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Brandon G wrote:Boost in your 2WD buggy? I thought the general rule of thumb in the classes running 17.5 was to do without it.

Every year I've looked into attending I was sure it was blinky too.

Erich Reichert wrote:Ed are you not coming this year? But who will win the cars i have to give away?

Don't worry, Rob will be there. Best reserve a kit for him... lol

So I'm trying to charge up my 3800 and 4000 mah, 7.4V/2S lipos for the first time before the race and not sure what to do/how to cycle them so I figured I'd ask rather then risk a leak/explosion. I never used lipos before. I'm using a new Imex balance charger that can charge any type of battery and I double checked my settings. I've had the batteries for a few years, never used them or ran a charge through them but when I hooked them up to the car the motor ran full speed (but no steering...?). I tried discharging the 3800 mah for an hour but the voltage was still reading 7.35-7.38 the entire time. Does it take longer than that to discharge? Should I discharge them fully and then charge them again? Am I doing something wrong? Thanks.

Charlie don't surf wrote:

Brandon G wrote:Boost in your 2WD buggy? I thought the general rule of thumb in the classes running 17.5 was to do without it.

Every year I've looked into attending I was sure it was blinky too.

It says on the first page that electronics are open. I can run just as fine without boost, but if it's allowed, I'd like to try it and see how it goes. Just something new to play around with...

R/Cat wrote:So I'm trying to charge up my 3800 and 4000 mah, 7.4V/2S lipos for the first time before the race and not sure what to do/how to cycle them so I figured I'd ask rather then risk a leak/explosion. I never used lipos before. I'm using a new Imex balance charger that can charge any type of battery and I double checked my settings. I've had the batteries for a few years, never used them or ran a charge through them but when I hooked them up to the car the motor ran full speed (but no steering...?). I tried discharging the 3800 mah for an hour but the voltage was still reading 7.35-7.38 the entire time. Does it take longer than that to discharge? Should I discharge them fully and then charge them again? Am I doing something wrong? Thanks.

Don't ever fully discharge a lipo. it will destroy the cell! The 2S lipo should be stored at a voltage around 7.5 volts. If you are getting full throttle with no transmitter throttle it sounds like an ESC problem. Like no throttle input from the receiver or a blown ESC from plugging in the battery backwards. reversing the input polarity from the battery will fry the internal circuit in the speed control.

jberlenbach wrote:

R/Cat wrote:So I'm trying to charge up my 3800 and 4000 mah, 7.4V/2S lipos for the first time before the race and not sure what to do/how to cycle them so I figured I'd ask rather then risk a leak/explosion. I never used lipos before. I'm using a new Imex balance charger that can charge any type of battery and I double checked my settings. I've had the batteries for a few years, never used them or ran a charge through them but when I hooked them up to the car the motor ran full speed (but no steering...?). I tried discharging the 3800 mah for an hour but the voltage was still reading 7.35-7.38 the entire time. Does it take longer than that to discharge? Should I discharge them fully and then charge them again? Am I doing something wrong? Thanks.

Don't ever fully discharge a lipo. it will destroy the cell! The 2S lipo should be stored at a voltage around 7.5 volts. If you are getting full throttle with no transmitter throttle it sounds like an ESC problem. Like no throttle input from the receiver or a blown ESC from plugging in the battery backwards. reversing the input polarity from the battery will fry the internal circuit in the speed control.

Thanks, no I have full throttle control and ESC is working fine I just meant that the battery seems fully charged even though I've had them for a couple of years and never charged them but that's probably because they have 7.35-7.38v stored in them. Perhaps I'm not use to the power increase from a Lipo pack either and that's why it seems fully charged when it really isn't. If storage volts should be around 7.5v and mine are at almost 7.4v it sound like I don't have to discharge and can simply charge them up. Is that correct?

R/Cat wrote:

jberlenbach wrote:

R/Cat wrote:So I'm trying to charge up my 3800 and 4000 mah, 7.4V/2S lipos for the first time before the race and not sure what to do/how to cycle them so I figured I'd ask rather then risk a leak/explosion. I never used lipos before. I'm using a new Imex balance charger that can charge any type of battery and I double checked my settings. I've had the batteries for a few years, never used them or ran a charge through them but when I hooked them up to the car the motor ran full speed (but no steering...?). I tried discharging the 3800 mah for an hour but the voltage was still reading 7.35-7.38 the entire time. Does it take longer than that to discharge? Should I discharge them fully and then charge them again? Am I doing something wrong? Thanks.

Don't ever fully discharge a lipo. it will destroy the cell! The 2S lipo should be stored at a voltage around 7.5 volts. If you are getting full throttle with no transmitter throttle it sounds like an ESC problem. Like no throttle input from the receiver or a blown ESC from plugging in the battery backwards. reversing the input polarity from the battery will fry the internal circuit in the speed control.

Thanks, no I have full throttle control and ESC is working fine I just meant that the battery seems fully charged even though I've had them for a couple of years and never charged them but that's probably because they have 7.35-7.38v stored in them. Perhaps I'm not use to the power increase from a Lipo pack either and that's why it seems fully charged when it really isn't. If storage volts should be around 7.5v and mine are at almost 7.4v it sound like I don't have to discharge and can simply charge them up. Is that correct?

Yes, lipos have a lot more power and they hold their charge in storage quite well. I tend to charge mine and then discharge them to 7.5 volts a couple times a year for the packs I don't run on a regular basis.

Thanks, no I have full throttle control and ESC is working fine I just meant that the battery seems fully charged even though I've had them for a couple of years and never charged them but that's probably because they have 7.35-7.38v stored in them. Perhaps I'm not use to the power increase from a Lipo pack either and that's why it seems fully charged when it really isn't. If storage volts should be around 7.5v and mine are at almost 7.4v it sound like I don't have to discharge and can simply charge them up. Is that correct?[/quote]

Yes, lipos have a lot more power and they hold their charge in storage quite well. I tend to charge mine and then discharge them to 7.5 volts a couple times a year for the packs I don't run on a regular basis.[/quote]

OK, great. I'm going to charge them today and see what happens. If they start at 7.4v what can I expect it to go up to when completely charged and how long will the charge take? Also, I've been watching some youtube videos on balance charging (balancing the cells) and hearing different things. Some say to balance-charge every charge while others say only balance-charge every 4-5 charges. It doesn't seem like the cells have to be balanced EVERY charge but what do you think?

R/Cat wrote:Thanks, no I have full throttle control and ESC is working fine I just meant that the battery seems fully charged even though I've had them for a couple of years and never charged them but that's probably because they have 7.35-7.38v stored in them. Perhaps I'm not use to the power increase from a Lipo pack either and that's why it seems fully charged when it really isn't. If storage volts should be around 7.5v and mine are at almost 7.4v it sound like I don't have to discharge and can simply charge them up. Is that correct?

Yes, lipos have a lot more power and they hold their charge in storage quite well. I tend to charge mine and then discharge them to 7.5 volts a couple times a year for the packs I don't run on a regular basis.[/quote]

OK, great. I'm going to charge them today and see what happens. If they start at 7.4v what can I expect it to go up to when completely charged and how long will the charge take? Also, I've been watching some youtube videos on balance charging (balancing the cells) and hearing different things. Some say to balance-charge every charge while others say only balance-charge every 4-5 charges. It doesn't seem like the cells have to be balanced EVERY charge but what do you think?[/quote]

they should finish charging at 8.4 volts. balancing once a week is fine

I'm sorry if this has been answered somewhere else, but what time does the track close on Friday and open for practice on Saturday? I know that it normally closes at 7 on Friday and opens at 10 on Saturday. Are there special event hours, or will it be normal time?

85Edinger wrote:I'm sorry if this has been answered somewhere else, but what time does the track close on Friday and open for practice on Saturday? I know that it normally closes at 7 on Friday and opens at 10 on Saturday. Are there special event hours, or will it be normal time?

A couple of us asked and Erich's in the process of checking/confirming times. I've copied/pasted a portion of what Wolcott has on their website below which I assume is accurate and up to date until or unless I hear otherwise from Erich.

"Current Hours are Monday closed, Tuesday 12-6, Wednesday 12-7, Thursday 12-7, Friday 12-9, Saturday 10-5, Sunday 10-5
We currently Run off-road on Tuesday night starting at 7, Friday night starting at 7, and Sunday starting at 11am."

Charlie don't surf wrote:

Brandon G wrote:Boost in your 2WD buggy? I thought the general rule of thumb in the classes running 17.5 was to do without it.

Every year I've looked into attending I was sure it was blinky too.

naw, it's always been open.

i got my rc10 ready over the weekend. as well as my race clod, stadium blitzer and my boy's grasshopper. lol
i want to see how silly a hopper with 2.2's looks going around the track. i also took out the 380 and put in a 540 for him, he thinks it's the fastest thing in the world now.

Good luck on the weekend fellas, have a great race. I hope theres plenty of great vids put up of the action

here in Australia our vintage festival is only a few weeks away

Cheers

Mikey

Good luck guys, hopefully I will see you next year.

Looking forward to seeing some media fellas! Pics Pics Pics!!! Video? Sure!!!