Following my first mid motor bike conversion I thought I would give some feedback, via a number of posts, which hopefully will be useful to those thinking of doing something similar.
Some general advice as follows:
1. If you have the slightest doubt about your DIY skills, don’t do it - pay someone else. Do not believe for a moment anyone who suggests that a mid motor conversion is straightforward.
2. If you are “time poor”, don’t do it - pay someone else. It took me 10 days straight (I am retired) and there are people with the necessary skills out there whose prices, with hindsight, seem incredibly reasonable.
3. If you have delicate aesthetic sensibilities, don’t do it. IMHO even with the best attention to detail the completed conversion will not look pretty after it ends up covered in cable ties, shrink wrap and electrical tape.
4. If you chose to ignore the above then be prepared to take a hacksaw/ angle grinder/ drill to the bike frame and/or the motor kit components. Rather alarming on a shiny new bike.
5. If you are converting a new bike, as a consequence of no. 4, be prepared to wave goodbye to your warranty. In my case the bike shop was totally upfront with me and said they would not even service an ebike conversion due to the liability they might incur for any subsequent component failure. In truth fitting any sort of ebike conversion kit is going to invalidate your warranty.
6. Be prepared to recycle all existing components attached directly or indirectly to the bottom bracket of the donor bike. A surprisingly large bag full as it turns out.
7. It appears to be popular to get the kits directly/ indirectly from China but I chose to pay over the odds to get both the motor kit and battery from a UK supplier (https://custombuilt-ebikes.co.uk) who A) actually had them in stock and B) I could (and did) discuss the build or any other issues with. I do not regret that decision.
8. If possible purchase the conversion kit and battery before the donor bike in order to check that the bike is suitable. If you are proposing to use a down tube battery having it to hand allows you to check both the space it requires and the usability of the bike’s bottle cage fixings for mounting it. Also check where you you can make additional fixings into the frame using rivet nuts taking into consideration the space you will need to operate the required tools.
9. Factor in the cost of purchasing or borrowing additional bike/ workshop tools if you are not well supplied with them. If you are new to the term rivet nut (or rivnut) you need to do some googling and get in some practice with the correct tools before you start drilling holes in your bike frame.
10. Would I do it again? Having got this far up the learning curve I hope to do it much faster next time and I have just purchased another kit (with rack mount battery) and a step though frame bike to do something similar for my partner. However, when the swearing starts, just remember I told you “don’t do it”.
Part 2 will cover donor bike selection.
Some general advice as follows:
1. If you have the slightest doubt about your DIY skills, don’t do it - pay someone else. Do not believe for a moment anyone who suggests that a mid motor conversion is straightforward.
2. If you are “time poor”, don’t do it - pay someone else. It took me 10 days straight (I am retired) and there are people with the necessary skills out there whose prices, with hindsight, seem incredibly reasonable.
3. If you have delicate aesthetic sensibilities, don’t do it. IMHO even with the best attention to detail the completed conversion will not look pretty after it ends up covered in cable ties, shrink wrap and electrical tape.
4. If you chose to ignore the above then be prepared to take a hacksaw/ angle grinder/ drill to the bike frame and/or the motor kit components. Rather alarming on a shiny new bike.
5. If you are converting a new bike, as a consequence of no. 4, be prepared to wave goodbye to your warranty. In my case the bike shop was totally upfront with me and said they would not even service an ebike conversion due to the liability they might incur for any subsequent component failure. In truth fitting any sort of ebike conversion kit is going to invalidate your warranty.
6. Be prepared to recycle all existing components attached directly or indirectly to the bottom bracket of the donor bike. A surprisingly large bag full as it turns out.
7. It appears to be popular to get the kits directly/ indirectly from China but I chose to pay over the odds to get both the motor kit and battery from a UK supplier (https://custombuilt-ebikes.co.uk) who A) actually had them in stock and B) I could (and did) discuss the build or any other issues with. I do not regret that decision.
8. If possible purchase the conversion kit and battery before the donor bike in order to check that the bike is suitable. If you are proposing to use a down tube battery having it to hand allows you to check both the space it requires and the usability of the bike’s bottle cage fixings for mounting it. Also check where you you can make additional fixings into the frame using rivet nuts taking into consideration the space you will need to operate the required tools.
9. Factor in the cost of purchasing or borrowing additional bike/ workshop tools if you are not well supplied with them. If you are new to the term rivet nut (or rivnut) you need to do some googling and get in some practice with the correct tools before you start drilling holes in your bike frame.
10. Would I do it again? Having got this far up the learning curve I hope to do it much faster next time and I have just purchased another kit (with rack mount battery) and a step though frame bike to do something similar for my partner. However, when the swearing starts, just remember I told you “don’t do it”.
Part 2 will cover donor bike selection.
