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Lou Girardin
1st February 2004, 14:00
My RF9 tended to push the front end in corners. I noticed recently that this has reduced a lot, it seems to have got better as the sides of the front tyre wore into a triangular shape and put more tread area on the road.
Does this make sense?
Any ideas on how to set it up to reduce the pushing with new rubber.
Lou

wkid_one
1st February 2004, 14:41
Shape of the tyre?

Yep - made a HUGE difference on the VTR as to whether the tyre was flatter (like D208) or more parabolic (Rennsport etc)......makes entire sense.

As for set up - don't ask me

Big Dog
1st February 2004, 16:51
My RF9 tended to push the front end in corners. I noticed recently that this has reduced a lot, it seems to have got better as the sides of the front tyre wore into a triangular shape and put more tread area on the road.
Does this make sense?
Any ideas on how to set it up to reduce the pushing with new rubber.
Lou
The ideal is to retain the profile it comes with. Sounds to me like you need to get your suspension calibrated / set up to your weight. I may be wrong but it sounds like your cg is too far back for your riding style or your forks are too stiff. Both of these could be fixed by means of relatively simple adjustment.... unless you are really sure of what your doing get a pro involved. the big thing with suspension is before you change anything record all of your settings so you have a base line to go back to if it all goes pear shaped.

PeteThePom
1st February 2004, 20:46
My RF9 tended to push the front end in corners. I noticed recently that this has reduced a lot, it seems to have got better as the sides of the front tyre wore into a triangular shape and put more tread area on the road.
Does this make sense?
Any ideas on how to set it up to reduce the pushing with new rubber.
Lou
Unless you push your bike really(and I do mean really) hard and or your a lard arse of a string bean, the standard suspension settings will work perfectly for you. They also give you a good base line to start from if you insist on changing them. And as big dog said, write down what u started out with, that way if it all goes tits up you can put it back where you started from!

RULE NO.1 of suspension tweaking.....ONLY change one setting at a time.
I spent an entire weekend trying to improve the handling on my ZRX and after all that I came up with a setting of increasing the pre-load by 2 notches and backing off the compression damping by 2 clicks

I'd also check to make sure that the forks haven't been dropped through the yokes to accomodate a rider lacking in leg, it's a cheap bodge that a lot of shorter riders do, this also upsets the stance of the bike as it pushes the weight of the bike further forward which can make the front tyre work harder than it should.

Dave
2nd February 2004, 13:31
I'd also check to make sure that the forks haven't been dropped through the yokes to accomodate a rider lacking in leg, it's a cheap bodge that a lot of shorter riders do, this also upsets the stance of the bike as it pushes the weight of the bike further forward which can make the front tyre work harder than it should.

Actually, Dropping the forks through the tripple clamps more steepens the angle on the front wheel and would make the problem better.
ie. less tendancy to understeer

James Deuce
2nd February 2004, 14:25
Actually, Dropping the forks through the tripple clamps more steepens the angle on the front wheel and would make the problem better.
ie. less tendancy to understeer

Correct - though if the rear shock linkage has been altered to lower the rear end this would either maintain the stock geometry if the front was lowered as well, or increase rake at the front adding to the tendency to push the front.

I would dig the manual out, return all suspension settings to stock and then work on setting up static sag (via pre-load - preload doesn't stiffen the spring it makes the suspension start working further down it's stroke)to about 25-30mm, and then add or remove rebound and compression damping as necessary. Make ONE change at a time and then test each change, carefully documenting as you go. Find a nice set of twisty bumpy roads to test your settings. I use the Korokoro hill in Lower Hutt. Good for scubbing in new tyres too.

Lou Girardin
2nd February 2004, 15:56
I started with factory settings, then went to; front,one ring more preload, 1/2 turn less damping. Rear 1 notch more preload, standard rebound, 1/4 turn less comp damping. Static sag is within spec at these settings for my weight.
Lou

wkid_one
2nd February 2004, 16:04
Me chucked me forks thru the triples by 5mm - feck - was always going to be a silly idea on the R1 anyway, but I had a new Head Stem Stand and wanted to test it....you know how it goes.

Sheese - she turned on a dime tho - made for an eventful ride up the 'taka's. Only once tho......talk about heart in your throat....steering happened about 2 secs before you thought about it.

I agree tho - take the settings back to standard.

Try emailing Peformance Bike Mag - they always have the on epage set up guide. They sent the one for the 02 R1 thru to me

Lou Girardin
2nd February 2004, 20:01
You can't raise the forks through the yokes on the RF or I would've tried it. I used Performance Bikes info to set up static sag. I'll see how it is on the new fr tyre and go from there.
Lou

mangell6
2nd February 2004, 20:11
Lou,

My RF900R was always very susceptable to tyre pressure and I knew when the pressure was low as the front tended to push out. Had Dunlop sports tourers, 205s I think they were. They were fine on the track as well.

Remember that the RF is a heavy beasty, but oh so forgiving.

Mike

riffer
3rd February 2004, 07:28
My RF900R was always very susceptable to tyre pressure and I knew when the pressure was low as the front tended to push out. Had Dunlop sports tourers, 205s I think they were. They were fine on the track as well.
Mike
Maybe its a Dunlop Sportmax 205 thing. I have the same problem with my fizzer. Even 3 lbs difference and it corners like a pig.

James Deuce
3rd February 2004, 20:13
I started with factory settings, then went to; front,one ring more preload, 1/2 turn less damping. Rear 1 notch more preload, standard rebound, 1/4 turn less comp damping. Static sag is within spec at these settings for my weight.
Lou

Sounds like you have it covered.

I'd go with Tyre pressures like mangell says.

Lou Girardin
4th February 2004, 05:57
OK. I'm running 36psi now, maybe another 1 or 2?
Lou

Blackbird
4th February 2004, 06:15
Lou, you don't say what tyres you used but the D220's my Blackbird came with simply didn't have a sufficiently strong carcass construction for a heavy bike and the front tyre triangled off due to deflection of the casing. It also tended to push the front end when I was getting a move on. The Avon Azaro ST 45/46 combination fixed this, and I also stuck a 6mm plate under the rear shock to speed up the steering as this is a recommended 'bird mod.

MacD
6th February 2004, 10:29
Lou, my RF900 came with Dunlop D208's which seem to work well for me. I was running them at 36psi front and rear (based on the swing-arm pressure recommendation plate), but the Dunlop Fitment Guide (http://www.dunlopmotorcycle.com/fitmentguide.asp) suggests 36 front and 42 rear, so I've bumped up the rear pressure to 40psi initially. I haven't had the opportunity to really test the difference in feel yet, but my first impression is that the handling is better.

Lou Girardin
11th February 2004, 05:50
Update time, I've fitted a new Avon ST45 front. Took it up SH16 and it is still holding a tighter line, as with the old tyre. I can only put the improvement down to backing off the front damping a tad. That's a bit surprising, but there you go!
Lou