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I'm nearing the end of my re-re GT build and noticed the high speed needle assembly on the .15S engine AE released hits the brake cam lever. Is there any reason I can't slightly clock/rotate the carb to clear the lever? I suppose my other option is to raise the engine itself up via shims as that would likely work as well.

While I've got you folks, is it normal for the throttle arm to bend ever so slightly when applying full brake? I'm slowly getting the throttle/brake linkages dialed, and I'm doing my best to prevent too much pressure on that plastic throttle arm while, but try as I might, the pressure from the brake spring bends the arm ever so slightly.

Perhaps not the best kit to start with for a nitro newb, as it's a bit finicky for sure, but we're making progress!

Yes you can rotate the carb so it lines up with the linkage it won't affect it negatively in anyway.

The brake linkage should be pulling the brake lever to engage it not pushing, so it shouldn't deform too much in operation but I'm not sure how much you're seeing.

RogueIV wrote: ↑Wed May 21, 2025 8:07 am Yes you can rotate the carb so it lines up with the linkage it won't affect it negatively in anyway.

The brake linkage should be pulling the brake lever to engage it not pushing, so it shouldn't deform too much in operation but I'm not sure how much you're seeing.

Yes, it is pulling while simultaneously pushing the throttle return spring and forcing the throttle arm to bend (as it's already in the closed/idle position) ever so slightly. I just need to find the sweet spot where the brakes are fully engaged without much over-travel on the servo horn.

Are you able to reduce the servo travel on your controller? For steering, I sometimes need to go down to 70% travel in a direction because the steering stops get reached before full servo travel.

Frankentruck wrote: ↑Wed May 21, 2025 12:38 pm Are you able to reduce the servo travel on your controller? For steering, I sometimes need to go down to 70% travel in a direction because the steering stops get reached before full servo travel.

Yes, I run a 10PX. I was actually surprised how much I had to limit throws on the steering servo, and by extension how little steering I get on the GT, though the ackerman likely helps. With that said, that's what I'm shooting for now: getting the end points set on throttle/brake servo so I get good brake engagement without compressing the throttle return spring too much that it starts over-flexing the throttle arm. As someone new to this, it's hard to gauge how much brake pressure I actually need, but that'll just take some trial/error once (or if!) I get it running.

it also doesn't help that the directions on setting linkages don't match the photos in the re-release manual (spacing on the linkage collars etc.). I've actually been using the RC10GT manual from 2002 and it's significantly better than these re-release manuals.

Edit: How did most run the brakes on the GT? The manual says you want a touch of brakes applied at idle, but did most have it setup to have progressively more braking past the trigger neutral position, or did it mainly get most of the braking done when the throttle was returned to idle? I know these aren't as sophisticated as the biased braking on modern 1/8 nitro buggies, but I'm curious how most set them up back in the day.

Ty89m wrote: ↑Wed May 21, 2025 4:35 pm
Edit: How did most run the brakes on the GT? The manual says you want a touch of brakes applied at idle, but did most have it setup to have progressively more braking past the trigger neutral position, or did it mainly get most of the braking done when the throttle was returned to idle? I know these aren't as sophisticated as the biased braking on modern 1/8 nitro buggies, but I'm curious how most set them up back in the day.

I've almost always run with no brakes applied at idle but also mostly run the MIP 3-N-1 clutch as it was a far better design. I'm not sure what the re-re manual says but with the AE clutch you had to trim the shoes, and possibly run a little brake if the truck would creep too much at idle.

I mainly used "drag brake" for tuning as a slight amount of drag brake helped with turn in rotation.


The way I set up the linkage on the GT is to set it up with the radio on. I set up the brakes first without the throttle connected to varify you get full travel and that the brakes lock at full brake, release at idle, and don't engage/bind at full throttle.

Next I hook up the throttle linkage to the carb with both collars loose. At idle with the carb closed I adjust the outside collar so that it just barely touches the throttle pivot. Next I adjust the collar with the spring so that it has enough tension to close the carb fully at idle.

I then double check that everything works as it should, and if things need adjusting make the necessary adjustments and recheck.

As far as the carb lever bending, move the collar that holds the throttle linkage spring as close to the throttle lever as possible, or use a weaker or shorter spring. Ball point pen springs of different pens work great.

If your throttle isnt snapping back to to idle from any throttle position as well thats also a problem. You also should run a throttle return spring in conjunction. Everything should be pretty smooth and not applying force in a way thats bending the carb throttle arm.
Maybe a picture of the linkage would help? Sometimes fiddling with the throttle arm postion, servo horn position and linkages can make everything work much smoother.