Alien Gents Special II - Improvments and Modifications

[NRG]

I'm not one to leave things alone for long so I've been steadily improving/changing my Alien Gents Special II. In my original thread:

http://www.pedelecs.co.uk/forum/electric-bicycles/5183-alien-gents-special-ii-first-impressions.html

I noted some areas that I felt could be improved on.

So this thread is really just to note and show the things I've done. In the original thread the pedals came in for a bit of stick, rightly so IMHO, but I've still not found a suitable replacement! The search continues....below is a shot of three pedals, the ones on the left are fitted to my DIY Peugeot conversion and are really superb....the middles ones are the Alien's and the r/h ones some replacement ones that looked and felt great but where even smaller!

The search continues...

I had concerns over the brakes at first but they have proved themselves to be well up to the job, although, I think a better brake block compound might be on the shopping list at some point.

The bike comes fitted with 26 x 1.75 Kenda tyres and whilst these are probably fine I wanted something a bit better and went for a pair or Marathon Cross tyres with Kevlar puncture protection. These are not as knobbly as the Kenda's but they are lighter and the rolling resistance is a touch better. They've also proved themselves quite well in the snow and ice.

Also note the rim 'tape' used on the Alien wheels is a simple large rubber band! I really don't like this as the band moves about when fitting the tyre and its possible for a small part of a spoke hole to be showing / not covered. I intend to replace it with a good quality fabric type tape in the near future....

Next up are rattles....there are two sources of rattles...the front bell! And more seriously the battery. The battery is mounted in the rear rack and slides into place on a pair of runners or guides molded into the battery case. There is a anti-theft removal lock at the rear but it does nothing to stop the battery from moving about.... by a fair bit, so to fit this I squeezed the guide channels on the battery together using a hammer and flat punch at four locations, two at the rear near the lock and two are the front of the battery a few CM down from the plastic connector housing. This created four 'lands' that grip better and stop things from moving, I also greased the runners and the lock at the same time.

I left the bell alone!

 

[NRG]

My next modification is to the chainwheel, I wanted two things here a chainwheel guard and slightly taller gearing. I'd tried fitting a bash guard to the original chainwheel but gave up due to clearance problems and bolt length issues so when I saw this 'cost effective' Shimano 3 ring setup with guard I thought I'd give it a shot. The standard setup is a 44/34/24 chainset which I found to be OK but top gear was just a bit low for me making cadance a touch too frantic for comfort when going down slight hills or at top speed with throttle assistance...I'm hoping at 48/38/28 it will sort this out.

My latest mod is the most ambitious. What's been obvious in the recent snow and ice is the Pedelec is an absolute liability! The last thing you want is to rotate the pedals and have the bike erupt into life and catapult it's self forward with you desperately trying to hand on or dear life! So I need a way to disable the pedelec allowing me to pedal without assistance but without having to turn the electrics off and at the same time keep the throttle functioning...

So I purchased from Alien a second light switch and mounted it on the right hand side of the handle bars.

The wires from this I integrated into the original wiring loom that runs through the frame to the controller in the rear frame box. The idea was to use the new light switch to turn the pedelec off and thus save any more on-road-embarrising-moments. The sensor is fed with 4.79 volts from the controller and while this could be routed to the new switch and used to switch the supply I felt a neater solution was to simply shunt the sensor output to GND or 0v at via a resistor and use the new switch to simply cut the resistor in and out of circuit. A) I would not need to splice into the supply wire, B) the supply would not be routed all the way to the handle bars and C) the pedelec connector remains intact

I wired up my 'scope to the sensor output and managed to capture the output which is a very neat square wave. Sorry for the fuzzy picture as this was taken one handed while rotating the pedals with the other!

I found with a bit of experimentation a 27R resistor shunted just about all the signal, with a 100R resistor there was still a small signal present so I estimate a 47R would be an ideal value but as I did not have one the 27R will have to do for now. At 4.79v the resistor is dumping 177mA to GND, I'm not sure if the sensor or sensor circuit is built to flow this amount of current but a 47R would flow 102mA which would be better IMHO so I'll change it at some point.

 

[NRG]

Anyhow, I mounted the resistor at the pedelec sensor connector in the controller box, this was a bit tricky as the connectors are small and you do not want too much solder as it will lock the little spring connector up solid meaning you wont be able to plug it back together! So just a pin head size of solder is needed.... I cut the connector and stripped the wires from the new switch and attached them to the resistor and the pedelec connector....

Here's the resistor going in....

And here is the finished connector....

Does it work? Oh yes! Well at least on the stand....I've not been out on it yet but I don't think its going to cause any issues...

EDIT: Experimented with different resistors again and it seems you can use quite a large shunt resistor so I've now settled on 1K for just under 5mA draw, should be OK I think....

 

[Kalimbakey]

Great Post!

This is a great post NRG, I have enjoyed reading about your modifications so far even though I have not yet joined the Alien owners club. Perhaps the people at Alien will take on board your solution to the pedelec bypass switch as it seems a really useful feature.

 

[daniel.weck]

Nice one !

 

[jerrysimon]

Wow this is becoming like the German Pedelec forum

Some great work there, well done again.

Regards

Jerry

 

[NRG]

Thanks guys, in theory this same way to disable the pedelec can be applied to other bikes as I'm pretty sure the same type of sensor is used widely throughout the industry.

 

[Caph]

The battery is mounted in the rear rack and slides into place on a pair of runners or guides molded into the battery case. There is a anti-theft removal lock at the rear but it does nothing to stop the battery from moving about.... by a fair bit, so to fit this I squeezed the guide channels on the battery together using a hammer and flat punch at four locations, two at the rear near the lock and two are the front of the battery a few CM down from the plastic connector housing.

For anyone less adventurous, an alternative solution to the rattling battery is to slide a set of screwdriver bits (still in their rubber/plastic casing) between the top of the battery and the rack. They are not visible and fit just tightly enough to prevent any rattle whatsoever. You can usually buy them from any pound shop. I've had mine in there for several months now and to be honest I'd completely forgotten about it until I read this.

 

[Caph]

What's been obvious in the recent snow and ice is the Pedelec is an absolute liability! The last thing you want is to rotate the pedals and have the bike erupt into life and catapult it's self forward with you desperately trying to hand on or dear life!

NRG, this is exactly what I was talking about when I said the bike rode like a moped. It is too powerful on the pedelec resulting in a very powerful initial motor kick in and a very limited feeling of it being a bike. You turn the pedals but you can't really put in much effort because you're already doing over 15mph! The bike actually wheel spins in the wet if I try and pull away using the throttle.

I'm not saying it's a bad thing, it's just not what I want from an ebike. I'm sure some people would kill for that amount of power on their ebike though! I mean nearly 20mph along the flat on throttle only is some going. I just much prefer to have the motor only kick in up hills with the option of using the throttle if I want any assistance on the flat. Each to their own though.

 

[jerrysimon]

The Alienocean (Bafang) motor has a lot of power for sure and is probably excellent for really hilly areas.

Regards

Jerry

 

[Caph]

The Alienocean (Bafang) motor has a lot of power for sure and is probably excellent for really hilly areas.

It's definitely got the power! Although I prefer my Galileo, I use the Alienocean for shopping. Practicality and power win out when I need to fill 2 large panniers, that's for sure.

 

[NRG]

You have an Alien GSII? I'm wondering if Alien have changed the controller, on mine the amount of assistance is proportional to the crank speed. The motor starts with a sharp kick (no Hall Sensors) but after that the speed ramps progressively as cadence increases up to the 'legal limit' where the power tails off....

 

[Caph]

You have an Alien GSII?

No, it's a GS1. I didn't mean to give the impression that it starts at full throttle, it's just that it's very powerful in normal pedelec mode. A bit too powerful for my liking. A high/low switch would have been a good addition I think, especially with the freewheel being sorted in the GS2.

 

[NRG]

Managed to get some miles under the belt today and the Pedelec mod works a treat, I'm very happy. Also the slightly taller gearing of the new chainwheel set works well. Top is now just a bit longer dropping cadence down to a more relaxed rate but it also means I can now keep up on down hill gradients instead of freewheeling... plus with a bit of throttle assistance on the flat I can just about touch 20 mph....

 

[NRG]

I upgraded the front brake blocks at the weekend, I was suffering from a lot of squeeling that no amount of adjustment would seem to fix.

I fitted these Avid 20R blocks and not only has the squeeling stopped but they also stop a little better:

...and finally I've found a pedal that I'm happy with...they are only a touch larger than the standard items but they have the same profile both sides and the bearings are smoother...

MKS MT-Lite MTB pedals:

 

[Kalimbakey]

Bike cost V scope for modification

You must be close to completing the modifications now NRG, I guess the relatively competitive cost of the GSII gives more scope to do what you have done so far and is certainly one of the reasons I have decided to go down the GSII route.

 

[Ducat]

Can't go wrong with a GS II, I've had mine for nearly a week and love it to bits, pulls like a train, even uphill. Only problem so far(apart from the standard squeaky brakes) was a loose stand. According to my cycle computer max speed so far with minimal pedal assist has been 22.4 mph, which is kinda scary if your a 21 stone fifty year old who hasn't ridden a bike for 25 years!

For the price its an amazing piece of kit.

 

[NRG]

You must be close to completing the modifications now NRG, I guess the relatively competitive cost of the GSII gives more scope to do what you have done so far and is certainly one of the reasons I have decided to go down the GSII route.

Yes, and really these mods aren't 100% necessary, the bike works well as is...its just I like to tweak and refine...all part of the fun

 

[eddieo]

having trouble with noisy front brakes on our wisper...cleaned them as per Fleccs instruction and things where much improved. but after the lay up over Christmas squeaking like crazy again maybe new pads then.......

 

[flecc]

Those Avid 20R pads mentioned above are excellent and very reasonably priced Eddie, I use them myself.

Clean the rims first before using them though.
.