First run
 

Last night was the first run of the traxxas rally 1/10 with monster mamba 5700kv .Went well and the car is quick but suffered with the tyres ballooning really bad.Is the a fix for this without taping the tyres

I would upgrade with 17mm hex adapters and then run some GT8 wheels with belted radials from Sweep EXP 50's are really nice:
Sweep Racing GT8 Tires set, BEST Traction, Last long and Most reliable tires on GT Racing!

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MIP 17mm Hex Adapter Kit, Traxxas Slash 4x4, Rally #10115

You could slow down , lol , but where is the fun in that !
You may have to cut the body to fit the wheels , but like Bill said , 17mm hex and 1/8 wheel/tire .
GRPs are also belted .

I'm assuming the Rally purchased was one that came with the 12T Titan motor in it, and the 5700Kv was an upgrade. Quite a big jump in motors I must say, if that's the case. I could never get the full potential out of my 5700Kv motor unless I was running on smoother surfaces and traction was there. Like seedygreenute said...It is fun trying in an off-road situation though.

If your tires are just ballooning when your RC is "diffing out" , then you should look into thicker diff fluids as well.