Has anyone managed to change the preset rake angle of the 1098/1198 from 24.5 to 23.5 degree ? The 1098R has a steering eccentric that can be altered however the s version has a smaller headstock and the Rake angle is prefixed wondered if anyone had reengineered a solution. The bike is Race only.
it depends on what you are trying to achieve? In a simple answer yes, you can make a parallel sleeve or inserts that makes the rake 24 degrees this was a common mod on the 748 etc models, but it shouldn't be considered in isolation. 23.5 rake is very steep but more importantly has a massive impact on trail reducing an already low number in the case of the 748 etc by 6 mm from 96 to 90. ( given the fact most super bikes these day are around 100.) trail is front end feel. Assuming a front wheel diameter of 599.8mm & Frame Rake of 24.5 Deg and a parallel Triple Clamp, The following common Offsets will provide these 'Trail' dimensions; 27mm offset = 106.933mm trail 28mm offset = 105.91mm trail 30mm offset = 103.63mm trail (DK Triples) 36mm offset = 97.8mm trail (standard OEM) Contrary to what appears to be popular believe, changing the length of fork that protrudes through the top triple clamp, will not have any impact on the actual Trail dimension. Fork protrusion may well have an effect on bike handling due to changing wheelbase and ride height, but it’s not because the Trail dimension changes...... The only way that the Trail dimension can be altered by changing the length of fork protrusion is if the Triple Clamp has additional Rake Angle or eccentric stem etc. With the standard OEM clamps, the length of fork protrusion does not change Trail dimension. Things that change the Trail dimension on a parallel stem Triple Clamp are; Triple clamp Offset Front wheel dia. Frame Rake Angle
It is true that 1098R has the larger headstock diameter however the OEM insert does not have the eccentric adjuster like was fitted on 9*6 and **9 models. I assume this was a cost cutting exercise but it means that an eccentric can be fitted if one buys one, or one could use a fixed eccentric with different geometry.
Also as part of the bigger picture.. what ride height is the rear at? Do you have a ride height tool? What rear rocker you using and shock? The 1098 is very low rear as std to accommodated for the umpalumpas .. raising this would help with what you are trying to achieve.
Have Forsaken triples with flat link fitted modified swing arm to allow bigger tyre and relocate caliper fixing allowing slightly longer possible. Forks usually 1 ring showing depending on what circuit I’m racing at rear height measured from set points I have on the bike. Years ago raced a 996sps with adjustable eccentric when swapped over instantly dropped 1.5 secs a lap worked a treat when passing. And wondered is it possible and what parts /engineering would be required. Piccy of me on way to winning club championship.
you do need a ride height tool, your adjuster looks short and therefor low to me but a tool would tell the story and you can then make measured changes..
Ride height tool is a good shout on me shopping list. Picture of swingarm was taken not long after mods carried out shake down/setting up was next. The above diagram is helpful as it shows the layout and parts that would have to be made or parts from possibly a 996sps that could be used ?? Research required.
