Crazy question- handlebar rebound

Motor Head wrote: The Dun 404 seems like a decent tire, I've had them on my KZ1000 with the Vetter set up with no Tire issues. I just ordered a set for the Concours also, but am in process still....

The favorable results might be attributable to fitment of 404's on both wheels, and not just adding a new 404 front tire while keeping the existing rear tire (of whatever persuasion.)

Some tire designs seem to present steering stability issues, especially when not paired with another of the same design.

Am also thinking that at speed, the fairing contributes to front end stability.

Good Fortune!

Ok, from the horses mouth, no doubt attorney tempered. Its an email, so read from bottom up.
Seems I'm "ok" but would have been better suited to a salesman better suited to knowing what the feck they're selling.
I'll try..much to my chagrin running the tires at 40 pounds, the max rating, run for an hour, check the temp**

Hi again Claude,

Here is a comparison of the load carrying capacity of the tires....Recommend you weigh your Kawasaki loaded and compare>

Elite 3....front.....MM90-19 570 @ 40 psi
Elite 3....rear.....MT90B16 830 @ 40 psi

D404.....front.......100/90-19 507 @ 41 psi
D404.....rear.......130/90-16 677 @ 41 psi

As you can see, this is quite a difference.

Again, if you wish to discuss, call Dunlop Consumer Affairs @ 800-845-8378

regards,
Consumer Affairs
Dunlop Motorcycle & ATV Tire Division

Thanks for the quick reply.
The KZ1100 is the "Vetter version" shaft driven with the large front fairing, rear bags/trunk.
Still good to go with the load?
thanks again
Claude

On 5/24/2012 10:37 AM, consumeraffairs@dunloptire.com wrote:
Good morning Claude,
Thank you for taking the time to contact Dunlop Motorcycle & ATV.

We do not see any reason why the D404 should not be used on your Kawasaki KZ1100.
Difference between Elite 3 and D404 is the Elite 3 has a heavier load carrying capacity and
should provide better mileage.
If you are carrying a heavy load on the motorcycle, then the Elite 3 will be a better choice.

The warranty covers materials and workmanship for six years (from the date of manufacture)
or until the tire is worn out.

Please contact the dealer of purchase for and evaluation of the tire in question.
The dealer has the ability to adjust when a warrantable condition exists.

Should you or the dealer need further information or assistance, please call Dunlop Consumer Affairs @ 800-845-8378.

regards,
Consumer Affairs
Dunlop Motorcycle & ATV Tire Division

Goodyear/Dunlop Tires N.A., Ltd
PO Box 1109
Buffalo, NY 14240
Ph: (800) 845-8378 Fax: (716) 879-8425
name: Claude

state: Ohio
zip: 44256
phone:
fax:
website:
interest: Retail
year_make_model:
comments: Hello, I had installed at the suggestion of a local shop a
pair of Dunlops on my bike- D404's.
The bike in question is a 1981 Kawasaki KZ1100 A with a vetter fairing-
I've had some handling problems and realized they are not suggested for
this bike.
Are they safe, or am I in danger of imminent failure? thanks for
answering this question.
CWG

All I had was bathroom scales, drove the front wheel onto that, and 250# with me leaning forward.


**

Tire Pressure:

You'll get a lot of opinions on what tire pressure to run, but the correct tire pressure for you is not a matter of polling other rider's opinion. Here are the basics you'll need to decide for yourself. "Dennis Smith of Dunlop's Sport Tire Services recommends an increase of two to four pounds in front tires and six to eight in the rear (sportsrider.com)". While the most scientific means of determining if a particular pressure is the use of a pyrometer to assess whether the rubber has reached the manufacturer's recommended temperature, charting the pressure increase of a tire after track sessions will give a good impression of how hard a tire is working.

Stamped on the outside of many of your tires is a recommended tire pressure range. (At least an upper limit.) For longest tire life it is my recommendation that you strive to keep them at the higher limit of those recommendations (regardless of what your motorcycle owner's manual might say to the contrary.) Further, this pressure should be determined while the tires are cold - meaning, have not been used for a couple of hours.

Start with the bike manufacturer's recommendation in the owners manual or under-seat sticker. This is the number they consider to be the best balance between handling, grip and tire wear. Further, if you're running alloy wheels on poor pavement, consider adding 2 psi to the recommended tire pressure just to reduce the likelihood of pothole damage. Just as you would for a car, increase the pressure 2 psi or so for sustained high speed operation (or 2-up riding) to reduce rolling friction, increase tire life, and casing flexing.

In order to get optimum handling a tire has to get to its optimum temperature, which is different for each brand of tire and different uses. Most of us don't have the equipment needed to measure tire temperature directly so we measure it indirectly by checking tire pressure since tire pressure increases with tire temperature. Tire temperature is important to know because too much flexing of the casing of an under-inflated tire for a given riding style and road will result in overheating resulting in less than optimum grip. Over-pressurizing a tire will reduce casing flexing and prevent the tire from getting up to the optimum operating temperature and performance again suffers.

The tire is all speculation until you rule out everything else. It should be easy to narrow it down since it didn't do this before you replaced some parts.

I've gone over the bike, and granted, I might have missed something, with the service record (previous owner didn't mind tossing money at it) all "seemed" ok, anything questionable, I replaced.
Not sure if mentioned but new dunlop D404's on front and rear.

ok, I'm OCD.
under seat says 28, on the advice of a few, added 2psi for the rim style. 30 psi Felt like crap.
Ran 32 psi and that started the thread here. Based on what I read, my own experience, I was worried about running more than 6-8 pounds past what the seat sticker/manual said.

This morning ran 34 and it lost a lot of the problems, tire temp after half an hour riding from cold in shade to step off, grab laser temp thing was less than 3%
I slowly rolled around a parking lot at 2-5mph and there was still a tad of that mushtire feeling, but much, much better.

So, a bit ago, I bumped tire temp cold to 36, just ran 30 minutes and..the tire fairy must have sprinkled some dust.
Temps 3% increase- maybe a tad more, my public school math education is showing thru, tire pressure after run was 39, I believe based on that I can run 38 pounds cold. I'll test that much later today. But I suspect with everyones help here, the end game- the final culprit was not as much as the brand/model tire, but the pressures.

edit: one thing I will do is pull the front tire, pop the tire off and check/mark rim balance, then mount tire and rebalance. I do not care for the lump of weight on one side of the rim- in the past my boss would give me crap for not breaking the bead, and moving the tire 180' and rebalance it.

The information from Dunlop mitigates against the front end low speed instability being related to the newly fitted 404's.

Are tubes also fitted?

Any anti-flat product such as Gorilla Snot being used inside the tires?

Is a rim lock installed?

Any visually obvious fitment issues where the tire beads meet the rims?
(Maybe the tire wasn't popped fully onto the rim when it was installed.)

Just shot-gunning.

Good Fortune!

Patton wrote: The information from Dunlop mitigates against the front end low speed instability being related to the newly fitted 404's.

Are tubes also fitted? No

Any anti-flat product such as Gorilla Snot being used inside the tires? No.

Is a rim lock installed? No idea, I'd guess not based on the factory 'mag' wheels.

Any visually obvious fitment issues where the tire beads meet the rims?
(Maybe the tire wasn't popped fully onto the rim when it was installed.) Interesting.. I had looked earlier, but not on the stands with the higher pressures in- those might magnify that

Just shot-gunning.

Good Fortune!

I'm currently running 8# more psi than the seat suggests, and intend on running 10. Never would have tried that on my own.
The last run there is a slow sweeping tight turn to the right that climbs up after it hits bottom at the apex of the curve, its always been crappy feeling in that particular turn- my control test if you will. HUGE improvement with 8.
And thus, I'll mess with the back as well. I'm running 38 in those now, will bump them up two.
chicken strips looked ok.

Im pretty sure tire pressures listed as max inflation on sidewalls are for cold temps. They know pressure will go up once ridden. My Bagger calls out recommended inflation cold for Dunlops at 36 front and 40 rear Based on normal loading so you should be fine. I bet with the air you added the bike feels like a different animal.

Street Fighter LTD wrote: Im pretty sure tire pressures listed as max inflation on sidewalls are for cold temps. I bet with the air you added the bike feels like a different animal.

Correct. Excellent read and deserves its own thread.
aprilia.rsvmille.home.comcast.net/~april...suspension_guide.htm
click "suspension guide" if that link goes to home page


Yes, its starting to feel more like the Superbike its supposed to be.
The rest of the work needed is absolutely minor-squeaking rear brake when applied, exhaust leak I can't track down, odd oil leak somewhere between the two carbs, suspected spot, probably old dead o rin, otherwise, its gettin' fun!

Oil leak between carbs, most likely the o-rings at the Oil switch housing. There are three o-rings there.

Very interesting.
Had it out today for about an hour an a half, mix of mostly highway 60-65 and two lane county types 45-55
It is a different bike.
Both tires are ONE pound under max sidewall pressure- neither gained more than 10% heat increase.
They do NOT feel as sticky in turns, but..hey, you've seen the bike, its got 200 pounds of extra crap that doesn't really belong on a lemans course bike.
The really painful 0-5mph turning, starting stopping is almost like the other bikes I've had in the past, and I suspect I'll replace the rear swing arm bushing(s) with something fancy like that neowhatever instead of OEM.
This is the first bike I've ever owned that truly needed everything near max- front fork air max, rear shock air at max, front and rear tires almost at max. rebound setting one down from max. ALL the other bikes were always down at the starting pressures, or what someone suggested worked fine. this one...demanded much much more

If someone finds this however many months down the interweb road in a search, do read that article about tire pressures (couple of posts up) and simply going off what someone says isn't going to cut it. Takes a couple of hours at most to find the exact pressure correct for YOUR bike and YOUR tires.
Underseat numbers are only a starting point, not a set in stone PSI number.
BTW, that rebound thing I did in the first few posts, its what its felt like in the past- bump the end bar, it goes out, comes back settles instantly. The tires were too low, probably dangerously low. Whew.

much comps go out to those who tossed in their two bits

regards, CWG

Ride it like you stole it Some hard seat time and that rebound thing will feel just right. I to think the tires might be the issue with the fairing as unsprung weight