RE Thunderbird - Rear end wobbling at 60kmph

[krimurali]

Let me share with you guys that I did have a taste of motorcycle touring on RE Thunderbird 2002 model. There was a friend's marriage at Ambur(on Chennai-Bangalore National Highway). Ambur is 200km away from Chennai. So did a total of 400+ km in the weekend. I have not taken any photographs since being my first trip, i concentrated more on reaching safe without any breakdowns on highway.

Nevertheless, Onward journey, I had a flat rear tyre and had to halt for almost two hours near Vellore.(150 km from Chennai). Otherwise cruised at 80kmph. Had it fixed by a mechanic who is not very well conversant with bullets.

Then on the way back to Chennai, had a wobbly feel on the rear end. The rear tyres was having some imbalance and the bike behaved as though the front tyres and rear are separate units. In that I travelled with pillion, my girlfriend and she too felt the movement. To be more precise, the wobble is not up and down jerk, it is like when i tilt the bike the front end tilts and then back end does not fall by that same angle. The frame did not give a rigid feeling and my confidence in cornering got affected. I suspected some kind of play in the swing arm, but do not know how to check it by myself. I had to reduce the speed to 60kmph but still had a wobbly feel. I also reduced the tyre pressure from 38 to 30psi on the rear(front remaining a constant 22psi) but no effect. Carefully rode and reached Chennai safely. Can you give some pointers what needs to be checked? I am really scared to take the bike for another touring... Please help...

Murali

[Mohsin]

First of all, congratulation for your recent trip, that is was makes RE owner  stands out from others.

Regarding wobbling, in your case there could be various reason but here I think as you had flat tyre, it could be something like imbalanced tyre due to improper fiting as we see in cars, sometimes while getting flat tyre repaired, there is issue of tube not properly settled at center (mechanic calls it "Center out" problem) . Also the level of wobbling you mentioned strengthen the fact that its not properly settled tube inside the tyre.

You may take out all air from tyre and refill if after tapping tyre firmly at all various places and see if it helps.

Beside, you suspect it could be swing arm at fault, we you can test it  yourself, when on center stand, check if rear wheel is firm or by checking it yourself.