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swanman
26th March 2005, 17:11
Had a great time at Puke today. However never before have I had so much front end chatter. I first got it breaking into Castrol so much so that I ran onto the grass. I then increased front preload and changed my entry into Castrol, no probs. However braking hard from 270 down at the end of back straight would have my front end chattering like mad. So bad I had to release the brake and reapply it a number of times to clear it before I could take the hairpin. What's going on there? And how do I stop it happening?

I have had it happen to me a couple times on the road too.

geoffm
26th March 2005, 17:24
Had a great time at Puke today. However never before have I had so much front end chatter. I first got it breaking into Castrol so much so that I ran onto the grass. I then increased front preload and changed my entry into Castrol, no probs. However braking hard from 270 down at the end of back straight would have my front end chattering like mad. So bad I had to release the brake and reapply it a number of times to clear it before I could take the hairpin. What's going on there? And how do I stop it happening?

I have had it happen to me a couple times on the road too.


Are the forks bottoming out? Tie a cable tie around the shiny bit and that will tell you how far the forks are moving.
What weight oil are you running? How much? decreasing the air gap will increase the spring rate at the end of the travel without making the beginning harsh.
Do you have adjustable damping - what settings?
Geoff

swanman
27th March 2005, 07:05
Are the forks bottoming out? Tie a cable tie around the shiny bit and that will tell you how far the forks are moving.
What weight oil are you running? How much? decreasing the air gap will increase the spring rate at the end of the travel without making the beginning harsh.
Do you have adjustable damping - what settings?
Geoff

I am sure the the forks are bottoming out. The oil I am running is standard OE stuff, the bike is only 6 months old. I am sure I can adjust the problem out, as I have adjustments for rebound, compression and preload. The question really is what adjustments to make?

FROSTY
27th March 2005, 07:33
What tyre pressures are you running.? could be that diddn't help

swanman
27th March 2005, 08:02
I decreased pressure to 2.2 on the front, 2.5 at back. The tyres seemed to behave well, good grip, minimal sliding.

FROSTY
27th March 2005, 08:17
gee mate it doesn't make sense that a modern sports bike would be that soft in the front end. It almost sounds like the forks are too soft for the track.
Have ya done the sag test ?
Its funny it should be chattering in castrol -its such a smooth open corner now.
The hairpin I can understand

StoneChucker
27th March 2005, 11:04
I'm so glad I'm not the only one. I've had the same problem for ages, but only in a certain situation. Downhill corners, from memory ONLY right handers... It's so bad that when it comes I have to stop braking, and re-apply. My best description is a jackhammer... I've had it in to Sawyers twice now, and they say nothing is wrong...

Maybe it IS just settings, but like you I have no idea. Come to think of it, it probably is settings, since I'm alot heavier than the rider it's set up for. I think we need to get it sorted soon, it's a bloody big hazzard. As you say, I've almost crashed because of it (ran out of road while releasing break, and fighting the jackhammer).

Weird thing, I have no problem on the straights, and in uphill corners... Don't you just LOVE these types of issues??

Sensei
27th March 2005, 11:27
Here are some Setting's for a 04 R1
Front
Preload = 3 lines showing
Rebound =7 clicks out
Compression =9 clicks out

Back
Preload 8 of 9
Rebound = 21 clicks out
Compression = 7 clicks out

Note you can drop the Fork tube to 5mm through the Triple clamp as well if needed .Have setting's for 97 -04 R1's
Have used the setting off this site to set up my GSXR1000 & are excellent


SENSEI :drinknsin

StoneChucker
27th March 2005, 11:44
Thanks Sensei.

But don't you have to have Sag set for the other settings to be of much benefit? Or will those settings help in the meantime, until one were to get their sag set?

I'm probably going to pay someone to do it, would take me too long to fiddle with settings I know nothing about :confused:

I have seen pages of setting before, but never really got around to changing them. Mostly because I'm inherantly lazy, and it would take up time I could be sleeping or riding :whistle:

swanman
27th March 2005, 12:47
Here are some Setting's for a 04 R1
Front
Preload = 3 lines showing
Rebound =7 clicks out
Compression =9 clicks out

Back
Preload 8 of 9
Rebound = 21 clicks out
Compression = 7 clicks out

Note you can drop the Fork tube to 5mm through the Triple clamp as well if needed .Have setting's for 97 -04 R1's
Have used the setting off this site to set up my GSXR1000 & are excellent


SENSEI :drinknsin

I'll try these settings, they certainly would appear to be quite stiff. Unfortunately in order to replicate the issue I need to brake hard from 270kmh, hmmm. Wonder if that would stand up in court. Do you have the site address for these settings? Ta

swanman
27th March 2005, 12:53
Yep this is the same problem for sure. I weigh just under 90kg so that might have an effect too. Funny that in the journos' write ups there is no mention of it. I reckon you can dial it out so I'll try Sensei's settings, am just concerned that stopping the front end chatter may make the bike harsh or too firm. We'll see.

StoneChucker
27th March 2005, 12:57
let us know how you get on won't you?

Sensei
27th March 2005, 12:57
Yep WWW.Sportrider.com go to suspenion setting area
SC have left my GSXR at standard Sag setting's which is easily checked then put the setting's for my bike onto it . Put 2 less Rebound & left the rest .
SENSEI

pritch
27th March 2005, 14:00
The following link has some good information bearing in mind it was obtained on their bike with their rider etc etc. But if you find yourself lost it might be a place to start...

http://www.sportrider.com/bikes/146_susp_settings/

Two Smoker
27th March 2005, 19:00
You have to set the sag to about 23-25mm front and rear... once that is done, you can play with the preload and rebound...

Sounds like you need to adjust the preload Swanman, then increase the dampening slightly... But on the track its different. I have my ZXR400 hard, i wouldnt like to ride it on the road as the suspension is set up now...

FROSTY
28th March 2005, 09:31
I agree with TS. I rode my 400 on the road once -nearly destroyed my kidneys.
That said it does sound like an inherant problem if 2 90kg riders are having the same problem.
It would have been interesting if it did the same thing with me then MR on the same bike--me being 75 ish kg and him being lighter still
I wonder if the first place to start after fiddling with settings might be a heavier fork oil.??

White trash
29th March 2005, 12:35
Loose steering head bearings.

**R1**
29th March 2005, 15:38
Loose steering head bearings.Id have to agree......mine only last about 3000k's.

all the R1's are bad for steering head bearings....and clutch's they last about 12000k's

StoneChucker
29th March 2005, 21:01
Loose steering head bearings.
Fuck you prick, that sounds expensive!!!
Say, that sounds like an item covered under bike guarantee??? :cool:

FROSTY
29th March 2005, 21:09
loose bearings are just a matter of adjustment. Worn out bearings are a different kettle of fish.

**R1**
29th March 2005, 21:14
loose bearings are just a matter of adjustment. Worn out bearings are a different kettle of fish.waste of time adjusting them, each time i have adjusted mine they need doing again in a day or 2.

Sensei
29th March 2005, 21:27
Yea need to tighten mine now . Been doing more & more wheelies as of late .
Not as good as the Dirt bike one's of 30k + But very nice 1 k one's so as not to get pinged by the Fuzzobumballs .
SENSEI

White trash
30th March 2005, 08:28
Fuck you prick, that sounds expensive!!!
Say, that sounds like an item covered under bike guarantee??? :cool:

No.

They normally wear prematurley due to cack handed wheelie attempts.

swanman
30th March 2005, 20:13
No.

They normally wear prematurley due to cack handed wheelie attempts.

Quite possibly right about the wheelies. Though I had this prob before I started doing wheelies. I also give my headstock a good rock with the brake on now and then and there appears to be no play.

I'll make the suspension adjustments and go for a test run or 2 and see if the prob persists.

swanman
30th March 2005, 20:15
Id have to agree......mine only last about 3000k's.

all the R1's are bad for steering head bearings....and clutch's they last about 12000k's


Expensive/difficult to change?

StoneChucker
30th March 2005, 22:29
No.

They normally wear prematurley due to cack handed wheelie attempts.
HAHAHA, thanks for that pot, I needed a chuckle...
Sincerely
Kettle

PS: I'm the same as Swanman, had this before I allegedly started wheelie practice

White trash
31st March 2005, 07:37
Swan, are you sure you're experianceing front end chatter? It tends to be most apparent when turning a bike, not straightline braking.

If you read any WSBK or MotoGP loosers result and you'll find them normally talk about "chatter". The Suzuki team has complained about it for the past twelve months and they have no idea how to get rid of it.

If I had to guess, I'd say it sounds like you're finding compression lock ups when braking really hard, same as I do.

swanman
31st March 2005, 08:06
Swan, are you sure you're experianceing front end chatter? It tends to be most apparent when turning a bike, not straightline braking.

If you read any WSBK or MotoGP loosers result and you'll find them normally talk about "chatter". The Suzuki team has complained about it for the past twelve months and they have no idea how to get rid of it.

If I had to guess, I'd say it sounds like you're finding compression lock ups when braking really hard, same as I do.

How does the compression lock up? If it is that can you adjust the compression damping?

FROSTY
31st March 2005, 08:09
Possibly related -I was getting horific head shake outa mella yella at pukie.
I had my REAR shock rebuilt and softened and suddenly no more head shake.

**R1**
31st March 2005, 08:34
Expensive/difficult to change?

$115 for new bearings, and piss easy to change..:niceone:

White trash
31st March 2005, 09:26
How does the compression lock up? If it is that can you adjust the compression damping?

Nah sorry mate, I meant the rear wheel skipping and bouncing due to the engine compression trying to lock it up when the weight is off it.

Fucken nasty, horrible experiance which means the bike can't be turned 'till it settles.

swanman
31st March 2005, 09:34
Nah sorry mate, I meant the rear wheel skipping and bouncing due to the engine compression trying to lock it up when the weight is off it.

Fucken nasty, horrible experiance which means the bike can't be turned 'till it settles.

Yeh I get a lot of rear wheel lock and slide on quick down changes from speed. Better with a slipper clutch.

scroter
31st March 2005, 12:28
Had a great time at Puke today. However never before have I had so much front end chatter. I first got it breaking into Castrol so much so that I ran onto the grass. I then increased front preload and changed my entry into Castrol, no probs. However braking hard from 270 down at the end of back straight would have my front end chattering like mad. So bad I had to release the brake and reapply it a number of times to clear it before I could take the hairpin. What's going on there? And how do I stop it happening?

I have had it happen to me a couple times on the road too.

sounds to me like its bottoming out. check your sag on the front. static sag should be about 20% of total travel and rider sag about 30%. set the static sag and then check the rider sag if it comes out at more than 30% then your springs are too soft. buy heavier ones or you can cheat by raising the fork oil level.

note: adjustments mean nothing if your spring rate is wrong all they can do is make a compromise.