Receiver and servos for Nitro

[Citrix]

Hi y'all. In process of building a 1/8th scale nitro car and the manual calls for a receiver that is 43-48mm length by 29-32mm width. It is extremely hard finding a receiver that matches that spec. Is it a problem if I use a receiver that is 32.5mm length by 21.5mm width, or even 40mm length by 20mm width? How would the install and/or mounting be changed because of the size?

 

[alfredwong2003]

I don't believe receiver size matter as long as it fit inside the radio box.

 

[WickedFog]

I have never seen a minimum receiver size called out. That is just silly. As long as it fits in the space available, you are golden.

 

[Citrix]

Does that same principal apply to servos (I.e. as long as it fits in the space its fine, no minimum requirement)

Side question as well, I found a servo that fits by length and width dimensions but not by height. Why would a height dimension matter?

 

[WickedFog]

Servos are generally labeled as standard size, mini, and micro. Heights will vary more than anything, but all the dimensions will vary in each size servo. There are also what are called low profile servos. The best thing to do is look at the servo specs. The torque and speed are important, depending on your kit. Bigger vehicles require more torque. What vehicle are you working on?

 

[Tunedfrog]

If it fits and if it binds, then size makes no difference. But of course, that's been mentioned...

 

[Citrix]

Servos are generally labeled as standard size, mini, and micro. Heights will vary more than anything, but all the dimensions will vary in each size servo. There are also what are called low profile servos. The best thing to do is look at the servo specs. The torque and speed are important, depending on your kit. Bigger vehicles require more torque. What vehicle are you working on?

Kyosho Inferno GT3 1/8th on road kit, the kit calls for 38-41mm by 18-20mm by 31-36mm

 

[Tunedfrog]

Any receiver you buy is going to fit in that receiver box.

 

[Citrix]

Any receiver you buy is going to fit in that receiver box.

What about servo? I'm having a hard time finding a good and fast servo that is low profile enough to fit in sub 36mm for height, most of the ones I'm finding are around 38-39mm in height

 

[WickedFog]

I am going to assume that about any standard servo is going to fit there, based on past Kyosho kits I have assembled. That being said, what is your budget for a servo? Because they can vary in price and quality from $40-$200+.

Do you have calipers? If so, can you measure the servo that came out of it? Then measure the area the servo sits to see exactly what will fit?

If it were me, I would probably buy this bad boy and make it fit if it doesn't (though I suspect it will fit just fine)...
https://www.amainhobbies.com/savox-...shless-steel-gear-servo-sav-sb-2292sg/p536891

 

[Citrix]

I am going to assume that about any standard servo is going to fit there, based on past Kyosho kits I have assembled. That being said, what is your budget for a servo? Because they can vary in price and quality from $40-$200+.

Do you have calipers? If so, can you measure the servo that came out of it? Then measure the area the servo sits to see exactly what will fit?

If it were me, I would probably buy this bad boy and make it fit if it doesn't (though I suspect it will fit just fine)...
https://www.amainhobbies.com/savox-...shless-steel-gear-servo-sav-sb-2292sg/p536891

The one you sent me is a bit more expensive than I would like considering I have to buy 2 (throttle and steering) I would ideally want to spend less than 150 for both. I don't have the actual kit so I can't measure as I'm trying to get everything all researched and finalized before pulling the trigger so it all comes around the same time so I can build all of it. The one you sent me is 2.7mm bigger than kyoshos website states is going to fit. I can always make it fit but I would rather not have to make my own adjustments including having to trim back the top of the servo bracket.

Can you recommend a bit of a cheaper one for throttle and one for steering for me to look into as well? I really appreciate it, Thank you!

 

[WickedFog]

You can search around. Just look for something with around 200+ oz/in of torque for the steering, and 125 oz/in for the throttle. And I would try to stay around .10 sec @ 7.4v or less for speed on both. Are you buying a kit version? I didn't even know they had a kit version of that.

Any standard size servo should fit just fine. I really wouldn't trust those numbers. But I could be wrong.

Good brands in your price range are HiTec, Savox, Reedy

You might look at this one
https://www.amainhobbies.com/hitec-...-digital-servo-high-voltage-hrc35565s/p223431

 

[Greywolf74]

THIS one will work for your steering servo.

THIS one will work for your throttle servo if you can get away with a 37mm height. If the throttle servo also has to be sub 36mm in height then youd need something more like THIS. (NOTE: That last one is only a 6V servo. The other 2 can run on 6V but are more optimal on 7.4V)

 

[alfredwong2003]

You can always shim your servo to make it fit if it is only a couple of mm different. But beware not to use a servo that is too high torque for the throttle. If it is not set up correctly, it could push your engine out a bit and can cause some strip gears. So EPA is very important for high torque servo.

 

[tudordewolf]

I'm having a hard time finding a good and fast servo that is low profile enough to fit in sub 36mm for height, most of the ones I'm finding are around 38-39mm in height

I have to mention JX Servo 4409 MG's. Under $20 a pop. I've bought a bunch and so far they've been great.

Standard footprint, 28mm tall. Not too power-hungry, and surprisingly strong, but not too strong for throttle use, though it's 100% better to have proper endpoints than to count on low stall torque, also because you'll be wasting battery, and stalled servos in a nitro die faster because of the vibrations increasing wear on the gears, especially if it's got a direct physical connection between the geartrain and the source of the vibration, like a throttle linkage.

Pretty fast, too, at .11s/60deg. I tried the 5508MG's too, which claim .07s/60deg, but those drew too much power and got too hot for my liking. I use them for both throttle and steering in 1/10 onroads. You might want something stronger for 1/8 steering, but these are perfect for throttle.

Both are pictured below, 4409 on the right.