Figured I’d bring up some of the stuff that has been hitting my desk lately. A chassis designed to use equal length arms to eliminate bump steer will in fact make it easy to eliminate bump steer, but you’re giving up everything that helps you maintain corner grip. On paper, I’m coming up with around a 20% loss in grip on average for the frames I have a model for. Some of them peak around a 40% loss in grip. Bump steer is fine in some circumstances. I like no bump steer for the lower 80% of the travel and then a touch of bump in. This helps keep it straight on hard hits. Everybody talks about straight line bump steer but nobody talks about when the bars are turned, which is a VASTLY more important matter. I’m getting close to trade secrets here but suffice it to say that eliminating bump steer while turning can cost you seconds. Not tenths. Seconds. Give the tire what it wants, not what Instagram hashtags tell you that it should want. A year or two ago, I would have told you everything I know on the matter but after having another chassis builder tell me that I needed to come read this guide (ya know, the one I wrote) and learn a few things, I’m now aware that I’m helping an asshole. I have zero tolerance for rude people so if you want to know more about this, PM me or find me on facebook. People like 250R rake (which is technically called wheel recession angle or WRA) but that comes at a cost. Higher WRA of around 15 degrees or so can cause a lot of dive under braking. Add in the extra weight of something that isn’t a 250R and the issue gets worse. If you can work with it then the extra comfort and compliance can be worth the trade off, but you have to work with it (weight on your feet under braking, not into your hands). There are about 6-7 things to look at with WRA but the gist is that heavier riders need less, heavier braking needs less, and a shorter wheelbase needs less. For the 800th time, no wheel spacers ever. The shock matters more than the arm. With the shock, the spring has one job: to hold the load introduced to it. The valving controls how fast the spring gets back to its steady state when the load changes. If it’s rough as fuck, 95% of your issues are either because your tire pressure is off, your ride height is off, or your valving is off. It is VERY rarely the spring(s). If someone quotes hooke’s law (a sign they don’t know shit) then ask how that changes with velocity. Even if you don’t know the answer, it’ll let them know they’re at the end of their rope. I’ll be back in about a month to bitch about something else. Sent from my iPhone using Tapatalk