Trail Question

Forewarned said:

I wasn't shooting for a specific trail number, I just needed my bike to finish the corners better on the gas. And I was also rubbing my front tire on the radiator shroud under braking at turn 14 of Thunderhill resulting in the rear tire dancing and coming up too much. So I was solving multiple problems when I did all those mods.

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SuperDomestique said:

What trail figure did you ultimately arrive at? And was this for a V4?

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Forewarned said:

I didn't calculate it because I don't have a chassis program, and I don't know how to do it other than that way. I was going on feel rather than numbers because there's no real info out there to compare to. I'm happy with the results though, now I need to dial in the rear. The bike is a 959.

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Forewarned said:

That calculator says 103.6 Trail, 94.2 Normal Trail. But that doesn't calculate where my forks are in the triples which changes trail.

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SuperDomestique said:

Not necessarily. Depends on who you talk to. Adjusting fork length will affect rake relative to stock position. I’d assume stock position I had 8-10 mm fork (5 mm anodized) exposed. Move the forks to flush with triple increases fork length and therefore rake which then increases trail.

I’m also assuming that all these figures are determined with no sag factored in.

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Forewarned said:

Honestly because I have aftermarket triples that are thicker that stock, I have no idea where the forks are compared to stock. For all I know flush on the top triple could be the same as 5mm showing with the stock triples.

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andyb said:

yep me too....exact same conclusion and changes!

But as us amateurs some cynics would question can we really feel these millimetre differences...

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baggerman said:

What I think is your change may be too subtle for them. I know you must have run the bike at some point with the front dropped to give you the 24 degree head and the associated trail. But instead you made bushings, which pretty much leave the CG and ant-squat alone. I'm thinking that wasn't by accident. I actually think your set-up would be good for SD as he's light so his bikes CG is lower to begin with and goes lower dropping the front. Ducati moved the CG up at the 22 (?) revision for a reason.

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