Jonathan's 44 lbs Specialized FSR S-Works

[Jonathan]

I've been riding this several times to work and around town.
At 33V / 9.2Ah mode, I get ~ 15 miles till CA's LVC kicks in at 29V. It's about 8Ah drain.
At 66V / 4.6Ah mode, with 4 Ah drain the LVC cutsout @ 58V and I get about 9 miles.
Average voltage for these cells are like 2.9 - 3.1V /cell with a 20-35A load.

I think I need an extension pack to get me up to the Cherry Flat Reservoir and back. I'll currently looking into options of mounting it at the top of the top tube and seat post, or at the rear of the seat post. The pack size is going to be ~ 280x70x120 mm (11" x 2.75" x 4.75").

What do you guys think? What's the best location and method for stealth?
Keep in mind this ext pack is only mounted when more range is required.

Thanks,
Jonathan

pwbset: I like that paint job.
AussieJester: I messed up the negative mold of the CF/Kevlar enclosure, during the test build. I'll be revisiting this for the 66V / 4.6 Ah extension pack. Hopefully I'll have better luck the 2nd time around.
deecanio: It was Maytag's GT that inspired me to put the battery in the triangle.

 

[deecanio]

Hi Jonathan,

you did a great job with your pack so i would say do the same again right about here?.........................

 

[AussieJester]

I messed up the negative mold of the CF/Kevlar enclosure, during the test build. I'll be revisiting this for the 66V / 4.6 Ah extension pack. Hopefully I'll have better luck the 2nd time around.

Ahhh kk... I have made a few plugs/moulds myself not so long ago, I used floral foam (i forget the technical name for it)

Its really easy to cut and sand, when you have the shape you cover it with bondo/spray putty and rub it back to a shiny finish, then use it to make the mould for your project. Might be worth a shot if your method isnt working so well?I bought he foam from local florist 10 bricks for 50 cents each stuck them together with an adhesive glue and started shaping

Hope this helps

Kim

 

[Ben]

My mum calls it Oasis.

It's really easy (and fun) to shape.

 

[andys]

what did you end up doing for the freewheel? It stinks that they discontinued the 11-28 and 11-34 hyperglides. Doug is trying to get them back in production. I heard the bionx 9 speed freewheel wasn't very good at all.

How fast does the bike go at the lower voltage? I was told to be careful on climbing the hills with high amps with the geared hubs. Someone just tore up the nylon gears pretty good using the Phoenix 48 volt 40 amp controller and the BMC hubs when he nailed it from a standstill up a hill.

I am doing a light weight stealth build myself, using A Trek 950 Single track with a old Manitou TI fork, the BMC hub, a Nitro pro gas seatpost shock, and a 6 pound 38 volt 10.5AH LIPO pack from ebike.ca that fits in a great looking frame bag. I have posted a photo of the frame bag (comes with key switch and wiring) I was told two 36V 10AH batteries can be stuffed in there for you 72 volt speed demons. My build will be similar to the other photo. Stealthy!View attachment 1

 

[shinyballs]

I'll go with something like this to cover the batts in the frame. Easy and simple. You can use neoprene - used in wet suits, laptop sleeves, and just use velcro to open/close. Good protection against the elements.

Bike is by Bob Mcree

 

[docnjoj]

Neoprene! I shoulda thought of that! Tis is a neet bike, Jonathan. Also, that USPD on Bobs bike is quite elegant too, compared withr the current Ezip! Good luck with your new ride!
otherDoc

 

[pwbset]

Yeah, that's awesome! I'm so stupid I was trying things like denim! :lol:

 

[MitchJi]

I've been riding this several times to work and around town.
At 33V / 9.2Ah mode, I get ~ 15 miles till CA's LVC kicks in at 29V. It's about 8Ah drain.
At 66V / 4.6Ah mode, with 4 Ah drain the LVC cutsout @ 58V and I get about 9 miles.
Average voltage for these cells are like 2.9 - 3.1V /cell with a 20-35A load.

I think I need an extension pack to get me up to the Cherry Flat Reservoir and back. I'll currently looking into options of mounting it at the top of the top tube and seat post, or at the rear of the seat post. The pack size is going to be ~ 280x70x120 mm (11" x 2.75" x 4.75").

What do you guys think? What's the best location and method for stealth?
Keep in mind this ext pack is only mounted when more range is required.

Thanks,
Jonathan

Hi Jonathan,

Nice bike!

Can you add the additional cells to the side of the existing pack (would this make it too wide)? If so it I think this would be your stealthiest option (1 pack) and also best for handling (lower CG).

I think you might consider increasing the capacity of the original pack rather than having a second pack for occasional use. This should increase the life of the pack because you will be using the cells at a lower C rating and under normal use not discharging them as much.

Would you mind posting a brief comparison of your impressions of 33 v vs 66 v performance (acceleration, hill climbing and top speed)?

Why does range decrease at 66 V?

Thanks!

Mitch

 

[Jonathan]

Thanks guys for the input.

Over the weekend I slap together a prototype 2S1P (66V 2.3Ah) pack to the rear of the controller.
The two batteries were side by side making it look fat (not to be confused with PHAT!).
Me & jondoh took it on a pleasant +25 miles drive. Everything held up great.
However two additional pack was not enough, I still more than I wanted.

I will probably change the rear configuration to stack like a "T" and clam shell mount it to the controller's mounting bracket.

In the front I also plan to mount an "L" shape 2S1P pack. With both ext pack will bring up my capacity to 66V 9.2Ah (8Ah effective).

andys: I passed on the Bionx freewheel due to bad reviews and compatibility problems.

At 33V the top speed is 27 mph, while 66V it's 37 mph on flat. I typically pedal first to get 5-10 mph at red light before I floor it to pass cars, so it shouldn't be a problem on the gears. Nylon gears are pretty good. I've seen them failed on MiniMill but it's typically due to the operator.

I thought the Trek 950 is a road bike? Your's look like a MTBR. <confused!>

shinyballs: Where do you get large neoprene sheet like what Bob used?

MitchJi: If I increase the cell width anymore my knee would rub when I pedal. YES, I pedal, I use the motor to only 50% of the time. Although I would love to lower my CG as much as I can get away with.

The extension pack is only for occasional use where I need the range of +20 miles. With the stock pack I have plenty of speed and range for my 12 mile (one way) commute. That's the main reason why I need to design it so it can be install & removed in less than 10 minutes.

The reason I get decreased range @ 66V is due to the increase in average speed (+4 mph).
I'll try to conduct a more scientific experiment with regards to speed/climb/range when I have some more time.
I have to conduct an

 

[shinyballs]

Neoprene sheets are available at mcmaster or just google it..

 

[MitchJi]

I think I need an extension pack to get me up to the Cherry Flat Reservoir and back. I'll currently looking into options of mounting it at the top of the top tube and seat post, or at the rear of the seat post. The pack size is going to be ~ 280x70x120 mm (11" x 2.75" x 4.75").

What do you guys think? What's the best location and method for stealth?
Keep in mind this ext pack is only mounted when more range is required.

Thanks guys for the input.
However two additional pack was not enough, I still more than I wanted.

I will probably change the rear configuration to stack like a "T" and clam shell mount it to the controller's mounting bracket.

In the front I also plan to mount an "L" shape 2S1P pack. With both ext pack will bring up my capacity to 66V 9.2Ah (8Ah effective).


MitchJi: If I increase the cell width anymore my knee would rub when I pedal. YES, I pedal, I use the motor to only 50% of the time. Although I would love to lower my CG as much as I can get away with.

The extension pack is only for occasional use where I need the range of +20 miles. With the stock pack I have plenty of speed and range for my 12 mile (one way) commute. That's the main reason why I need to design it so it can be install & removed in less than 10 minutes.

I'll try to conduct a more scientific experiment with regards to speed/climb/range when I have some more time.
I have to conduct an

Hi Jonathan,

No hurry and it doesn't need to be scientific (overall impressions would be more than sufficient) but I would appreciate a little more information on the 33v vs 66v speed/acceleration/climb and range when you have it.

For battery mounting you might want to consider something like this:
http://endless-sphere.com/forums/viewtopic.php?f=14&t=4540&p=67222&hilit=+weight#p67222

Doctorbass's BATTERY RACK help stability!

I finally finished my alluminium battery rack for my 2kWh packs and i tryed it with 1kWh yesterday..

I would say that i'm pretty impress with the results!

The center of gravity is the lowest i acheived from now on the bike and the driving staility is awsome!

I have 55% weight on rear and 45% front without me on the bike!

the room to accept battery is more than enough

It doesn't squeeze or obstruct me when pedaling. the room for my leg have not changed.

Another option for occasional use might be one or two Panniers. If they were a little deep and the batteries were low the CG would be better than the seat post or top of the frame.

 

[cee]

hello Jonathan what year is your specialized s-works? and model its a nice bike thanks

 

[ktronik]

FYI, 7spd spacing is the same as 8spd spacing, so you could use up to a alivo shifter or old skool 8spd XT or XTR (on 7 or 8 spd sprockets)

Shimano made the freehub body bigger for 8spd (left spacing the same) , (from 7spd) but left the freehub body the same for 9spd, so only 9spd has smaller spacing.
This is reflected in the screw on sprockets so its all interchangeable.

Love the bike great work!

Ktronik

 

[swade]

How do you know if a freewheel is compatible with the BMC/Puma motor? Are they all based on a standard inner diameter (the part that screws on to the motor)?

This one looks great as it has 11t as its smallest cog:
http://www.bonthronebikes.co.uk/322-6652

 

[bumper]

what did you end up doing for the freewheel? It stinks that they discontinued the 11-28 and 11-34 hyperglides. Doug is trying to get them back in production. I heard the bionx 9 speed freewheel wasn't very good at all.

How fast does the bike go at the lower voltage? I was told to be careful on climbing the hills with high amps with the geared hubs. Someone just tore up the nylon gears pretty good using the Phoenix 48 volt 40 amp controller and the BMC hubs when he nailed it from a standstill up a hill.

I am doing a light weight stealth build myself, using A Trek 950 Single track with a old Manitou TI fork, the BMC hub, a Nitro pro gas seatpost shock, and a 6 pound 38 volt 10.5AH LIPO pack from ebike.ca that fits in a great looking frame bag. I have posted a photo of the frame bag (comes with key switch and wiring) I was told two 36V 10AH batteries can be stuffed in there for you 72 volt speed demons. My build will be similar to the other photo. Stealthy!View attachment 1

andys,
Re. the 2nd photo. Is it a problem that the bag interfere with the cables running to the rear brake and derailleur in the top tube? I'm considering a frame bag like that, but wanted to know if you had tried this. the cables on my top tube are exposed, run on the top and the bag would be hanging from this area. Thanks.

 

[Jonathan]

cee: It's a Specialized FSR S-Works build in 1999. I bought it from the original owner (with receipt of his store purchase) for a $400. It had a loose bottom bracket, which was a 5 minute job to fix. I'm now in a hunt for another FSR with disc since above 30mph can easily break down your cantilever brakes.

swade: They are standard ID. Mine came with a 7-speed freewheel, I was told that you can change to 8-speed, but never bother. After having my rig up for a while, I find that you only use the last two gear most of the time due to the high torque that it have. When I was testing my 408, I practically had to use the complete 2nd half of the set to do the Calaveras climb.

 

[andys]

"Re. the 2nd photo. Is it a problem that the bag interfere with the cables running to the rear brake and derailleur in the top tube? I'm considering a frame bag like that, but wanted to know if you had tried this. the cables on my top tube are exposed, run on the top and the bag would be hanging from this area. Thank"

It did interfere with the cables, as my bike has them open on top just like the one you described. it was an easy fix though. I just picked up some outer cable, and cut it to fit snug in between the area where the exposed cables ran. I then ran those cables inside the outer cable shell, and now they are unaffected by the straps.

The bag works great by the way. it is not too big or too small. i had enough room to feed all my wire connections into it and they are all out of sight and protected by the padded bag. I'll try to post some photos soon.

 

[cee]

hello Jonathan thanks for the reply havent been on lately that is really a nice looking bike i bought a specialized hardtail sport in march its a nice bike if i would of known about those fsr type i would of gotten one maybe next time thanks again for info.

 

[Jonathan]

A few member asked me about the charging solution of my pack so here goes.

I normally use a Mastech HY5020 for quick charging. This PS set to 36.5V can provide a quick 20A CC/CV charge (2.5C for my 4P configuration).
However, this is not the charger I would recommend for everyone. If you want to charge with power supply get the HY5005 it's a dual channel charger that capable of charging in series up to 100V / 5A. Remember to at least install a diode on the (+) output because these are very prone to rev bias.

You can do quick charge for about 5-10x then you'll start noticing that the power capacity of your pack have drop ~10%. Well it's because series charging will cause cell unbalance over time.

I then use a FMA CellPro 10S to balance. It will take anywhere from 30-120m to charge/balance my pack. This is a great charger for Lithium Ion (only) chemistry. The cool thing about it is they calculate the internal resistance of each cell in the pack, which is a great plus.

I've also make couple upgrades to my bike ... take a look.

Cockpit View

Complete Bike Overhaul

 

[John in CR]

Jonathan,

Very nice bike!

Sorry this is a bit late for when you were soliciting ideas for extra battery place, but I'll post it anyway if you decide to go full stealth. It looked like you had more room in the triangle, then a molded carbon fibre box is plenty strong to go under the downtube. Though the added batteries areas are in pink, yellow to fully fill the triangle, and black under the downtube for invisibility could be made seem integral to the bike frame. Oh well, it's an idea if you go for a version 2.

John

 

[tropmonky]

Very nice looking setup there!! Thanks for the battery and charger info as well.

Kyle