Thunderbird 900 handling - rear end - help !

[rumplebeartrebor]

Took it out for first ride this year but rear end now feels like its weaving when leaning into bends but ok when stood up. Wandering if its likely to be the shock or something with the swing arm or both ! Welcome any advice.

 

[otherwise]

First thing is to have a good look at the tyres front and back, particularly the pressure.
Elementary stuff but we don't know your starting point, even some very experienced riders can miss simple things while looking for complicated answers.

 

[rumplebeartrebor]

Thanks - back is relatively new running at 40 with a pillion front is ok at 36 - bike has just passed mot. From inspection on the centre stand cant feel any play in back wheel.

 

[otherwise]

first ride this year but rear

You say first ride, was it handling OK on the last ride before winter?
I often find when I haven't ridden one of my bikes for a long time the first couple of miles can feel strange. My mind starts to think too hard as to what may be going on. Then after a short time usually at the end of that ride or on the next I re-adapt and all's good.

 

[keystiger]

Hate to throw it out there, but rear wheel bearings?

 

[The Seeker]

No fluids could happen to be finding their way in front of that rear tire by any chance?

Has the swingarm been greased?

Posted with TapaTalk

 

[Mad On Triumphs]

Not wishing to offend you, but do you know how to do the basic checks for the MOT, if you do, you might want to check the spoke tension,( Make sure that when you hit the spokes with a spanner, that they all sound the same tone. Check the rear wheel alignment, have a look at your wheel rims too, make sure it's not cracked or has a slight warp on it. ( Has your T Bird got the eccentric adjusts or the screw and locking nut ) check the rear shock for oil leaks, the shock should return to the normal position ( if you compress the back end ) with no hint of delay. As has been said here, the wheel bearings are a good one to go for, also the swing arm bearings, check for play. Again as has already been said make sure that you grease everything up, get yourself a good quality grease gun, it will pay for itself in the long run
I have Avons on my 95 Thunderbird 900 and I run 36 front 42 rear, this came direct from Avon tyres. Whilst your in the general area, it wouldn't hurt to check that every thing is all torqued up ok. If you don't know how to check for any of the above, I'm sure that you'll get a wealth of helpful advice here. Just as an outside chance check your front fork seals aren't leaking
Keep us informed of your progress
Good Luck

 

[rumplebeartrebor]

Thanks guys - will follow this all up at the Weekend and let you know how I get on.

 

[otherwise]

I'll ask the question again, "was it handling OK on the last ride before winter"?
I think the answer could be important in getting to the bottom of your problem.

Another question, has anyone been mucking around or working on it since last ride before winter?

 

[harper6t]

Has anyone mentioned steering head bearings? always worth checking.

 

[avion]

You didn't perhaps spill anything on the tyre while it was stored?

...

Posted via ripped tapatalk.

 

[rumplebeartrebor]

Thanks its been garaged since December and was fine then. Front feels ok - definitely movement on the back and pillion felt the same. No obvious sine of any damage to tyres or rims and no sign of fluids leaking from anywhere. On the centre stand I can't feel lateral movement on the rear wheel. Don't know how I check the swing arm !? Plan is to take it out over the weekend and follow advice on checks and try to track it down. Thanks again

 

[avion]

You can check the swingarm by unloading the rear shock, by using the centre stand.

Sit on the floor next to the bike put one foot on the frame or motor, one hand on the frame to steady it.
Now grab the back of the swingarm near the rear wheel and shake like mad. Really pull and push.

You should not feel or hear any movement.

Now stand up behind the bike and try lift the rear wheel by grabbing the rim. Just enough to lift the wheel and swingarm weight, not to lift the bike off the stand. This will check the play in the rear shock/s bushes /bearings. You should detect very little to no play.

While you're at it and you've got another pair of hands, get the front wheel off the ground and check headstock bearings.

Sit spread eagle on the floor with the front wheel between your legs, grab the bottom of the forks and pull push again. Put it a bit of effort again.
There should be no play.

hth

...

Posted via ripped tapatalk.

 

[The Seeker]

I was riding one night where the rear-end felt like it was on ice at any speed over 55 mph. Under that speed it was fine.

At night on a dark road I couldn't see a problem.

Long story short.....it turned out to be a carb float sticking and dumping fuel onto the rear tire. Below 55 mph it didn't get blown back onto the tire. At a stand still it would quit and you couldn't see any sign of the leak since gasoline evaporates quickly.

 

[rumplebeartrebor]

Hi - Have checked out the swing arm and can't feel any play or hear any movement. Same with rear wheel. Cant feel any play on the shock. the tyres look ok and cant see any sign of anything spilt on it and no sign of any leaking fluids. hoping its just as "otherwise" posted - just getting used to the feel of it after the winter break !! Am running it out tomorrow.

 

[CarlS]

Keep us posted.

 

[The Seeker]

Just a puzzling problem???

Just throwing this out there blindly......

Spin the rear wheel manually and see if there's any noises. A brake maybe hanging-up, a warped rotor, sticking caliper after braking into a corner??

And see if your chain has developed any rigid sections.

Posted with TapaTalk

 

[rumplebeartrebor]

Hi - had the time to take it out for a good run this morning and it rode really well so all good but cant really explain what caused the problem !- I did give the chain a good lube so don't know if that could have been affecting the ride? Anyway - thanks again for all the advice. The inspection did reveal some wear on the lower part of the rubber / plastic chain guide / slide - I have seen some other posts about the problems in replacing this - anyone found a straight forward way of doing this?

 

[otherwise]

Good news.
Looks like it may have been similar to my comment from post #4.
I sure hope so, it happens to me a lot.

 

[CarlS]

I'm glad nothing major was wrong.