Wobbly rear end!!

[pdes]

This is a weird one - any advise gratefully received!

 

My RT is 5 months old and has covered 9000 miles. I run Conti Road Attacks and the rear tire has covered around 4000. Still loads of tread on the front and rear. Every so often, I notice what seems to be a rear wheel wobble. This occurs at no particular speed or riding style. It's is so prominent that a couple of times I have slowed right down but it vanishes as quickly as it started. I have inspected the rear end but all seems very secure. Any ideas what could be causing this as the legendary surefootedness of the RT is not working for me and confidence is taking a knock.

 

Do other riders feel this? Could it be that my Conti's need more air than the manual suggests or maybe it's a road surface issue that everyone notices!!

 

Thanks

[Tilly]

My Road Attacks were shot at that mileage. Changed to Michelin Pilot Road 2 and have had no problem since.

[pdes]

I wish my tyres were more worn so that I could justify some PR2s but there is plenty of meat left on them - and with 25k miles per year, I need to make them last!!

 

Anyway, i just looked at the Conti website and they recommend 6 psi higher in the front and back to the handbook. Would 6psi make much difference to the handling?

[tallman]

Yes, and get a tire tread measurement before deciding about tire life.

Frequently a tire "looks" good and has tread pattern, but is at or below replacement depth of tread when measured.

Best wishes.

[Albert]

Perhaps a wierd answer too but since you've got only 9000k on the bike, what did you migrate from? I mention this only because I noticed a difference with a full fared (or nearly so) bike when I got my RT. A small gust of wind can give the impression of some problem when it's just all the plastic catching some air. As for Conti's reccomendation, I'm on my second set of Road Attacks and I run closer to the BMW recommendations (40 rear, 38 front). My first rear lasted a little over 5k, the front more like 10k. I'm going to try a set of Road Smarts next. Good luck and don't ignore the problem.

[Boffin]

6 psi will make quite a lot of difference in handling. Of more importance it will reduce tyre wear, in particular with regard to squaring off and cupping.

The BMW handbook pressures increase with load simply becuase they are the lowest safe pressures for the load, selected to give the smoothest ride. I always go with tyre manufacturers figures, which nearly always equate to the 'fully-loaded' figure for the bike.

 

Andy

[pdes]

Perhaps a wierd answer too but since you've got only 9000k on the bike, what did you migrate from? I mention this only because I noticed a difference with a full fared

I wondered about the wind. I used to have a Suuzuki Bandit so I am quite used to a fairing but i have to admit that there has been some gusty wind about lately. If this was the problem though, I would not expect to get the "wobble" at low speed. Maybe it's a combination of gusty wind and 6psi less than recommended.

[Redbrick]

If none of the above solve the problem I would drain the final drive fluid and inspect it closely just to make sure something isn't self destructing in there...

[black99S]

I wondered about the wind. I used to have a Suuzuki Bandit so I am quite used to a fairing but i have to admit that there has been some gusty wind about lately. If this was the problem though, I would not expect to get the "wobble" at low speed. Maybe it's a combination of gusty wind and 6psi less than recommended.

I've run both new and worn Michelin Pilot Roads at 32F/36R and 36F/42R (155lb rider, stock screen, one up with light luggage) at all sorts of speeds and screen positions and still experience "nervousness" or "wandering" despite light hands, strong abs and tight knees when riding into gusting winds or when following cube vans or semis on-the-quarter.

 

Not everyone experiences this on their RT, and yes, a fully faired RT is a whole lot different than my R11S. In clean air the ride is perfect, and in filthy gusty rainy weather I appreciate the fairing more than I worry about the nervous handling.

[motoguy128]

The RT defnitely wander is strong winds, but no worse IMO than any other motorcycle I've owned. Actually, I think passing semi-s, It's less affected than the 2 sportbikes I owned before it.

[alimar]

in filthy gusty rainy weather I appreciate the fairing more than I worry about the nervous handling.

 

Bang on xactly...

[JustKrusen]

A loaded trunk and low tire pressure would aggrevate any wobble. I did not care for the trunk on my bike so I sold it. I'm on my second set of Contis' and I love 'em. 8000 out of the first rear and 14,000 out of the front.

 

[FrankBrown]

This sounds like you're describing exactly what happens when you ride over "tar snakes" on a hot sunny day, especially when leaned over???

[blkvelvt]

Exactly. Or white lining (lane sharing/splitting). My R12RT has PR2's and when I run along (Not across) painted lane lines, the old girls' rear end wiggles like granny doing the chicken dance at a wedding reception.

[pdes]

This sounds like you're describing exactly what happens when you ride over "tar snakes" on a hot sunny day, especially when leaned over???

Yep, I agree and I also get these effects but what I described has happened on a clear road and at low speeds (no snakes!). Just wondering if the roads have small ridges where they have worn but which are too small to notice as you pass over them.