Elife La Grande 26" electric bike drive crank needs replacing

russell

Pedelecer
Oct 15, 2008
91
5
I have had my Elife for about 3 years now and its been excellent until today when my drive side pedal came away. On retrieving my pedal I attempted to screw it back into the crank but noticed the thread had disintegrated. I thought it would be a case of using a crank puller to take off the damaged crank but a new one and fix it but when I pulled the crank off the drive sprockets are part of the crank so I am going to have to replace but not sure where or what I should be looking for. Once I find the correct replacement I am confident enough to fix it . I called Halfords who were not very helpful and didnt seem to know what I was talking about. My bike I think is 18 gears, 3 different size sprockets on the crank and 6 varying size cogs on the back wheel. If someone could advise me I would be most grateful. I am 77 years of age so please be gentle. thanks
 

Raboa

Esteemed Pedelecer
Aug 12, 2014
511
174
50
Hi, it sounds like you have a square taper bottom bracket.
This crankset will fit a square taper crankset and has 3 chainrings. Gear Ratio: 48-38-28 teeth.


This crankset is a basic model from a good brand, You can get cranksets which are lighter and ones with replaceable chainrings but they are more expensive.

Hope this helps.
 

slowcoach

Pedelecer
Dec 11, 2020
136
89
If I understand you correctly, it is the thread in the crank for the pedal to screw into that has disintegrated.
If that is the case, then you should be able to replace this thread with a repair bushing.

 

russell

Pedelecer
Oct 15, 2008
91
5
Hi, it sounds like you have a square taper bottom bracket.
This crankset will fit a square taper crankset and has 3 chainrings. Gear Ratio: 48-38-28 teeth.


This crankset is a basic model from a good brand, You can get cranksets which are lighter and ones with replaceable chainrings but they are more expensive.

Hope this helps.
Thank you so much for the information. I have ordered the crank set you suggested also a new pair of pedals, the will be delivered on Wednesday. Fingers crossed I can manage to fit them.
 

AndyBike

Esteemed Pedelecer
Nov 8, 2020
465
210
Thank you so much for the information. I have ordered the crank set you suggested also a new pair of pedals, the will be delivered on Wednesday. Fingers crossed I can manage to fit them.
The pedals will either have an L or an R on them. Obviously this means one is designed for the left crank arm and the other for the well other crank arm.
So a bit of important grease on the pedal/crank threads and it should screw in easily. It should never be tight. So just make sure youre screwing int he correct pedal to the correct side and when it comes to the end tighten pretty tight. It's a 15mm spanner*.
You might find the bit you put the spanner on is quite narrow and a standard mechanics type spanner is too wide.
Welcome to the joys of needing to build up your own specific bike kits :D
Pedal spanners are quite inexpensive, longer handles are usually better than shorter handles, as it needs to be pretty tight.

Not sure how confident you feel about joining bike sites with the need to buy things from them but Wiggle is well known and their prices are usually very good. The spanner above isnt the best, but i think for your needs it will deffo be good enough. It's not like its going to be in daily use.
 

russell

Pedelecer
Oct 15, 2008
91
5
The pedals will either have an L or an R on them. Obviously this means one is designed for the left crank arm and the other for the well other crank arm.
So a bit of important grease on the pedal/crank threads and it should screw in easily. It should never be tight. So just make sure youre screwing int he correct pedal to the correct side and when it comes to the end tighten pretty tight. It's a 15mm spanner*.
You might find the bit you put the spanner on is quite narrow and a standard mechanics type spanner is too wide.
Welcome to the joys of needing to build up your own specific bike kits :D
Pedal spanners are quite inexpensive, longer handles are usually better than shorter handles, as it needs to be pretty tight.

Not sure how confident you feel about joining bike sites with the need to buy things from them but Wiggle is well known and their prices are usually very good. The spanner above isnt the best, but i think for your needs it will deffo be good enough. It's not like its going to be in daily use.
I received the new crank set which looks very good quality but it is slightly different from the damaged one. I have attached some pics. The new one has a raised rim on the inside face, other than that it looks fine, I'm just not confident if I should fit it or not . I hope I can as it looks so much better quality than the old one.... I would be grateful for your advise,, regards
 

Attachments

Raboa

Esteemed Pedelecer
Aug 12, 2014
511
174
50
Hi, put a flat piece of plastic / cardboard / wood against the lip then measure from the cardboard (inside) to the outside edge of the square hole in the crank (outside).
Measure from the edge of the bottom bracket (frame) to the outside of the bottom bracket spindle.
This should help you work out if there is enough clearance.
 

russell

Pedelecer
Oct 15, 2008
91
5
Hi, put a flat piece of plastic / cardboard / wood against the lip then measure from the cardboard (inside) to the outside edge of the square hole in the crank (outside).
Measure from the edge of the bottom bracket (frame) to the outside of the bottom bracket spindle.
This should help you work out if there is enough clearance.
Thank you for the guidance, I am a little confused regarding the bottom bracket but will try to see what I can do. I have slipped the new crank onto the square axle and it looks as if its not catching on anything but of course In have not fixed properly in case I need to send it back if I can..
 

Raboa

Esteemed Pedelecer
Aug 12, 2014
511
174
50
When you tighten the bolt that fits into the bottom bracket spindle thread it pushes the crank into the square taper.
You could put the crank on untightened and post a photograph of the space between the crank and frame.
Another thing you could do is put the old crank on untightened and measure the space between the crank and frame. Then tighten the old crank and again measure the space between the crank and frame. This will give a measurement of how much the crank pushes in once tightened.
You will then know if you have enough clearance for the new crank once tightened.
If you are still unsure take the bike and new crank to a bike shop and get their guidance, they will put it on for you for a small fee.
 

russell

Pedelecer
Oct 15, 2008
91
5
When you tighten the bolt that fits into the bottom bracket spindle thread it pushes the crank into the square taper.
You could put the crank on untightened and post a photograph of the space between the crank and frame.
Another thing you could do is put the old crank on untightened and measure the space between the crank and frame. Then tighten the old crank and again measure the space between the crank and frame. This will give a measurement of how much the crank pushes in once tightened.
You will then know if you have enough clearance for the new crank once tightened.
If you are still unsure take the bike and new crank to a bike shop and get their guidance, they will put it on for you for a small fee.
Hello again. I should have mentioned that there is a sensor disc which the crank gets close to when in place, that was what I was concerned about.

I slid the old crank on but never tightened it up to see how close it got to the sensor. Then I slid the new one and the space seems to be the same so maybe I could be lucky. there the raised lip on the new crank is about 5mm closer to the sensor than the old one. Tomorrow I am going to slip the new one on and tighten it up and see what happens. I do apologise for being a nuisance but I am desperate to get back on my bike 5 weeks ago my back tyre blew and I finished up falling off my bike. I broke 3 ribs which was very painful and then only thing you can do is take pain killers and rest. I am on the mend now but need to get my confidence back. I was at the time quite disappointed that although the road I was on is quite busy, not a single car stopped to see if I was ok. They might be morons out there but then after using this wonderful website and asking for help, everyone is so kind and helpful which has re-established my faith in human nature Thank you again
 

russell

Pedelecer
Oct 15, 2008
91
5
When you tighten the bolt that fits into the bottom bracket spindle thread it pushes the crank into the square taper.
You could put the crank on untightened and post a photograph of the space between the crank and frame.
Another thing you could do is put the old crank on untightened and measure the space between the crank and frame. Then tighten the old crank and again measure the space between the crank and frame. This will give a measurement of how much the crank pushes in once tightened.
You will then know if you have enough clearance for the new crank once tightened.
If you are still unsure take the bike and new crank to a bike shop and get their guidance, they will put it on for you for a small fee.
Hello again,, I am over the moon. I decided to try the new one for size and fit and bingo it fits fine, not touching anything. My new pedals arrived today and again decent quality. I sent 2 sets back to Amazon which were really poor quality. I am really grateful for your kindness and consideration. It is thanks to you for giving me the confidence to try. I will be going out on my bike tomorrow, not too far to start with as I'm wondering now what will be next.
 

sjpt

Esteemed Pedelecer
Jun 8, 2018
3,138
2,347
Enjoy, good luck with it.
 

Raboa

Esteemed Pedelecer
Aug 12, 2014
511
174
50
Hi, glad to hear that it fits ok, this forum has members who are more than willing to share their knowledge.
 

russell

Pedelecer
Oct 15, 2008
91
5
Hi, glad to hear that it fits ok, this forum has members who are more than willing to share their knowledge.
Hi, glad to hear that it fits ok, this forum has members who are more than willing to share their knowledge.
Hi, glad to hear that it fits ok, this forum has members who are more than willing to share their knowledge.

I think I may have celebrated a little early. Went out on my daily 10 mile this morning and something didnt feel right with my right pedal. I stopped and found the new crank set had come loose. I happened to have the right size allen key and tightened it back up but now I feel very nervous when I go out just thinking about whats going to happen next.

Should I tighten the bolt very tight maybe using a bar or is it possible to overtighten . Is there anything I can do to stop it coming loose again.... Thanks
 

russell

Pedelecer
Oct 15, 2008
91
5
Hi, it sounds like you have a square taper bottom bracket.
This crankset will fit a square taper crankset and has 3 chainrings. Gear Ratio: 48-38-28 teeth.


This crankset is a basic model from a good brand, You can get cranksets which are lighter and ones with replaceable chainrings but they are more expensive.

Hope this helps.
Hello again,, I wonder if you can give me the benefit of your knowledge and experience....I my last episode I fitted the new crank set and new pedals. I had difficulty in getting the chain on to the biggest chain ring, the guide would go over far enough to get the chain onto the chain ring. I adjusted the cable as much as I could and eventually got it on. I thought wonderful and went out for about 10 miles everything seemed fine and I reported back to you on the success. I was a bit off colour for a couple of weeks so didnt go out again. I then decide to venture out, on the way back The right pedal seemed strange, I stopped and found the new crank set bolt had come loose. I tightened it up as tight as I could and got although the crank seemed a little stiff. Before I went out again, I checked both pedals and crank sets for tightness and game another tightening. Now everything is very tight I can hardly turn the pedal. I have had a look on the internet as I didnt feel I could bother you but that was all about the bottom bracket which I found difficult to understand. I then rang a bike shop in Derby who asked if I had fitted a new bottom bracket and suggested that this could be the problem, which would account for me having difficulty in engaging top gear..I have looked for information on my bike Elife La Grande 26"| fold up bottom bracket but cant find anything and not sure what kind of bottom bracket I have I do understand some are pressed in some are screw in and I dare say if I have the screw in one I could replace that..I'm at a bit of a loss at the moment and feeling quite depressed.
 

Raboa

Esteemed Pedelecer
Aug 12, 2014
511
174
50
Your chain might be too short due to the amount of teeth on the biggest chainring causing tightness in the system. Take a photograph of your rear derailleur when you are feeling the tightness and post it on here.
It is not advisable to use your biggest chainring and biggest gear on your rear cassette, this can cause stress on your hearing system.
New chains are not that expensive so it might be worth buying a new one anyway.
Here is an example of one, other places are available.
 

russell

Pedelecer
Oct 15, 2008
91
5
Your chain might be too short due to the amount of teeth on the biggest chainring causing tightness in the system. Take a photograph of your rear derailleur when you are feeling the tightness and post it on here.
It is not advisable to use your biggest chainring and biggest gear on your rear cassette, this can cause stress on your hearing system.
New chains are not that expensive so it might be worth buying a new one anyway.
Here is an example of one, other places are available.
Sorry my friends I don't think I explained very well. The number of teeth on the new set (48) is the same as the old one so the chain should be ok. Even when I take the chain off the crank it is very stiff. I have loosened the crank bolt slightly and everything seems ok.
I very rarely change my chain set as I have no need to change gear on the route I take. I leave it on the biggest cog on the front and smallest on the back, set my electric to level 1 and everything operates ok
 

Raboa

Esteemed Pedelecer
Aug 12, 2014
511
174
50
I had a look for your bike and there is not much detail.
The only thing I can think of is that your chain line is affected.
It might be worth trying to add a couple of washers to the crank bolt and then fully tighten again.
Post some pictures of your bottom bracket and we might be able to tell you what type it is.
 

russell

Pedelecer
Oct 15, 2008
91
5
I had a look for your bike and there is not much detail.
The only thing I can think of is that your chain line is affected.
It might be worth trying to add a couple of washers to the crank bolt and then fully tighten again.
Post some pictures of your bottom bracket and we might be able to tell you what type it is.
Thank you for the reply. I am going away tomorrow fro 1 week and will try your suggestion with the washers, in the meantime I managed to get the correct battery carrier for my bike from Ebikes, they were very helpful and informed me that my bike is the Commute model if thats any help, I have tried to find more information without success maybe you know the secrets of finding the info, with there being so many variations its difficult. Kind regards, contact you when i get back.
 

russell

Pedelecer
Oct 15, 2008
91
5
Thank you for the reply. I am going away tomorrow fro 1 week and will try your suggestion with the washers, in the meantime I managed to get the correct battery carrier for my bike from Ebikes, they were very helpful and informed me that my bike is the Commute model if thats any help, I have tried to find more information without success maybe you know the secrets of finding the info, with there being so many variations its difficult. Kind regards, contact you when i get back.
As I mentioned before I had a week away on holiday but before I went I called into a new bike repair place in Derby. They were very helpful but quite busy. I left the bike with them for a week so they were under no pressure to get round to it. The chap rang me back within the hour and explained that crank set I had fitted was not perfect for the job due to the curved rim on the inside of the crank which I had mentioned in my previous post. He explained that when tightening the crank set up it was fouling on the sensor disk and that he would grind down the curved part of the set and refit it. I asked him to do whatever was required to get my bike fit for use. I was amazed when he rang me within an hour and explained that what he had done had cured the problem, he had also carried out a check on the rest of the bike and it was ready for collection.

When I collected the bike it rode better than it had ever done and I am elated. Thanks for the communications and guidance
 
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