R/C Tech Forums

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

Reply
 
Thread Tools Search this Thread
Old 09-05-2005, 10:07 AM   #1
Tech Rookie
 
Join Date: Sep 2005
Posts: 4
Default rs4 3 evo problem

after breaking the motor in i went and adjusted the carb. there is no power the motor has good throttle response but no top speed , tried to lean car out but no effect



thx
john
chev1 is offline   Reply With Quote
Old 09-05-2005, 10:26 AM   #2
Tech Master
 
Im2lazy's Avatar
 
Join Date: Oct 2002
Location: Hawaii!
Posts: 1,967
Default

Quote:
Originally Posted by chev1
after breaking the motor in i went and adjusted the carb. there is no power the motor has good throttle response but no top speed , tried to lean car out but no effect



thx
john
Check that the plug is good. Plugs go bad quickly. Also, when tuning the motor, do not turn the main needle more than an 1/12 of a turn at a time. If you turn the needle something like half a turn, you will surely have trouble figuring out how to tune your motor.

Just some basic advice. If you need further assistance, just post again.
Im2lazy is offline   Reply With Quote
Old 09-05-2005, 10:32 AM   #3
Tech Rookie
 
Join Date: Sep 2005
Posts: 4
Default

ipretty much have the tunning down wot there is smoke but there is no speed adjusted the 2 speed just nothing there like something is holding it back but i can push the car freely im using an os a3 glow plug so there should not be a problem and using trinnity monster horsepower 20% fuel iot kinda sounds like an clutch issue
chev1 is offline   Reply With Quote
Old 09-05-2005, 10:53 AM   #4
Tech Master
 
Im2lazy's Avatar
 
Join Date: Oct 2002
Location: Hawaii!
Posts: 1,967
Default

Quote:
Originally Posted by chev1
ipretty much have the tunning down wot there is smoke but there is no speed adjusted the 2 speed just nothing there like something is holding it back but i can push the car freely im using an os a3 glow plug so there should not be a problem and using trinnity monster horsepower 20% fuel iot kinda sounds like an clutch issue
If you think its the clutch, take the dude apart. HPI's standard 2shoe clutches are not known to last long. If it is the clutch, grab MIP's clutch for HPI vehicles.

Have you physically checked the glow plug? They can last for months, or they could go sour in just one tank... and as for tuning, unless I were someone like Steve Odonnel, I'd have to admit to myself that engine tuning is one hell of an issue... seeing as you must regard the plug, weather, needle settings, clutch settings, head clearance, gear mesh, blah blah blah, and especially the vehicle's performance. There are just so many variables that affect our vehicles' performance that may or may not be considered part of engine tuning.
Im2lazy is offline   Reply With Quote
Old 09-07-2005, 05:59 PM   #5
Tech Rookie
 
Join Date: Sep 2005
Posts: 4
Default

just got to take clutch apart and check it . no problems there change the glow plug check for the head to be lose .i retuned the car for an hour trying to get top end performance . just nothing there im at a loss. like theres a throtle stop on this car. it probley something stupid im over looking. need help please

thx
john
chev1 is offline   Reply With Quote
Old 09-08-2005, 04:38 AM   #6
Tech Adept
 
Join Date: May 2005
Location: Wilnis, The Netherlands
Posts: 153
Send a message via MSN to Qlone
Thumbs up

Maybe there IS a throttle stop on your car . Take off the air filter and see if your carb opens up completely when you open up the throttle. Don't do this with the engine running!

If it does not open up completely, use the endpoint adjustment on your transmitter to adjust this.
Qlone is offline   Reply With Quote
Old 09-02-2008, 04:48 AM   #7
Tech Rookie
 
Join Date: Aug 2008
Posts: 17
Default

I hav ethe same issue with mine. I can't get the power from the engine to the transmissinon. I'm going to try new clutch shoes and hopefully that fixes the problem. Good Luck!
dub_set is offline   Reply With Quote
Old 09-02-2008, 04:59 AM   #8
Tech Elite
 
Join Date: Sep 2005
Location: Corona Ca.
Posts: 2,834
Trader Rating: 18 (100%+)
Default HPI RS4

Dont over look the flywheel being loose.
Make sure the flywheel nut is tight.
Otherwise, all of the power is being lost with the flywheel spinning, not getting the power to the clutch
__________________
[COLOR="Red"][FONT="Comic Sans MS"][/FONT][/COLOR]BRC358http://www.kamikazercracing.com
nearest barstool
brc358 is offline   Reply With Quote
Old 09-02-2008, 06:33 PM   #9
Tech Fanatic
 
NiTrO BoOsTeR's Avatar
 
Join Date: Dec 2007
Location: Toowoomba
Posts: 947
Trader Rating: 7 (100%+)
Default

ditch the A3 plug and go for a number 8, make sure the carb is opening all the way, check for air leaks, make sure the clutch isnt slipping, also is it changing into second if it has a 2 speed if not then buy the 2 speed upgrade

Mitchell
__________________
Serpent 733 - RB T10rc - Ko Helios EX-10
Serpent 733 - Novarossi 3SCT Tuned
============== SERPENT the only way ============
==== Pro Buggy Rc, Pitsworth - for all my RC needs =====
NiTrO BoOsTeR is offline   Reply With Quote
Old 09-03-2008, 10:13 PM   #10
Tech Rookie
 
Join Date: Aug 2008
Posts: 17
Default

My engine is not shifting but it is a two speed It idles good but when you punch the throttle or ease into try to get speed it starts to bog before you get 10ft. i tried the flywheel but it was tight and i tried a set of slutch shoes from my other engine and same thing. Could this be that i have the needles and idle screw all mest up to give a false good idle when the high speed needle is set to low? HSN is 3 turns out.

Thanks for the help guys
dub_set is offline   Reply With Quote
Old 09-03-2008, 11:56 PM   #11
Tech Fanatic
 
NiTrO BoOsTeR's Avatar
 
Join Date: Dec 2007
Location: Toowoomba
Posts: 947
Trader Rating: 7 (100%+)
Default

mabey be a stupid question but have u touched the needles, it sounds like u havent tuned it,

how to tune
Low end
count to 10 sec
Hit the throttle
if there is no bogging or lagging then no need to lean it
pinch the fuel line if it is about to die at the count of 3 sec then its perfect
if not the lean it out untill it reaches this stage

High end
count to 15
Hit the Throttle
it sould make 3 noises 1 reving 2 changing and 3 a change in the reving (high pitch)
if doesnt
lean untill it does

with ur 2speed clutch u need to adjust it so it engauges so adjust it accordingly
__________________
Serpent 733 - RB T10rc - Ko Helios EX-10
Serpent 733 - Novarossi 3SCT Tuned
============== SERPENT the only way ============
==== Pro Buggy Rc, Pitsworth - for all my RC needs =====
NiTrO BoOsTeR is offline   Reply With Quote
Old 09-04-2008, 12:51 AM   #12
Tech Rookie
 
Join Date: Aug 2008
Posts: 17
Default

I think i'm going to try this i found it in another thread. Good tuning guide.
I think i have problem number 3(at bottom of the post), on the lean end cause of the false idle.

So yes you are right I think my tuning is off but i was confused cause my idle was good. I'll let you know how it works. Thanks alot

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]
dub_set is offline   Reply With Quote
Old 09-04-2008, 02:56 AM   #13
Tech Fanatic
 
NiTrO BoOsTeR's Avatar
 
Join Date: Dec 2007
Location: Toowoomba
Posts: 947
Trader Rating: 7 (100%+)
Default

HMM i think that is a pile of rubbish. i have been taught how to tune a proper engine. the way i told u is best way to get the best out of ur engine.

with it does it sort of rev-cut out - rev - cut out or it sort of roaring like reaving very slow.
__________________
Serpent 733 - RB T10rc - Ko Helios EX-10
Serpent 733 - Novarossi 3SCT Tuned
============== SERPENT the only way ============
==== Pro Buggy Rc, Pitsworth - for all my RC needs =====
NiTrO BoOsTeR is offline   Reply With Quote
Old 09-04-2008, 04:14 AM   #14
Tech Rookie
 
Join Date: Aug 2008
Posts: 17
Default

Alright i'll try your way first! I found that it said Ron Paris' guide to tuning but i don't even know who that is so i'll try what you said.

It's a roaring like reaving really slow
dub_set is offline   Reply With Quote
Old 09-04-2008, 10:57 PM   #15
Tech Rookie
 
Join Date: Aug 2008
Posts: 17
Default

Hey I got it fixed it was about a full turn rich but thats better than lean.LOL
Thanks for all the help. good tips.
dub_set is offline   Reply With Quote
Reply

Similar Threads
Thread Thread Starter Forum Replies Last Post
ESC PROBLEM ghj1997 Electric Off-Road 13 06-04-2008 08:38 AM
Problem RaceANissan616 Nitro On-Road 20 07-23-2006 09:07 PM
KO PRO PO VSF-1 PROBLEM mazmo Australian Racing 4 07-24-2005 07:38 AM
New to R/C and I have a bit of a problem ZeeBMaN Rookie Zone 6 05-15-2003 05:08 AM



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 02:50 PM.


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