Having this ****ling thought that it cant be that hard to compute how much a bike drops with a 3% rake. Something to do with math, a gentleman called Pythagoras and a triangle with one corner of 90%. Probably something every fifth grader can do but I don't recall anymore. Too long ago. Any bright fifth graders around?

 

Mine dropped the front 2", so I bought 2" longer fork tubes but havent installed them yet. also has a 1" drop in the back and it rides the same as before the worl.. And the lock on the neck will not work with this mod... I have some pictures posted on here, just look at my profile......

 

Ah, many thanks. I just looked at the pics at your profile. Yes, that makes sense, you can also compensate by fork tubes. Had not thought of that, so good tip. Now I'll wait for a reply from Vulcan, dont want to order the wrong part.

 

It's not just the drop from the rake it's also a drop from having the cup on top of the neck which effectively moves your tubes up. The cups I used for the streetbob would be exactly the same for fatbob.

 

See what you mean. Upper tree bracket rises. Slider tube must come up this distance. Lower tree bracket just slides down. You actually loose some distance between top of fender and bottom tree. Just out of curiosity why do the call it a triple tree when the are only 2 of them? Going to put this is my CAD system and let it trig and sketch it out. Anyone know this length for my calculations? Going to use 3/4"..sound about right. I am going to do my wheel base. What's some other wheel bases of a Sporty or Dyna?
Just round off my values on my rough drave. 3 degrees turns out to be a lot. Would drop mine apx. 2 5/16 or so.

 

I been considering a little more rake and using 3 degree cups. But so far the 2 vendors i talked to said I can't use cups if I have raked trees. Does anyone know the technical reason why they won't work?
Thanks

 

Still no response. Think they dont have the part or dont want to sell.

 

Mate I've heard before they don't have good correspondence but I know when I ordered I got the part shortly after.
I had 2 degree trees and 3 degree cups seemed to work ok.

 

Got a reply, they say part #4360 will fit. I'll order but need to sort out the engine and fuel tank before I get to raking.

 

So if you put in 2 inch longer fork tubes, you may have to drop the bike at the rear a little too. Or take even longer fork tubes and cut them down.

How does one actually measure whether a bike is level? I guess you do it under load, with the rider sitting on it. But how would you measure it exactly?