I have a 92 quadracer with mild porting, a pipe and a Keihin 35 air stryker carb, an engine builder told me I should have got a 38mm. He said I would see a ton more top end power, but I read the 35mm is better in the woods. I do half woods and half sand pit racing, does anyone have any experience with Keihin carbs, and be able to tell me if there would be enough of a top end power gain, with little or no loss of bottom end, with the use of a 38mm

 

Generally speaking, a larger carb makes more power at higher RPM ranges. They also tend to use more fuel. A stock quadracer 500 carb is a 38 mm Mikuni flatslide, so maybe you could "borrow" one and see if you like the biggens.

 

I believe most pro woods racers use around a 35mm carb. I checked an old 4-Wheel ATV Action article on woods racers and Barry Hawk was using a 34mm. A 38mm would be great if you were riding desert, dunes, or MX. The main problem with Quadracers though is you can't buy bigger gas tanks like them Hondas. Most of the Honda people I ride with have 38's but 4-4.5 gallon tanks. They suck the gas pretty fast too (most have 310-350 kits as well). I would stick with the 35 but if you can borrow a 38, try that too.