Specialised Stuntjumper bbs02 build.

[Rudolf Roskopp]

Hi everyone. My bafang kit arrived yesterday, so I’ve been putting it all together I’m still waiting for the battery, and the new 40t bling ring. I think the case I bought might be a bit to small for the battery, so if anyone have any suggestions, that would be welcome, my battery is 185mm x 90mm x 85mm.

I would like to change the chain and cassette it’s currently 9 speed , I was Thinking of getting the KMC X9 chain as they sell for £20 compared with £40 for the E9, has anyone used both who could advise if it worth getting the e9 or not?



My bike has a 73mm wide bottom bracket, so had to use spacers on the bracket, also there is not enough thread to get the end cap on. I’ll use thread lock and hopefully it won’t move around.

 

[Gavin]

so if anyone have any suggestions, that would be welcome, my battery is 185mm x 90mm x 85mm.

I've seen some people fit the battery to the underside of the downtube on full-sus conversions. You need to be careful of the following, obviously:

a) Ensure that the front wheel won't hit it on full front fork compression.
b) Find a foolproof way of keeping water/ mud spray off it.
c) Bolt it on securely and use a "belt and braces" approach!

Can't help you with the other bits

P.S- That's shaping up to be a seriously cool conversion- keep us posted with some piccies...

 

[Rudolf Roskopp]

Hi gavin thanks for the reply. Ive chosen the battery because it fits in the frame tube, the smallest hailong type battery was a bit to big to fit. I’m sure there’s a better solution. I don't like the idea unless it was in a hard case. I can imagine a scenario where a stone hits and damages the battery, a few hours later it’s smouldering away in the garage.

 

[soundwave]

put it in a back pack

 

[peter.c]

This works but you need an anti turn bracket the kmc 9 works well

 

[Rudolf Roskopp]

Did you make that bracket?

 

[peter.c]

Yes now make my own brackets out of stainless steel or aluminium chequer plate, 32 mm-35 mm hole saw and angle grind to shape take about an hour and a few drops of sweat and blood

 

[Fat Rat]

Hi welcome

 

[Rudolf Roskopp]

Thanks Peter, I’ll probably go that route in the end. What do you use in the frame to hold the bolts?

 

[peter.c]

Two rivnuts or if you do not want to drill a jubilee clip

 

[Rudolf Roskopp]

Version 1.0, rough as, but seems to do the job. Knee support thingy to hold the battery.

 

[peter.c]

Thats not going to move or come loose how to fix the battery bag is your next task

 

[Rudolf Roskopp]

Done about 50 miles on it now. I’ve changed the settings to Karl’s special sauce and the pas is way more smoother, plus I can now use throttle with pas turned off.

 

[peter.c]

Please can you give details of the battery pack without the bag size etc
thanks peter

 

[Rudolf Roskopp]

Battery description.



48 Volt Lithium E-Bike battery 11AH
LG M29 Cells
1700 watt continuous

This pack has been assembled using 52 LG M29 cells and 100% pure nickel strips for the welding

This pack has a 35 amp BMS on board

I have used the LG M29 cell as its well known for their excellent cycle life
I have put 11Ah in the description but its more like 11.6Ah

Pack approximate size

285mm length
95mm Width
80mm Height


It is a 13s4p

 

[peter.c]

Thanks for that

 

[RobN]

View attachment 36863

Done about 50 miles on it now. I’ve changed the settings to Karl’s special sauce and the pas is way more smoother, plus I can now use throttle with pas turned off.

Looks great that, nice job. Does the bling ring push the chain further inboard , ie more than the standard chainring supplied?
Regards
Rob.

 

[Rudolf Roskopp]

I believe it does, but couldn’t say for sure because I never tried the stock one.

 

[RobN]

OK no probs.Ta

 

[peter.c]

Yes the bling ring moves the line in, but only on 42 teeth and above the 36 is flat