Front end feel and confidence- How far can you push?

[Little Mick]

don't mind me but you jacked the back up? that is going to turn it in even faster giving less feel, ie - it will drop into the turns- possibly folding. From what I read above, and Marshy's suggestion that the front forks are typically too low, the raising of the rear will only exacerbate the situation. if anything raise the front trees (lower the forks)

What exactly is it doing? this needs to be understood prior to making changes... If it is tipping in too quick and we are looking to ride height to change the response, then either lowering the rear ( reduced preload or direct lowering will get similar but different results here) may be an option, while raising the front will have a direct impact( several times more than the rear due to distance ratios).

If it is just a lack of feel, then raising the rear won't fix that. I would suggest raising the front until you feel it is more of a push ( or at least having to work harder) so that geometry is close (running setups from Marshy or Kris will get you close) then play with suspension setup.

Feel also comes from suspension settings - where in the turn is it doing what? turning in fast but runs wide? turns in fast and you have to readjust as it goes too tight? struggle to turn it in?
All of these are settings adjustments (possibly valving as well) that can be looked at...



If it is just a very different experience to what you are used to, then more track time on the new ride will help. If it feels fine and not giving you any issues then that's a good starting point. a minor tweak here and there may give an indication of what it is or isn't about to do.

Just remember to make changes based on a plan and sound reasoning.... Otherwise it could get a little messy..

[Marshy]

Little Mick is right, too. Sorry not to acknowledge you Mick.

The issue with making the bike more 'nose down' (as you have done) is you shorten the trail too much. It will tip into corners very quickly (too quickly) but as you get to maximum lean angle and weight through the suspension, the forks get too upright (ie the angle between the forks and the ground, in simple terms, is too steep and the bike 'trips over' the front wheel). Think of riding a pushbike really slowly.... you know when you turn the bars too much at very slow speed and suddenly the front wheel shoots out backwards instead of the bike continuing forwards? That's running out of trail! The point of pressure of the front wheel moves from in front of the forks to behind the forks, and it trips over itself). The motorbike is the same, and that point in the middle of the turn where it suddenly feels unstable and out of grip is when this happens.

So, flatten out the geometry. The bike will tip in more slowly (and you won't feel like it's running up onto the ripple strip on the inside of the turn), and it will have much more mid-corner grip. It'll be more stable throughout, and you'll go faster. It won't feel as 'nimble' but this is a furphy anyway, because you are sacrificing grip and stability for something that only feels racier but isn't.

[Kris]

don't mind me but you jacked the back up? that is going to turn it in even faster giving less feel, ie - it will drop into the turns- possibly folding. From what I read above, and Marshy's suggestion that the front forks are typically too low, the raising of the rear will only exacerbate the situation. if anything raise the front trees (lower the forks)

What exactly is it doing? this needs to be understood prior to making changes... If it is tipping in too quick and we are looking to ride height to change the response, then either lowering the rear ( reduced preload or direct lowering will get similar but different results here) may be an option, while raising the front will have a direct impact( several times more than the rear due to distance ratios).

If it is just a lack of feel, then raising the rear won't fix that. I would suggest raising the front until you feel it is more of a push ( or at least having to work harder) so that geometry is close (running setups from Marshy or Kris will get you close) then play with suspension setup.

Feel also comes from suspension settings - where in the turn is it doing what? turning in fast but runs wide? turns in fast and you have to readjust as it goes too tight? struggle to turn it in?
All of these are settings adjustments (possibly valving as well) that can be looked at...



If it is just a very different experience to what you are used to, then more track time on the new ride will help. If it feels fine and not giving you any issues then that's a good starting point. a minor tweak here and there may give an indication of what it is or isn't about to do.

Just remember to make changes based on a plan and sound reasoning.... Otherwise it could get a little messy..

Think his complaint Mick was the bike runs wide off the turn.

This is an anti squat issue in the rear - as a suggestion and a easy way to prove my theory - put the biggest possible sprocket on your bike at the rear and see if the issue disappears! Easier than changing the shock length. Alternatively, crank up the preload HEAPS - this is going to make the bike incredibly harsh as the spring will be pushed beyond its compliance level but it will raise the rear of the motorcycle essentially achieving the same thing as increasing the shock length.
Before you increase the preload, take a measurement of your axle centre point to somewhere on the bike. Increase the preload, say 5 turns, take another measurement and see if its longer -it will be. This is not a dangerous thing to do.

Few things to look at, having spent alot of time with these bikes at Computrack and having measured a 12 Factory, 13 R and my 13 WSBK bike (Which has a shock length of 343mm)

These are the bits to look at in relation to running wide:

- Gearing
- Swingarm to pivot length (wheelbase)
- Chain pull angle
- Shock length

9-14 models still use a 30mm offset, even with SLIGHTLY different steering head bushes the change is so minute (throw the figures into the online trail calcs - https://www.rbracing-rsr.com/rakeandtrail.html ) and change the triple clamp offset between 09/14 bikes.

If you raise the rear of the bike, there is going to be more anti squat - which is exactly what you need to fix the issue. Yes, this makes slight changes to the trail, but if you keep it in spec at 105-106mm youll still get a stable and easy to steer bike.

Some reading:

http://www.insidemotorcycles.com/blo...nti-squat.html
http://www.sportrider.com/more-fun-geometry
http://www.suspact.com/Anti_Squat.html
http://www.peterverdone.com/archive/rideheight.htm

Last but not least, Aprilia Racings WSS base line settings (tested to great effect by a few guys I talk to in Europe)

http://www.apriliaforum.com/forums/s...previous-years, post number 12

This is for the 15 model, but youll see the shock length

[WRCPUG]

don't mind me but you jacked the back up? that is going to turn it in even faster giving less feel, ie - it will drop into the turns- possibly folding. From what I read above, and Marshy's suggestion that the front forks are typically too low, the raising of the rear will only exacerbate the situation. if anything raise the front trees (lower the forks)

What exactly is it doing? this needs to be understood prior to making changes... If it is tipping in too quick and we are looking to ride height to change the response, then either lowering the rear ( reduced preload or direct lowering will get similar but different results here) may be an option, while raising the front will have a direct impact( several times more than the rear due to distance ratios).

If it is just a lack of feel, then raising the rear won't fix that. I would suggest raising the front until you feel it is more of a push ( or at least having to work harder) so that geometry is close (running setups from Marshy or Kris will get you close) then play with suspension setup.

Feel also comes from suspension settings - where in the turn is it doing what? turning in fast but runs wide? turns in fast and you have to readjust as it goes too tight? struggle to turn it in?
All of these are settings adjustments (possibly valving as well) that can be looked at...

If it is just a very different experience to what you are used to, then more track time on the new ride will help. If it feels fine and not giving you any issues then that's a good starting point. a minor tweak here and there may give an indication of what it is or isn't about to do.

Just remember to make changes based on a plan and sound reasoning.... Otherwise it could get a little messy..

Thanks heaps for the information and tips mate. The thing is this post was not meant to be about any issues i've got with the bike these are just thoughts and questions i've just got about cornering in general.

The only reason i have raised the rear is going by a post on another forum about shock setup and also going by the manual for my bike it suggests for track use to take the rear shock height to 313mm rathe than the 310 for street.

The front end feel on this bike is great and the only issue i did have was a slight running wide on corner exit which i think was caused by too much squat.

But as you mentioned track time is what i need before i make major adjustments and i was at Phillip island last friday and was feeling much more confident. Im almost back down to my PB on my old bike so i came away quite happy.

[Little Mick]

Thanks heaps for the information and tips mate. The thing is this post was not meant to be about any issues i've got with the bike these are just thoughts and questions i've just got about cornering in general.

The only reason i have raised the rear is going by a post on another forum about shock setup and also going by the manual for my bike it suggests for track use to take the rear shock height to 313mm rathe than the 310 for street.

The front end feel on this bike is great and the only issue i did have was a slight running wide on corner exit which i think was caused by too much squat.

But as you mentioned track time is what i need before i make major adjustments and i was at Phillip island last friday and was feeling much more confident. Im almost back down to my PB on my old bike so i came away quite happy.

All good mate.

Getting the Pros to assist you when at the track will help heaps if you can swing it... the point is to make a mental note as you feel it happening so you can go back and assess why and what needs to change.

Pick 2 corners at opposite ends of the track to work on getting the feel. Start with your favourites so you have some lines sorted and are focussing on less variables.

When you come in from the session, take a few minutes to yourself to clearly remember what was going on so you can tell the pro what it was doing. Don't try to analyse it out on track.. Use that time for the next turn

Most of all - Enjoy