R/C Tech Forums

Go Back   R/C Tech Forums > General Forums > Electric On-Road

Closed Thread
 
Thread Tools Search this Thread
Old 08-19-2004, 04:22 AM   #616
Tech Regular
 
razzo's Avatar
 
Join Date: Aug 2001
Location: Crappy MN weather!
Posts: 426
Send a message via Yahoo to razzo
Default

mythical speed keeps changing....

originally 68, then some other number, now sig says 70+, on other board it's 82 (was this before the new magical 64,000rpm motor?)
razzo is offline  
Old 08-19-2004, 05:38 AM   #617
Tech Fanatic
 
Cardboard's Avatar
 
Join Date: Feb 2004
Location: Flushing,NYC
Posts: 843
Send a message via AIM to Cardboard
Default

...which brings me to my favorite quote on rctech to date.
Quote:
Originally posted by ajg
Also, if I add 4 more cells to the battery pack it will get it to about 120mph, and yes people have got there micros over 100mph.
Cardboard is offline  
Old 08-19-2004, 06:38 AM   #618
Tech Elite
 
Join Date: Jul 2004
Posts: 2,416
Trader Rating: 7 (100%+)
Default Which brings the question

Quote:
Originally posted by razzo
mythical speed keeps changing....

originally 68, then some other number, now sig says 70+, on other board it's 82 (was this before the new magical 64,000rpm motor?)
What dyno are you using anyways, ajg?
071crazy is offline  
Old 08-19-2004, 07:00 AM   #619
ajg
Registered User
 
ajg's Avatar
 
Join Date: Jul 2003
Location: albuquerque nm
Posts: 924
Default

Quote:
Originally posted by Liam_Davies
I'm suprised we hadn't figured this out before...

Simple mistake on Ajg's part... he's clearly mixed up mph with km/h, so that 80mph is probably 80km/h...

Ajg, why don't you find a more secluded place to do your speed runs, instead of in the street; where it is potentially dangerous and you could get sued if you hit somebody. I don't know how it works in the US, but when you join the BRCA (governing body) you get insurance over that, I think the US governing body is ROAR (correct me if i'm wrong), and I would think they would have you insured, but since you were such a fantastic racer... you would surely already have that.
No, I'm using mph. Also, like I said amny time before, there is no one around (except my cameraman), so no one could get hit!
ajg is offline  
Old 08-19-2004, 07:01 AM   #620
ajg
Registered User
 
ajg's Avatar
 
Join Date: Jul 2003
Location: albuquerque nm
Posts: 924
Default

Quote:
Originally posted by razzo
For anyone using Venom speed reader to measure speed.....

Isn't magnet and sensor suppose to be mounted to your spur/diff to get a legit reading? looks like LOT, including ajg's are set to read from the wheels/axle, not the spur/diff. Even if it's mounted on the spur/diff, how are you guys calculating for wheel slippage, or wheel leaving the ground? even if your car catches air for a fraction of a sec, with throttle peg'd it would spin faster than it would if it was making contact with the ground. I think R/C car magazine mentioned this when they did their review on it (I beleive example was with a buggy going off a jump. it gained speed in air, when they had trottle pulled)

ajg, did you consider any of this when you posted top speed of 82mph? with chunked foams?
Yeah, but my tires don't balloon, so I can mount it on the driveshaft.
ajg is offline  
Old 08-19-2004, 07:06 AM   #621
ajg
Registered User
 
ajg's Avatar
 
Join Date: Jul 2003
Location: albuquerque nm
Posts: 924
Default

Quote:
Originally posted by razzo
mythical speed keeps changing....

originally 68, then some other number, now sig says 70+, on other board it's 82 (was this before the new magical 64,000rpm motor?)
My "official" run was 70mph. Now I'm trying out the 8-cell battery pack. My test run was 54mph, and my first successful run was 60mph (with the new 8-cell pack). I need to run it farther for a higher top speed.
ajg is offline  
Old 08-19-2004, 07:23 AM   #622
Tech Master
 
Euge's Avatar
 
Join Date: Nov 2002
Posts: 1,429
Trader Rating: 5 (100%+)
Default

Quote:
Originally posted by studysession
Euge - Where did you get those pics from? As I stated before, I am working on beating the world speed record and I do a lot of research on the subject. I have not seen those before.
There's a huge hobby show every year here in Chicago. I took those pics myself. It was pretty cool, they let me take the top off and handle the cars. Those pics were from last Fall at the AE booth.

ajg- give it up. The only thing you've accomplished is making yourself look like an @ss

Last edited by Euge; 08-19-2004 at 07:28 AM.
Euge is offline  
Old 08-19-2004, 07:32 AM   #623
ajg
Registered User
 
ajg's Avatar
 
Join Date: Jul 2003
Location: albuquerque nm
Posts: 924
Default

Quote:
Originally posted by Cardboard
...which brings me to my favorite quote on rctech to date.
Mathmaticly, taking 25% off for drag, it would go that fast. I'm not saying I or anyone else hit 120 though.

Euge: give it up? It fun to watch you guys post. Makes me laugh to. Anyway, I have my camera man today after school, so I'll try another video.
ajg is offline  
Old 08-19-2004, 07:42 AM   #624
Tech Elite
 
GundamWZero's Avatar
 
Join Date: May 2004
Location: Ft. Bliss, Texas
Posts: 4,718
Trader Rating: 4 (100%+)
Send a message via MSN to GundamWZero Send a message via Yahoo to GundamWZero Send a message via Skype™ to GundamWZero
Default

You know I was looking thru that thread........that is when I really started posting!!! Even though those "other guys" tried to throw mathematics at the situation, they never added the weight to the equation.....all they can holla is aerodynamics; and that was just a guess at that! Then, there was a handleing issues at high speeds. That thread would have been dead then..............

But he posted a 80 mph run.


And all hell broke loose! All the math geniuses disappeared........
Simply put, there is no way.....that much power will ruin the motor; it'll cook the winds, strip gears, sling foam, whatever.

I still like to see him try, but he will not have the range.

You need to find those guys who said it was possible; lets add more "shrimp on the barbie"!!!!
__________________
"People tend to get upset because they don't get what they ask for... then complain when they get what they deserve." - R.E.Jacobs

‎"We fight not because we hate what's in front of us...
We fight to protect whats behind us."
GundamWZero is offline  
Old 08-19-2004, 09:03 AM   #625
Tech Elite
 
Join Date: Jul 2004
Posts: 2,416
Trader Rating: 7 (100%+)
Default Mathematically, you're wrong

Quote:
Originally posted by ajg
Mathmaticly, taking 25% off for drag, it would go that fast. I'm not saying I or anyone else hit 120 though.

Euge: give it up? It fun to watch you guys post. Makes me laugh to. Anyway, I have my camera man today after school, so I'll try another video.

You're looking at air resistance as if it were some sort of linear relationship to velocity. You appear to imply that 33 percent more voltage=33percent more power=33 percent more speed. This is clearly wrong. Wind resistance increases exponentially with velocity. You can see this clearly in full-size cars. A bunch of cars with 400 whp will hit about 190 mph. But, that doesn't mean that adding on 400 whp will mean a top speed of 380 mph. With your same logic, you'll break the land speed record with about 80 cells.
071crazy is offline  
Old 08-19-2004, 09:16 AM   #626
Tech Adept
 
Join Date: Aug 2003
Location: Teesside, UK
Posts: 138
Default

Quote:
No, I'm using mph. Also, like I said amny time before, there is no one around (except my cameraman), so no one could get hit!
No offense here, but don't you think you should have some form of insurance?

If your car really is doing those speeds, can you imagine hitting someone? In America, the amount of people being sued for stuff like that is immense, be sensible and get some insurance...

Ajg, you remind of the boy racers who claim an air filter and exhaust backbox will give you a sub 4 second 0-60 and a top speed that millenium falcon would be proud of... all from a little hot hatch...
Liam_Davies is offline  
Old 08-19-2004, 09:24 AM   #627
Tech Elite
 
GundamWZero's Avatar
 
Join Date: May 2004
Location: Ft. Bliss, Texas
Posts: 4,718
Trader Rating: 4 (100%+)
Send a message via MSN to GundamWZero Send a message via Yahoo to GundamWZero Send a message via Skype™ to GundamWZero
Default

I am wondering where the dyno came from, really. If the hobby store sinced moved (hence that is why you order parts), have you dynoed the motor lately? I've been a regular racer at only two hobby stores Fantasy World and Tacoma R/C Raceway ( which the owner is a sponsered Losi driver), so far and I didn't see anyone with a motor dyno, 'cause if they did, I would have been nagging them all the time!!!

Did you hobby store have it? When was you motor dynoed? Before or after you start using your motor at high amps?
Keep in mind that running the motor, at any given speed, will wear down the comm. You will have to get the comm cut, clean and lube the bearings, clean the can, re-shim the armature, reset the timing, break in the brushes, and finally dyno the motor. Did the motor come packaged with a lable stateing that it put out 68,000 rpms? If so at how many amps?



an inquiring mind wants to know..........
__________________
"People tend to get upset because they don't get what they ask for... then complain when they get what they deserve." - R.E.Jacobs

‎"We fight not because we hate what's in front of us...
We fight to protect whats behind us."
GundamWZero is offline  
Old 08-19-2004, 09:32 AM   #628
Tech Adept
 
Join Date: Aug 2004
Posts: 199
Default

Quote:
Originally posted by razzo
For anyone using Venom speed reader to measure speed.....

Isn't magnet and sensor suppose to be mounted to your spur/diff to get a legit reading? looks like LOT, including ajg's are set to read from the wheels/axle, not the spur/diff. Even if it's mounted on the spur/diff, how are you guys calculating for wheel slippage, or wheel leaving the ground? even if your car catches air for a fraction of a sec, with throttle peg'd it would spin faster than it would if it was making contact with the ground. I think R/C car magazine mentioned this when they did their review on it (I beleive example was with a buggy going off a jump. it gained speed in air, when they had trottle pulled)
When I set my 1st VSM up - I talked to Venom's tech support before doing so. It can be set on, spur - axle - drive shaft many other areas.

I use the VSM and can vouch for it not always being acurate. You can gane a lot of speed if yours wheels spin from loss of traction. Real quick, i can make my VSM say the car is doing over 50MPh just from wheel spin.

If installed correctly, and set correctly. The VSM can be a very acurate tool.
studysession is offline  
Old 08-19-2004, 09:35 AM   #629
Tech Adept
 
Join Date: Aug 2004
Posts: 199
Default

Euge - Do you have any other pics of those cars? If so, will you please email them to me?

Thanks - [email protected]
studysession is offline  
Old 08-19-2004, 09:49 AM   #630
Tech Elite
 
Join Date: Jul 2004
Posts: 2,416
Trader Rating: 7 (100%+)
Default

I've been bugging ajg to tell us what type of dyno and lathe he uses, but I don't think he knows what a dyno and lathe are.

Come on, ajg! We want to learn!


Quote:
Originally posted by GundamWZero
I am wondering where the dyno came from, really. If the hobby store sinced moved (hence that is why you order parts), have you dynoed the motor lately? I've been a regular racer at only two hobby stores Fantasy World and Tacoma R/C Raceway ( which the owner is a sponsered Losi driver), so far and I didn't see anyone with a motor dyno, 'cause if they did, I would have been nagging them all the time!!!

Did you hobby store have it? When was you motor dynoed? Before or after you start using your motor at high amps?
Keep in mind that running the motor, at any given speed, will wear down the comm. You will have to get the comm cut, clean and lube the bearings, clean the can, re-shim the armature, reset the timing, break in the brushes, and finally dyno the motor. Did the motor come packaged with a lable stateing that it put out 68,000 rpms? If so at how many amps?



an inquiring mind wants to know..........
071crazy is offline  
Closed Thread

Similar Threads
Thread Thread Starter Forum Replies Last Post
Hauler bag that holds everything? platinumjason Rookie Zone 6 06-09-2007 09:18 PM
Speed Record 104 mph Drag Car b4maz Electric On-Road 9 04-04-2007 09:45 AM
"Official" Speed Record 134.4mph XrayFK Electric On-Road 14 08-09-2006 05:00 AM
elec car speed record rx3dreams Electric On-Road 12 08-03-2006 01:01 PM
speed record HELLION Nitro On-Road 5 08-23-2004 11:19 PM



Currently Active Users Viewing This Thread: 1 (0 members and 1 guests)
 
Thread Tools Search this Thread
Search this Thread:

Advanced Search

Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off
Trackbacks are On
Pingbacks are On
Refbacks are Off



All times are GMT -7. It is currently 07:42 AM.


We are a participant in the Amazon Services LLC Associates Program, an affiliate advertising program designed to provide a means for us to earn fees by linking to Amazon.com and affiliated sites.
Powered By: vBulletin v3.9.2.1
Privacy Policy | Terms of Use | Advertise Content © 2001-2011 RCTech.net