This is interesting ... because I have "fork plates" with a particular very basic shape (I was thinking about making it lighter and more sexy ...cutting bits away , drilling holes, etc ... ) I can use it to balance on a office stool:

[ATTACH]2843[/ATTACH]

Now.. if I add some telescopic legs I have a travelling bike stand which would be brilliant. when I had THAT puncture I had to lay the bike down on its side to do the repair ...

I don't know about telescopic legs, but look at this arrangement on a postman's bike that I saw on a recent visit to Germany.

http://i451.photobucket.com/albums/qq236/d8veh/General%20ebike/IMG_0057.jpg

http://i451.photobucket.com/albums/qq236/d8veh/General%20ebike/IMG_0058.jpg

interesting...be great to be able to trigger those stabilizers when there is a front wheel blow out! ... did they lift and fold do you know? or just lift? ... be good to see the bike in motion ...

same thing on the way home... very impressive performance and then at about 11 miles battery started to go ... does this mean I need to get a smaller chainring? 32T perhaps? 28T? .... can it be worked out? Can someone tell me the maths? ...

Alan I think you need to calculate your gear ratios taking into account the following:

 

what rpm would the tongxin normally be doing if it was a hub motor in a normal bike and you were going along at full speed (e.g.15mph)

 

What rpm (cadence) do you pedal at when cruising fast? 100?

 

say for example your fast cruising cadence was 100 rpm and the tonxgin's speed at 15mph on a normal bike was 200 rpm. therefore your stokemonkey drive would have to have half the number of teeth on the motor as you have on your lh crank e.g. 20 teeth on the motor and 40 teeth on the crank.

 

Hope this helps :-)

Alan I think you need to calculate your gear ratios taking into account the following:

 

what rpm would the tongxin normally be doing if it was a hub motor in a normal bike and you were going along at full speed (e.g.15mph)

 

What rpm (cadence) do you pedal at when cruising fast? 100?

 

say for example your fast cruising cadence was 100 rpm and the tonxgin's speed at 15mph on a normal bike was 200 rpm. therefore your stokemonkey drive would have to have half the number of teeth on the motor as you have on your lh crank e.g. 20 teeth on the motor and 40 teeth on the crank.

 

Hope this helps :-)

 

Thanks oigoi. Tongxin is rated to 175 rpm. I've learned recently that when the motor spins it generates voltage and when that voltage reaches the voltage being delivered by the battery the power is affectively cut. Now I know that 175 rpm is only a rating but I'm guessing it needs to be up there somewhere before it can generate 36 volts... what I need to do I think is to change the gearing again to allow the motor to spin more.... I can't remember how many teeth I have on the sprocket on the motor but I think its 15. I could just order smaller ones and try them until i get what I want ... although if someone was to say .. I need 8 teeth or whatever , then it would save me some money. - I don't mind the time as I really enjoy messing about with my config! ... Meanwhile, I got two batteries and I'm going to use them!

re: cadence - I'll think about that ...

Thanks for the maths .. I got 36T and 15T I'll see if I can re-arrange the formula! ... ok ,, so I currently got less than half ...

ok - done some maths ... I would say that currently my cadence is about 64 and my motor is rpm'ing at about 160. This would be the result of having gears in the ration of 15 to 36 i.e 2/5 ths or 0.4 which is what I got ...

Edited October 29, 201114 yr by kitchenman

Hi kitchenman

 

Changing the Gearing will only affect your top speed

 

 

Frank

Hi kitchenman

 

Changing the Gearing will only affect your top speed

 

 

Frank

Umm ... but ... I just changed the gearing from 48T / 15T to 36T / 15T and I'm able now to get up Beech Hill! ... Isn't this because the motor is now able to spin more and perform better? ... When set to 48T / 15T I almost didn't make it! ...

Hi Off course it will climb better but your top speed must be slower by lowering the gearing you get more tourk

Hi Off course it will climb better but your top speed must be slower by lowering the gearing you get more tourk

I was happy with my speed and torque on Friday but the battery didn't last ...

Hi kitchenman

 

40 mph no pedaling will EAT battery's like 10/15 minutes or less You will need at least 36 volt 20 AH to get anywhere if you slow down to 20MPH and put in some pedaling effort you will get more range

 

with our 48 volt 10 ah battery's if you ride throttle only at 30mph you will empty the battery in 30 minutes

 

BUT that's 15 miles

 

 

Frank

Edited October 29, 201114 yr by banbury frank

Hi kitchenman

 

40 mph no pedaling will EAT battery's like 10/15 minutes or less You will need at least 36 volt 20 AH to get anywhere if you slow down to 20MPH and put in some pedaling effort you will get more range

 

with our 48 volt 10 ah battery's if you ride throttle only at 30mph you will empty the battery in 30 minutes

BUT that's 15 miles

Frank

Frank, this is Cytronex "kit" that used to be on the Cannondale CX700. Battery is 36v 4ah. My mission is to use what I have and to see how it performs on my recumbent. I'm going to commute for another year on my recumbent and then compare the stats that I have. So far, so good. I think I just need to change the gearing slightly and then hopefully the battery will last like it used to.

This was supposed to be a short tour around my bike video but my preparation was poor and the result is worse! ... I know where I've gone wrong and the next video should be much better and shorter! ... One of the things I had hoped to cover was removing the motor. It really is very easy. step-1: dis-engage the chain, step-2 remove the power cable and finally step-3 lift the motor out of the "drop ins" ...

Frank, this is Cytronex "kit" that used to be on the Cannondale CX700. Battery is 36v 4ah. My mission is to use what I have and to see how it performs on my recumbent. I'm going to commute for another year on my recumbent and then compare the stats that I have. So far, so good. I think I just need to change the gearing slightly and then hopefully the battery will last like it used to.

 

Or... as I did this morning .... dont press the assist/boost button so much! .... Made it all the way this morning using high speed mode with a very respectable 14.6 mph average and this was in wet conditions .. lots of leaves and mud on the road ... Very happy! ....

What peaks are you now running and Gearing as such?

what is the rpm max of the Tongxin motor and the battery + controller setup?

What peaks are you now running and Gearing as such?

what is the rpm max of the Tongxin motor and the battery + controller setup?

Peaks? .. can you put that another way! ..

Gearing: is now 36T / 15T so about 1:2 ratio (on the rhs I have a 14 speed Rohloff - To get up my steepist hill I am able to use 5th gear and high speed mode)

Rated rpm is 175. Its the 180watt motor. Its the standard 36 volt system that Cytronex supplied. Battery is 36 volt 4ah.

At the moment I am having to use the assist button to stop the assistance as the motor doesn't seem to be getting to that point when it is supposed to generate 36volt and hence stop assisting! ... (which is great if I only want to do 11 miles! ) ...

THis is a SHORT tour around the bike (4 mins)

 

What 4ah battery (Cell type) are you using and with what controller rated / peak (max amp draw) amp?

 

I'm interested as it clearly works very well with the gearing and to be honest keeping the rpm's quite low you can change with your own gearing. The lower rpm would also mean less heat through the motor so again its a plus point.

 

Gearing a hub like this is a very good way of opening up exactly what you'd like for whatever terrain while still keeping a small motor and small effciency out of a light system.

 

Definetly would get the most from the power available.

What 4ah battery (Cell type) are you using and with what controller rated / peak (max amp draw) amp?

 

I'm interested as it clearly works very well with the gearing and to be honest keeping the rpm's quite low you can change with your own gearing. The lower rpm would also mean less heat through the motor so again its a plus point.

 

Gearing a hub like this is a very good way of opening up exactly what you'd like for whatever terrain while still keeping a small motor and small effciency out of a light system.

 

Definetly would get the most from the power available.

 

THe cells are NI-MH. The charger has this on it if its any help ... 60/50 hz 1.8/1.0A ... OUTPUT: 36VDC/2.5A ... re: the controller ... I think its got some gen on a label .. I'll pop down to the bike shed later and check ....

The fact you get 11 miles out of a 4amp36v NI-HM is really good if you ask me.

Thats 13watt per mile. Which on the face of it doesn't sound alot but your probably pulling a high C rate out the batteries and therefore the actual capacity usually drops the more you pull from a cell.

 

I'm glad you got it all up and working though and now its just monkeying about with it to get exactly what you would like.

 

At your current setup on a 10amp 36v battery you'd get at least 27miles.

The fact you get 11 miles out of a 4amp36v NI-HM is really good if you ask me.

Thats 13watt per mile. Which on the face of it doesn't sound alot but your probably pulling a high C rate out the batteries and therefore the actual capacity usually drops the more you pull from a cell.

 

I'm glad you got it all up and working though and now its just monkeying about with it to get exactly what you would like.

 

At your current setup on a 10amp 36v battery you'd get at least 27miles.

 

Thanks .. Yes. I think that Cytronex are generally considered as having done well with their solution ... which is why I am still excited about what they are going to do next! ... The back of the controller has a label but not all the values are visable:

 

Rated Power: 250 Watt

Operating Voltage: 36 V

Voltage Protection: not visable.

Regulating Current: not visable.

Control Motor Speed at:not visable.

Had another learning experience this morning ... I cant show you the photo as I forgot my phone this morning (still no checklist!) .. but one of my chainwheels failed. One of the red plastic sides sheared off! I was alerted because I noticed the sound of the chain tapping on the forks and I stopped after 7 miles (half way). I had been pushing it so I suspect my chainline was not quite right and the stress on the chainwheel caused it to fail. Unfortunately I was not carrying a spare which I will obviously start doing and attempted to configure a single chainwheel but this didn't work because I could not get the tension right and the chain jumped of the sprocket causing a lock out which brought me down again! ... fortunately I was only doing 5mph and no damage was done to man or machine. I then removed the chain and completed the ride to work using manual power which surprisingly I managed quite easily. I conquered the remaining two hills without too much trouble. The bike must have been close to 30 kg as I was carrying both my batteries! ...

Had another learning experience this morning ... I cant show you the photo as I forgot my phone this morning (still no checklist!) .. but one of my chainwheels failed. ...

Bad luck! I guess this is the burden you have to carry for being a pioneer. I hope you carry on so that we can all learn from your experiences.

Bad luck! I guess this is the burden you have to carry for being a pioneer. I hope you carry on so that we can all learn from your experiences.

 

Thanks. I really need to sort out the chainline. Come up with a proper method for checking if its right or not ...

Regarding the issue with the motor not generating 36volts. Its been suggested to me that as its not in a wheel it never will which I tend to think is probably true. Do you think?

This is the battery

 

My second ebike was an early S/H Cytronex, a great set up and I loved it. I found I got between 15-20 miles on one charge. These bikes are supposed to be pedalled a lot more though, which is probably why the battery lasts longer.

 

Although I am sure the batteries do last longer, the spec says the battery will only give you 250 charge cycles!

 

Regards

 

Jerry

Edited November 2, 201114 yr by jerrysimon

Yes. Thats the one Jerry. I'm getting to work (15.2 miles) in high speed mode with a bit of battery to spare.