I had all kinds of problems using my Mamba Max speedo with my R1 with the Spektrum system. I ran both the Pro and regular DSM system and 3 different DSM receivers and also used the React radio setup for DSM mode and had the same problems. Fail safe would kick on all the time no matter what I tried. I used the SPektrum cap, lipo receiver pack with 6.2v regulator and straight 7 volts and still the same problems.
Switched to the 3pk with the synthesized system and no more problems. I know from talking with alot of people sometimes you have problems sometimes your lucky and don't.
Castle Creations (Since 2005)
Bumps & Jumps RC (One of the best racing facilities around)
ST Racing Concepts (STRC) Great aluminum upgrades for many brands.
Custom Works (Best Oval Cars around). Too many titles to list
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