And so it begins ...

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looks awesome man! love seeing the updates!
I try to set my throttle/brake servo neutral at idle position as much as possible. you limit this with endpoints. doing this gives you the most travel in either direction allowing for maximum usability of the servo. also if the linkage tries over-extending it wont rotate to far to start coming back around. (with that linkage not really possible, but for some I've worked on turning to far started coming back around going backwards.)
painting bodies is so much fun, honestly its kind of addicting in itself lol.
Hi @D3MON
Thanks for the message. What I'm struggling with set-up wise is ...
when the horn is set in neutral position .. where should the throttle be set? because the brake doesn't move through as much of a range of motion as the throttle body I'm trying to think about where the thottle should be when the brakes are on bull beans.
I've really enjoyed the build though. I'm already thinking that I might change the toe on the rear. I've got it set at .5 degree toe in and being as i'm not going to be racing for some time I'd thinking I might set everything to 0 / neutral so that I can learn to control the vehicle and then tune as I need.
On the painting front ... do you need to prime the shell or can you just buy some paint and crack on?
The attached would be my ideal paintwork but i've got no clue where to even start! (This is my favourite racing car of all time)
 

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Hi @D3MON
Thanks for the message. What I'm struggling with set-up wise is ...
when the horn is set in neutral position .. where should the throttle be set? because the brake doesn't move through as much of a range of motion as the throttle body I'm trying to think about where the thottle should be when the brakes are on bull beans.
I've really enjoyed the build though. I'm already thinking that I might change the toe on the rear. I've got it set at .5 degree toe in and being as i'm not going to be racing for some time I'd thinking I might set everything to 0 / neutral so that I can learn to control the vehicle and then tune as I need.
On the painting front ... do you need to prime the shell or can you just buy some paint and crack on?
The attached would be my ideal paintwork but i've got no clue where to even start! (This is my favourite racing car of all time)
just to confirm, at neutral position of the servo with the carb at idle, you are getting enough swing from the servo arm to fully open the carb correct?
yes there is shorter range of motion to the breaks, as long as the throttle will open all the way with the servo centered it is ok. the biggest concern is running out of brake swing. breaks will wear down over time (very minutely in the case of RCs) and you dont want to run out of brake application swing. the throttle is going to stay the same travel indefinitely.

Painting: no, not primer needed. biggest thing you have to keep in mind is that you are painting from the inside. which means that whatever is first to be put down will be seen.
do make sure to get correct lexan (polycarbonate) paint as well, personally i prefer Tamiya and Duratrax paints, but faskolor, spazstix (never remember how this is spelled), pactra, are all good from what i hear.
as far as that paint the red streak imo is gonig to be the hardest to achieve, most of the rest is going to be masking work. i would definitely google some techniques for painting just to go into it with as much knowledge as possible.
 
On the servo's ,always turn your system on ,check an make sure that the transmitter trim knobs are centered ,then your servo ,go to
center ,then you install the horns ,after that ,you will do the linkage an set those accordingly ,the springs that go on there are to allow
for tension relief when the pressure is put on in opposite direction ,an you fine tune those points by adjusting the collars with set screws
or turn knuckle!

As far as painting the body ,you can buy those graphic sheets ,but always practice on a piece of scrap lexan or clear plastic first!

Also ,do you really want to paint your own body? there is people out there that does paint bodies!...:cool:

Oh ,your buggy is looking great ,you did an awesome job on the build!....:thumbs-up:
 
Hi all,
It’s been a while for me. Apologies for the delay!
I’m actually finished with the build. Nothing left to attach to the chassis. I finally finished bleeding the shocks and got them fitted last weekend.
I went to bind the radio and receiver only to find that the lipo battery I bought was dead so I had to replace that and it’s now all done. I’ve bound the radio and receiver total and it’s making really weird noises (in my opinion) so I’ve posted another threat to everyone seeing if they are normal noises ... see this thread

https://www.rctalk.com/forum/threads/are-these-servo-noises-normal.126882/

So basically once I’m comfortable I’ll be getting this bad boy running!!
 

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Girls and boys,
Well I’ve just fired up my buggy for the first time.... it scared the sh*t out of me. It went to full beans and screamed at me! So I shut it down ... took some pictures and a little video and ... well I need a little more advice.
Why does it go straight to full chat? What do I need to adjust and in what direction so it’ll just idle nicely?
Cheers all
Here’s the video of the travel of the throttle and brake
https://drive.google.com/file/d/13R4CZoVNBNjNFuXIXEanBeLVFTsGifzq/view?usp=drivesdk
 

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Girls and boys,
Well I’ve just fired up my buggy for the first time.... it scared the sh*t out of me. It went to full beans and screamed at me! So I shut it down ... took some pictures and a little video and ... well I need a little more advice.
Why does it go straight to full chat? What do I need to adjust and in what direction so it’ll just idle nicely?
Cheers all
Here’s the video of the travel of the throttle and brake
https://drive.google.com/file/d/13R4CZoVNBNjNFuXIXEanBeLVFTsGifzq/view?usp=drivesdk
should have been set from factory, but something to look at, what does the idle gap look like?
also seems kind of jerky from idle to half to full, is that your inputs? or is that it doing it?
 
should have been set from factory, but something to look at, what does the idle gap look like?
also seems kind of jerky from idle to half to full, is that your inputs? or is that it doing it?

I guess I’m being a little jerky on the throttle .. I’m more trying to demonstrate the movement of the horn rather than the free flowing movement.
also, the screw above the fuel feed pipe .. that can screw inwards a long way but no so far out (so it’s set open?!?) and then the screw on the throttle is quite a long way in (so it’s set closed)
I assume that throttle is controlling air so maybe it’s not letting loads of air in and then on the fuel pipe is set to let quote a lot of air in?
That’s my assumption anyway ...
 
I guess I’m being a little jerky on the throttle .. I’m more trying to demonstrate the movement of the horn rather than the free flowing movement.
also, the screw above the fuel feed pipe .. that can screw inwards a long way but no so far out (so it’s set open?!?) and then the screw on the throttle is quite a long way in (so it’s set closed)
I assume that throttle is controlling air so maybe it’s not letting loads of air in and then on the fuel pipe is set to let quote a lot of air in?
That’s my assumption anyway ...
That screw above the fuel feed is your HSN, after break in that will be the one you adjust primarily. The one off to the side of the carb, where your throttle slide connects to your linkages is your LSN. This after break in will be adjusted one major time then typically occasionally afterwards.
The tube from exhaust to fuel tank pressurises the tank acting as a fuel pump.
There should be a little screw long ways on the carb slide that will adjust your idle gap. Idle gap is typically between .5mm to 1mm (edge of carb bore to furthest point on the carb slide).
You are correct in how the carb works.
Also tighten is to lean the mixture, loosen is to richen.
 
Also ,check the transmitter throttle trim ,when you turn on the transmitter ,it could be opening the gap too much ,so you
will have to adjust that in while adjusting the gap of the carb.
That idle screw is to keep the barrel at an idle gap as you brake so that the engine don't die as well ,but also ,you are in
a break-in mode right now ,so you will have to keep adjusting things as the engine starts to break in!

So ,dry adjust that idle gap while your transmitter is on ,when you set the gap like Demon said ,make sure that it stays
at that gap when you apply brakes too!...:cool:
 
Hi folks,

Ok so I need to validate my knowledge a little here so I've put together one of my trusty power points. (please click here: Nitro Engine tuning query - Hong Nor Force 21.pptx )

In it I've annotated pictures of my engine with my assumptions / guess work / previous knowledge. Please can you tell me what I've got right and wrong.

Also within the powerpoint on the second slide, are two further links to videos which I took today showing the carb barrel travel when looking down the venturi (again I'm assuming that the passageway is called the venturi having google'd it). One video demonstrating travel of the barrel with a secondary spring, and one without.

I'm not sure what I'm supposed to be looking for … in my mind when I fire up the engine it should idle nicely so to me the barrel should be nearly closed (leaving a ~1mm gap) however the free travel without the additional spring means that the aperture was much more open and this could explain why when I fire it up .. the engine goes mad and revvs right up rather than idling nicely.

If my assumption above is correct then I suspect a spring on the throttle arm isn't long enough and I might have to purchase something longer to essentially re-create the same barrel travel as that with the secondary spring.

I also have a confession to make … all three visible screws I've now adjusted and I can't remember factory setting so I think I'm really going to struggle to get this engine ticking over nicely and considering I've not yet run it in I'm worried I'm going to kill it! (although it is why I chose a cheaper engine to learn on)

Thanks all!
 
Hi folks,

Ok so I need to validate my knowledge a little here so I've put together one of my trusty power points. (please click here: Nitro Engine tuning query - Hong Nor Force 21.pptx )

In it I've annotated pictures of my engine with my assumptions / guess work / previous knowledge. Please can you tell me what I've got right and wrong.

Also within the powerpoint on the second slide, are two further links to videos which I took today showing the carb barrel travel when looking down the venturi (again I'm assuming that the passageway is called the venturi having google'd it). One video demonstrating travel of the barrel with a secondary spring, and one without.

I'm not sure what I'm supposed to be looking for … in my mind when I fire up the engine it should idle nicely so to me the barrel should be nearly closed (leaving a ~1mm gap) however the free travel without the additional spring means that the aperture was much more open and this could explain why when I fire it up .. the engine goes mad and revvs right up rather than idling nicely.

If my assumption above is correct then I suspect a spring on the throttle arm isn't long enough and I might have to purchase something longer to essentially re-create the same barrel travel as that with the secondary spring.

I also have a confession to make … all three visible screws I've now adjusted and I can't remember factory setting so I think I'm really going to struggle to get this engine ticking over nicely and considering I've not yet run it in I'm worried I'm going to kill it! (although it is why I chose a cheaper engine to learn on)

Thanks all!
on your powerpoint, HSN you have correct, tighten is leaning, leaning is reducing amount of fuel/oil mixture from approximately 1/4-(1/2 on some) to full throttle. (if an engine (yours does not) have a mid speed needle, it takes over from between 1/2-3/4 up till full throttle.
it does look like you have the LSN and idle reversed, the brass needle nearest your throttle linkage is the Low Speed Needle (LSN), idle is the little black one on the side of the carb.
Idle needle:
is an adjustment screw that physically limits the closing of the carburetor. makes it so you can't fully close the carb using the transmitter so when you brake it doesn't kill the engine.
tightening= opens the gap
loosening= closes the gap

LSN:
above idle to 1/4 (1/2)
governs mixture at the lower end of throttle.
this will give you your snappiness off the line. if its dogging and spitting a bunch of fuel its to rich. if its cutting out its too lean.

check out this link, has some decent information. there are many tuning approaches and many have different ways to say it, and many look closer into certain aspects than others.
i like this one as it gives examples of what they are talking about.
(sorry its not from RCTalk forum)
https://www.rctech.net/forum/onroad-nitro-engine-zone/295490-tuning-bible.html

did your engine come with a manual? should give some input as to what base settings are. typically it is flush on both LSN and HSN and 1mm of gap on the Idle needle.
 
Hi folks,

Ok so I need to validate my knowledge a little here so I've put together one of my trusty power points. (please click here: Nitro Engine tuning query - Hong Nor Force 21.pptx )

In it I've annotated pictures of my engine with my assumptions / guess work / previous knowledge. Please can you tell me what I've got right and wrong.

Also within the powerpoint on the second slide, are two further links to videos which I took today showing the carb barrel travel when looking down the venturi (again I'm assuming that the passageway is called the venturi having google'd it). One video demonstrating travel of the barrel with a secondary spring, and one without.

I'm not sure what I'm supposed to be looking for … in my mind when I fire up the engine it should idle nicely so to me the barrel should be nearly closed (leaving a ~1mm gap) however the free travel without the additional spring means that the aperture was much more open and this could explain why when I fire it up .. the engine goes mad and revvs right up rather than idling nicely.

If my assumption above is correct then I suspect a spring on the throttle arm isn't long enough and I might have to purchase something longer to essentially re-create the same barrel travel as that with the secondary spring.

I also have a confession to make … all three visible screws I've now adjusted and I can't remember factory setting so I think I'm really going to struggle to get this engine ticking over nicely and considering I've not yet run it in I'm worried I'm going to kill it! (although it is why I chose a cheaper engine to learn on)

Thanks all!
and yes the little rubber sleeve that goes over the carb has a tendency to spring the carb open somewhat, the spring is more of a failsafe to prevent runaways when the RX loses connection, or servo doesn't respond. controller and RX should always be on while you are starting your engine to prevent that (made the mistake when i was learning one too many times lol) make sure that your throttle trim fully closes the carb at idle position, i set mine to go a bit past just closing the carb. some of the springs mount to a point on the block, chassis, or even on the thottle linkage itself. wherever you can mount it to have tension to close the throttle when you lose servo power.
 
Girls and boys,
Merry Christmas to you all. Hope everyone is having a lovely time so far and looking forward to NYE! I’ve had some good garage time recently and got my RC running ... I mean actually running! Engine properly running and I think it’s running ok. I’m going to post a couple of videos shortly when I’ve got links sorted out because I just want to get a few folks in the know to tell me if it all sounds and looks OK. The only thing I wondered about is the colour of the smoke.
anyway in the meantime I really hope everyone is having a lovely Christmas season! I’d also like to extend my sincere thanks to everyone who’s been there to help me this year. I wouldn’t have been able to get this far without you all!!
Thanks guys
Rich
 
Girls and boys,
Merry Christmas to you all. Hope everyone is having a lovely time so far and looking forward to NYE! I’ve had some good garage time recently and got my RC running ... I mean actually running! Engine properly running and I think it’s running ok. I’m going to post a couple of videos shortly when I’ve got links sorted out because I just want to get a few folks in the know to tell me if it all sounds and looks OK. The only thing I wondered about is the colour of the smoke.
anyway in the meantime I really hope everyone is having a lovely Christmas season! I’d also like to extend my sincere thanks to everyone who’s been there to help me this year. I wouldn’t have been able to get this far without you all!!
Thanks guys
Rich

The smoke is not an issue ,a medium to heavy smoke ,just means that it is set on the rich side ,presumaly ,for break-in ,
however ,you may want to leave it on the rich setting for awhile ,but after the break-in ,you should always see a light white
trail of smoke ,that is a good thing!....:thumbs-up:
 
Merry Christmas to you, too. It's ALIVE!!! Sounds just a bit sputtery but not bad. Might be a little high on the idle but that's not a problem now unless it's trying to creep forward. That will cause wear on the clutch. The true test of the tune is when it's running on the street. How the take off is, and how it sounds at WOT. Post that vid and we'll get you tuned in.
 
@Rolex thanks so much for the message - did you manage to check the video? It’s the only one I have at the moment of the beast running. I’ll keep going with it but one of the concerns I had when I gave it a throttle blip the wheels span but came to an abrupt stop so I’m wondering if I’ve not got the brakes set properly?!
 
That's the video I watched before commenting, above. It's just idling and there doesn't seem to be anything stopping it from creeping forward, so the clutch is not engaging. Other than that, there were no throttle blips so I can't tell anything else.
 
Hi all,
Well here’s a little update. The buggy seems to me like it’s running well. I’m still running the engine reasonably rich but breaking in is nearly finished. I’m going to save my final updates with pictures on this thread for when I’ve got the body painted. I’ve got a design chosen so I just need to send it off and get it done (I’m not very good at painting)
Quick question : can you get 8th scale. Replica racing stickers like Mobil1, Gulf etc?
Anyway I am loving my RC. It’s such a great hobby which I find really satisfying.
I am however going to post in the chassis section because I’ve got some setup hiccups to work through just so I can get it running that bit better.
 
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