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Carb setup .12 Dynamite engine

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elektrico

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Problem: Kyosho Ultima with .12 dynamite

Hello everyone, thank you in advance for your assistance.

I bought a Kyosho Ultima GP Type R, I know is an old model, I got it with a Dynamite .12 engine, the Chasis has a plastic piece that goes over the engine between the head and the carb.

The problem is that the carb needle hits the plastic piece and at the "closed" position if I look inside the carb it has a 2mm (maybe more) gap, I haven't start the engine untill I am sure, but I suspect this will give me some troubles.

If I disassemble the carb, do you know if I can position the carb needle further from that bar? when fully open it points straight with the air intake.

Thank you all.

kyosho12dynamiteproblem.jpg

kyoshoultima.jpg
 
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You can try taking the nut loose that holds the lever on and see if you can reposition the lever. Internally you can't change it.

I don't know what that plastic piece is you're referring to, but I'd look into trimming it out of the way.
 
Hello, thank you for your reply, here is another photo, where you can see that the plastic bar connects to the transmission case.

egwnig.webp


In the picture you will see that the niddle is touching the plastic piece but the carb is still open over 3 mm, like 1/3 open.

THanks
 
Like Racer says, you can reposition the lever by loosening the nut on the side that holds the throttle lever in place.
It's that black nut on the side of the throttle arm.
It might take you a couple of tries, but loosen the nut, close the carb barrel, set the throttle arm to where you think it needs to be, re-tighten the nut.
Once you loosen the nut, moving the lever won't move the barrel.
Once you got this right, you can then use the idle screw to properly set the idle.
To get everything right, you may (may not) have to tweak the linkage.
 
Thank you everyone.

I would like to share this, for other users with same model (Kyosho Ultima SP Type R).
The plastic piece, first I through it was probably made for the original engine, but when I removed it, even when it looked like nothing changed, It is a very important support for the clutch bell gear and the spur to stay in place, otherwise if I try to "bend" the car they slightly separate, enough to strip the gear on power. Later I tryied putting the piece back in place, and the "flexibility" was gone.

The fix was to loosen the nut and reposition the throttle arm like you suggested (thanks for that).

The problem now is, or may not be a problem (sorry I am newbie). On the idle position the carb has a 1mm gap which is fine after reading the engine's manual, but on full throttle the carb doesn't open completely, it reaches the 70% of the whole intake. I guess this can be limited by the servo, a futaba s3003.

Any ideas??

Thank you
 
Since the throttle moves in an arc your throttle is limited by moving the arm. It would have to continue traveling below horizontal(the apex of the arc) to reach WOT. The linkage can only pull forward but to go below horizontal, the linkage would actually have to start to travel back toward the engine.
 
Since the throttle moves in an arc your throttle is limited by moving the arm. It would have to continue traveling below horizontal(the apex of the arc) to reach WOT. The linkage can only pull forward but to go below horizontal, the linkage would actually have to start to travel back toward the engine.

Right!!!!..... when I moved the arm I caused that.. I will have to adapt an extra arm over the original one to probably compensate that.... Or probably invert the arm all the way down and invert the throttle on my control.

More ideas are welcome.
 
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