new tires on paso

discussions specific to the 750 Paso

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persempre907
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Re: tires on paso

Post by persempre907 »

JWilliam wrote:Now about that 140/70, what sort of failure do we think can happen due to the wrong specification? Deformation of radius? Rapid and uneven wear? Exposure of the carcass due to minor rips in the rubber?
I think the worst problem is the fitting on a wrong rim.
So, besides the wrong specification, the tire doesn't work as it should.
I guess that all in all is a bad combo.
Really, it looks good but...
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paso750
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Re: new tires on paso

Post by paso750 »

The higher the load the more the tire will heat up. Specially in combination with a lower tire pressure (0,4-0,5bar is already enough) this can lead to a damage in the tire fabric. There won`t be any signs of that which can be seen. But in the longrun or on long rides this can lead to the thread pattern to come off and/or the tire to blow out. Wear is probably also higher. Problems can already occur if the weight of the vehicle corresponds with the tires LI index and are more likely if you exceed it.
One should be aware of this and ride accordingly if you choose such tires no matter if there is still some safety buffer.
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randtcastell
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Re: new tires on paso

Post by randtcastell »

I checked on the tires to verify their load ratings anf their model numbers just to make sure they were both accurately reported in this thread and the results are:

front is: Michelin Pilot Sport 120/70 16 MC 57 H max load 230 kg/507 lbs
rear is: Pirelli Diablo 140/70 16 MC 65 P max load 290 kg/639 lbs

Thank you again all for your comments and feedback.
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Re: new tires on paso

Post by redchubeka »

why you did not consider this: SPORT DEMON 150 70 16 68S for the rear rim?

it's a little bit larger...

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Re: new tires on paso

Post by randtcastell »

That tire is, in my experience, unavailable through any retailer in the U.S. or at least I've never been able to find it. I am unable to find that size available in any tire. It is an intriguing size though...

Thanks for you thoughts! Best, Randy.
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Re: new tires on paso

Post by redchubeka »

the pirelli SPORT DEMON 150 70 16 68S in Italy is available for 80 €

I know that someone in Italy is using that tyre on paso rim
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Re: new tires on paso

Post by nnnnnnorman »

that sounds like a reasonably priced option. does it involve any mods to the bike at all?
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paso750
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Re: new tires on paso

Post by paso750 »

that one should fit w/o any mods. It`s also a scooter tire, recommended for 4.00x16" rims.
(speedindex S: 180km/h, Loadindex 68: 315kg).
It`s a very uncommon size that exists from Pirelli, Maxxis or Dunlop (D404 but I think these were discontinued)

For the ones who didn`t see it. For the P750 & 906 Ducati Germany recently issued a document of compliance for a 130/70+150/80 Avon tire combination. It will require lifting the front fender and probably a longer chain.
http://www.box.net/shared/gq6hrzi9s4
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Re: new tires on paso

Post by Pasorules »

Did you have to do anything to the chain or sprocket?
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Re: new tires on paso

Post by randtcastell »

Pasorules wrote:Did you have to do anything to the chain or sprocket?

If your asking me, regarding the 140/70 16 on my 5" Strada rear wheel, the answer is no. This option needs no modifications.

I've got 450 miles on the tire to date and I find no problems so far, just great handling and grip.
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Re: new tires on paso

Post by Pasorules »

Thanks. I just had my swing arm modified by Morgan Machine in SF. I installed a 160-80-16. The tire will work but I need to get a different rear sprocket--like a 38 tooth. I tried making the chain longer, but that didn't work. I think the solution is a smaller sprocket. By the way, I am looking for the large allen screws that fit the side body work to the fairing. I have two parts bikes but those screws are long gone. Thanks. Richard.
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Re: new tires on paso

Post by pasoist »

I installed a 150/80 rear tire on my 750. Only modifications I had to do were a longer chain (108 links instead of 106) in order to get the tire rear enough. (Otherwise the tire does not have enough room to rotate.)
And a larger rear sprocket (40 teeth instead of 38), in order to get the chain tight enough (with the 38 tooth sprocket there´s not enough adjustment range to tighten the chain).

Pretty simple anyways, didn´t have to do any irreversible changes to the bike.
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Re: new tires on paso

Post by paso750 »

I installed a 160-80-16. I think the solution is a smaller sprocket
I don´t think you`d really want to use a smaller sprocket if the wheel diameter is already bigger. For highway riding that may be fine but I doubt you will like it when riding in city traffic or on twisty roads.
Get a longer chain instead.
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Re: new tires on paso

Post by riascns »

Regarding how the tyre can fail, I had an experience with a z650 in France about a decade ago.

Went touring on a bike I had just purchased from a courier who was running it on cheap tyres.

cruising at about 150kph with a passenger and luggage the tyre staretd to delaminate (tread bulging and unsticking from the carcas). Eventually the bike would wobble (to the degree that I could not guide it at all) at anything above 30kph. Did the lakt few km below that speed to get back to the UK as I was a student with no money or no time to get a tyre in France.

At a guess I would say it is unlikely that you would have an instantaneous and catostrophic deflation, but the bike could become seriously unstable at speed which may result in a similar outcome.
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Re: new tires on paso

Post by pasoist »

drove to the tire dealers today and got a bridgestone 130/70-16" fitted on my Paso.

Had to remove the front fender for now, got to put some spacers and longer bolts so that the wheel has enough room to rotate. This I had suspected so no news to anyone.

BUT!

What I did not expect was that the tire contacts with the fairings at the bottom of the side fairings (you know the front-low edge right under the front cylinder) even in the smallest bumps or if you turn the wheel too much.

Has anyone else had the same problem?

As I recall, someone said on this forum that you would not have to mutilate (modify) the fairings when fitted a different then 130/60 tire.

so where did I go wrong?
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