Want to build triple tree for Busa Forks

[TURBOVMAX]

Option... more here Custom Vmax Services

 

[[email protected]]

Looking to get the overall length of the tube to axle C/L

Fork length fom c/l of axle to top of fork cap is 708mm.
The upper triple is 70mm thick. You could slide the forks down if needed and gain 50mm of length.
With the fork tube spacers in place length from c/l of axle to top of triple is 816mm

 

[TURBOVMAX]

Thank you Mike. Looks like Aaron has some good info to get started.

 

[AMechEng]

 

[AMechEng]

Sorry for the delay. I've been slammed with school. This is where I'm at with the design. I need to get dimensions for the stem so I can dimension the stem holes. I also need to pick out what kind of bolts to use to tighten the triple trees on the forks. I'm thinking stainless allen bolts but not sure what size. Is the Vmax stem usually reused with custom trees? If anyone wants any files related to this PM me your email address.

 

[naughtyG]

If you're going top make these for a Gen I, remember that you need to offset the fork holding bits down quite a bit because most inverted sports bikes forks are way shorter than the Max's OEM items.

 

[TURBOVMAX]

Sorry for the delay. I've been slammed with school. This is where I'm at with the design. I need to get dimensions for the stem so I can dimension the stem holes. I also need to pick out what kind of bolts to use to tighten the triple trees on the forks. I'm thinking stainless allen bolts but not sure what size. Is the Vmax stem usually reused with custom trees? If anyone wants any files related to this PM me your email address.

Lookin like a good start Aaron! I can get you the dimensions for the stem this weekend. You would be better off making your own. I made the one for the dragbike out of 7075T6 and used a locking collar nut rather than the... two nut lock that Yamaha uses. Just set the pre load on the bearings and tighten the allen cap screw.

Here's a link if you decide to go that way... Threaded Clamp-On Shaft Collars

Another cool thing about McMaster Carr is that you can download cad files for many of their products and import directly into Solidworks or??. Check this out Cad Files

 

[AMechEng]

If you're going top make these for a Gen I, remember that you need to offset the fork holding bits down quite a bit because most inverted sports bikes forks are way shorter than the Max's OEM items.

I'm not sure how I'm going to handle this yet. I figure I have three options:
1. Use extensions for the top of the shocks that lock into the top tree to push the shocks down (cheapest option)
2. Extend the two tubes which lock the shocks several cm downward so that the shocks can be raised or lowered as needed. If I make the top tree as one billet piece, this will cost much more for material.
3. I can design the upper tree (and maybe the lower tree) as three separate pieces that bolt up to be one piece. This will save money for materials but it may be a wash with additional machine cost.

Right now my bike is lowered 2 inches in the front in back. I guess I need to figure out what the difference will be when using a larger 17" wheel with the shorter Busa forks so that the bike stays lowered where it is at. I guess if I can raise and lower the Busa shocks in the trees the added flexibility will be nice.

 

[one2dmax]

I believe the OEM triples have some amount of rake in them. Are you going to replicate that too so the rake/trail is maintained?

Sean

 

[AMechEng]

TURBOVMAX- Thanks for the advice. I was thinking of using steel for the stem but 7075T6 will work and will save on weight. The locking collar seems like it will be a better option as well. If you can get the dimensions for the stem that will put me much closer to the finish.

one2dmax- Truthfully, I haven't considered the rake and trail yet. I would like to keep it close to stock unless there is a reason to change it. The forks and steering head appear to be perfectly parallel leading me to believe that the only rake in the front is from the 29 degrees that the steering head is off vertical.

 

[one2dmax]

I'm pretty sure there is some amount of rake in the triples but can't remember what it was.

Sean