Ignition coils, high pressure fuel pump, and injector solenoids, and engine control electronics all require power. In carburetor days, it was only the ignition coils. I think those must be the coils that vtballeng was referring to. If current is lower, it could require increased time (dwell) to get the ignition coils 'loaded' and ready to generate the spark at the plug.
Converting to a Total Loss System...
- Thread starter ScottLevy
- Start date
BigKid
New Member
^^^^ I agree with all of that. Also most fuel injection computers either shut down or go haywire if they fall below a certain voltage. Ducati's wont even start below 12.7 volts or something like that. COmputer wont even try to fuel the injectors. Might be 11.7 volts, but its up there
geekmug
New Member
After I laid down my bike at Putnam a few weeks ago, my cheap plastics shattered and I destroyed the rectifier wiring harness and I was forced to operate at a total loss for the rest of the weekend. And then a week later at Mid-Ohio, I found out that my stator had a short and was only getting about half-output. From the experience, my advice: don't.
I was unable to keep ahead of it charging it between sessions all day. My biggest issue, after I became religious about getting it on the charger immediately, was that by the end of the day, starting the bike was a one-shot deal. If you were racing, then whatever, you only need to start it once. But, this is a track day, and you might find yourself sitting for extended periods of time (e.g., trying to have a conversation with a CR after a session), and you will find out that your battery is no longer strong enough to start the thing. This happened to me a few times, and I had to push my bike across the paddock.
I simply cannot imagine the potential performance gain would be worth the completely obnoxious failure modes of a total loss system. (I just bought a new stator, because I'm not gonna keep doing it.)
geekmug
New Member
I'm not sure what the amp-hour rating of those cells are, it's certainly possible that it's higher but I really doubt it. There is/was a guy on the 600rr.net forum that was selling these things in a prepackaged form and the numbers he cited only rate them as 2 to 3 Ah batteries in the end. The biggest one he had probably was probably around 4 to 5 Ah. Most bikes are coming with 8 Ah batteries, so I'd honestly expect it to be even worse with such a battery pack.
The flywheel is rotating around the stator. The flywheel has permanent magnets in it and the stator has coils of wire that are energized by them passing by. The real loss of power is that the flywheel is doing work against the stator (energizing the coils sucks energy from the system). The stator is sucking several hundred watts of energy from the engine all of the time (my bike is rated at 342W @ 5k RPM). That's the loss of 0.5 HP. It only goes up as the engine is spinning faster.
You could disconnect the stator from the rectifier and you will get that power back (there is no work done when it's an open-circuit) and you will find out how long your battery can last. No cracking of cases or commitments required to find out what it's like. You obviously are still carrying around the weight of the stator, but skip the cheeseburger meal that day and you'll have a pretty good idea of what difference there is (not much).
BigKid
New Member
The a123 cells will do much worse in a total loss system, They can not be used in that application. AT ALL
They go flat quicker even though they will maintain a higher voltage longer, once they go they go fast. And they CANT be quickly recharged so sitting between sessions trying to recharge them will fry them, they need very slow charge rates, like a trickle charger, adn you cant overcharge them or they will go bad, quickly.
They go flat quicker even though they will maintain a higher voltage longer, once they go they go fast. And they CANT be quickly recharged so sitting between sessions trying to recharge them will fry them, they need very slow charge rates, like a trickle charger, adn you cant overcharge them or they will go bad, quickly.
ScottLevy
Control Rider
Right, but I thought the whole point of the A123 pack is that you are able to charge it quickly at high current (10amps) in some cases? I agree they drop off quickly when they're done, but there are tons of threads on this subject and how putting together a pack that will last a 20 minute session would be able to be recharged in the next 30-40 minutes. Yes you'd have to take care to balance them properly if you want longevity, but for a total loss system, I would have thought that is exactly what you want...
Here's a thread:
http://forums.13x.com/showthread.php?p=3046895
The builder claims to be able to charge an 8 cell pack from 0 in 45 minutes. I would assume that you wouldn't be completely dead in 20 minutes...
BigKid
New Member
Lithium batteries require a slow charge rate. they hate to be overheated, overcharged, both products of quick charging them. I could look up the charge rate but i,m too lazy. It is basically a trickle charge though and any manufacturer that suggests anything faster other than when completely discharged and cool is not correct.
Anyone notice how their new Dewalt chargers for lithium take twice as long to charge a lithium or regular battery and how they say if you put a lithium in a regular charger it will destroy it. Well, A123 batteries are exactly the same thing dewalt lithium battery packs use.
Anyone notice how their new Dewalt chargers for lithium take twice as long to charge a lithium or regular battery and how they say if you put a lithium in a regular charger it will destroy it. Well, A123 batteries are exactly the same thing dewalt lithium battery packs use.
vtjballeng
New Member
I could write for days on the issue but the direct answer is ignition coils require a charge event every 720 degrees of cylinder rotation in an SI engine and IR=V.
Fuel injection and ignition system will be affected in the ways described in my prior post. Charging system will be inactive.
vtjballeng
New Member
Ohms law is IR=V which is what you are describing.
Voltage compensation tables are both necessary, well understood and well established in electronic fuel injection going back to inception. The increased ignition coil charge times to reach current saturation and increased injector opening times can both still effect running performance despite voltage compensation tables. As a general rule, modern systems are not intended to be used at peak power for extended periods on reduced voltage. There are many more good reasons not to do total loss systems that exceed the scope here. The only place total loss is appropriate in a modern, production system is in short duration or drag racing.
Carnag3
New Member
ScottLevy
Control Rider
That may be true of Lithium Ion batteries, but it appears it's not true of Lithium Iron Phosphate batteries. LiFePo4
http://en.wikipedia.org/wiki/Lithium_iron_phosphate_battery
This guy Jim, has been making batteries for guys specifically for total loss systems. He has tested these out under all kinds of situations regarding charging/discharging. He made this video of a 4 pack specifically designed with a fail point and it did not hurt the pack after 20 seconds of constantly holding down the starter:
http://www.youtube.com/watch?v=F0xsOHHWmiU
Here's a full line of his products with guys already proving that using these packs in a total loss system is working out.
http://forums.13x.com/showthread.php?t=243197&highlight=a123&page=11