How and why

[Str8 Jacket]

causin chatter at the rear?

I heard that was his problem too.... I reckon he should check his suspension.

[fi5hy]

Hey just a passin thought.. you were talkin bout chatter etc. could the problem be your front end setup causin chatter at the rear?

No the front was ok at the start to about mid race then the back tyre was balling up so much that in the end it felt like cornering with a knobbly. The vibes though the bike on full lean was incredible. know I now what the motogp boys are on about

[saxet]

Ok what about tyre balancing? It still could be compression or rebound damping not at the optimum causing an oscillation when cornering or due to small slides setting up the vibes.

[fi5hy]

balancing yes could check that as for rebound and damping it hasn't got ether

[saxet]

I was thinking maybe you have an issue with the front damping that could be showing up at the rear wheel. Never happend to me but I've read about it.

[fi5hy]

good point

[Sully60]

I think the tyre has to do more work, this only started happening with the race attacks and slicks on the 17's right?
Crank up that rear preload brother!

Or just slow down a little!

[F5 Dave]

odd thing is preload is apparently low & there is like no static sag. I thought it was just because the preload was too high or something is siezed, but new bearings & another shock. It is quite odd. Have you checked to see if it is bottoming out when cranked down? Seems like heaps of room but. . .

Still seems odd that there is no sag whatsoever. even my 50 can be adjusted to have some static sag & the back end is really light. The 17" tyres keep doing it, so why? Is the change the cause for some reason or just a red herring & you haven't had as sticky tires. nah 3 diff tires. If that rim is severely out of balance or round you should be able to see it pretty quickly.

[TZ350]

For what its worth:-

The very fast guys at Mt Wellington run 18 psi F & R in their slicks. Any more and they don't get up to a good working temperature.

There is a temperature where slicks work best, about 55 degrees C and when they are working well they feel a little sticky to the touch (from the oils in the rubber which makes the rubber complient). If they are over inflated or cold they can get the shreaded look but arent so sticky to the touch.

Fi5hy corners as hard as an RS but his all up weight bike+rider is much more, overloading cold tyres? and just ripping the rubber could that be possible?.

Just another idea for the jigsaw.

.

[richban]

For what its worth:-

The very fast guys at Mt Wellington run 18 psi F & R in their slicks. Any more and they don't get up to a good working temperature.

There is a temperature where slicks work best, about 55 degrees C and when they are working well they feel a little sticky to the touch (from the oils in the rubber which makes the rubber complient). If they are over inflated or cold they can get the shreaded look but arent so sticky to the touch.

Fi5hy corners as hard as an RS but his all up weight bike+rider is much more, overloading cold tyres? and just ripping the rubber could that be possible?.

Just another idea for the jigsaw.

.

Anyone got access to some tyre warmers that might help figure it out.

[fi5hy]

odd thing is preload is apparently low & there is like no static sag. I thought it was just because the preload was too high or something is siezed, but new bearings & another shock. It is quite odd. Have you checked to see if it is bottoming out when cranked down? Seems like heaps of room but. . .

.

Checked that I had a tie down on it and wound it right down all ok there

[fi5hy]

I think the tyre has to do more work, this only started happening with the race attacks and slicks on the 17's right?
Crank up that rear preload brother!

Or just slow down a little!

Cranked up the preload to 5

[fi5hy]

For what its worth:-

The very fast guys at Mt Wellington run 18 psi F & R in their slicks. Any more and they don't get up to a good working temperature.

There is a temperature where slicks work best, about 55 degrees C and when they are working well they feel a little sticky to the touch (from the oils in the rubber which makes the rubber complient). If they are over inflated or cold they can get the shreaded look but arent so sticky to the touch.

Fi5hy corners as hard as an RS but his all up weight bike+rider is much more, overloading cold tyres? and just ripping the rubber could that be possible?.

Just another idea for the jigsaw.

.

Someone Else said the same thing about 15 to 18 psi I have one more 120/17 left to try. I might try it at that psi and see. I have got someone trying to track down a shock with a bit more adjustment.

Thanks for the input

[TZ350]

Kiatoke is mostly R Hand corners. If you have a tyre thats cooked on one side, (I know its not the done thing) but for the sake of economy could you turn it around and experiment with whats left of the good side.

Start at say 22psi cold do a few laps, feel the tyre, lower the (now hot) pressure a psi or two, no need to measure it, just let out a puff. Do a few more laps, feel the tyre Etc. Etc. down and down slowly.

The tyre should go from cold dry and torn to warm, sticky and working well, and if you over do it, to melted and squirmy on the track as you lower the pressure. When it feels good, warm and sticky, measure the hot pressure, let the bike cool of, measure the cold pressure and there you have it.

Team ESE made a mission of doing it this way at Mt Wellington one day, and found 15 psi cold was generally to low for us and 18psi cold is about right for me. Others have slightly different preferences, a psi or so cold makes a big difference. Later we found some days the weather was to cold and nothing worked.

Kaitoke being a longer faster track I started at 20psi cold but the tyres never got the warm sticky feel that I was used too, I never got them into the zone all day, and they never got the Mt Wellington look, tricky things tyres and suspension.

Good Luck.

.

[fi5hy]

will try that I have one trye left so will give that a go I also have two shocks to try one from a zx9 and the other from a nc30

Attached are the latest to die in the hands of the LONCIN in one day

New Saturday Bin Sunday


Rear Front Rear