Been doing quite a bit of looking at conversion kits, but I have a specific need. I could buy an electric bike but already have a couple that I would rather convert. (Tricked out Turner Flux f/s and a Haro Mary xc 29er)

 

Shade under 6ft ...17st ( although this decreases with my dieting and beer drink diet twice a year...lol)I have problem with both of my knees that means I can't put pressure on the pedals to much degree. usually fine on the flat as long as I keep the cadence below about 70rpm and miles below 30. (starting off can be tricky as well but i can manage with the right gear selected)

 

So in an ideal world I would like to trundle along the trails at about 14-19mph getting some decent exercise and when I hit a hill get some assistance. I like to go out for 2-3 hours 20-35 miles.

 

I was going to fit a mid drive kit but after a bit of reading I don't think this is right for me....I may be wrong! I have access to a good machine workshop so can " make things to fit" on the lathe/milling machine if needed.

 

Any advise much appreciated....

You need to read this first:

 

General Advice for Bike Choice When Doing a Conversion | Pedelecs - Electric Bike Community

 

If you want practical help, you'll need to post links to retail sites showing your bike(s) and/or photos of your proposed conversion bikes(s). Very few here - if any - are likely to know what a "Tricked out Turner Flux f/s and a Haro Mary xc 29er" are.

 

As a general rule, nearly all Factory built crank drive bikes are torque sensor - meaning you need to put effort into the pedals for assist which likely isn't for you. Many kit crank drives for conversions though are cadence sensor - like the Bafang BBS range - several here use those: Just turning the pedals even without pressure provides assist. The majority (but not all) hub-drive bikes (factory and kits) are the latter cadence sensor too.

 

Without posting pics/links, many here won't expend the effort necessary to understand what you've got to offer helpful advice. Just sayin'.

You need to read this first:

 

General Advice for Bike Choice When Doing a Conversion | Pedelecs - Electric Bike Community

 

If you want practical help, you'll need to post links to retail sites showing your bike(s) and/or photos of your proposed conversion bikes(s). Very few here - if any - are likely to know what a "Tricked out Turner Flux f/s and a Haro Mary xc 29er" are.

 

As a general rule, nearly all Factory built crank drive bikes are torque sensor - meaning you need to put effort into the pedals for assist which likely isn't for you. Many kit crank drives for conversions though are cadence sensor - like the Bafang BBS range - several here use those: Just turning the pedals even without pressure provides assist. The majority (but not all) hub-drive bikes (factory and kits) are the latter cadence sensor too.

 

Without posting pics/links, many here won't expend the effort necessary to understand what you've got to offer helpful advice. Just sayin'.

Hi , thanks for your quick reply.

 

The Haro is my choice to convert. Its a 29er steel hard tail....i'll try to get a link up

 

https://lh4.googleusercontent.com/-J-0CiudOLeY/UfwbUSDahjI/AAAAAAAABxc/gwpxsKuGrww/s1024/DSC_2278.JPG

 

I should be fine working out the conversion......but my problem is deciding what type.

 

I am a little worried that the mid drives will always be assisting, even on the flat which isn't really what I want.

 

I was looking at the rear hub kits on amazon but there are very few 29er wheels under £500, which is getting near to the mid drive prices and most are for screw ons not cassettes.

 

 

I could use a 26" or 27.5"....but it would look a little strange and the geometry wouldn't be great. I'm not sure if the 700c kits would fit ( need to measure the back drop outs) or how wide a knobbly tyre the rim would take....(although I used a cyclo x tyre most of the time for less rolling resistance on the trails)

I am a little worried that the mid drives will always be assisting, even on the flat which isn't really what I want.

The style of assist comes mainly from the sensors. Torque sensors typically provide a proportion of the work you are putting in, from maybe 50% on lowest setting (you do 2/3 of the work, it does 1/3) to 300% on highest (you do 1/4, it does 3/4), or even a bit more. Cadence sensors turn on once you are pedalling, giving more power for higher settings regardless of how hard or fast you are pedalling.

 

More often mid-drives have torque sensing and hub drives have cadence sensing, but that is not always the case.

 

You can turn either off completely; you will have extra weight from the electrics but there shouldn't be significant extra drag regardless of drive and sensor type.

 

29er and 700c are the same rim diameter; 29er is mainly a marketing term designed to confuse the public. However, 29ers will probably have a wider rim for bigger tyres; if you go for a 700c setup make sure the rim is wide enough for the tyres you want to use.

 

~~~

p.s. General opinion seems to be that rear hub is a little simpler and best for general commuting and simple riding, and crank drive for off-road of very steep hills. Crank drive will give you much more transmission wear.

I fitted a Bbs01b mid drive to my hybrid 29, it's great, suits me and it will do what you want. I have fine control over how much assistance I get, I chose 9 power levels instead of 3 or 5. Some of the bridleways round here have steep sections so I fitted a 44t front ring instead of the 46, a bit more bottom end poke.

Also has a throttle, great for setting off.

Most appreciated all.....

I was looking at the bb02.... Could that have a throttle fitted for setting off?

If you want a throttle, I'd say that a hub motor would be better. You get a much smoother action and you don't have to worry about which gear you're in. With a crank motor, if you throttle in bottom gear, it's really jerky and tend to wheelie. If you try and start up in a high gear, you can damage your drive train and/or motor. It'll work as long as you think about what you're doing, but with a hub motor, you don't have to think.

If you want a throttle, I'd say that a hub motor would be better. You get a much smoother action and you don't have to worry about which gear you're in. With a crank motor, if you throttle in bottom gear, it's really jerky and tend to wheelie. If you try and start up in a high gear, you can damage your drive train and/or motor. It'll work as long as you think about what you're doing, but with a hub motor, you don't have to think.

I wish mine pulled a wheelie!