Tyre wear /Suspension setup

Hi guys,
I don't like my odds of a sensible answer, but you don't know until you
ask:

04 Cagiva X Raptor. Running 180 rear, 120 front (Bridgestone I think, I
can check if you think it's relevant), I've got wear marks right to the
edge on the rear, but I've still got about a finger's width of
untouched tread on the front. I seem to recall that indicated that I
didn't have the suspension set up right - comments, suggestions ?

I've not taken it to a track yet, just road riding, have about 3500Km
on it. Started setting up the suspension this weekend, the front was
too stiff so I backed off the preload a fair bit (sag is about right
now) and the compression damping a little bit. It was a lot better up
McCarr's Creek road today (the benchmark for rough as crap roads in
Sydney), although I think it could go a little softer. I've left the
rear stock so far, although I suspect it could be backed off a little
(I'm doing as much 2 up riding as solo and the setup seems about right
for two up).

JL
(Burnie will undoubtably be amused to know it's going back for it's
first warranty repair next week - ironically though it's because the
engine is weeping a bit of oil, no problems with the Italian bits
(touch wood) just the japanese lump

 

Don't worry about it. Front tyres curve over a wider arc than rears,
meaning it takes a lot more lean angle to get the very edge of the front
tyre tangential to the tarmac than a rear.

A more sophisticated answer would be to also acknowledge tyre
deformation, and point out that the front tyre works the hardest, and,
thus, deforms the most, when braking, most of which is done with the
bike upright. In a corner, all the front tyre has to do is not slip out
sideways.

Conversely, the rear will also be having drive put through it when leant
over, causing it to be flattened out at the contact patch more than the
front.

If the rear was getting to the edge while there was still a whole heap
(ie, a lot more than a finger's width) to go at the front, I'd be
diagnosing an overly tail-heavy weight distribution (being a nudiebike,
the Raptor would be rear-biased as a matter of course), but, if that was
the case, there'd be symptoms other than tyre wear patterns to signify
it. For example, you'd need to use every milimetre of the width of those
wide bars to hold the bike down when on the gas in a corner.

 

OK, ta, just seemed to recall being told/reading something about
significant wear difference meaning a suspension setup issue.

X Raptor has the ride height jacked up an inch over the stock V rap
hence having a sports bike style front heavy weight distribution (and a
fairly aggressive rake and trail), hence the factory steering damper .

JL

 

That is prettry standard wear (on my VTR, Raptor and SV)
With Bridgestone BT56 and BT010 I used to run 36 front 42 rear one up.

Some sort of seal behind the starter motor ?
(seem to remember something vaguely about that...)

Insist that they use Suzuki parts (seriously) if Feeneys do not have
the Cagiva parts in stock, otherwise you will be waiting months (also
seriously) while they ship parts from Japan to Italy and then to
Australia.

 

Hmm could be interesting, technically I can't insist on Suzuki parts,
they have every right to demand to use "genuine" Cagiva parts (even if
they are the exact same parts). We'll see if they're reasonable or not
on Monday (when I find out how long it'll take to get the parts in).

Don't think it's the seal behind the starter, looks like a gasket at
the base of the cylinder head to me (where the cylinder joins).

JL
(getting them to do the power commander fit and dyno tune at the same
time)

 

OI! I like ham and pineapple pizza...!

GB, non poof

 

OH ! Ok, thanks mate, I wouldn't have known otherwise. My cynicism was
obviously well placed

JL
(who am I supposed to turn myself in to ?)

 

Hmm, well we'll see I guess. These guys are the biggest MV dealer in
NSW if I'm not mistaken, so they might have a bit more swing.

JL
(have you spoken to consumer affairs yet ?)

 

coming from a proscuitto, spinsach and fetta pizza eatingm handbag carrying
bum muncher, thats pretty ripe

corks

also likes pinapple on my ppizza , but anchovies too which makes me well
hard

 

Compared to the squishy doughnut look you have in photos?
There are rules about pizza.
If it has ham or pineapple on it, it is meant for children or girls blouses.
Real pizzas don't have either.

If it doesn't have anchovies, it is NOT a pizza.

Theo

 

Well, I'd like to report back that you were definitely on the money
here (although there were no turn in issues or wanting to stand up in
the corner issues), however the softer front has indeed widened the
wear mark on the front, indicating the weight was insufficiently able
to be moved forward I guess.

JL

 

hehehehehehe

i just couldnt avoid giving KD a rev up

like a moth to the flame

;-)

 

Goes in for repairs Thursday morning, I'll pick it up Saturday, I guess
they found the shelf labelled "Suzuki spare parts"

JL
(you might want to ask some serious questions about why they haven't
got approval to do your repair yet - 2 months is bloody ridiculous)