Wobbly head!

Advice needed please.. the steering on my maxim 700 based trike wobbles under acceleration. The forks appear to be of an earlier 650 (single brake disc) so I'm not sure which bearings are fitted or whether they are even compatable! Being fairly new to bikes (last rode 16 years ago), how do I go about adjusting the headstock, and how do I know when I've got it right? What do I loosen/tighten or generally adjust and what should I be looking for to indicate a problem?

Cheers

Sam

 

Until you find out what's going on, and have rectified it, your bike needs to be parked.

http://www.motorcyclecruiser.com/tech/service_steering_head_bearings/

 

You can always check the balance of the front wheel too. That may make the front shake too. Also check the air pressure in the front tire.

 

Thanks for the advice... can anyone suggest what tthe front tyre should be? With this being a trike, rather than a bike, there's a lot more steering input and I'm still experimenting with tyre pressure on the front and the two rears.

Sam

 

Ah, ya - There is more that comes into play than just the air presure. It all depends on the weight on the frontend, compared to stock. The rake and trail may be changed during the fabrication. Is the steering head true? What kind of tire are you running? I guess your on your own with this one. Just be careful until you get it ridable! Good luck!

 

Best way to be sure of the steering adjustment is by checking fall off. To do this the cables must be detached from the handle bars so they don't interfer with the bearings free movement. Place a piece of masking tape across the front fender at the tip. Make a mark in the center with a pencil or pen. Elevate the front end so it is swinging free, i.e. front wheel is off the ground. You will need a pointer to read the fall off. This must be unattached from the bike. It only needs to be a reference for making marks on the masking tape. I use a small piece of copper tubing suspended over the masking tape with a nail in the end for a pointer. The other end is held in a board drilled to fit the tubing. The board is placed over two sawhorses which are clear of the bike and the front wheel's movement.
With the front wheel centered bend the tubing until the pointer is pointing directly at the middle mark on the masking tape. Gently push the handle bars in one direction until the wheel just falls on it's own. Make a mark where this fall off begins on the masking tape. Then do the same pushing the handle bars in the other direction. If the fall off on each side is an equal distance from the middle mark then all is well. If not then loosen or tighten the load on the steering bearings until it is. Distance between marks should not exceed 2 inches.
I will let someone else elaborate on the loosening and tightening since the 650 may be different from my 750.