Anyone fitted a 190 rear tyre to an FZ6?

Wolfman

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The other day i got told by my mechanic that i should fit a 190 rear tyre to my bike, to help raise the rear a bit more, as we have dropped the front forks through the triple clamps as far as we can, and have my rear shock jacked up as high as it will go, and i still want a more forward leaning stance on my bike....majority of riding is sport riding....

Qusetio is, has anyone here fitted a 190 rear, and if so, what has been youe experience with this?

Cheers, Wolf.

:thumbup:
 

Wolfman

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I would \"assume\" you will get some \"lift\" from a 190... depends on the aspect ratio and manufacturer. I can't see it adding up to anything huge though (which is a good thing). Maybe a couple mm at most.

Going for the 55 profile, not the 50 profile...and yes it will only be minor, but this coupled with the fact that my present rear is bald as a badger, i am expecting a generous improvement in terms of ride height from where it is presently at...cant jack up the ohlins further, without regassing shock, or using spacers...no ride height adjustment on my Ohlins shock.

Thanks for the input.

:thumbup:
 

poorwboy

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Going for the 55 profile, not the 50 profile...and yes it will only be minor, but this coupled with the fact that my present rear is bald as a badger, i am expecting a generous improvement in terms of ride height from where it is presently at...cant jack up the ohlins further, without regassing shock, or using spacers...no ride height adjustment on my Ohlins shock.

Thanks for the input.

:thumbup:

Do not do it, the tire will be flat across and in turn the bike will not turn. There is a member here who tried it and it doesn't work.
 

DefyInertia

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If you're looking for improved corning performance, this is not the way to go.

How do you have the front forks positioned in the triple? I'm confused by your first post.
 

Wolfman

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Do not do it, the tire will be flat across and in turn the bike will not turn. There is a member here who tried it and it doesn't work.

first of all,thanks for the input.am aware of potential problem re flattening but I live in a hilly area surrounded by winding roads, a high % of my riding in sport mode,and am on edge of tyre a lot...no chicken strips.also tyre is dual compound so is harder in the middle of the tyre, which should help combat the squaring off issue.
 

bmccrary

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I have a 190 now. Its not that bad.

IMG_2629.jpg


IMG_2624.jpg


IMG_2620.jpg


A bit harder to get that last part of the tire down...

-bryan
 

Hellgate

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So what are you trying to change, I'm not following? If you want to lean forward more why don't you try a lower bar, ie: FZ1 flat bar, clip-ons, etc. They will balance well with the rearsets. Pitching the whole bike forward will steepen the rake and shorten the trail, and if the forks are all the way up I'd think you could be in for some serious tank slappers at speed. Remember Yamaha designs and builds and entire package that can be tweaked a bit here and there, but if you make major changes you could really upset the whole balance of the bike.
 

DefyInertia

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So what are you trying to change, I'm not following? If you want to lean forward more why don't you try a lower bar, ie: FZ1 flat bar, clip-ons, etc. They will balance well with the rearsets. Pitching the whole bike forward will steepen the rake and shorten the trail, and if the forks are all the way up I'd think you could be in for some serious tank slappers at speed. Remember Yamaha designs and builds and entire package that can be tweaked a bit here and there, but if you make major changes you could really upset the whole balance of the bike.

+1

:confused:

And it's well established that fitting a 190 will not help you carve it up in the twisty bits.

I'm still unclear on how you have the forks positioned.
 

mstewar1

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So what are you trying to change, I'm not following? If you want to lean forward more why don't you try a lower bar, ie: FZ1 flat bar, clip-ons, etc. They will balance well with the rearsets. Pitching the whole bike forward will steepen the rake and shorten the trail, and if the forks are all the way up I'd think you could be in for some serious tank slappers at speed. Remember Yamaha designs and builds and entire package that can be tweaked a bit here and there, but if you make major changes you could really upset the whole balance of the bike.

+2

Like Defyinertia, I'm a little puzzled by why you've moved the forks in the clamps? Are you trying to get a "raked" (high a$$ end?) attitude from the bike? Is the fork positioning a quest for a particular aesthetic result or are you seeking a particular performance outcome? Are you wanting to quicken the steering? Because it sure sounds as if that's what you're going to get by moving the fork tubes up in/through the clamps. Plus, it seems as if moving the forks up through the clamps like that would also introduce a, likely unwanted, change in the lock-to-lock turning characteristics.

Perhaps a better route -- one that would allow you to maintain the as-designed ride characteristics -- might be to try the different (flatter) bars and perhaps a naked front(?)

Maybe I just need to go to bed...
 

Wolfman

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So what are you trying to change, I'm not following? If you want to lean forward more why don't you try a lower bar, ie: FZ1 flat bar, clip-ons, etc. They will balance well with the rearsets. Pitching the whole bike forward will steepen the rake and shorten the trail, and if the forks are all the way up I'd think you could be in for some serious tank slappers at speed. Remember Yamaha designs and builds and entire package that can be tweaked a bit here and there, but if you make major changes you could really upset the whole balance of the bike.

+1

:confused:

And it's well established that fitting a 190 will not help you carve it up in the twisty bits.

I'm still unclear on how you have the forks positioned.

+2

Like Defyinertia, I'm a little puzzled by why you've moved the forks in the clamps? Are you trying to get a \"raked\" (high a$$ end?) attitude from the bike? Is the fork positioning a quest for a particular aesthetic result or are you seeking a particular performance outcome? Are you wanting to quicken the steering? Because it sure sounds as if that's what you're going to get by moving the fork tubes up in/through the clamps. Plus, it seems as if moving the forks up through the clamps like that would also introduce a, likely unwanted, change in the lock-to-lock turning characteristics.

Perhaps a better route -- one that would allow you to maintain the as-designed ride characteristics -- might be to try the different (flatter) bars and perhaps a naked front(?)

Maybe I just need to go to bed...

Ok, first of all i have a naked front, Have done a full racetech rebuild on front forks, springs & emulators, have dropped the forks through the triple clamps 25mm, plus have fitted flat FZ1 style drag bars, and fitted lighter Wave discs to the front, and forks are set up very stiff. All this has acheived a much quicker steering bike, that drops into corners much quicker, and has also made the bike a lot more stable under brakes....and with lots less dive, and a more progressive feel.

Problem has been that we have had trouble getting the rear of the bike as stiff, rear shock reaches end of it's stroke way before the front, and as a result have been experiencing a bit of wallow, under power, out of corners, as well as the back pushing the front, so bike wants to sit up, and steer straight, when pushing hard.

Putting the bigger 190/55 has effectively raised the ride height by about 10mm.

I went for a quick blat with new tyre this morning, and the bike still tips into corners just as well, and at this point, changing direction, or flickability also seems to be better than it was, probably due to the fact that my old rear was as bald as, and had no tread depth left on it.

Will let people know how it all works, after my ride on Sunday of about 350km's of riding the twisties, etc.

:thumbup:
 

mstewar1

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Hmm. Ok, thanks for the clarifications, wolfman.

So I guess by dropping the front end through the clamps should have the resulting effect of reducing the amount of overall leverage that the front end has, can put on, the rear end. Does that make sense? I mean, if the forks were at their stock height in the clamps, the respective amount of leverage that they would impart from the front to the rear of the vehicle would be greater -- because it'd be like having a longer lever arm. Was this notion part of the rationale for dropping the forks, in addition to the quickness factor? Or were they dropped solely for changing the steering angle?

Though moving them through the clamps would change the force they're capable of exerting over or onto the rear, it would seem that the shorter lever would also get to the end of its effective range sooner. Perhaps that's an unintended consequence/factor?

I'm curious as to what your rear sag figure is? Is your spring rate/weight correct? If I understand shocks at all (and that's not saying much), Ohlins would create/spec a shock for our bike based upon the stock engineering -- it'd be the same length, eye to eye, and the same stroke so that it would work in concert with the swingarm dimensions and associated linkages.

Is it possible that the spring rate may be lower than what you may need, thus the blowing through its travel? Does the shock have adjustable compression pre-load? How hard/high do you have that set? Where in the range of adjustment is it? If the compression pre-load is set high (say on 8 out of a possible 10), then I'd begin to suspect a too soft spring.

Of course, I could just be talking out of my back end, too. At least I'm glad to hear that the 190 didn't have a detrimental effect on the handling.
 

Hellgate

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I'll be an ass, "F'in buy an R6 dude!" :Flip: "Why the F are you modding an FZ6???" sorry....

What if you reduced the preload on the fork a bit to balance with the rear shock?

I understand your question now, but I'm not convinced that a 190 will make much of a difference, I think it will slow your turn in quickness. Now if you a flat spotted rear tire a fresh tire will help. My new Pirellis were night and day from the stockers.

What are you static sag measurements? 25mm to 35mm? My goal is to keep them pretty much the same, front to rear, regardless of stiffness.

Finally, for me, I prefer a compliant suspension that will follow the bumps and not bounce off of it.

If you are really having problems with the rear you may just need to pony up for a new spring Wolfman?
 

mstewar1

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Um, yeah, what Hellgate said -- "buy an r6". Of course I'm jk, Wolfman. I know that part of the joy of owning a bike is the whole process of personalization. But hey, there comes a time...

But seriously, I'm thinking it has to do with spring rate. Are we certain that you got the correctly sized rear shock? Did you compare it to the stock unit when you installed it? If it's shorter, it's gonna do what you're experiencing...
 

Wolfman

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Once again guys, thanks for your input.

Lets get started, dont want an R6, if i did i would buy one. Have ridden Sportsbikes all my adult life till recently, but bought FZ6 with a few things in mind.

1. i have a bad back, shoulder (as a result of a rather nasty highside on my Ducati), and have bone spurs & arthritis in my neck - t4, t5, so riding a bike with an ultra aggressive "racing" stance is agony within half an hour of riding.....can ride the FZ6 all day without any discomfort...:D:D

2. I have a son who regularly rides pillion, and a Sportsbike is not the safest, or most comfortable option here.

3. I need to carry a fair bit of gear, on regular occasion.

4. I dont like fairing's, even my Ducati only has a bikini fairing.

5. I love the naked look!

So i bought the FZ6 as i still wanted a bike with a strong motor that could keep up with a lot of Sportsbikes in the Twisties...only problem is, Mr Yamaha obviously decided that FZ6 riders dont care about going around corners! So i set out to fix it myself.....

That's where we are at now.....

Ok, Sag rates for front and rear are 25mm respectively, Front & Rear shock spring weight is 9.5kg, which is a considerable increase over the 8kg spring on a OEM FZ6 shock. I weigh 108kg's :eek:, currently rear shock compression is set at about 80%, but rebound damping has been kept at about 60%.

Since my ride last weekend with a near bald trye....(was completely screwed after 400km's last weekend), and since i experienced such crappy handling on this ride due to the rear misbehaving...which was more pronounced than usual, as the mechanic did stiffen the front a little more at my request, when we changed forks last week!

Since this ride, i have decided to fix this problem, have upped the rebound damping by about 4 clicks, and fitted the taller, and surprisingly, much rounder profiled, stickier 190/55 piolt power 2ct (replacing a 180/55 pilot road 2ct).

As i said, i have only been for a quick blat, but immediately, bike feels much tighter in the rear, and in fact seems much quicker to tip in again......signs that the new back tyre has helped, and that more rebound, has settled things down a bit....if after my ride on Sunday, i am still having issues, i suppose there are a few things we can do, or conclude.

1. Maybe the front is too stiff?
2. Maybe the rear spring is not heavy enough, and i need to change to a heavier spring

Am thinking at this point that i may be close to sorting it out....other thing to consider is that i still have a Pilot Road 2ct on the front of the bike, and there is a small concern that with the rear having more grip than the front, that the rear tyre could also now push the front......have a Pilot Power 2ct front sitting on hold at the bike shop, just in case....

All i know is that i am having lots of fun learning about my bike, and how it behaves.

I am sure that by the end of this i will be able to get to the point where i can make finite adjustments on the go, centred around my many varied needs..such as different loads (Pillion, Pillion & Gear, Just Gear, Sport, Commuting) which was the point of it all to start with.

I love my Fizzer. :rockon:
 
W

wrightme43

LOL Hellgate has modded his bike probley more extensively than yours. LOL LOL


Ok
the 190 tire is to big for our wheel.
Look it up. The largest tire that will seat properly on our wheel is a 180/55R17. It pinches the tire, and makes the bead seat less than what it was designed for. You can do it, people have done it. Its just not a industry accepted best practice. Any failure will leave you in the wind, (and your dealer/mechanic who reccomended it) as the tire manufactur clearly states that this tire is not designed to fit the rim we have. Beyond that man, have at it.
5.5 inch wheel is what we have. Max tire size is 180/55R17
6.0 inch wheel size is required for 190 width tires.
 

Mississippi

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I have a pilot power 190/50 on my 07 because I had a flat on the stock back tire the second time I rode it. The only reason I have the 190 on the rear is because I bought the set used from a buddy for 100.00. I was really worried about the 190 after reading all of the comments about the safety of the tire on the bike, but for the price I could not pass it up. Now that I have it on the bike, I like it. It does seem to make the bike turn and corner easier, like my 08 ninja 250 did (first bike). I have only had the FZ for 3 weeks, and have put about 400 miles on it. I do not ride that aggressive as of yet, but I am trying to get better. The 190 did pick the bike up a little, but not a lot. I am 6'-7", so every little bit helps with the height. When it comes time to get a new set of tires, I will probably stay with the 190, because that is what I know and am comfortable with.
 

Mississippi

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A 190 will make the bike turn slower.

How does it make it turn slower? Isn't the tire more rounded from being squeezed onto a smaller rim? IMO it feels like it dips into the tuns easier which I thought was due to the tire being more rounded. Is it the pilot tire that makes it turn easier? If so, would the 180 of the same tire have similar effect?
 

Wolfman

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How does it make it turn slower? Isn't the tire more rounded from being squeezed onto a smaller rim? IMO it feels like it dips into the tuns easier which I thought was due to the tire being more rounded. Is it the pilot tire that makes it turn easier? If so, would the 180 of the same tire have similar effect?

Nice post.a 190/55 is taller,rounder and more flickable...which I found out first hand tonight over 130km's.rear end is also no longer wallowing!mission accomplished!by the way lots of r6 owners fit 190 gyres to a 5.5 inch rim and they have no problems.just cause manufacturer does not recommend it does not mean it does not work.
 
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