Perpetuem and muscle cramps

[xcwoodsracer]

I race Hare Scrambles, off road motorcycles, in the rocky New England woods. The races last 2.5 to 3 hours and are non-stop, full out sprints start to finish. No time to rest or stop to take a pill or gel, so all my fluids and fuel have to come from my hydro pack. I have been using Gatorade, but I get major energy crashes between drinking it so I switched to Perpetuem for yesterdays race. It worked fantastic, but I started getting leg cramps on the last lap, which raely happens to me. It was about 92 degrees out and 90% humidity. I wear about 25 pounds of protective gear, which does not allow great ventilation so I sweat a lot. I typically drink 3 liters of fluids during the race. With the Perpetuem I mixed 4 scoops to 3 liters and only drank about 75% of the bladder. I did take 2 endurolyte capsules 40 minutes before the race, but still cramped. My pre race meal was 2 bananas and a Hammer bar 3 hours prior to the start.
Should I be mixing powdered Endurolyte into my hydrator with the Perpetuem? Will it make the café latte flavor unpalatable?
Any suggestions?