rear end too light or just me?

[Paulfzs]

im about 11 stone, took the bike out for some fast paced roundabouts and straights near redline in 3rd for most of it with some mates, problem i found which almost put me into the lane divide was when i downshift or rear break a bit hard my back locks up and skips along the floor.


any ideas?


my rear shock appears to be on its hardest setting but its not solid.

[darrsi]

What's the story with the rear shock?
Original, old, upgraded?

[Paulfzs]

as far as im aware original shock.


it doesnt feel super bouncy it doesnt feel massively hard, would making it softer help combat the back skipping as it would compress more

[fazersharp]

So you are in 3rd - red line and downshifting to 2nd and asking why the back is skipping and locking up.

Yes I know Im paraphrasing a little but-------------- well !

[Paulfzs]

So you are in 3rd - red line and downshifting to 2nd and asking why the back is skipping and locking up.

Yes I know Im paraphrasing a little but-------------- well !

not changing down from 3rd to 2nd at redline but its still pretty high rpm

[Yamazer-92]

Put some bricks in your top box, that's what I did. Not a large Hawaiian dominoes though, that never ends well after a Raz.

[fazersharp]

You have of course heard of "blipping" the throttle when clutch is in when down shifting to counter engine braking. Just checking

[darrsi]

Mileage?

[noggythenog]

I dont use my back brake, but surely any bike will lock the rear if there isnt enough weight on it ie under braking....but the 600 back brakes are rubbish anyway....far as ive figured out the back brake is for slow speed maneouvering or for initially loading up the front end aint it?

[kebab19]

It sounds like the damping on your shock might be on the way out, what sorta mileage has it done?
Failing that, the max preload setting might not be a good match for your weight

[Punkstig]

/\ someone's phishing for business, spare R6 shock by chance?

I kid of course!

[Yamazer-92]

On a serious note, I weigh about 12.5 stone in my riding gear and was on preload 5 or 6 of 9 on the OEM shock which was correct sag wise, so having it on 9 sounds way too much if you're 11 stone. If your rear wheel is "skipping" I would probably suggest you're down-shifting without blipping the throttle to match the RPM like fazersharp said which will mean the engine braking / drive chain will make the wheel lock. The standard rear brake would have to be applied pretty hard to lock the rear wheel noticably at near redline in 3rd gear speeds unless you had the fronts on very hard as well. Have you checked your swing arm bearings and shock bearings?

[kebab19]

/\ someone's phishing for business, spare R6 shock by chance?

I kid of course!

Hahaaaa love it 
No need, our youngest FZS600's are now 12 years old and with age the rear shocks mature like a fine wine... not

[mtread]

Most 600 original rear shocks are knackered after 20K miles, but then they tend to go soft rather than hard (oo-er) and bounce around or sag. Perhaps it's seizing. What's it like just sitting on it and bouncing up and down ?

[Paulfzs]

if its original itll be 44,000 miles.


the locking up isnt a problem i can live with the back end sliding its the skipping i cant deal with because i have no control over the bike at all, it locks up and the rear wheel bounces.


ill get on it tomorrow and slacken off the shock, ive spent too much on this to change the shock at the moment.

[fazersharp]

So do you actually use the "blip" technique as you did not say, if not then give it a go

[darrsi]

I'd guess you're just in the wrong gear at too high revs that's causing the locking up.


And your shock should be well and truly knackered by now i'd imagine!

[midden]

slacken the preload by a few steps, you'll notice the difference

[slimwilly]

Get a far girlfriend

[darrsi]

Get a far girlfriend

Typo's can really spoil a joke. 

[Paulfzs]

ive tried blipping the throttle a few times seems to make it better, i do have a gf but she is close so ill have to find a far one.

[His Dudeness]

Every bike will try and lock the back wheel if you change down at too high revs or hit the back brake too hard. That's why there's slipper clutches and abs! The shock might be tired but I don't think it is causing your problem

wiki on slipper clutches
They are designed to partially disengage or "slip" when the rear wheel tries to drive the engine faster than it would run under its own power. The engine braking forces in conventional clutches will normally be transmitted back along the drive chain causing the rear wheel to hop, chatter or lose traction. This is especially noted on larger displacement four-stroke engines, which have greater engine braking than their two-stroke or smaller displacement counterparts. Slipper clutches eliminate this extra loading on the rear suspension giving riders a more predictable ride and minimize the risk of over-revving the engine during downshifts. Slipper clutches can also prevent a catastrophic rear wheel lockup in case of engine seizure. Generally, the amount of force needed to disengage the clutch is adjustable to suit the application

[Nightfury]

The default setting for preload on the rear shock is position 4. Having it cranked up to 9 riding solo is just asking for trouble. It is the movement of the suspension that keeps thy tyre in contact with the road.

[Hedgetrimmer]

I don't think this is purely a preload problem. At 44k miles, the shock has probably had it's day. You probably feel you need the preload that high to compensate for the fact the shock is tired. If you can't afford to replace it, then you should ride to the bike's current capabilities, which means, ease off a bit with the ragging.

Why are you changing down near the redline?
Why are you using the rear brake on corner entry?

Come off throttle on corner entry, using front brake only. If you don't feel they are up to the job, ride accordingly. As said above, blip the throttle on down changes. Match the revs to the gear you are in properly, i.e., don't down shift when near the redline.

[midden]

my rear shock appears to be on its hardest setting but its not solid.

I get the impression the pre load  was at this setting when you bought the bike. Am I correct Paul. 
If so,  there's no point speculating on knackered shocks, hard downshifts and braking untill you return the pre load back to the default setting and take it for a ride.   Just my opinion, again