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General Category => General Discussion => Topic started by: roortcloud on April 13, 2019, 06:02:59 PM



Title: Rear tire rub
Post by: roortcloud on April 13, 2019, 06:02:59 PM
After installing a new Michelin Road 5 size 180/55-17 and adjusting the preload of the rear shock I took my bike for a ride.
Sure enough, the  blue painter tape shows rubbing from the rear tire on both sides of the mud guard.
In my previous post regarding this issue I mentioned that I had a shock bolt failure that may have contributed to the issue. That obviously was not a factor.
Not sure how many members have a 89 or 90 & are running the same size tire. I would like to hear from you.
Maybe these 2 years are different enough to be "special"


Title: Re: Rear tire rub
Post by: Pat Conlon on April 13, 2019, 06:52:32 PM
Nope, it’s the tire. The Road 5’s have a wider shoulder than the earlier Road 4’s and 3’s.
I’m getting a tire rub on my hugger that I have never had with any other 180/55-17’s

Oh well, the bad news is they rub, get used to it because these bastards wear like iron. I bet I’ll get 8k miles out of my back tire. On a 1380 that’s saying something.


Title: Re: Rear tire rub
Post by: aviationfred on April 13, 2019, 06:55:43 PM
Are you using the OEM dog bones? What shock do you have installed?

I encounter the same problem on my 89 when I installed a BMW K1200RS shock. It only happened when riding 2 up. I installed the RPM shock and made shorter dog bones. Using Continental Conti Motion 180/55/17 tires. Never had the problem again.

On my 95, I have a set of Soupy's adjustable dog bones with a CBR600F4I shock and a FZ1 swing arm with a Dunlop Roadsmart 2 180/55/17 tire. No rubbing has showed.


Fred


Title: Re: Rear tire rub
Post by: roortcloud on April 14, 2019, 10:00:08 AM
To answer your question Fred. The dog bones are not original. I made them and used numbers recommended on this forum. The hole spacing is 4.527" center to center. Stock is 4.160" & I have a RPM rear shock.
As far as tires are concerned, I experienced the same rubbing with a Michelin Pilot 3. 


Title: Re: Rear tire rub
Post by: fj1289 on April 14, 2019, 11:32:01 AM
To answer your question Fred. The dog bones are not original. I made them and used numbers recommended on this forum. The hole spacing is 4.527" center to center. Stock is 4.160" & I have a RPM rear shock.
As far as tires are concerned, I experienced the same rubbing with a Michelin Pilot 3. 


Shorter links (dog bones) are generally installed on the FJ in order to raise the rear ride height.  If you have  actually installed longer dog bones then you have lowered the rear -  that would be the cause of the rubbing!


Title: Re: Rear tire rub
Post by: racerrad8 on April 14, 2019, 02:22:48 PM
Shorter links (dog bones) are generally installed on the FJ in order to raise the rear ride height.  If you have  actually installed longer dog bones then you have lowered the rear -  that would be the cause of the rubbing!

Not on the 89-90's that use the RPM shock which is a little longer than stock. The shock raises the rear and you have to lengthen the links to lower it back down.

That's where we have to work on Ron's bike.

Randy - RPM


Title: Re: Rear tire rub
Post by: GS Jockey on April 15, 2019, 08:55:47 AM
Shorter links (dog bones) are generally installed on the FJ in order to raise the rear ride height.  If you have  actually installed longer dog bones then you have lowered the rear -  that would be the cause of the rubbing!

Not on the 89-90's that use the RPM shock which is a little longer than stock. The shock raises the rear and you have to lengthen the links to lower it back down.

That's where we have to work on Ron's bike.

Randy - RPM

Yep, that's what I found with mine, but bloody hell the steering was quick... :wacko2: :wacko2:


Title: Re: Rear tire rub
Post by: fj1289 on April 22, 2019, 07:13:44 PM
Shorter links (dog bones) are generally installed on the FJ in order to raise the rear ride height.  If you have  actually installed longer dog bones then you have lowered the rear -  that would be the cause of the rubbing!

Not on the 89-90's that use the RPM shock which is a little longer than stock. The shock raises the rear and you have to lengthen the links to lower it back down.

That's where we have to work on Ron's bike.

Randy - RPM

Once again - open mouth and learn something new!


Title: Re: Rear tire rub
Post by: Millietant on April 24, 2019, 06:36:49 AM
Are you using the OEM dog bones? What shock do you have installed?

I encounter the same problem on my 89 when I installed a BMW K1200RS shock. It only happened when riding 2 up. I installed the RPM shock and made shorter dog bones. Using Continental Conti Motion 180/55/17 tires. Never had the problem again.

On my 95, I have a set of Soupy's adjustable dog bones with a CBR600F4I shock and a FZ1 swing arm with a Dunlop Roadsmart 2 180/55/17 tire. No rubbing has showed.


Fred

Hey Fred - I've just been reading some horror stories about failures in Soupy's adjustable dog bones, over on another forum - most seem to be blamed on stress fractures from poor design, rather than a manufacturing defect -not sure if yours are the same, or even if worry is warranted (don't know how true/accurate the accounts/tales are), but if you hadn't heard about this it might be worth checking out.


Title: Re: Rear tire rub
Post by: racerrad8 on April 24, 2019, 09:35:24 AM
On my 95, I have a set of Soupy's adjustable dog bones with a CBR600F4I shock and a FZ1 swing arm with a Dunlop Roadsmart 2 180/55/17 tire. No rubbing has showed.
Fred

Hey Fred - I've just been reading some horror stories about failures in Soupy's adjustable dog bones, over on another forum - most seem to be blamed on stress fractures from poor design, rather than a manufacturing defect -not sure if yours are the same, or even if worry is warranted (don't know how true/accurate the accounts/tales are), but if you hadn't heard about this it might be worth checking out.


The Soupy's design for the FJ is proven dependable. There are many, many sets in use with at least one set that I have experience with, having well over 100,000 miles on them. The FJ uses the factory bearing to pivot the swing arm linkage.

Of all of the failures I have observed with Soupy's links where all spherical ball end joint failures. The rod end appears to be not the proper design/size/type for this type of application. Here is one on Tim's FJ with R1 conversion that failed, it clearly was the rod end that failed: http://www.fjowners.com/index.php?topic=3148.msg160029#msg160029 (http://www.fjowners.com/index.php?topic=3148.msg160029#msg160029)

Randy - RPM



Title: Re: Rear tire rub
Post by: Millietant on April 24, 2019, 10:05:45 AM
That's good news then Randy  :good2: - I won't worry for Fred.


Title: Re: Rear tire rub
Post by: racerrad8 on April 24, 2019, 11:33:04 AM
The Soupy's design for the FJ is proven dependable.

There are many, many sets in use with at least one set that I have experience with, having well over 100,000 200,000 miles on them.

Randy - RPM

I stand corrected...

Randy - RPM


Title: Re: Rear tire rub
Post by: Pat Conlon on April 24, 2019, 11:40:07 PM
I have 60k on my Soupy bones, no problems *if* you set each side precisely the same.
Ask me how I know. The Soupy bones were fine, the swing arm bearings, not so much.
Lesson learned.


Title: Re: Rear tire rub
Post by: aviationfred on April 25, 2019, 12:20:49 AM
Are you using the OEM dog bones? What shock do you have installed?

I encounter the same problem on my 89 when I installed a BMW K1200RS shock. It only happened when riding 2 up. I installed the RPM shock and made shorter dog bones. Using Continental Conti Motion 180/55/17 tires. Never had the problem again.

On my 95, I have a set of Soupy's adjustable dog bones with a CBR600F4I shock and a FZ1 swing arm with a Dunlop Roadsmart 2 180/55/17 tire. No rubbing has showed.


Fred

Hey Fred - I've just been reading some horror stories about failures in Soupy's adjustable dog bones, over on another forum - most seem to be blamed on stress fractures from poor design, rather than a manufacturing defect -not sure if yours are the same, or even if worry is warranted (don't know how true/accurate the accounts/tales are), but if you hadn't heard about this it might be worth checking out.

The take away that I get from the Soupy's dog bone failure on Tim's FJ was the fact that only 1 dog bone was used. I would think that Soupy's engineered the dog bones to be used as a set of 2. The weight and stress on the single dog bone may have just been too much.


Fred


Title: Re: Rear tire rub
Post by: racerrad8 on April 25, 2019, 10:00:17 AM
The take away that I get from the Soupy's dog bone failure on Tim's FJ was the fact that only 1 dog bone was used. I would think that Soupy's engineered the dog bones to be used as a set of 2. The weight and stress on the single dog bone may have just been too much.

Fred

Fred, almost all late model sport bike suspensions use the single dog bone design. That is why I believe you read about failures on other bikes, but not the FJ.

Randy - RPM


Title: Re: Rear tire rub
Post by: Firehawk068 on April 25, 2019, 08:56:13 PM
I'm not sure how many miles I have on the Soupy's Bones on my '90, but they have a lot of miles on them.
I even chucked/tumbled the bike down the road with them. No issues with the Soupy's dog-bones.
They are plenty strong for the FJ.