Search found 19 matches

by Canoe
Feb 08 2019 4:53pm
Forum: E-Bike Build Threads / Photos & Video
Topic: High performance & durability Cannondale Semi Recumbent
Replies: 260
Views: 11331

Re: High performance & durability Cannondale Semi Recumbent

> Tubeless tires with sealant are a time-consuming hobby. We already have a hobby. Yup If you do it wrong. Or want to experiment. > Did you ever stop to consider why no other vehicle with pneumatic tires routinely uses the stuff? It's a huge nuisance. There are limited applications where it makes se...
by Canoe
Feb 08 2019 3:03pm
Forum: E-Bike Technical
Topic: Why do Fat-tires have higher rolling resistance?
Replies: 27
Views: 1564

Re: Why do Fat-tires have higher rolling resistance?

A few days ago, mikesee posted a rolldown test of two different 5" tires on snow at 4 PSI, 2 PSI and 0.5 PSI. While the test is for aiding tire selection for the ITI, the results observed illustrate how two tires can be different and how much of a difference PSI makes. https://forums.mtbr.com/fat-bi...
by Canoe
Feb 08 2019 10:45am
Forum: E-Bike Build Threads / Photos & Video
Topic: High performance & durability Cannondale Semi Recumbent
Replies: 260
Views: 11331

Re: High performance & durability Cannondale Semi Recumbent

... Tires must be thick enough to resist goathead and tack punctures. ... Given the various ideas in the thread to address this, I believe it would be far simpler - and has a proven track record - to do what the mountain bike riders do - go tubeless with sealant : Most go tubeless to lose the tube ...
by Canoe
Feb 08 2019 2:11am
Forum: E-Bike Technical
Topic: Why do Fat-tires have higher rolling resistance?
Replies: 27
Views: 1564

Re: Why do Fat-tires have higher rolling resistance?

Assuming the 2inch runs at 60PSI, the 4inch would need 15PSI to have the same tire deformation = same rolling resistance . I think this assumption may need clarification, since, I believe, this is the primary contributor to energy lost between the two. If "same tire deformation" means that the same...
by Canoe
Feb 08 2019 1:12am
Forum: E-Bike Technical
Topic: Fatbike BB torque sensors and weird sizing.
Replies: 2
Views: 277

Q

When first out (March 2014), the Mongoose Dolomite came with a 100 mm BB and a spindle of 189 mm. Some quality YST bearings were nice, but the spindle was soft, and long, and a number of reports of getting bent. But no cartridge BB would fit (with the stock straight crank arms). Then someone figured...
by Canoe
Aug 25 2010 11:20am
Forum: Battery Technology
Topic: connections for? EcityP Smart S5-13 BMS
Replies: 187
Views: 49774

Re: connections for? EcityP Smart S5-13 BMS

ECityPower supplied connection jpg

now we're safe
by Canoe
Aug 25 2010 9:52am
Forum: Battery Technology
Topic: connections for? EcityP Smart S5-13 BMS
Replies: 187
Views: 49774

Re: connections for? EcityP Smart S5-13 BMS

BOMARC Services in Wyoming is your friend... they do real good reverse engineering for dirt cheap prices... even cheaper than dirt if you let them resell the results to others. may have to go there It appears that the cell harness connects as expected, with RC1 through RC12, starting with RC1 to th...
by Canoe
Aug 24 2010 11:52pm
Forum: Battery Technology
Topic: connections for? EcityP Smart S5-13 BMS
Replies: 187
Views: 49774

Re: connections for? EcityP Smart S5-13 BMS

FETs are n-channel doesn't add up putting all Drains to battery negative - must be a different design than the other BMS they make extra R between cell management harness extra lead and dual FETs' Sources doesn't make sense yet may be wrong to assume dual parallel FETs are discharge and the lone pow...
by Canoe
Aug 24 2010 6:39pm
Forum: Battery Technology
Topic: connections for? EcityP Smart S5-13 BMS
Replies: 187
Views: 49774

connections for? EcityP Smart S5-13 BMS

I ordered an ECityPower "smart" BMS from BMS Battery on Aug. 17, 2010, with my custom voltages, currents, etc. It shipped DHL on Aug. 19. It arrived in Ontario, Canada on Aug. 23. The BMS and a few extras were appropriately and safely packaged. There were no hidden fees. The BMS arrived with the bat...
by Canoe
Aug 24 2010 1:54pm
Forum: Battery Technology
Topic: Headway pack: put single temp probe where?
Replies: 12
Views: 773

Re: Headway pack: put single temp probe where?

thanks, In an aside, I ordered a "smart" BMS from BMS on Aug. 17, 2010, with my custom voltages, currents, etc. It shipped DHL on Aug. 19. It arrived in Ontario, Canada on Aug. 23. The BMS and a few extras were appropriately and safely packaged. There were no hidden fees. The BMS arrived with the ba...
by Canoe
Aug 23 2010 4:58pm
Forum: Battery Technology
Topic: Headway pack: put single temp probe where?
Replies: 12
Views: 773

Re: Headway pack: put single temp probe where?

Thanks all, Kapton to a center cell it is. Hadn't thought ahead enough to strain relief any of the wires. Good tip. Thanks! Adrian E-bike. The controller is rated to 800W @36VDC and it's driving a 450W motor chain-drive with a max draw of 16A, which should be a walk in the part for the Headways, esp...
by Canoe
Aug 22 2010 11:54pm
Forum: Battery Technology
Topic: Headway pack: put single temp probe where?
Replies: 12
Views: 773

Headway pack: put single temp probe where?

Sorry, but another newbie question here. I've just assembled my 12S Headway 38120 pack. I've got a HKVT-Monitor/9744 Hobby King Voltage & Temperature Monitor/Alarm. Where exactly should I put the temperature probe? in the air in the middle of the pack for Pack Ambient? against the side of a cell in ...
by Canoe
Aug 22 2010 10:12am
Forum: Battery Technology
Topic: LiFePO4: what makes a Smart charger Smart?
Replies: 18
Views: 1767

Re: LiFePO4: what makes a Smart charger Smart?

would this charger be able to charge an ebikekit lifepo4 with bms? looks similar to the smaller charger they are offering in the site but at much cheaper http://cgi.ebay.com/ebaymotors/ws/eBayISAPI.dll?ViewItem&item=250685827921 I'm not seeing any technical detail about the charger. Only that it's ...
by Canoe
Aug 19 2010 7:42am
Forum: Battery Technology
Topic: LiFePO4: what makes a Smart charger Smart?
Replies: 18
Views: 1767

Re: LiFePO4: what makes a Smart charger Smart?

Thanks for all the replies. Learning lots; see there's more to go. Forgive me, as before this I haven't looked at charging batteries since nicads came out, but don't we need to supply a voltage higher than the cell voltage in order for it to charge? I'm confused about what is happening during the Co...
by Canoe
Aug 18 2010 4:28pm
Forum: Battery Technology
Topic: LiFePO4: what makes a Smart charger Smart?
Replies: 18
Views: 1767

Re: LiFePO4: what makes a Smart charger Smart?

So, for a LiFePO4 ~36V pack (38.40V) charged up to 43.8V, then until current tapers down to 20%-30% CC, when the charging is complete and the battery pack is disconnected from the charger, what is the measured voltage across the battery pack? Or, a single Headway cell, fully charged at 3.65V, once ...
by Canoe
Aug 18 2010 4:11pm
Forum: Battery Technology
Topic: LiFePO4: what makes a Smart charger Smart?
Replies: 18
Views: 1767

Re: LiFePO4: what makes a Smart charger Smart?

thanks ... At the end of the charge cycle this charger will also drop its output voltage a few volts (I don't like the feature)... -R sounds like the behavior of the Soneil SLA chargers So, for a LiFePO4 ~36V pack (38.40V) charged up to 43.8V, then until current tapers down to 20%-30% CC, when the c...
by Canoe
Aug 18 2010 3:13pm
Forum: Battery Technology
Topic: LiFePO4: what makes a Smart charger Smart?
Replies: 18
Views: 1767

Re: LiFePO4: what makes a Smart charger Smart?

I'm building my own pack of Headway 38120 cells. 12S for 38.4Vn 10ah with 43.8Vmax. I've ordered a BMS (43.8Vmax, 24.0 Vmin, 20A Cmax, 30A continuous max). I don't need the higher currents right now, but got them to allow for future use of dumping regen back into the pack and situations where I need...
by Canoe
Aug 18 2010 8:59am
Forum: Battery Technology
Topic: LiFePO4: what makes a Smart charger Smart?
Replies: 18
Views: 1767

LiFePO4: what makes a Smart charger Smart?

So what does a " Smart " LiFePO4 charger do? How would one know the charger they're buying is actually "Smart"? How much risk to charge the string with a Smart charger but without a BMS and then manually balance? Or would it be better to: partially charge then manually balance, partially charge then...
by Canoe
Aug 13 2010 12:11am
Forum: Battery Technology
Topic: 10A (or variable I) charger for 12S Headway 38120?
Replies: 0
Views: 242

10A (or variable I) charger for 12S Headway 38120?

Anyone know of a source for 10A smart charger for a 38.4VDC 12S pack of Headway 38120 cells? Cut-off voltage for the 12S would be 43.8VDC, unless I've got that wrong. Any chance of a selectable current charger? One where you could select 10A when you need it charged "right now", or 5A or 2A selectab...