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Discussion Starter #1
I have a 2003 RC51 SP2 and am in the process of a performance build.
IMHO the GILLIES TOOLING TRIPLE TREES are the best on the market. They are truly adjustable as you can change both the rake AND the trail of the motorcycle with shims. This can be easily done without taking the triple trees off the bike . to save a bit of track time and a few $$ on shims , which direction would you go? more or less rake ? .... more or less trail?

You can purchase Gilles tooling triple trees at http://www.oppracing.com

Again IMHO they are the best , but they are not cheap look to spend around 1300$ for a set
 

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The rake is fixed as the steering head is welded to the frame.
What you're changing with adjustable triple trees (yokes) is the amount of trail.

Less trail quickens steering response at the expense of stability.
Just as increasing trail lessens the steering response in favor of stability.

The advantage of adjustable yokes is you can vary the amount of trail without changing the attitude or geometry of the bike.
Otherwise, the same effect can be had by raising the rear and/or raising the forks in the triple trees. But that alters the attitude of the bike.

Be very careful when decreasing trail as too much can make the bike very unstable.
Just a small amount can make a big difference, especially if combined with changing the ride height at the rear or front (or both).

Think of modern fighters.
They are designed to be incredibly unstable and naturally uncontrollable, with the pilot totally reliant on the avionics to keep the plane flying in a straight line.

The less expensive method is to use Attack Performance adjustable triple trees.
They use inserts of varying amounts to alter trail. May not be as easily adjustable as Gilles, but they are around half the price.
 

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Discussion Starter #3
Sub you are correct and not correct, yes the rake is fixed in the steering stem but can be increased or decreased by changing the angle in the stem itself. The trail can be changed increasing or decreasing the distance of the fork tubes to the stem of course but my question is which initial direction should i go for this particular motorcycle ? My riding skills have deteriated substancialy due to a broken/deteriating spine and my size being i am 6ft4 240- lbs 250 with only 8% body fat = im a big guy= not the size for motorcycle racing.

Is the rc51 considered slow at changing direction ect ect any help would be appriciated . Jake
 

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Sub you are correct and not correct, yes the rake is fixed in the steering stem but can be increased or decreased by changing the angle in the stem itself. The trail can be changed increasing or decreasing the distance of the fork tubes to the stem of course but my question is which initial direction should i go for this particular motorcycle ? My riding skills have deteriated substancialy due to a broken/deteriating spine and my size being i am 6ft4 240- lbs 250 with only 8% body fat = im a big guy= not the size for motorcycle racing.

Is the rc51 considered slow at changing direction ect ect any help would be appriciated . Jake
What you're changing is not rake, but fork angle.
The rake is fixed, but the adjustable triple tree allows fork angle adjustment.

If you measure the distance from a vertical line through the wheel center with a line through the center of the fork tubes where they intersect with the road surface, that is trail.

By altering the fork angle, you're altering the intersect point of the line down the fork tubes.
Disregarding rake (since it's fixed), if you steepen the fork angle (using the triple tree adjusters), you'll be bringing that intersect point closer to the wheel's vertical intersect point, thus decreasing trail.

If you want to make your bike's handling quicker, then use the adjusters to decrease the fork angle (make it steeper).
That will shorten the trail number.

Again, don't go crazy with the adjustments. You're making the bike handle quicker at the expense of stability.
 
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