Hello Guys, Haven't been on for a while due to be busy racing and business as well.
I recently ran the Edam Razor at the RCX Expo race in California. This is the second race I have run this car. I am continually finding better ideas to increase the handling of the car all the time. I have been receiving email from all over the world asking about what I am doing. I am pleased as always to answer any questions as I can. What I don't know I will find out for you and get back to you as quickly as possible.
As soon as I can get more Edam Racers here in the United States it will help greatly in obtaining new and better ideas for handling problems.
I will give you some ideas about the lack of front grip on the Razor and how to help cure the problem. This is the most common question.
First part of the solution with the Razor's lack of front grip is the very low RC (roll center) of the rear. Putting in a minimum of 2mm to 3mm of shims under the mounting position of the rear upper A arms and where it mounts to the rear hubs. This will help in raising the RC in the rear. Making sure you have a least 4degrees of caster in the rear will also help. Best way to determine if the caster is correct is by the cone shape of the rear tire wear.
The next step would be to work on your front end to obtain more steering. Here is where the "rule of thumb" sometimes does not always hold. However here is what I did to gain a lot of steering. The RC in the fron was also quite low and in turns the car rolled so much and so deeply it rides on the stops. When a car rolls that deeply you are not using the suspension system as all. The car will then push. I decided to make a major change to the car after talking to someone that has great knowledge in car design and has driven the Razor.
I fabricated the front bulkheads to accept an upper A arm hanger that is designed for the Mugen. Positioned the hanger so the Upper A arms inside pins are position 2mm outside the chassis, 2mm lower that stock. I cut the upper A arm by 2mm. I have a picture attached.
I now have a car that steers quickly and turns excellent in off power, middle off power and out on power. These changes if one would look at it could make the steering go the opposite way since the RC is higher. However it matches very well to the rear and has created a nicely balance car.
At the RCX main I had some problems in the beginning but got the car to third place and held that position until less than two minutes left the one way bearing in first gear went out. This ended my day but it was good to hear the announcer of the race compliment the car on how well it was handling. I am going to try placing the upper A arm pins 1mm lower than stock and see how that works for me as well. I feel right now I may have too much steering. But for racers overseas where your traction is not as high as ours here in the States, this may be an interesting start.
Stephan sent me a step by step "Building Tips" for a new person building his first 1/8th car or first Razor. I will place this on this thread soon.