SBK Fork Swap - WWDMFD?

[Staggerlee]

So I'm slowly amassing the parts needed for a SBK fork conversion on my '00 M900S; right now I'm at the buy-the-forks stage.

Poking around on the internet, it seems that I can pick up a set of forks from a 748/916,etc for somewhere in the neighborhood of $250-275 delivered.  Figure another $150 or so in seals & correct rate springs (I'll be doing the rebuild) and I'd be right around $425 plus whatever blood, sweat & tears are shed during the rebuild.

I found a set from a 748 that were just completely rebuilt with seals, valves & springs for $375 to my door.  They were supposedly set up with either .90 or .95kg/mm springs; the guy doesn't recall for sure which.  Factory for the 748 would have been 1.020kg/mm

I weigh in at 165lbs, sans gear.  Running the #'s on Race Tech's site, it looks like my ideal setup would be .85kg/mm springs.  Knowing that, would it be worth tossing the dice and seeing how the $375 forks would perform, or would they be at best, simply too harsh for street use and thus require another $100+ to set up correctly?

[stopintime]

Assuming .85 is correct, adjusting preload by 5-10% should do it for you.

(I'm not your expert here - just trying to be logical)

[Buckethead]

ducvet, paging ducvet to the SBK Fork Swap thread...

ducvet to the Fork Swap thread...

[Staggerlee]

Assuming .85 is correct, adjusting preload by 5-10% should do it for you.

(I'm not your expert here - just trying to be logical)

Logic?  What is this concept of which you speak?

The .85 comes direct from Race Tech's calculator; I can only assume it's accurate. The only other variable is the actual weight of my bike; I'm guessing with the carbon cans & Rizoma rearsets it's few pounds lighter than their default numbers.

I appreciate the feedback; perhaps it's worth taking a shot with these.

[mtn_mnztr]

I had the fork swap done years ago, so the spring rate details are foggy, but I do remember that with stock sbk forks/springs the ride was pretty harsh.

I chalk it up to the differences between the two bikes.  The 748-998 sbk is heavier, more weight is distributed forward, and the riding position puts even more weight forward versus the upright and blowing in the breeze position on the monster.

So after being bounced around for awhile I put in new springs and Ohlins cartridges, and the transistion was amazing.

Good luck with the mod.

[Speeddog]

At 165#, yes, the .85 springs would be what I recommend.
.90 or .95 will be quite stiff.

Swapping the springs on the $375 748 forks will be a lot less work than doing the whole magilla on the ~$250 forks.
Depends how much $ you charge for your own time....

[junior varsity]

i had the racetech valves/springs done on my oem '99 monster showa forks.

not enough of a difference for the money (springs were fine, valves were blah)

i've got a set of 748 forks with ohlins internals to put on now. hopefully much better.

if you have some extra jingle, seriously eyeball the 848 (or better yet, the 1098/1198 for the black ti/ni coating) forks. You will go to radial brakes (need new rotors...different offset), but it will have modern brakes and fork technology.

then again, any brembo 4-pot calipers are good

[Staggerlee]

Cool, thanks guys; it looks like I'll be coming into a few extra bucks this month so I'm gonna go ahead and pick 'em up.

Swapping the springs on the $375 748 forks will be a lot less work than doing the whole magilla on the ~$250 forks.
Depends how much $ you charge for your own time....

That's kind of what I'm thinking.  I pretty much work for beer, so labor costs just end up being a wash.

if you have some extra jingle, seriously eyeball the 848 (or better yet, the 1098/1198 for the black ti/ni coating) forks. You will go to radial brakes (need new rotors...different offset), but it will have modern brakes and fork technology.

Would be nice indeed; I've got a radial front end from a gixxer on my cafe'd CB550 and I'm flabbergasted at how much better it'll haul down to a stop than my Monster.  Unfortunately, I'm not gonna be coming into enough money to throw a grand or better at this little project.

[junior varsity]

pads be where its at then

[atomic410]

don't you need a top clamp as well for the 53mm forks and shims in th lower one?  better add that on you budget as well

[junior varsity]

you can bore the top triple to 53 from 50 and shim the lower, or buy a new top triple that's set at 53 already, and shim the lower, or buy a triple set where both are set to 53 from the get go.

One could look at SpeedyMoto or IMA. IMA is to your door for about half the price of SpeedyMoto, for those that are budget-minded.

[Staggerlee]

don't you need a top clamp as well for the 53mm forks and shims in th lower one?  better add that on you budget as well

Already have that part taken care of; found a leftover Cyclecat triple on ebay.