I own a 1991 TR Magna and i am having shaking problems around 40 - 60 km's then goes normal again. Any body have any idea why ? I have had it balanced and new shocks in but still does it..

Magna's are well known for thier CV joints, I own a 1991 TR model magna, cv joints have been replaced on a yearly basis. This may be the cuase for your shaking.

Check you tire presures are even, tires balanced and screwed on properly.

Then check out as above.