R/C Tech Forums

Go Back   R/C Tech Forums > General Forums > Nitro Off-Road

Reply
 
Thread Tools Search this Thread
Old 05-04-2009, 07:11 PM   #31
Tech Elite
 
Join Date: Mar 2009
Posts: 3,657
Trader Rating: 5 (100%+)
Default

thanx guys. Going to bed for work at 4 am
dreaux is offline   Reply With Quote
Old 05-04-2009, 11:23 PM   #32
Tech Elite
 
dishsoap's Avatar
R/C Tech Elite Subscriber
 
Join Date: Jan 2009
Location: Tucson, AZ
Posts: 2,457
Trader Rating: 7 (100%+)
Default

Dang this really sucks. I know exactly how you feel. Just when you think you have it something else goes wrong. I have been through it and now after getting another buggy going through it again like I dont know anything about the hobby, which I really dont.

The problems exsists because of this. I am extremely impatient like you and want everything to work now. New people believe that if they throw $1,500 at it than hell I just spent a shit load of money so it should work flawless.

Its amazing what you think is a big deal but is really nothing. What everyone has been saying about going to your track is dead on.

There have been times where I have spent hours in my garage trying to figure it out because I thought is was major problem, just to go to the track and the experienced guy goes "here was the problem that was really not that big of a problem and now its fixed in 5 seconds"

My first buggy I spent 3 days, recharged my roto start baterry 15 times and countless hours trying to just get the dam thing started. I went to the track and it was started in less than a 1 minute. It was the glow plug ignitor.

Bottom line go to your track. You will get great help.
__________________
HobbyTown USA Tucson!!! HobbyTown USA SRS!!!!
dishsoap is offline   Reply With Quote
Old 05-04-2009, 11:25 PM   #33
Tech Elite
 
dishsoap's Avatar
R/C Tech Elite Subscriber
 
Join Date: Jan 2009
Location: Tucson, AZ
Posts: 2,457
Trader Rating: 7 (100%+)
Default

Oh and the best advice that I have ever recived and still trying to do is this.

When you get mad or fustrated, WALK AWAY!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!! TAKE A BREAK AND COME BACK LATER.!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!
__________________
HobbyTown USA Tucson!!! HobbyTown USA SRS!!!!
dishsoap is offline   Reply With Quote
Old 05-05-2009, 12:47 AM   #34
Tech Fanatic
 
savage.25's Avatar
 
Join Date: Aug 2007
Location: Salmon Arm BC
Posts: 929
Send a message via MSN to savage.25
Default

i also know the feeling quite well... when i get pissed off at my savage because the rear end or something wont line up or go back on i wanna throw that $2000 piece of shit across the house/shop etc, but then i think about how much i have into it and decide that its better to walk away, take a break and have a beer or something and a couple hours later come back to it and it usually goes together quite quickly.. since i dont have a track around me, i am lucky enough to have a friend that helps me out quite abit when i cant get that certain part on, or dont know how something goes together..

like everyone's said head to the local track there's gotta be someone there that will help you out. hell i've been swearing at my savage the 3 years that i've had it.. since i've torn it apart a few times i know that i can do it except for the engine stuff... never had one apart yet... oh and im very impatient too.. i hate fucking waiting in line for something or someone at the doctors office or something... its fucking stupid... and if i sit there waiting for someone long enough i'll start getting all tensed up and squirmy trying to find a good sitting position in the chair because my back hurts.. yeah.... i got scoliosis, so sitting/standing too long doesnt go over well...

good luck fixing your so called "piece of shit" RC... haha just kidding..
savage.25 is offline   Reply With Quote
Old 05-05-2009, 02:27 AM   #35
Tech Master
 
GREGORY!'s Avatar
 
Join Date: Jun 2006
Location: Greece
Posts: 1,074
Trader Rating: 1 (100%+)
Default

dreaux go to the track and find one racer to help you.maybe there are many things that you think that are right but they don't.
you can't understand a lot from a forum.
make yourself a good decision!
GREGORY! is offline   Reply With Quote
Old 05-05-2009, 02:53 AM   #36
Tech Regular
 
Join Date: Jun 2007
Posts: 301
Trader Rating: 23 (100%+)
Default

You need to go the track, Don't expect to get tons of help while everyone is racing. Show up way earily or on a practice day. Almost everyone will help but you are more likely to get good help when the guys are not busy getting their own stuff going.

Hang in there. This hobby is much more fun once you are comfortable tuning.

You may be best off getting setting the v spec on the shelf for a while and get a cheap or used engine. It may be more comfortable to make mistakes on an engine that won't bankrupt you to distroy.
pete8541 is offline   Reply With Quote
Old 05-05-2009, 04:14 AM   #37
Tech Elite
 
DOMIT's Avatar
 
Join Date: Oct 2007
Location: Fort Worth, Texas, USA, North America, Earth, Solar System, Milky Way Galaxy, Universe
Posts: 4,034
Trader Rating: 1 (100%+)
Send a message via MSN to DOMIT Send a message via Yahoo to DOMIT
Default

Dreaux,

A couple of things:

1) You want to get heat into the engine during break in. Wrap the head in a piece of aluminum foil, or with a washcloth. You need to get it up to 200+ degrees. (watch the temps, don't go above about 220 though!)

2) What part of Louisiana do you live in? I don't know the other tracks, but Bossier has some really nice helpful folks. It's hard for us to point you to the right people to help you when we can only narrow it down to tracks within a 5 hour drive or so...

3) I doubt you hurt the engine... but for future reference, you NEED a throttle return spring in case your receiver pack dies like it did. Put a rubber band (doubled up) around the high speed needle and the ball link to the throttle servo, so if the power is off it pulls the throttle closed.

If you hurt anything by over-revving it, it would be the con rod.

And you mentioned taking everything apart... did you by chance take out the piston and sleeve? If you did... did you put the piston back in the right way? The LONG side of the piston skirt goes to the rear of the motor. It covers the exhaust port on the compression stroke. If you have it backwards it may still run... but it will run like crap.
__________________
Brad "DOMIT" Smith - I'm not fast, but at least I wreck a lot.
Unsponsored, but I use/recommend: XRay XB9, Alpha A852, Dynamite 053, Airtronics M11, Hitec 5955TG & 7955TG, ABEC 35 clutch and chassis bearings, PTRCRacing shock and diff fluids, Ready Rollers ceramic engine bearings. ** Team Terribles Region 9 coordinator. ** JOIN TEAM TERRIBLES! All racers welcome! PM me for details.
DOMIT is offline   Reply With Quote
Old 05-05-2009, 04:52 AM   #38
Tech Fanatic
 
vladconnery's Avatar
 
Join Date: Jun 2008
Location: Charlotte, NC
Posts: 992
Trader Rating: 35 (100%+)
Default

Here we have a few simple problems that are not very hard to overcome.

1. Lack of patients. This is the root of many rc departures. You can't expect to gain 3 years experience in 2 days.

2. Lack of learning from mistakes. You have ran the buggy in the water twice now. Was the first time not enough!!

3. Lack of utilizing the best source of knowledge. You were at the track and playing with your car in the parking lot. The racers can't see your problems or answer your questions while your in the parking lot. Cause there either in the pit or on the track. The best source of RC info are racers.

4. Lack of planning. You don't have plan. Lack of planning on your part does not constitute an emergency on our part or the lhs owners part. Keep mind the lhs owner has to sell as many $2000 rigs as he can to stay in business. It was not personal it was business.

GET A PLAN!!!!!

a. get your engine running and idling well. This can be accomplished easily at the track.
a1. Make atleast one friend at the track. Make it a point to meet other guys and introduce yourself. Easiest way to accomplish this is to put your car down and marshall for the good and bad drivers. Bad drivers just suck at driving but they generally have some knowledge worth knowing.

b. 1 successful day of practice time on the track. success is simply your car ran without flaming the whole day.

c. Join the track point series and race the whole series. theres generally 2-3 series a year. Each lasting 8-10 weeks. race every race or as many as you can make.
c1. Your sub goal for the first point series is to complete 1 race without being marshalled!!!! Slow is FAAASSSTTTT!!!!!!!!!!!!!!

d. Make 0-2 adjustments to your buggy each race or practice no more than that. You will get lost in what adjustment actually helped you if you do more than that.

Your knowledge of RC'ing will increase in leaps and bounds if you race and hang out in the pit over a single point series. You will quickly become confident in your ability's. Be careful of advice that you get about your set up remember you are a rookie. A veterans set up and skill level is way different than yours. Take your MBX-6's set up to the most basic of setups. You want the most stability and ease of driving possible!!!!!!!!

Most important stay on your plan!!!!!
__________________
KO PROPO EURUS
Kyosho: TKI3, TKIe Tekin RX8 Gen2
vladconnery is offline   Reply With Quote
Old 05-05-2009, 05:52 AM   #39
Tech Master
 
foampervert's Avatar
 
Join Date: Nov 2002
Posts: 1,367
Trader Rating: 5 (100%+)
Send a message via MSN to foampervert
Default Feeling your pain...

hiya!

I know exactly what you mean! Here at our local track, the drivers tend to congregate by brand (mostly buggy brands... somehow engine/controller/batteries/tires dunt come into the picture... you ask me?) and be very clique-ish. It's really odd behaviour, especially for our off-road scene as I used to believe our off-road enthusiasts were a more welcoming bunch. I can understand how this clique-ish behaviour is more pre-valent amongst the on-roaders as they tend to be very competitive.

If the RC scene at your local track is similar, I'd suggest you find other mugen drivers who will be more then willing to help out a fellow mugenite.

I drive kyosho myself but i sometimes feel like a plague-ridden leper... I find it hard to yak and stuff (and this is me with a reputation of being a yapper!) kyosho is like kryptonite to some people apparently.

either that or peeps are just so obsessed with between heats cleanup to have a proper chat.

We do have very muddy races after all... hyucks.

that's MY rant.

-alexander
p.s. I had to run-in, and tune my engine myself too (didn't RC for 2 years and all knowledge went out the window... dunt worry, the RC equipment can take a little abuse). I also bought all the option springs, rollbars, pistons, oils to try but that's cos i love to wrench.
__________________
During heats, i use durex for both front and rear, with Hard inserts.

Sorex, i meant Sorex.
foampervert is offline   Reply With Quote
Old 05-05-2009, 09:18 AM   #40
Tech Master
 
aaron2u's Avatar
 
Join Date: Oct 2008
Location: Terre Haute, IN
Posts: 1,262
Trader Rating: 45 (100%+)
Default

LOL, this thread sounds like my first gas car experience. I can't believe no one is yelling at you for using WD40 in your engine... Just seems like bad idea.

Loss of compression could be caused by the cylinder walls being scored up from inhaling dirty water. It doesn't take much to screw your engine up. They are not designed to allow for anything BESIDES AIR AND FUEL TO BE RUN THROUGH THE ENGINE. Hard lesson learned. I've flooded out engines before (.12's) and have not done any damage. But immediately, I pull the head, back plate and rinse in warm water with a little dish soap and only turning the engine over by hand WHEN ABSOLUTELY NECESSARY!!! I read a post the other day where someone did this then threw it on the starter box to turn over to clean the engine out. WTF? These engines rely on compression to operate.

Seriously, these are NEWBIE mistakes, god knows I made plenty of them...
__________________
Pick me!
aaron2u is offline   Reply With Quote
Old 05-05-2009, 10:06 AM   #41
Tech Champion
 
JAMMINKRAZY's Avatar
 
Join Date: Jun 2007
Location: Pittsburgh PA
Posts: 6,575
Trader Rating: 17 (100%+)
Default

Quote:
Originally Posted by aaron2u View Post
LOL, this thread sounds like my first gas car experience. I can't believe no one is yelling at you for using WD40 in your engine... Just seems like bad idea.

Loss of compression could be caused by the cylinder walls being scored up from inhaling dirty water. It doesn't take much to screw your engine up. They are not designed to allow for anything BESIDES AIR AND FUEL TO BE RUN THROUGH THE ENGINE. Hard lesson learned. I've flooded out engines before (.12's) and have not done any damage. But immediately, I pull the head, back plate and rinse in warm water with a little dish soap and only turning the engine over by hand WHEN ABSOLUTELY NECESSARY!!! I read a post the other day where someone did this then threw it on the starter box to turn over to clean the engine out. WTF? These engines rely on compression to operate.

Seriously, these are NEWBIE mistakes, god knows I made plenty of them...
Not sure about rinsing an engine with water.

WD-40 is OK as long as the crank isn't silicone filled. If it is the wd will eat the silicone. You should really only use fuel, nitro spray and after run oil in an engine. Definately don't want to be putting any more water into an engine. Will only cause parts to rust.
__________________
-Koby Kubrin-
Thanks to my Sponsors:
Serpent America | Team Novarossi | Desoto Racing | Race AKA | Ridgeway Bodies
JAMMINKRAZY is offline   Reply With Quote
Old 05-05-2009, 10:11 AM   #42
Tech Master
 
pyromania's Avatar
 
Join Date: Feb 2009
Location: North Hills, CA
Posts: 1,283
Trader Rating: 18 (100%+)
Default

Quote:
Originally Posted by JAMMINKRAZY View Post
Not sure about rinsing an engine with water.

WD-40 is OK as long as the crank isn't silicone filled. If it is the wd will eat the silicone. You should really only use fuel, nitro spray and after run oil in an engine. Definately don't want to be putting any more water into an engine. Will only cause parts to rust.
+1

Never, I mean never soak your engine in water. I don't really ever use after-run oil since left over oil from the fuel leaves a good coat on all the components.
__________________
Jesse Carrillo
Team Driver For:
TLR | Horizon Hobby | Nitrotane | Spektrum | HandleITHobbies | 818 Designs
pyromania is offline   Reply With Quote
Old 05-05-2009, 10:30 AM   #43
Tech Master
 
aaron2u's Avatar
 
Join Date: Oct 2008
Location: Terre Haute, IN
Posts: 1,262
Trader Rating: 45 (100%+)
Default

Quote:
Originally Posted by JAMMINKRAZY View Post
Not sure about rinsing an engine with water.

WD-40 is OK as long as the crank isn't silicone filled. If it is the wd will eat the silicone. You should really only use fuel, nitro spray and after run oil in an engine. Definately don't want to be putting any more water into an engine. Will only cause parts to rust.
My bad, should have elaborated... warm soapy water, then lube with after run oil... if something went real haywire, i'll pull the carb apart and clean, but usually just pull the carb and rinse everything off and out throughly.

To the O/P, this really is a learning process. Be patient. I've got enough experince to sport tune an engine, but last week I was at the track and it got the best of me. Didn't know the factory settings on my Werks .21TL 7 port, and EVERYTHING was out of whack. Didn't know where the mid adjustment needed to be, and I was trying to tune the engine with it flush with the carb housing. Doesn't matter where your high and low is if your mid isn't even in the ballpark!

FWIW the last engine I ruined was because of flooding out with icy water, but the ruined part came from lazyness and waiting to clean it out cause I didn't care at the time. ( I thought I was giving the car away, engine not included.)
__________________
Pick me!
aaron2u is offline   Reply With Quote
Old 05-05-2009, 10:35 AM   #44
Tech Regular
 
Joe_Racer's Avatar
 
Join Date: Sep 2006
Location: Scottsdale, Arizona
Posts: 298
Trader Rating: 31 (100%+)
Default

This may help, but +1000 on going to your local track. Where I race there are lots of guys that are knowledgeable and always willing to help.

Tuning tech: carb Needle balance

We get dozens of tuning questions from around the world at Paris racing daily, The number one questions is, were do I set my needles on the carb? Unfortunately there is no such thing as a definitive universal setting for any engine!

Every application will have it's own unique requirements, even two IDENTICAL set ups can and most likely will have at least slightly different settings.
Please see tech tips following the article below [from our web site]
I would like to address what seems to be the # 1 mistake we encounter in engine tuning:

Carburetor Needle balance:

It has come to our attention some racers are making the mistake of setting the idle speed opening to wide [high idle] and setting the bottom end too rich! This will give a false normal idle speed even though the speed is set to high because it "loads up" the engine with excess fuel causing the idle to be lower than set!
The end result is a very unstable idling engine that surges and may cut out as full throttle is applied because the over rich bottom end can disguise a too lean TOP end setting!!!

Let's address this a little more in depth! Idle speed opining set too wide: It is possible too set the idle screw adjustment in to far but yet the idle speed is not high! Even though the air regulation [carb barrel or slide] may be set to a position that would normally equal a vary fast idle, the idle is low because the low speed mixture adjustment is set so rich that the engine loads up with excess fuel and the engine goes into what's commonly called a four cycle idle. One tell tail sign of this is if after reving up the completely warmed up engine it tends to idle fast for a few seconds then drops to lower idle speed.

[Here we go again with the written sound effects :-)]
Something like da..da..da..da..da..da..da..da then it drops to da da da da [if it were sheet music it would be like dropping from 8 beats per measure to 4
beats per measure]

If you start leaning the bottom end a little at a time [then repeat the reving up and idle test] and it takes longer before the idle drops your going in the right direction! Eventually as you keep leaning the bottom the idle will stay to high, now it is time to lower the idle to were it belongs by re adjusting the idle screw!

CAUTION!!!!

Now that you have the idle set correctly the top end may be too lean!!!
Keep in mind the fuel does not directly enter the cylinder area like a 4 stroke engine, it enters the crankcase area first then is transferred or pumped up to the cylinder area by the piston movement.
Simply put, the crank case volume can hold much more capacity than the cylinder so it takes some time to burn off the residual fuel.

In other words if the bottom end is to rich the engine will be supplied by this residual fuel briefly and depending on the demand you may be actually be experiencing a lean condition on the top end that can range from:
1. Seems to run well but engine life is short
2. Seems to run well but car continues to get hotter the longer you run to the point of overheat!
3. Seems to run ok on the bottom but sputters starves or strains to gain rpm
4. Seems to run ok on the bottom but when I give full throttle it cuts out or stalls
[An overly rich top end can act the same as 3 & 4 but excessive smoke and oil are usually present with a distinct blubbering sound]

There is no reason for an engine to continually get hotter unless the tune is wrong [classic #2. symptom] or there is a mechanical problem causing more load or drag on the engine as the run continues.
Exception Note: if the weather or track conditions change DRAMATICL Y. {Examples}
A light drizzle starts and the off road track goes from a very dry loose to high traction condition, or during a race a rapid weather front like a ten degree change! It is very important to fully warm up your engine, clutch and chassis before making finale adjustments.
The chassis in most applications also works like a heat sink to the engine so it is important to fully saturate the chassis!!!

I like to start the engine at least 3 or 4 minutes before our qualifier to get some heat in the engine.
[Operate the throttle by hand until you have radio frequency clearance]
It still takes at least 2 to 3 minutes of hard running on the track to fully saturate the chassis!

There is a series of restrictions to control fuel flow at different throttle/air flow positions called needles These are the five basic parts of the carb to concern yourself with:

1.The slide or barrel [regulates the amount of air to enter the engine controlled by the servo]
It simply blocks off the airflow to the engine proportional to how far it is open or closed.
2. The idle/air speed screw [sets the absolute minimum air the barrel/slide can control to maintain idle speed]
It simply is an adjustment screw that comes in contact with the side at the nearly closed/idle position.
3. The high speed needle [regulates maximum fuel flow allowed to enter engine at any throttle position]
It simply is a tapered needle that screws into the fuel flow orifice [an adjustable restriction] .
This maximum fuel flow ideally is adjusted to the correct mixture ratio for the surrounding conditions at WIDE OPEN THROTTLE or WOT
There are two more devices' the low speed or minimum spray bar and the mid range needle that restrict or control the fuel further at less than full throttle.
4. The low speed needle [regulates fuel to engine at idle]
The low speed adjustment simply restricts the flow at idle speed.
If you look down the bore of the carb you will see a long tapered needle [except for Picco torque carbs]
When the carb barrel/slide is closed the larger part or diameter portion of the long tapered needle is inserted into the spray bar, this is what's adjusted when you turn the low speed/minimum adjustment.
It literally moves either the tapered needle OR spray bar farther in or out changing the restriction independent of the barrel/side position.
This leans [more restriction] or richens [less restriction] the flow from the spray bar at idle.
NOTE: some carbs the spray bar is moved and others the needle assembly is moved, both have the same effect.
5. The mid range needle [regulates fuel to engine after idle and before full fuel position.
Notice as you open and close the carb the tapered needle [mentioned above in item 4.] enters into a small tube this is called the spray bar/jet.
This spray bar is were ALL the fuel enters the airflow stream regulated by the high speed, mid range and idle/minimum adjustments!
Normally somewhere between Y2 and % throttle open position the needle is completely out of the spray bar, This is what is called full fuel position or FFP [at this point 100% of the mixture is controlled by the high speed needle.
On many carbs the low speed and midrange are not independently adjustable so the mid rage is a factor of the needle taper and is engineered by the
factory. On some SLIDE carbs there is both independent spray bar and mid range needle adjustments. CAUTION: be very careful with these type carbs!!!
You can identify them easily because there are four adjusting screws!
0ne each for the:
High speed/top end [normally sticks up some what vertical]
Idle/air speed [normally a much smaller screw entering the carb at an angle]
Low speed/minimum [located in the end of the slide OR on the opposite end of the carb body]
Midrange [also located in the end of the slide OR on the opposite end of the carb body]
Note: if there are adjustments on both the slide and the carb body one is an adjustable mid range and the other the low speed!!! Check with the engine manufacture before attempting to adjust these types of carbs!

It is very important not to use the mid screw to adjust the low end by mistake; it is very easy to get the carb way out of sync.

Normally I recommend not attempting to adjust the mid range even if your carb is so equipped, the gains are VERY small and mostly limited to minute midrange drivability/economy changes that only the most sophisticated driver will recognize!

The negative is a carb that is so screwed up only an expert can get it back in tune!
Please note the above descriptions will apply to 99% of the modern car carbs being manufactured as of this writing with the exception of the Picco TORQUE carb that use's no mid range needle at all.
It utilizes a fuel management ramp built into the slide; the carb also has two completely independent fuel delivery spray bars/jets.

I wish I could tell every one exactly how to tune their engine but I cannot!
My hope with this article is if I can help racers to more understand How your carb works, all the other instructions and guides will make more sense!
Best Regards,
Ron
some stuff doesn't apply to our engines today but they are still excellent guidelines to follow as we all learn more about the nitro engine and how to master the art of power extrapulation . i spent a few years learning all this stuff by myself before i ever read any article buut ron is always right on the money

Thanks to Monty for posting this on his engine thread. Ron Paris had no equal when it came to these little engines.
__________________
Jack G.

Mugen MBX-7 Novarossi Plus 4, Mugen MBX-6TR Novarossi P5
RC10 GT2 OS TG, RC10 B4.2 17.5, SC10 FT 13.5, RC10 T4.1 13.5
Joe_Racer is offline   Reply With Quote
Old 05-05-2009, 10:36 AM   #45
Tech Lord
 
Jaz240's Avatar
R/C Tech Elite Subscriber
 
Join Date: Aug 2008
Location: Dwindle city
Posts: 12,492
Trader Rating: 52 (100%+)
Default

It doesn't matter if its warm and soapy, or cold as ice..DO NOT USE WATER TO CLEAN YOUR ENGINE!!!, never. Clean it with fuel and a soft brush, then swab it with after run oil. Water rusts metal..always did..always will
__________________
nothing to see here................................
Jaz240 is offline   Reply With Quote
Reply

Similar Threads
Thread Thread Starter Forum Replies Last Post
Tamiya Championship Series Neil Rabara Racing Forum 21150 Yesterday 08:58 PM
Temp guns - Basic questions noR Offroad Nitro Engine Forum 19 01-27-2013 07:25 PM
2008 IFMAR 1/8 Buggy World Championship - Sept: 15-21 @ The Farm 2 KyLayfield Nitro Off-Road 854 01-12-2009 01:44 PM
ROAR Has a new President BullFrog Electric On-Road 220 12-16-2005 05:49 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 09:11 PM.


Powered By: vBulletin v3.9.2.1
Privacy Policy | Terms of Use | Advertise Content © 2001-2011 RCTech.net