Ok guys i'm a bit confused about custom swing arm land A-arm lengths for differant types of applications. I have a 250r that I would like to set up for MX racing. I'm confused about what size swing arm to get b/c i want to buy a lighter weight chromoly swing arm and A-arms. Should I extend the rear swing arm or keep it stock length?
If i should extend it how long should i go? I was thinking about a +1" to 2" length, As far as A-arms I was going to go with +2" -1" off set. Would this sound right? I want to know what are some proven sizes that i could use to make my quad handle better, be more stable/balanced, and size swing to get more traction to the ground.

All of this is a little over my head. When I had my Banshee set up for the dunes I had a 10" swing and 4" long travel A-arms. Since in MX i'm not going in a WOT str8 line, I was concerned about suspension sizes and how handling would be affected.

The simple rules of thumbs i was told was for dunes was "go long and go wide", for MX "keep it short". How accurate is this?

I want my 250R set up to run MX but yet still be an all around play bike.

 

What year 250R do you have? IIRC, they usually go +2 +1 on the arms. That would give you a total of 4 extra inches of width and stretches the wheelbase 1" as well. The 88/89R had a slightly longer swingarm stock to help alleviate the 86/87's tendency to spin out. If you have an 88 or 89 model then +1 should be fine. I would ask the maker of the components you are planning to install though. They have the best knowledge of what works well on the 250R.

 

thanks Scooter. My 250r is a 86 model. I was gonna go +2 inch on the swing over factory. When i go with the +2+1 A-arms could I use my stock tie rods or will they be too short.

 

You will need new tie rods for +2 for sure. Usually the arms come as a kit with tie rods included.