Hey, can anyone give me a basic rundown on how changing the offset of your triple clamps affects handling? I think that moving the forks forward will slow down the steering but I don't know if there are any other affects from doing that. I have never messed with that stuff so was hoping that someone here could fill me in.
Forward will reduce trail. Reducing trail will make the bike steer with less effort at the expense of stability and front end feel.
Is there a set of target numbers for trail or is it all test and tune? Does it come down to personal preference? It seems like a fluid number measured from an imaginary plane. A cbr1000rr like mine has a stock trail of 96mm, per wikipedia, vs a stock zx10r with 107mm. These are the two ends of the spectrum for stock liter bikes, and the difference is less than a half inch. Lets say you raise the forks or change the rear height, all of a sudden you are tweaking trail by altering the rake of the bike. What about different tire sizes or spring rates, or a full tank of gas changing the dynamic geometry of the bike? Even looking at adjustable offset triple clamps, the most they vary from stock is usually +/- 3mm. But then you do change the rake angle, minimally, by pushing the forks out or in, just as a function of changing the distance between the neck and the axle, so maybe its +/- 3.0x mm of effective offset. So, I guess what I am saying is trail is affected by many different factors. Has anyone ever switched to an adjustable offset triple, changed the offset a few mm while leaving everything else the same and thought, wow, this feels markedly different? Or does the ability to adjust trail just mix into the other adjustments you can make?
Yes. I can feel each 1mm change. 2mm offset is an undeniable change. bike is 11 gsxr750 with IMA triples.
Going fast requires good corner entry speed. To enter with speed you need confidence. Confidence comes from being comfortable on the bike and being able to feel whats happening. Trail is regarded as the most important number of a bikes setup and will have noticeable effects between adjustments. In simple terms, more trail means more stability and front end feel and the easiest most direct way to adjust this is with adjustable triples. 1mm offset change directly translates to 1mm of trail change. The downside to more trail is harder steering. Trail is affected by or can be changed with ride height but you need to adjust the forks 4mm up or down the triple to equal 1mm of trail. Trying to adjust trail this was will usually upset the rest of the bike. So to isolate trail adjustable triples were invented. For Example Ducatis have always been a bike where lower offset triples were a must. Stock offset is 36mm on many Ducati superbikes. When people would set these bikes up for racing, many would change to 30mm offset or lower all the way to 25mm offset. Thats up to 11mm difference in trail which is HUGE!! When tuning or adjusting setup, try to move in 2mm increments. Generally super bikes have trail numbers around 95mm up to around 110mm. There is no magic setting and different tracks, conditions, and riders all need different setup. Dont be afraid to change your setup to test and see what each extreme of setup feels like.
generally speaking, more offset (just offset, moving the forks out from the steering stem..not changing rake) makes it steer faster, but, less high speed stability. Less offset, forks are a hair closer to the steering stem, gives more high speed stability. Don't get this confused with "wheelbase", moving the axle backward. This is NOT the same thing. I'm also not talking about changing the rake of the forks with clamps that would do this. that's another way to change stuff. lots of good info in posts above mine for sure.
