Rear end is fish tailing in hard left hand turns

[ruger44]

More than once during a hard left turn my rear tire will fishtail for a split second. It always comes back inline but it kind of makes me gun shy on laying into the turns.

It seems to be always leaning left when this happens.
The bike is a FXRS-SP with Avon Venoms 140 rear 19" 90 front.
The bike tracks true and handles excellent with this one exception.
What should I look at to try and find out what may be causing this.

I am running 40# air in the rear tire could this be one of my problems; the wife goes with me a lot so I just keep it at 40#

IMO
I like the venoms on hot roads but they do not do well on wet roads here, I had the front end slide a couple feet with no warning in an intersection scared the hell out of the other 2 guys ridding with me.
A friend told me that his bike did this with Avon’s have any of you guys run these tires and what do you think about them.

[ruger44]

Maybe this is what I am experencing, I found this on another forum.

FL is the same frame as the fxr correct

"When an FL is banking though a turn, the normal lateral forces of cornering try to push the rear wheel out of line with the front. On other motorcycles, the swingarm pivot is solidly mounted, thereby preventing any significant lateral rear-wheel movement. But on an FL, the rubber swingarm-pivot bushings will easily deform under such loads."

[PROFX]

Originally Posted by ruger44

Maybe this is what I am experencing, I found this on another forum.

FL is the same frame as the fxr correct

"When an FL is banking though a turn, the normal lateral forces of cornering try to push the rear wheel out of line with the front. On other motorcycles, the swingarm pivot is solidly mounted, thereby preventing any significant lateral rear-wheel movement. But on an FL, the rubber swingarm-pivot bushings will easily deform under such loads."

FL, FXR same problem in the swingarm bushings. Kits are available to support the swingarm using solid style bushings. I'm getting ready to replace my swingarm bushings in my 97 FLHTC & 90 FXR that have the same handling issues. The product is called STA-BO, about $200 for the kit. They have a website. Heard nothing but good results from those who have done the converion. There is another kit available from Custom Cycle Engineering. It's more expensive ($350) than the STA-BO kit and I don't know anybody that has used their product. Good luck.
PROFX

[11963]

besides the swing arm pivots check yer rear tire dont have a pronounced transition from center flat section to shoulder( high milege wear) can cause a high speed/lean wobble. ride hard cb

[ruger44]

thanks "PROFX" for the info, I will look into the bushing replacements. Is there a way to check the bushings on the bike, has 25000 miles on it but it is 14years old. Could the bushing be degenerating from age?
"ELB" I will have a closer look at the tire wear pattern but the tire only has a couple 1000 miles on it.
How about the Avons any opinions?

[PROFX]

Originally Posted by ruger44

thanks "PROFX" for the info, I will look into the bushing replacements. Is there a way to check the bushings on the bike, has 25000 miles on it but it is 14years old. Could the bushing be degenerating from age?
"ELB" I will have a closer look at the tire wear pattern but the tire only has a couple 1000 miles on it.
How about the Avons any opinions?

It's somewhat hard to do unless you have a solid surface to strap the bike down onto. Because you will need to attempt to apply pressure to the swing arm by way of the wheel while it's off the ground. Obviously if the bike is not strapped down solid you'll have trouble getting a true feel for any bushing error. You'll want to push & pull the wheel in every direction possible in order to pick up any bushing errors.

The life of the bushing is an open topic. I've heard some have bikes with 100K miles and still the original bushings, and then some with far less mileage and worn out bushings. Chemicals from cleaning, road dirt, heat and a host of other things will effect the life of the bushings.

As For Tires:
Avon Roadranger & Roadrunner series are great, but I'll never buy another set of Avon Venoms. They are the worst tires I've ever owned for tracking in road grooves, pavement cracks, graded bridges, etc.
PROFX

[11963]

avons,,,I love em only tire I run ,,on 4th set now,at 1k ya should have no issues w/tire profile I get 10/11k on a set fxstb. ride hard cb

[ruger44]

OK I have checked the swing arm, the front axle free play and all is good,
I did find a new oil leak at the rear cylinder rocker box, bolt was finger tight. It looks like it was droping oil in front of the rear tire (left side) not a lot but there was oil on the frame. I also think that the left shock is shot and I have a pair of Works coming. I can feel it wallow on the left side doing tight slow turns. After cleaning the bike and scrubbing the rear tire it seems better now and hopfully with the Works shocks it will be even better.
Thanks for the help guys!