FOR ALL YOU RC RACERS OUT THERE:
ROAR Racing recently announced a change to the maximum height rule for 2S saddle Pack Batteries. The 2008 ROAR rules originally permitted saddle pack batteries with a maximum height of 32mm based on the batteries available at the time. They then changed the rule in late 2009 to a maximum of 25.1mm to make them consistent with the majority of battery packs available on the market.
The reason you’ve still seen people using batteries in excess of 25.1mm is because the batteries were grandfathered for a period of one year to allow drivers to use packs already purchased under the original rule. The one year period expired in late 2010, so batteries legal for ROAR competition for the 2011 season and beyond will need to be in compliance with the existing rule. The battery packs in question will be removed from the approved list.
Now, from what I understand, the reason for following through with change in the rule is ALL (as in EVERY CAR AVAILABLE) is made for batteries using the 25.1mm height. The cars have to be modified to accept the older, taller battery packs, and there are very few on the market. Manufacturers need to know what common size of battery they can base their design on. It makes far more sense to have batteries that are the same size and let the manufacturer build whatever capacity is possible.
Now, if you don’t know what I’m really talking about, RC drivers in competitions have the choice of running either a single LiPo battery or two (dual) LiPo batteries in a saddle pack configuration. Choosing a saddle pack configuration can help drivers gain an edge on the competition. The use of saddle packs allows you to lower the elevation of the total weight/mass of the heaviest component on the vehicle (the battery) by 50%. A typical ROAR Approved 4s 5000mah LiPo battery weighs approx. 580g to 600g, so that means a whopping 300g approx. can be sliced off the top from the highest point and relocated to the lowest possible elevation on the vehicle which is directly against the chassis. There is also measurable improvement to the overall balance of the
vehicle created when the battery weight is spread out in dual battery saddle pack setups.
I’m not an expert on this, just reporting the news but if you have any questions or comments, post them below and I will try to answer! Also, check out our post on Lipo Battery Configuration Info to get a better understanding. Thanks and happy racing!