suspension set-up?

Wheels, shocks, forks, frame
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mgtkr1
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suspension set-up?

Post by mgtkr1 »

im 10 half st. and would like to know if there is anywere on the site that gives a basic start point for suspension settings for race/track use on a kr? atm im stuck with a std rear shock off a kr1 but hope to improve once i learn what to look out for (good/bad setup by feel) with a basic shock. as the class rules are pretty lax i wondered if any one had used internals out one of the 400sp's (rwu forks, same diameter such as fzr rrsp) as these bikes are highly adjustable and mated to kr1/kr1s sliders would be very discreet. will be getting r6 rear shock as the length suits my requirements aswell as been highly adjustable/pretty damn cheap of ebay!! :D cheers matt
rgvsean
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Post by rgvsean »

To be honest if you are serious about good set up then the first thing is to get it serviced to make sure you are not wasting your time. I am sure I have posted this before but no harm in a re-fresh.

a basic guide:


Suspension feels rough
Unsmooth riding=Check suspension sliding parts or Check for front axle off-centre or twisted forks.
Spring load too high=Decrease spring load or Decrease oil or change the spring to one with a lower load.
Bottoming out=Increase spring load or Increase oil or Change spring for one with a higher load.
Damping to much=Decrease damping force.
Tyre too hard=Change tyre or Decrease pressure.

Feels too soft
Damping not enough=Increase damping force.

Under steers
Caster too much=Increase fork rebound damping force or Increase inner tube end protrusion or Decrease front fork preload or Increase rear spring preload or Decrease rear rebound damping force or raise chassis rear end or Increase rear compression damping force.

Chatters (small pitching)
Rattles in steering head pipe=Check tightness of bearing end nut.
Tire or wheel imbalanced=Check the balancing and check for a Buckled wheel.
Tires not matched=Review the tyre choice or lower tire pressure.
Chassis not matched=Counter resonance by changing spring preload or changing damping force.


Kick back (steering shaking)
If occurs when on the power=insufficient fork rebound travel=Decrease spring preload or Increase The front fork top end protrusion and the rear end height.
If occurs when off the power=Insufficient fork compression travel/too much fork compression travel=Decrease or increase front spring preload or change the front springs for one with a lower/higher load figure or Decrease/Increase front fork damping force.
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the-elf
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Post by the-elf »

Matt,

As the rules allow you to change and you want to race it I would chuck the standard stiuff in a bin and start new. USD 400 SP forks are a good idea, mine are ZXR400H SP forks which have also had the internals changed as well and I've got an ohlins rear shock. The standard suspension soon reaches its limits on the track.
-- Lets go Racing
Sponsored by:
Paddockstand Ltd: Tyre and Bike spares http://www.paddockstand.co.uk
mgtkr1
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Post by mgtkr1 »

sean, that was a very helpful and intresting write up, enjoyed reading and learning a bit about suspension set up. elf, i intend to upgrade the forks/shock at some stage as std stuff is poo unless its fresh and tbh, i dont think its worth spending money on having it reworked as the adjustment is limited to preload. i was considering a set of fzr rrsp forks as the od is the same and are highly adjustable. should be fairly light similar to std kr1 forks as there rwu.
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the-elf
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Post by the-elf »

Matt,

With mine the rear has worked very well with very little dialing in needed. The raising of the ride height has improved it no end and as RC46 will verifry she turns in darn quick :D . The rGV swinger has improved the rear as well I have put this down to an increase in stiffness all in all the rear is ace.

The front has taken a bit more work to get dialed in which wasn't helped when some nice git turned one of the compression adjusters fully in :twisted: and left me wondering why my front end wasn't working at all and wasting a lot of track time. I think its now somewhere near and as I'm happy with the RGV swinger I won't be changing the rear again so I just need to get the front dialed in a bit better.

If your at the Cadwell trackday on the 26th you'll welcome to try my bike and see what you think.
-- Lets go Racing
Sponsored by:
Paddockstand Ltd: Tyre and Bike spares http://www.paddockstand.co.uk
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