting warts and all.

As for that brown belt, multiple choice question.

What did I buy it for?

1. I'll be using it to hang myself if this doesn't work out.
2. I've lost so much weight I needed a new one.
3. Leather would make a great frame protecting surface under any clamps and my bike is brown or better known by it's official Ford color name "Dirt".

Chapter Two : Bottom bracket swap and chainline woes

Well, all the components and tools arrived from Harris yesterday. Order was complete including the grade 25 bearings. It came well packaged and everything was as advertised. I'll be ordering from them again if my LBS doesn't have what I need.

The crank removal went smoothly thanks to getting the specialty tools. Specifically the Shimano lock ring socket and crank puller. Both were Park tools and appear to be of a quality level that will allow me a lifetime of part time use. I did run into a bit of a snag when trying to loosen the pedals. A stock 9/16" wrench is too thick to fit between the crank arm and the pedal. Lucky for me I had a thin old 19/32" wrench which barely fit but saved me having to spend another $16 or more for a specialty pedal wrench. If that had not worked I probably would have ground down a cheap 9/16" rather than spend that extra money.

Before removing the old crank and gear set I measured the distance from the outer lip of the BB housing to the inner chainring it was 5/16". I did this to keep the same spacing and help ease the derailer adjustment. The old ring set was a 42/32/22. The supplied ring set is 48/38/28 a huge difference . Should this gearing prove too tall for my hill climbing needs I will convert to an IPS stoker crank and lower gearing if Allan has not come up with that 11 tooth drive sprocket by then. Luckily my derailer is a mid range Shimano MTB so it will barely fit. The cheaper Shimano MTB will only fit a 42 max ring size. I did have to move it up the seatpost almost 1/2" just to get the crank/rings on the BB spindle. The conversion to bearing and cone from cartridge BB was uneventful and again quite quick as I purchased a pin wrench and a lock ring wrench.

After tightening down the drive side crank I measured and the spacing dimension, it was reduced to 3/16". I did a quick front derailer adjustment and have found two more things to address. First the derailer will not drop the chain to low gear even when adjustment is maxed in that direction and second which was no surprise, the chain is a good six links too short. So time to get some BB spacers and pick that 1/8" back up and also a new longer chain is in order.

I don't want to appear obsessed with BB issues but the chain line and proper shifting is critical given that is the drive mechanism for both me power and the E power on this ride. Had I chosen a hub motor all this would be a non issue.

There you have it. Some minor issues that are just time sinks, nothing to panic about but things that will stretch out the conversion time. Glad I'm shooting for a Spring completion including upgrades and de bugging.

Lesson learned, anything other than a go hub is likely to take longer than expected.

One other thing to keep in mind is that I have no real bike wrenching experience. Mechanically inclined with auto and old motorcycle experience am I. Hints and tips from experienced bicycle wrenchers are welcome.

Chapter one: Starting down the ebike trail, decision and kit purchase

After much agonizing over which type of conversion kit to use I purchased an elation ebike bottom bracket drive kit from Oz which has finally arrived in the US after a bit of a wait. My main concern is no US distributor yet so it's all long distance so to speak.

I decided to go this route for multiple reasons. Local terrain includes many steep hills, the finished product needed to be light enough for me to lift into a transit bus bike carrier, I have no access to a machine shop and zero experience with electric bikes. This kit seemed to offer all that I was looking for. Mostly I wanted the bottom bracket mount Unite motor, motor freewheel adapter and the freewheeling crank set. I also liked the light weight, quick release, easy to carry, complete with handle battery pack.

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