F4i forks swap for Superhawk. Simple write up for ref.

[Karbon]

So i decided to go with an f4i swap, mainly because i wanted externally adjustable compression damping. Granted, ideally a set of Racetech valves would have been the cheaper solution, but primarily I just wanted to tinker a bit. I went for standard forks for budgetary reason.

For the most part the swap is pretty straight forward. You will need spacers.

Components list:

F4I PARTS USED:
upper & lower triples
Axle and axle bolt
clip-ons
Steering head bearings, same as Shawk's. I'm using tapered roller bearings.
Front fender
Horn
Steering head flange nuts and top nut. Same on shawk.
Ignition lock bezel

SHAWK PARTS USED:
Wheel spacers.
Front wheel
Brake calipers and lines (S.S. lines)
Ignition lock
Switch gear
Brake and clutch lever
Bar end weights

PARTS NEEDED FOR THE SWAP:

Wheel spacer.
A 6mm wide, 28 mm OD, 20 mm ID wheel spacer for use with OEM shawk wheel spacer.
This spacer will sit next to the large OEM spacer on the right side. Fully assembled, the f4i axle will install normally. Using the Shawk axle will cause the axle to be inset within the axle well. I used the shawk spacer because it was available at the time. Using OEM f4i wheel spacers will also require a custom spacer.

Caliper spacers.
4- 3.5 mm spacers to center the brake caliper. This should center the rotor well enough into the slots. If want, you can use a 4 mm spacer on the right caliper. This will get it the rotors to slot dead nuts center. Braking hasn't been an issue using the 3.5mm spacers.

Caliper bolts.
4- M8 1.25 x 35mm grade 12.9 or better flange bolts to accommodate the caliper spacer and thread.

FORK POSITIONING
31 mm above the triple works with my riding style. I initially started with the forks 28 mm above the top triple, which gave the same if not a close axle-to-bottom of steering head tube distance of 515 mm, IIRC. After setting sag and initial damping settings and test riding i found 28 mm a little on the heavy side. My guess, due to the increased trail. I suspect the f4i yokes have a shorter offset.


ISSUES
Clip-ons.
Using the f4i clip ons you will need to drill new index mounting holes for the throttle cable housing and on/of/start switch. The hi/lo and turn indicators slot properly into place using the existing index holes.

Switches.
The switch gear will touch the tank in the stock f4i position and will adversely affect lock to lock steering and pinch your hands and the normal return of the throttle tube. You can move the clip-on up and out of the indexing slots from the triple and rotate it or grind of the indexing tabs off completely. In any case, there is suitable length of fork tube to work with. You will have to lose the fork retaining rings.

Ignition lock.
The ignition lock unit will have to be shimmed abt 4mm or so in order for the steering locking mechanism to engage properly.

Throttle side bar end weight.
As setup on my bike the throttle tube extends a little bit over the bar. You can install a nut between the bar end weight and lug and tighten down the screw.

So far...
Overall, my initial impression is positive. The bike looks stock. The rigidity of the forks are noticeable and as a result the bikes vibration feels different. The damping is more versatile as now you can balance the damping rate between the rear and front ends more easily. Bear in mind I've logged about 67k miles and a trackday with the stock front end, running almost exclusively Pilot Power 2cts. So i feel i have a good basis of comparison.

More info as I progress.

250 mile update: I've ran the bike at a really fun pace on a few "control" roads of varying conditions with some finalized suspension settings. So far so good. Bike turns in virtually the same as with the OEM shawk forks, as i intended. The rigidity and whatever extra trail i gained with f4i forks makes the bike feel noticably stable in turns, although now the bike is more apt to stand up during mid corner braking.

Front suspension setup:
10 wt oil
.9 kg/mm fork springs
Rider sag: 34 mm
Rebound damping: 1 turn in from full-soft.
Compression damping: 1 turn in from full-soft
34 psi cold front and rear,

Jamie Daugherty f4i shock with a 950 in/lb spring.
Rider sag: 36 mm
sorry don't remember the rear damping settings.

As you can see, it looks like as if nothing has changed. "Hella flush, bro" as they say in tuner talk.

 

[Wicked4Racin]

nice post, my step dad has a hawk and he just did the rear 600rr shock conversion, now looking to do something with the front end. Is this the most common conversion or does anybody do a 600rr front swap?

 

[jimboFosho]

This is a good post. Very detailed and I'm glad things are turning out well from the swap

 

[Karbon]

nice post, my step dad has a hawk and he just did the rear 600rr shock conversion, now looking to do something with the front end. Is this the most common conversion or does anybody do a 600rr front swap?

I dont recall what the specific issue is on the early model 600rr, but i don't think it is a very common swap.

i can't say for sure what the most common swap is, i'd imagine there a good number of people that do the 929/954/rc51 swap, although this requires a bit more parts to source.

 

[Junkie]

I thought damping was generally done in turns out from full stiff, rather than in from full soft. No?

 

[Karbon]

I thought damping was generally done in turns out from full stiff, rather than in from full soft. No?

I go from factory settings and adjust from there. once the suspension was set it was easier for my sake to count from full out.

 

[Junkie]

My recollection is that total turns of adjustment can vary a little bit depending on details of how it was put back together, and turns out from full stiff is what matters.

 

[Karbon]

Ahh yess. Just read up on it. It makes sense why that is.

The factory settings i set were from full in, fortunately.

I'll have recount the turns to correct my notation and refer from full in just in case.

 

[stangmx13]

Karbon,

what the viscosity (cSt) of the fork oil u are using? if u dont have the cSt, which brand & model? im surprised u r running the damping settings so far out, but a heavier oil compared to mine could be the difference.

 

[kiltwearinfool]

there a good number of people that do the 929/954/rc51 swap, although this requires a bit more parts to source.

When I was thinking of swapping out the fork on my SHawk, I found that the predominant swap of choice was the 929/954 front end. Most that I had heard about simply swapped the fork, wheel and axle assembly, brake calipers and reservoir. Some that wanted to keep the SHawk front wheel for appearances learned that there was a bit of engineering to get it to work, from what I remember - more than just throwing in some spacers.

In the end, I dropped the fork in the triples a bit, switched from Dunlops to Pirellis, and told myself it was just as good A good choice, because I sold the bike abt a year and a half later.

 

[Karbon]

Karbon,

what the viscosity (cSt) of the fork oil u are using? if u dont have the cSt, which brand & model? im surprised u r running the damping settings so far out, but a heavier oil compared to mine could be the difference.

Runnin silkolene pro rsf 10wt. Which is what i had floating around, according to peterverdone.com, 45.68cst@43c. Which i guess explains why. Also, i've been riding a lot of super tight and bumpy stuff, the kinds where you're hovering over the seat and using lots of legs. Despite that it's only mere low speed damping i'm controlling, i've found the softer settings are a lot less fatigueing to ride with.

When I was thinking of swapping out the fork on my SHawk, I found that the predominant swap of choice was the 929/954 front end. Most that I had heard about simply swapped the fork, wheel and axle assembly, brake calipers and reservoir. Some that wanted to keep the SHawk front wheel for appearances learned that there was a bit of engineering to get it to work, from what I remember - more than just throwing in some spacers.

In the end, I dropped the fork in the triples a bit, switched from Dunlops to Pirellis, and told myself it was just as good A good choice, because I sold the bike abt a year and a half later.

Yea, initially concerned about using the shawk wheel mainly because in essence there is 6mm more f4i axle being subjected to shear forces. But so far its been good. Eventually i'll have to inspect that axle for runout just in case.

Yep, for what they are the OEM forks arent bad. Proper springs and fresh oil does wonders.

 

[stangmx13]

Runnin silkolene pro rsf 10wt. Which is what i had floating around, according to peterverdone.com, 45.68cst@43c. Which i guess explains why. Also, i've been riding a lot of super tight and bumpy stuff, the kinds where you're hovering over the seat and using lots of legs. Despite that it's only mere low speed damping i'm controlling, i've found the softer settings are a lot less fatigueing to ride with.

...

makes sense. im running Maxima 7wt @ 26cSt. OE Honda Pro 10wt is 35cSt. id prob run the low speed soft as well over tight bumpy stuff.

if u havent already, start adding some shims to that compression stack and see how u like it. the stock stack Honda put in their 4port stuff is way light.

funny how some still reference PVD for that viscosity chart.