Tires

[fuel80guy]

Can anyone tell me if there is 16" radials made for our beloved fj's?

[FJ1100mjk]

For 16" tire choices and opinions on them, use the search function of this website. This topic has been covered a few times, and was done again just recently.

[jscgdunn]

Avons only so far as I understand.  Use a 110 on front rather than 120.

[FJmonkey]

Yes, I ran on Avon AV45/46 when I had 16" front and rear. The Pirrelli Sport Demon also seem like a good choice as well even though they are not radial.  

[fuel80guy]

Okay great I have 2 85,s and im converting one to 17" and the other I may keep with 16"

[andyoutandabout]

I liked the 16'' avon azaros as mentioned by Monkey. Now i'm on 17s, I favor michelin pilot road 3s - they are the best tire I've ever had.
Andy

[Mick1164]

The original FJ rims are not the right width to run radial tyres, just saying. I'm running Avon Roadrider crossplys and find them to be excellent. Metzeler Lasertec and Pirelli Sport Demon are also a good choice in crossply.

[fintip]

People on the UK owners club tend to believe radials on the FJ are a bad idea. Everyone else in the world thinks they are nuts! (No offense, but...)

fjowners.wikidot.com/tires

[FJ_Hooligan]

The original FJ rims are not the right width to run radial tyres, just saying.

What has the width of the rim got to do with a radial tire? (answer is NOTHING)

If they make a radial tire that matches the FJ rim width then it can be used.

For those that believe the FJ wasn't "designed" to use radials, what specifically would they need to change to be radial compatible? (answer again is NOTHING!)

[Mick1164]

The original FJ rims are not the right width to run radial tyres, just saying.

What has the width of the rim got to do with a radial tire? (answer is NOTHING)

If they make a radial tire that matches the FJ rim width then it can be used.

For those that believe the FJ wasn't "designed" to use radials, what specifically would they need to change to be radial compatible? (answer again is NOTHING!)

Yes I am a member of the UK Owners Club and in my ignorance I read this and followed the advice, ie junk the radials my FJ came with and fit Avon Roadrider crossplys, which I personally find better.

This is from The Doc at the FJ Club.

All FJ's were designed in the 80's, and in this period
all motorcycles came with crossply tyres.
The crossply, due to its construction is fitted (by modern
standards) to thin rims, in the FJ's case the front
is only 3" (inch) wide and the rear 3.5" wide.
To support the weight the crossply tyre its manufacture
has to be very strong in its side walls, this stops
flexing which would lead to instabilities and poor grip
if unsupported.
In 1987, Michelin introduce
the first radial tyre for a
road motorcycle, the Michelin
A59 X and M59 X. These
tyres were designed for
wide rims, the side walls
were both thinner and
lighter in construction. The
advantage of this was
cooler running and better
mileage for the same
thread compound used in
the Crossply.
Our problem is, if we fit
these Radials to the thin FJ
wheel rims, none of the advantages
can be transferred
to our bike because
the rims are not wide
enough to allow the radial
tyre to work in a way it was
designed.
Yamaha, or any of the tyre
producers have never tested
a radial tyre on a FJ. Tyre manufacture companies list
what would appear to be the correct size, but this is
not the same as actually testing them. A front radial is
designed for a 3.5" rim and the rear for a 4" rim.
The result of fitting radial tyres to wheels designed
for crossply tyres is two fold.
1) The front 120/70zr17 is designed to fit a normal
modern 3.5" front wheel, but when fitted to wheels of
the 88-95 model bikes the front tyre distorts making
the tyre look thin. Because it has been squeezed into
a 3" rim and this alters the profile of the tread and consequently
the contact patch with the road.
The result when riding the bike, it causes the front end
to feel light which also makes it drop into slow corners,
plus it can make the front end wobble.
2) The rear will wear very square (like a side car tyre),
it will be feel fine when new, but once it starts to wear
you will a notice flat part in the centre of the tyre tread
and also a step as it goes to the edge of tyre.
Not only does it look wrong it will certainly effect the
handling.
And for all you 'doubting Thomas' out there,
below is an article written by the performance
guru Kevin Cameron of Cycle World.
"Quote"
Tires on Bikes Not
Originally Fitted With
Them.
As with cars, the official
line is no radials for
bikes originally biasequipped,
and definitely
no mix-match
......
Bias tires were normally
cantilevered out
over a rim ignorantly
narrower than the tire;
radials must not be.
Particularly bad is
putting a radial on a
narrow rear wheel.
It does not matter how
much your mate down
at the pub says radials
work well on a FJ, because
they're great on
his Pan, you now know
he doesn't own a FJ so its unfair to take his opinion.
I often say "You wouldn't put Carl Fogarty's racing
tyres on a BSA expecting it to handle better"
You may have noticed that the clubs catalogue never
lists a radial tyre and hopefully by understanding the
above, you should have worked out why.
Please note;
The compound on a new crossply is not the same as
when it was manufactured in 1984. It now has the
same modern compounds that your friend has on his
latest Bridgestone 020 etc..., just the difference is in
the construction ie crossply / radial. So to sum up, it
will still have the same level of grip both dry and wet
weather as a radial.
Bikes are best left to how the manufacture designed
it, and if you want to fit modern radial tyres, then
please simply fit modern rims like a Yamaha FZR1000
Exup rear and Genesis front.

[aviationfred]

I believe for the most part, the majority of the members that use radial tires have the GSXR/FZR wheels installed on their FJ's.

For those that have OEM wheels. I can agree with the statement from Doc, that the early radials were not designed for the narrow FJ wheels.

The assumption is given that, to use the radials of the early 90's an owner HAD to use a wider tire (160/170 with a 60/70 sidewall), or the 120/60 front tire. I can agree with the pinched sidewalls and the premature squaring of the tire centers.

With the advancement in tire technology and a few manufacturers that have decided to make a radial that is an EXACT match to the FJ OEM tire sizes. I believe I would buy the AVON radials in the 110/16 front and the 150/16 rear and feel ultimately more confident of tire quality, grip, wet weather capability, feedback and mileage over bias ply tires that are still offered.

Fred

[fintip]

(I use Avon radials on my 16" rims. I would love to upgrade to modern rims one day, but for now, that's what's on there.)

I added it to the wiki, so Doc's side of the story is present.

But I would argue that this is likely why a 110 radial is advised, instead of the "120" we are supposedly advised.

"Our problem is, if we fit
these Radials to the thin FJ
wheel rims, none of the advantages
can be transferred
to our bike because
the rims are not wide
enough to allow the radial
tyre to work in a way it was
designed."

This is what the argument hinges on. Why not just use a narrower radial, which is exactly what we do?

"As with cars, the official
line is no radials for
bikes originally biasequipped,
and definitely
no mix-match"

Notice he makes sure to say "officially"?

The biggest neglect is that radials have thinner sidewalls precisely because they are DESIGNED to flex:

Some basic information on tyre construction in 'lay' terms.
'Cross-ply' ply tyres run 'hotter' than radial ply.
Cross-ply tyres have their carcass plys 'crossing' each other, ie, the plys are laid down, for want of a better term, so that each layer of plys crosses over the other, as in a criss-cross pattern. Radial plys run from bead to bead 'radially' and do not actually cross over each other, thereby allowing the trye to 'flex'. This flexing is what is referred to as "the slip angle".
You will notice that a radial tyre feels softer in the sidewall areas. This is due to the flex of the carcass, and allows the tyre more 'slip', thus more of the tread area is 'flatter' in contact with the ground when under load at different angles.
Imagine bracing a wall frame with cross-braces so that is retains its shape and position, and apply that thinking to a cross-ply tyre. If you pushed one side of the frame, it would most likely retain its shape and slide along in its intended shape.
Without the bracing, one could push the frame out of its preferred shape and it would move around and flex, now apply that to a radial tyre. Push on one side of the imaginary frame and it would be out of 'square'. The base would stay where it was and the top part would move across slightly.
Back to the tyres. Because the crossply is somewhat rigid in its construction and the plys cross over each other, more heat is generated which is the enemy of tyres.
A radial ply tyre creates less heat build-up, (less friction), which equals less wear.
Road grip. A cross-ply tyre, due to its sidewall rigidity, won't flex as well as a radial and will follow the rim rotation under load, whereas a radial, due to the more flexible sidewall, will flex equating to the tread lagging behind, thus creating a better grip on the road surface.
With the rigid frame, if you push the top of the frame the base will move with it, this would cause friction at the base and therefore heat. With the flexible frame, as you push the frame, the base wants to stay where it is and the top part will move back and forth. No movement of the base, no friction.
This ability to flex is evident on dragsters/rails, where one can see clearly how the tyre stretches outwards at speed, and as 'traction' increases, due to heat, you will notice the sidewall twisting 'out of shape'. That is, the tread lags behind the rim rotation slightly. This is the slip angle of the tyre. That action is extremely minimal with crossplys. Too much heat would be generated in this instance and traction is lost.
Bottom line. Radial tyres provide 'better' grip and wear longer than do crossply tyres.
The above summary barely touches the subject of tyre construction etc, because the applications are dependent of a myriad of factors, and I could rave on all day about tyres, if given the chance.
I would be happy to answer any questions on tyres, either in technical terms or lay.
Tread design is yet another subject altogether.
Sorry about the long-winded response, but you have hit on one of my favourite subjects.

In that same forum, they question this exact topic. The same guy who typed the above, adds this:

I've never heard of a motorcycle being specifically designed for radial tires. If you can find radial tires that fit your rims, I believe that they would always be the best choice.

Other than rim size, what would you possibly make different on a motorcycle to make it work better with radial tires or with bias ply tires?

And later

Okay, let's suppose that I'm building a custom bike from the parts catalog. Besides engine and transmission, I have to choose a frame, forks, rear shock(s) (assuming it isn't a hardtail), and braking components. You would think that the description for those would indicate whether they have been designed specifically for bias or radial tires. But I've never seen such an indication anywhere, ever.

I would still like to see something from a web site, magazine ad (or article) or from a book indicating that any one part has been designed specifically for one type of tire or another.

There are lots of references to rims being designed to use a tube-type or tubeless tire, but I've never seen anything for bias vs radial.

All I need is one reference.\

Later, much later, the thread is resurrected, and he DOES add this:

Since Proprioceptor was "kind enough" to resurrect this thread from nearly two years ago, I've acquired a little bit more knowledge about the difference between radial and bias ply tires. Specifically, when the Grand Prix racing motorcycles converted from bias ply tires to radials in the late 1980's, they found the need for stiffer frames, better forks, and stronger swingarms to deal with the additional traction. The suspension components and frames that worked well enough with bias ply tires twisted too much with the newer radial tires making the bikes much harder to ride. They also found that the tires no longer overheated after ten laps, so the tires kept their initial traction much longer - at least until the had worn off all of the good rubber.

None of this matters much if you never experience any serious cornering forces, though, since you won't be stressing your frame much cruising around at "safe speeds". But I still like riding modern motorcycles with radial tires much more than the older ones with bias ply tires. I have much more trust in the cornering traction of a radial tire.

But that has nothing to do with what Doc says, and I would argue that it actually proves his argument wrong! The only problem was you could ride so much harder with radials on the bike that you had to upgrade the rest of the bike to keep up!

Guess what some of the biggest mods we do here are? SUSPENSION UPGRADES! Likely because we're using better tires! On the other hand, the FJ is over-durable and isn't designed to be so lightweight that an increase in force somewhere will break it. Our frame is far stiffer than a modern bike, our swingarms are heavy lugs. Our forks ARE a weak spot, if we have one--so we now have a fork brace and cartridge emulators.

The 3" vs 3.5" measurement argument sounds totally bogus. 110/70R16 covers the relevant dimensions of the tire. If it fits, it fits--it just has a design that gives it better traction.

I have a lot of respect for Doc, but tires clearly are not his expertise.

[FJ_Hooligan]

20 years ago all that was true.  However, times have changed as well as tires.  What you cite is not a motorcycle design problem, it was a tire problem with the original radials.  There was not a big selection of radials when they first appeared.  There are NOW proper fitting radial tires for the FJ's stock rims.

Personally, I really didn't see a big difference when I mounted my first set of radial tires.  Due to bad planning on my part, I've had to use a few bias ply tires in a bind and they worked as well as the radials.  Hell, I've even ran radial front and bias rear at times.  Couldn't tell any difference from the seat.

[Bminder]

I'm so confused. 

[fintip]

I've run a radial/bias combo before. Definitely noticed a diving tendency when trying to corner hard. Not fun. Only did it because I was tight on money and the bias tire was free NOS.