Lets see your track/race videos!

[reciprocity]

Rick,

I know it was a while ago but I noticed that this bike "the muffin" wanted to let the back end come around quite easily when I rode it.

it was a similar, mid-corner movement that you experienced there.

[Wingboy]

Some info on the tire would be helpful... what was the ambient temperature, tire pressure, rubber compound, warmers, etc... kinda looks like a cold tear.

The tires are BT002r's med front soft rear with that being the 4th day on them.The temp was 34c,28psi front 30psi rear.That pic is after a few really slow (for me) laps on sunday after we put the bike back together enough to just get back out there.I expected to see the tires all smooth from my low speed.Weird??!!

Rick,

I know it was a while ago but I noticed that this bike "the muffin" wanted to let the back end come around quite easily when I rode it.

it was a similar, mid-corner movement that you experienced there.

Any input you can give me on this would be appreciated.The bike has handled great.Yes it's got enough torque that it's easy to break the rear loose on exit,especially at a track like tmp.But at speed thru t1 Calabogie?I know a slipper clutch would be a great addition,but this was mid turn constant throttle.Listen to the vid Donnie and maybe you can find something stupid that i did.I value your advice and or criticism.

[R1Guy]

The tires are BT002r's med front soft rear with that being the 4th day on them.The temp was 34c,28psi front 30psi rear.That pic is after a few really slow (for me) laps on sunday after we put the bike back together enough to just get back out there.I expected to see the tires all smooth from my low speed.Weird??!!

I've never used that tire but I know someone who has, depending on whether you use tire warmers or not the cold pressure should have been set somewhere around 27/28 front and 25/26 rear ... not saying this was your problem but your tire looks like it was over-inflated at 30psi and could be a "cold" tear .... best bet is to consult a tire guru for sure. my .02

*Fixed*

[ShiftyEh]

Not to change to topic to tires, but my understanding is too little pressure causes heat tearing due to a larger contact patch and the tire building more heat. Too much pressure causes cold tearing as the tire can't get up to heat. Feel free to correct me if I'm wrong but I thought that's how it works? Again, best thing to do would be to contact a tire guru.

[R1Guy]

Yes you are correct...

[ShiftyEh]

Oh ok, thank's for clarifying. Hope you didn't take offence, I still have lots to learn myself with tires. That is actually the entent of my knowledge to be honest... After the last day, I had a bunch of peices of rubber slightly larger than "nerds" in my lower fairing, is this typical?

[reciprocity]

Not to change to topic to tires, but my understanding is too little pressure causes heat tearing due to a larger contact patch and the tire building more heat. Too much pressure causes cold tearing as the tire can't get up to heat. Feel free to correct me if I'm wrong but I thought that's how it works? Again, best thing to do would be to contact a tire guru.

Too much pressure will not cause the tire to stop building heat.

[ShiftyEh]

Interesting, but it wont build heat through the carcass of the tire though correct? Resulting in the cold tearing as the surface has a higher temp then the body of the tire?

[reciprocity]

Interesting, but it wont build heat through the carcass of the tire though correct? Resulting in the cold tearing as the surface has a higher temp then the body of the tire?

The tire pressure will not cause the tire to stop building heat through the carcass, or cause it to cold tear.

Put identical tires on the same tire warmer, with the same temp setting with 1 at 10psi and the other at 50psi and they'll both reach the same operating temperature in the same time frame.

if you rode them without warmers, the lower pressure tire may build heat SLIGHTLY more quickly, but the extra pressure isn't going to stop one tire from not heating up and cold tear.

[fastar1]

I don't want to pretend that I know anything on the subject, but even so it's looks to me that you're trying to extrapolate too much from very little info. A cold tear is just a time of wear that is characteristic to tires that are not up to proper operating temperature. It doesn't tell you anything more specific than that, there can be several reasons why a tire isn't up to temp. You might as rationalise backwards forever to try and figure out if the cold tear was due to an excessive number of cows grazing in farmer John's field on the day you were born. But you can't because there's no direct relation to that info.

[Amazon]

Here's a video of me doing the last session of the FAST course at Shannonville. I wish they would let us pass in more then 3 spots. Oh, and I have no idea how to edit my videos, just uploaded it yesterday to youtube

[GRAYZ]

I went out to look at the bike again with a clear head.I did get the thing back on the track sun for one "slow" session (3 min+ laps).Here's a pic of the tire.Something wrong for sure.

That's quite a debris field leading out to the edge of the tread... hard to tell because a photo of the left side of the tire before going back out would have given good information, and I've heard that after a few slower laps you can sometimes "heal" a nasty wear pattern. And at Calabogie? That place usually turns my tires to hockey pucks before I wear them out.

Just playing with this, I could be wayy off here because I'm going on a lot of assumptions... but that debris field could have been caused by higher surface temperatures that melt the tire and push it out to the sidewall. From the direction of the debris pattern (90 deg to the rotation of the tire) it's happening under acceleration, and the torque of the Ducati will definitely go along with that assumption. It can be caused tires that are over inflated or a shock that needs faster high speed compression damping. So the pattern could have been caused by a rear suspension that doesn't dampen high speed forces when leaned over and forces the tire to deal with it. Or not.

Hope this is in some way helpful...

[toybm]

A short clip from last weekend at TMP, Wave then near highside http://www.youtube.com/watch?v=Mvu1RtegobY .

[Jia]

wow nice save!

[GRAYZ]

Tank slapping 101! lol

Glad it ended the right side up!

[SunnY S]

Oh track expert teachers.....Please educamate me.....Hows the best way to "save" this? Or just sit and pray?

[kneedragger88]

Like with any "almost" crash the only answer is to gas it. What happens is the back slides out. The first instinct is to chop the throttle (which is what was done in the video) this immediately pitches the centre of gravity forward unloading the rear and causing it to gain traction and seeing as its sliding sideways at the time it generates a highside scenario. This wasnt a "speed wobble" it was a near highside.
By using the throttle (if you have enough motor) you keep the rear sliding/spinning until you can get the bike back on the centre of the tire and heading in the right direction. Its all about body position, steering and looking where you want to go and a liberal use of throttle.
This is why you see a crap load of highsides on 125 GP bikes. High corner speeds-Heavy lean angles-Limited available engine power perfect recipe.
BTW highsides hurt like a mofo I highly dont recommend them

[GRAYZ]

Thursday's track day at Shanny, in near record heat, gave all new meaning to "hot" lap! Still was loads of fun out there with everyone! Thought this tune was appropriate

http://vimeo.com/26794871

[R1Guy]

A short clip from last weekend at TMP, Wave then near highside http://www.youtube.com/watch?v=Mvu1RtegobY .

There is a wicked pavement dip where that near highside happened... stay away from it (go inside)! I've had the tire slip out there, (it's almost a tire hop) a few times and it's not a fun experience.

[stnd]

Another from Jul 21 @ Shannonville - Long. First video.