TC96 Front Forks

[Rob the Dog]

Hi All, can anyone help.. I have a 2009 Dyna Street Bob cross From First Registration with many Fat Bob parts such as Front End by way of a Fat Bob Off Side Slider Yokes Front Wheel….. thinking I didn't need to swap out the Fork Tubes or internals as I assumed they were the same……
It did bother me that something still didn't look quite right, but I parked it there and have now done 53,000 odd miles and am thinking the Fork Seals are a bit tired and the fork tubes have already been turned round so that the newer rear surface no face front.
I looked at part numbers because Street Bob forks seem to sag compared to Fab Bob ones…. By that I mean the measured distance from under the bottom yoke to the top of the chrome Slider Cover please see mine (first two photos ) and the library photos attached. Front Fork Part Number give GY code for Fat Bob exclusive part numbers for Chrome Fork Tube/Fork Pipe 48745-08
And Bottom Pipe 48742-08.
Anyone know why this and what the differences are ? ( I do think though, all fork tubes are 25.5inches even the Fat Bob )
So, can it be the Bottom Pipe that is a different spec or longer to allow the fork slider to give a further distance at rest from the bottom of the Top Yoke ?
What do you think ?

 

[watchman]

Hi mate its the internals the spring ,damper tube and spacer length on a fatbob are different to the streetbob as the fatbobs part numbers show, its springs and damping rates are different due to the twin disc and cast wheel unstrung weight and some rake differences to make a fat bob handle well and at 50k miles the springs are starting to sag with age and wear when you overhaul the legs sling a set of progressives in and normal service will be resumed

 

[Rob the Dog]

Thank you….. I do have Progressives in, my second set and I used the Fat Bob spacer length as suggested by the instructions, but I think maybe I still need longer plastic spacers under the Top Nuts
Q. Do you think The Fat Bob Chrome Tubes or stanchions are of a different design in some way to warrant the unique part number, as I think all of this Dyna range Share the same fork tube length of 25.5 inches ? If the length is the same, the fitting for the bottom pipe must be different in some way
I suppose I could buy the Fat Bob bottom pipe/damper tube and see why it wont work with Street Bob Chrome Fork Tubes before I splash out on Fat Bob Tubes ?
Many Thanks

 

[watchman]

I just checked all the bushes ect part numbers and so on and they are all the same all i can think is that there may be a difference in the tube length or the tube wall thickness because of flex due to twin disc and unstrung weight i found one yank site that gives fatbob tubes as 26” but i am not 100% sure without putting a set side by side

 

[Rob the Dog]

Thats grand thankyou…..yes, as you say differences that might not be visually immediately obvious, I’m gonna bit the bullet and buy all the GY part numbers