Got my new Speed Meter
07-06-2005, 10:01 PM
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Got my new Speed Meter
I was wonderin. Does the speed meter really give accurate readings. I want to know because I want to know if my car is going as fast as the meter says.
07-07-2005, 01:48 AM
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RE: Got my new Speed Meter
that is not acurate at all tlk to the company, get mad, and get a free one, and tlk to duratrax about the recorded speed not on the box usually a lie
07-07-2005, 02:57 AM
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RE: Got my new Speed Meter
you also need to make sure that it is set up correctly and that you have the right measurments set up into it for it to calculate the speed, i would rather it read a little slow than fast at least you kow its close and not telling you something its not doing LOL i have one on my NTC3 and it is pretty accurate (within about 5 mph) i had it clocked here on post doing 44 adn i think my venom meter read like 47-48 so its not too bad
07-07-2005, 03:06 AM
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RE: Got my new Speed Meter
ORIGINAL: InfinitySpeed04
I was wonderin. Does the speed meter really give accurate readings. I want to know because I want to know if my car is going as fast as the meter says.
I was wonderin. Does the speed meter really give accurate readings. I want to know because I want to know if my car is going as fast as the meter says.
With it I get 35mph or 56km/h with my ultima buggy. But since the tyre expansion is not accoundted for i'd say it's doing closer to 40mph. It's running a ported O.S. .12, and is geared for acceleration rather than top speed.
To set up the speed meter, lay a few feet of masking tape down on a bench or table top, and put a mark on the end of the tape where you wish to start rolling the car.
Now place the car down so the rear axle is directly inline with the line you have just drawn. Then push the car so the sensor on the tranny makes 5 complete rotations. and mark the tape where you finished (make sure it's directly below the axle once again).
Repeat rolling the vehicle 2 more times and you should have 3 small marks very close to each other.
Measure all 3 distances and take the average, THEN make sure you divide the answer by 5, because you made the tranny do 5 rotations.
Enter the data into the speed meter..
Record the reading and the type of tyre, this way you can easily adjust it for different tyres with different profiles.
07-07-2005, 07:25 AM
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RE: Got my new Speed Meter
ORIGINAL: InfinitySpeed04
I got a nitro evader st and it is sayin its going about 28-30mph
I got a nitro evader st and it is sayin its going about 28-30mph
From this thread:
http://www.rcuniverse.com/forum/m_2721707/tm.htm
I figured out the gear train for the Street force GP2, which RCCA clocked at 53.2mph. Believe it or not, that works out to 34750 rpms! High, but not a crazy number you can just throw out cuz it's silly. The only thing that i'm not positive about is the GP2's tire diameter, but i think 61mm is pretty darn close. Someone correct me if they can.
A ST (or buggy) is going to have a greater load on the motor than a TC, so realistically, we can probably say it runs at 32k or 33k rpms at peak.
So, speed numbers, for 4" diameter wheels, at 33k rpms (might as well)
Stock evader St 60T spur 15T clutchbell - 34 mph
With BX's 57T spur and 17T clutchbell - 40.5 mph
With rayray's 56T spur and 21T clutchbell - 51 mph
These would be near absolute peak numbers, that you will likely never exceed, but really they're pretty reasonable, and follow most of what people have been reporting.
Anything not optimal would lower these numbers, such as being a hot day, higher altitude, high humidity, poor maintenance causing greater drag on the drivetrain, non-optimal surface to run on (grass rather than pavement or hard pack), or improper tune.
Any one of these could easily bring the engine down to a more reasonable 30k, so here's the numbers on 30k, which is what you can likely expect on a decent to good day, rather than a perfect day.
Stock evader St 60T spur 15T clutchbell - 30.9 mph
With BX's 57T spur and 17T clutchbell - 36.8 mph
With rayray's 56T spur and 21T clutchbell - 46.3 mph
Both these sets of numbers agree with Frost and Jakjr's radar data perfectly.
So there it is, the DTX .18 probably peaks at around 35k with no load, and in practice, runs in the 29k-32k range and at 33k on a perfect day.
07-07-2005, 10:02 PM
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RE: Got my new Speed Meter
just a quck reply here, i am a part time duputy sheriff and i have access to a handheld radar gun
I have a nitro evader running an O.S. .15cvx . i clocked my evader at 49 m.p.h. in a short distance run of about 50 feet
keep in mind this was on a nice flat street at about 2 a.m. with nice cool air ( i probably could have leaned it out a bit and gotten more speed out of it but i didnt have the time to mess with it), it is still the stock gear ratio with the clutch bell and spur gear
I have a nitro evader running an O.S. .15cvx . i clocked my evader at 49 m.p.h. in a short distance run of about 50 feet
keep in mind this was on a nice flat street at about 2 a.m. with nice cool air ( i probably could have leaned it out a bit and gotten more speed out of it but i didnt have the time to mess with it), it is still the stock gear ratio with the clutch bell and spur gear
07-08-2005, 07:39 AM
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RE: Got my new Speed Meter
suprcop67:
Unless you have tires on that are considerably larger than the stock 4" diameter tires then there is no way your evader got even close to 49 mph with an OS .15 CV-X (or any engine for that matter)
Maybe your radar gun doesn't work well on small objects, or there is some other explanation, but no way, no how.
Specs from OS (manufacturer specs are usually overrated)
Engine .15 CV
Displacement 0.152 (2.49 cc)
(cu in) Bore 0.598 (15.2 mm)
(in) Stroke 0.539 (13.7 mm)
(in) RPM 3,000-30,000
Output (HP@rpm) 0.68 @ 29,000
To make a stock evader go 49 mph, ANY engine would have to rev at 48,000 rpm. That's 18,000 rpm over the maximum rpms stated by OS for your engine.
Even with masher 2k's on (one of the largest tires that fit a ST), your engine would still have to spool up to 39,000 rpm to go 49. I doubt that mill would even hit 30,000 with mashers on.
And to do it in a 50 foot run? C'mon now.
Go back and read the post i linked. It gives a good idea of what speeds an evader is capable of.
disclaimer: this post was not meant to offend, only refute misinformation.
Unless you have tires on that are considerably larger than the stock 4" diameter tires then there is no way your evader got even close to 49 mph with an OS .15 CV-X (or any engine for that matter)
Maybe your radar gun doesn't work well on small objects, or there is some other explanation, but no way, no how.
Specs from OS (manufacturer specs are usually overrated)
Engine .15 CV
Displacement 0.152 (2.49 cc)
(cu in) Bore 0.598 (15.2 mm)
(in) Stroke 0.539 (13.7 mm)
(in) RPM 3,000-30,000
Output (HP@rpm) 0.68 @ 29,000
To make a stock evader go 49 mph, ANY engine would have to rev at 48,000 rpm. That's 18,000 rpm over the maximum rpms stated by OS for your engine.
Even with masher 2k's on (one of the largest tires that fit a ST), your engine would still have to spool up to 39,000 rpm to go 49. I doubt that mill would even hit 30,000 with mashers on.
And to do it in a 50 foot run? C'mon now.
Go back and read the post i linked. It gives a good idea of what speeds an evader is capable of.
disclaimer: this post was not meant to offend, only refute misinformation.
07-08-2005, 10:09 PM
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RE: Got my new Speed Meter
HA, too bad you bought one, honestly. Those aren't anywhere close to accurate. The slightest bit of wheel spin could send that thing way above 40 mph... oh well. They give you a general idea of how fast you might be going, thats what counts 
07-09-2005, 07:51 PM
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RE: Got my new Speed Meter
ahh man im sory i member some one telling me one worked but i forgot im sory man if u find out tell me and get the bx sper gear that one is faster than the ST sper 
07-11-2005, 12:13 AM
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RE: Got my new Speed Meter
Hey gives me an idea of how fast I'm going. and its not a POS its pretty much better than just guessing it. I really dont have the money for a radar gun at the moment.
07-11-2005, 06:46 AM
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RE: Got my new Speed Meter
[link=http://www.dynotech-racing.com/partsSearch.php?term=evader]Evader Threaded Clutch bell[/link] will give you a great selection of pinion gears.
07-11-2005, 11:03 AM
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RE: Got my new Speed Meter
The VSM will never give accurate readings in a truck when set correctly by manual. It mainly only works for Onroad sedans. The reason being, obviously, tire expansion. My VSM told me my Fantom FR18 powered X-Cellerator was only going 38mph. I know FOR SURE that it was going at least 55. What you can do is if you have access to a radar gun, clock your trucks top speed. Then you just keep upping the VSM setting until it tells you your top speed is whatever the radar confirmed. Obviously, this will screw up its low speed readings, but who cares?
07-11-2005, 11:30 AM
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RE: Got my new Speed Meter
We have cops always coming into my neighbor hood and they are really nice so Ill ask them if they would radar my car for me. Hey maybe afterward theyll give me a speeding ticket.
07-11-2005, 11:53 AM
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RE: Got my new Speed Meter
Does anyone know if this clutch bell will fit on an evader?
[link=http://www2.towerhobbies.com/cgi-bin/wti0001p?&I=LXDHL8&P=7]Clutch Bell[/link]
[link=http://www2.towerhobbies.com/cgi-bin/wti0001p?&I=LXDHL8&P=7]Clutch Bell[/link]
07-11-2005, 02:55 PM
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RE: Got my new Speed Meter
ORIGINAL: InfinitySpeed04
I was wonderin. Does the speed meter really give accurate readings. I want to know because I want to know if my car is going as fast as the meter says.
I was wonderin. Does the speed meter really give accurate readings. I want to know because I want to know if my car is going as fast as the meter says.
Check this out....
[link=http://www.radiocontrolzone.com/cars/calculator.asp]Speed Calculator[/link]
07-20-2005, 10:12 PM
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RE: Got my new Speed Meter
i just got back to check out this post, i might be wrong about the speed i clocked but this is the procedure we used, we calibrated the radar with tuning forks ( as is required at the beginning of each shift for legal reasons) the street was empty and flat with no passing traffic to clock by mistake,in three different passes it was within 1-2 mph of 49 mph,i went back and measured the distance it was just a shade over 100 feet to get to speed, believe me or not but but that is the results that i came up with your math may be right but i race this truck every weekend and i know its not slow i beat nitro rustlers on a regular basis
