Yamaha FZ-09 Forum banner

1 - 13 of 13 Posts

·
Registered
Joined
·
137 Posts
Discussion Starter #1 (Edited)
Hi All


So I managed to get my first track day on the 09 at Hampton downs here in NZ in the novice group.
It went great and I had a fun evening, the bike was great, better than me at least.
Did have one slide but that was more me moving the throttle after I hit the pegs a bit hard and tensed up.

I'm now a little confused on tire wear and if I have it all wrong.
I had the following wear pattern on my T30's (after I rode home so perhaps not 100% accurate). Pressures are 30F/36R psi plus I have new front springs/oil and a zx10 rear shock

IMG_20150205_101101877_HDR[1].jpg
IMG_20150204_085308572[1].jpg

I was told by the "guy" at the track my pressures were about right, but looking at the following article
Race Track Motorcycle Tyre Wear Guide - Types and Causes

It looks more like cold tear to me, could anyone enlighten me as to what I'm looking at, as I am planning to do another track day and would like to ensure I'm at least half way there.
I accept there may be no wrong or right answer, but any advice is much appreciated.

Cheers;)
 

·
Registered
Joined
·
137 Posts
Discussion Starter #2

·
Super Moderator
Joined
·
5,616 Posts
Cold tearing certainly looks like a possibility, as the rear tire pressure is set about 6 psi too high in my opinion. I would try 30/30 cold pressure. I would also increase the rebound setting (clockwise turning of the adjuster screw) to slow down the rebound. It looks like you have some uneven wear on the tire where the leading edge of the tire grooves are being worn faster than the trailing edge.
 

·
Registered
Joined
·
137 Posts
Discussion Starter #4 (Edited)
Cold tearing certainly looks like a possibility, as the rear tire pressure is set about 6 psi too high in my opinion. I would try 30/30 cold pressure. I would also increase the rebound setting (clockwise turning of the adjuster screw) to slow down the rebound. It looks like you have some uneven wear on the tire where the leading edge of the tire grooves are being worn faster than the trailing edge.
Hi triplethreat

Thanks for the sage advice, I had seen your previous post recommending 30psi so will defiantly give that a go next time,.will know not to listen to the track expert again

I have also already upped the rebound by half a turn and will see if that improves.
It might not have been helped by the fact I had the shop set the sag when I got the forks springs replaced. Finally got a friend to help me check today and it was at way out.
55mm at the back and 47mm at the front, so I've remedied that, so hopefully should all make a bit more stable.
Have to say it didn't feel too out of control on the track and she certainly rips out of corners at any revs, shame she tops out at 220KMH as I lost out every time down the straight.
 

·
Super Moderator
Joined
·
5,616 Posts
Boro....just so you know, sometimes once a tire starts wearing unevenly like that, no amount of adjustment will straighten it out....depends on how early you catch it. So don't be discouraged if you can't get it on that tire, but watch it very closely after you mount a new one.
 

·
Registered
Joined
·
656 Posts
I'll agree, for street tires, 30/30 cold is a safe starting point. You're going to generate a lot more heat in the tires on the track than on the street, so hot, that pressure might be 32/33+. If you started at 30/36, your rear could have heated up to 38+. That's way too high IMO for track. You'd be getting a much smaller contact patch.

I have my rear shock 1/2 turn from full rebound, and I find it still too fast.

...I miss the track :(
 

·
Registered
Joined
·
3,068 Posts
Agree with everyone.

My cold PSI were F30 R27 last weekend. End up F34 R32 Hot. (F +13%, R + 20%)



Question for Triple...

The groove on the edge of the tire wear on the leading edge and the second row of grove wear on the trailing edge. Those are a set of brand new Q2s I just installed, minus about 50 miles of road just to break them in. ZX-10 reb setting are like last time, 1.25 open from full soft. Bike handle great to me... Only thing I change from last track day was -1T of rear preload (was at 33mm rider sag) I feel like the rear end set better when I roll on the throttle coming out of a turn. I had 29mm from the bottom of the tyrap to the edge of the front fork (about the same as everyone else in the paddock) and about 25mm before the rear shock bottom out.

Not that think about changing anything but just wondering and have your honest opinion. Thansk
 

·
Registered
Joined
·
2 Posts
To me looks pretty much normal track wear. Too high tyre pressure tho that's why you had a slide probably. I always set mine to 28-29 Psi hot rear and 30-31 hot front.
 

·
Registered
Joined
·
137 Posts
Discussion Starter #10
Thx guys, guess I'll always keep learning...30 F and R. In a couple of weeks I'll try those and see how she goes.
 

·
Registered
Joined
·
37 Posts
Nice to see a mt09 on kiwi circuits.....I m looking to go down to Taupo in a couple of weeks and have a play..i lol be getting suspenders and tyres first though!!
Drop me a line if you fancy a day down that way....
Gazza
 

·
Registered
Joined
·
137 Posts
Discussion Starter #12
Hi Jojo


Will do , have to say that the bike was a hoot on the track, not sure how fun it would have been with OEM tires/suspension, bit with a bit of work she flies out of corners. It's just a bummer when you hit the rev limiter and all the straight line merchants come flying past again.
 

·
Registered
Joined
·
244 Posts
Boro... you're in LUCK, because Dave Moss (AMF Championship racers and suspension God) is in NZ the end of February and beginning of March!!!
Check his FB page... here are the details. BTW US riders check out his Suspension class schedule as well, for merely $350 you get the best of the best real suspension podium winner to teach you how to setup your bike for yourself.

DMT Suspension School | Feel The Track


Dave Moss
------------------------------------------------------
NZ riders! Important date change!

Taupo suspension school new date announced by the track. Test day moved to February 26th.

Please share the date change
Open dates for events are Feb 24th and March 2nd (daytime only - evenings not available). If you want an event scheduled, please contact me directly: [email protected]

Suspension schools:
February 26th at Taupo
February 27th at Ruapuna
March 6th at Pukekohe

Limit of 10 riders per school, cost $350. All day learning between classroom and on track testing with debrief after every track session. If you want to book in email me directly: [email protected] to secure your spot. More information on the school here:

DMT Suspension School | Feel The Track

February
19 Trevor Pierce Yamaha evening seminar 6-8pm
20 Test day at Ruapuna with trackside tuning to competitors
21 Ruapuna sound of thunder with trackside tuning
22 Ruapuna sound of thunder with trackside tuning

23 possible evening seminar (TBA) in Palmerston North
24 open
25 Taupo (possible evening track walk / class at Taupo)
26 Taupo test day / suspension school **
27 Ruapuna test day / suspension school ** and Evening event at First European
28 First European Dealership suspension tuning street ride

March
1 Private event
2 open
3 AMC seminar
4 open
5 Rideforever.com.nz
6 Test day at Pukekohe / suspension school **
7 Cycletreads seminars
8 Potential road ride suspension tuning session Auckland (8 riders)
9 Return to US from Christchurch @ 6.20am


Thanks in advance for sharing the post!
------------------------------------------------------
 
1 - 13 of 13 Posts
Top