Jockey Journal Forum banner
1 - 3 of 3 Posts

·
Registered
Joined
·
1,065 Posts
Was wondering,, since a girder is how it is and not inline like a springer or hyd forks,, Does this then make the trees ? raked ?
The same geometry rules apply to girders as any other front-end: The linkages create off-set. If the linkages are of equal length, you have off-set but no additional rake. If the upper linkage is shorter, you have the equivalent of raked trees, with an accompanying loss of trail. If they're the same length, you don't have a decrease in trail. Increasing the off-set, even equally, also decreases trail. This is why they make "in-line" springers: The decrease in off-set compensates for the springer rocker.

If -for example- you compare the trail of a springer which is in-line, with a 2.5 inch distance from the rocker pivot, to a glide front end with 2.5 inches of off-set in the trees, all other factors being equal, the trail will measure out the same.

But...girder front ends often have MORE off-set in the linkage, than standard springers have at the rocker. So you could have half an inch more off-set, and therefor it would then have less trail than a glide or standard springer. Also, SOME springers have the LOWER linkage made shorter, which gives an APPARENT de-rake, but increases the trail. This is done to compensate for non-parallel girder legs.

All that may seem complicated, but it's really not: It boils down to 3 possible measurements: Off-set, parallel linkage, or non-parallel, and whether the shape of the girder legs runs parallel to the steering neck centerline or not. That's it.

If you have un-equal length girder linkages, the SHORTER linkage is designed to go on the bottom, to increase the trail.

Hope you're able to digest that.
 
1 - 3 of 3 Posts
This is an older thread, you may not receive a response, and could be reviving an old thread. Please consider creating a new thread.
Top