Title: Fork swap Post by: SDkid on June 05, 2012, 01:19:38 PM After searching and researching, here are the questions I have come up with:
I have a 2002 M750ie Dark, and I found a local set of 999 forks I am considering swapping out. I know the top triple would have to be machined, my questions lie in what other mods have to happen to get these to bolt up. Is there an adapter for the stock Brembo 60mm (or 65, I can't remember what I measured) calipers to mount onto the new fork 40mm mounts? I saw the rotors may need to be offset (or the calipers pushed inward with spacers, a controversial move since I don't want to buy an SBK rim for the front). Also, does anyone know the size of the axle I need? Is it a direct changeover for that piece at least? I know I would need to drill a hole to get to the bottom adjustment screw, but I want to make sure I am not getting in over my head and changing out every single piece if I wasn't planning on it. With this, I'd plan on clip ons, so don't worry about educating me about that requirement; I know the stock bars won't fit there anymore. I think my biggest question is about the brakes and axle, since I couldn't find any definitive answers about that. Title: Re: Fork swap Post by: corey on June 05, 2012, 03:23:45 PM 999 forks should have 65mm caliper mounts. The 749/999 bikes weren't around until well after the switch from 40mm mounting centers.
You do need to shim your lower triple, and bore your top (or buy aftermarket, either works fine). Since you are keeping your stock wheel, use your stock axle. You can have it drilled with the holes needed for rebound adjustment if you so desire. A 999 axle will not work, ask me how I know. The measurements for your brakes — since your are using your stock calipers, wheel, and rotors — have absolutely nothing to do with rotor offset, but rather FORK offset. Your calipers just need to be in the same position they were in previously. Unfortunately the 999 forks have 5mm more offset at the caliper mounts than your stock forks. Thus, you need to space your calipers 5mm toward the rotor. Not really that controversial, a few folks have done it, including myself. With the 5mm spacers, you will also need slightly longer caliper bolts. At this moment, there just so happens to be a fellow selling bolt and spacer kits in our classifieds: http://www.ducatimonsterforum.org/index.php?topic=57613.0 (http://www.ducatimonsterforum.org/index.php?topic=57613.0) Nice for you, as you don't need to worry about machining spacers now! A couple things to keep in mind: 999 forks will be significantly stiffer than your stock forks. How much do you weigh? 999 forks should be a .95kg spring rate (I think). 999 forks also have different stepping/tapering in the fork legs themselves than the monster does. The tapering near the bottom triple, which is likely exactly where you'll have to mount them, will change your bike's geometry slightly. Your trail measurement will be shorter, and thus turn-in will be quicker. Also, a very important note, your stock handlebar will need to be replaced with clipons, as the fork sticking out of the top triple will interfere with the stock handlebar setup. If the forks are a good deal, and don't have a ton of miles on them, I'd say go for it. Title: Re: Fork swap Post by: SDkid on June 05, 2012, 03:38:49 PM I asked for some pictures and he sent me the ones on the link here.
http://denver.craigslist.org/mcy/3032844554.html (http://denver.craigslist.org/mcy/3032844554.html) this is the older ad, they've been up for a while. http://denver.craigslist.org/mcy/3007570500.html (http://denver.craigslist.org/mcy/3007570500.html) From just the look of it, the caliper holes are closer together, and it was confirmed when he measured it with the caliper in the picture. Are these pretty old 999 forks, or are they something different and he's not sure what they are? Title: Re: Fork swap Post by: Nottsbiker on June 06, 2012, 04:48:29 AM Look like early 916 forks to me with 40mm calliper spacing.
I've got a set of these waiting to go on my 900. Title: Re: Fork swap Post by: corey on June 06, 2012, 06:36:49 AM yea, definitely not 999 forks. MUCH earlier than that... Check out that Cagiva elephant logo on the one fork leg! Love it.
They DO make brackets to put 65mm calipers 40mm caliper mounts, but for the money ($200), I'd say wait it out and find a pair of newer forks with the proper mounts, and less age. 748 forks would be good, really any recent SBK aside from 749/999 would be a direct bolt on aside from triple clamp modifications. My advice above would still stand if you find 999 forks. Title: Re: Fork swap Post by: SDkid on June 06, 2012, 06:53:53 AM Thanks Corey.
On ebay (for reference) it looks like some of the 748 caliper mounts are similar to the narrower 40mm bolt pattern, while others are 65mm (all estimation from the pictures). Is there some variation with that style? I did find a couple decent 999 sets, although I like the idea of the more direct bolt-on use of the 748 style. Looks like the fender I have will bolt right up, compared to the 999 forks. Is pitting or scuffing to the outer surface of the forks a big deal with these? I plan to wrap them in vinyl like I currently have, I just want to make sure it's not like a crack in the hull of a ship and will eventually break. Title: Re: Fork swap Post by: corey on June 06, 2012, 11:28:27 AM Thanks Corey. On ebay (for reference) it looks like some of the 748 caliper mounts are similar to the narrower 40mm bolt pattern, while others are 65mm (all estimation from the pictures). Is there some variation with that style? I did find a couple decent 999 sets, although I like the idea of the more direct bolt-on use of the 748 style. Looks like the fender I have will bolt right up, compared to the 999 forks. Is pitting or scuffing to the outer surface of the forks a big deal with these? I plan to wrap them in vinyl like I currently have, I just want to make sure it's not like a crack in the hull of a ship and will eventually break. If it's the fork leg itself, scuffs or slight mars shouldn't be an issue, just be sure they weren't wrecked and bent up. I'd avoid "pitting," as that could be a sign of corrosion of the aluminum if it's severe. Make sure the fork SLIDERS (lower part that travels) are in perfect condition. Scratches, pits, or other damage to these sliders will cause the forks to leak. Maybe some other folks can chime in as to which SBK forks have 65mm mounts and which do not. Aside from SBK forks, you could also look at some ST forks, or even some S2R1000 forks, which would require no modification to install at all (no triple clamp mods). Title: Re: Fork swap Post by: Grrrly on June 06, 2012, 08:52:03 PM Maybe some other folks can chime in as to which SBK forks have 65mm mounts and which do not. The first few years (I believe 94-98) of the 748/916 had the 40mm brake mounts. They also had craptacular electrics. Once they got to 1999 (and the 996's) they became the 65mm brake mount. IMO, these early SBK legs were only better for the pre 2000 monster folks that wanted to do the SBK swap cause they already had the 40mm calipers to use. Corey is offering you excellent advice ~2001chromo (logged in under my girlfriend's acct.) Title: Re: Fork swap Post by: Nottsbiker on June 07, 2012, 04:29:15 AM The first few years (I believe 94-98) of the 748/916 had the 40mm brake mounts. They also had craptacular electrics. Once they got to 1999 (and the 996's) they became the 65mm brake mount. IMO, these early SBK legs were only better for the pre 2000 monster folks that wanted to do the SBK swap cause they already had the 40mm calipers to use. Corey is offering you excellent advice ~2001chromo (logged in under my girlfriend's acct.) Which is exactly why I went with them over the later 65mm versions ;) Title: Re: Fork swap Post by: SDkid on June 07, 2012, 08:54:40 AM in consideration of brake rotor size, will I need to change out to something larger (320mm) if I go with the 748? Corey mentioned a much more bolt-on experience except for the top triple and handlebars, are the stock rotors good to go with these forks?
Title: Re: Fork swap Post by: corey on June 07, 2012, 09:36:40 AM If you use your stock calipers, stock wheel, stock axle and stock rotors, everything should bolt right on. even your fender. You'll need to bore your top triple and shim your lower triple. there may be the possibility of needing to switch to clip-on style bars due to fork length sticking out above the top triple, but I do not know for certain.
90% of modern ducati rotors are 320mm. S2R800's, M695's and i think SC1000's have 300mm rotors. Some of the late SBK's (1198?) have 330mm rotors, but you won't be using those. Title: Re: Fork swap Post by: SDkid on June 07, 2012, 09:40:24 AM Great information. Thanks for helping me out with all this. Definitely saved me some headache and frustration.
Title: Re: Fork swap Post by: corey on June 07, 2012, 12:43:32 PM Great information. Thanks for helping me out with all this. Definitely saved me some headache and frustration. No problem at all, feel free to post up any more questions you may have. Also — again as a reminder — do keep in mind that SBK forks will be stiffer, and if you're a light guy may need to be resprung. I'm not positive of the life expectancy of forks, but the 16,000 to 18,000 mile range seems to be where people like to get them rebuilt, something to keep in mind. Title: Re: Fork swap Post by: SDkid on June 07, 2012, 01:09:14 PM I don't think I mentioned it before, but I was thinking of rebuilding my old forks, but this would be better. I am about 190, and well over 200 with gear and my backpack for school. Either way, rebuilding SBK forks seems a better investment than rebuilding the stock ones. Now I'll just need to address the rear. Is a spring only replacement usually enough to improve normal daily riding? I'm not sure I want to spend 500 on a shock at this point.
Title: Re: Fork swap Post by: moto on June 07, 2012, 02:09:36 PM You do need to shim your lower triple, and bore your top (or buy aftermarket, either works fine). MOTOWHEELS Lower Triple Clamp Conversion Shims (http://motowheels.com/i-8121511-motowheels-lower-triple-clamp-conversion-shims.html) Title: Re: Fork swap Post by: corey on June 11, 2012, 05:00:50 AM I don't think I mentioned it before, but I was thinking of rebuilding my old forks, but this would be better. I am about 190, and well over 200 with gear and my backpack for school. Either way, rebuilding SBK forks seems a better investment than rebuilding the stock ones. Now I'll just need to address the rear. Is a spring only replacement usually enough to improve normal daily riding? I'm not sure I want to spend 500 on a shock at this point. What type of riding do you do? Assuming you are like the rest of us, it's probably mostly weekend warrior stuff, with some spirited jaunts through some twisties now and again. If your current forks are in need of rebuilding, consider that SBK forks would likely need rebuilt sooner rather than later if you get a set that is used. It's a tough call, but a proper rebuild by folks who really know what they are doing could be just as good as an SBK swap. Proper springs, proper oil, and some upgraded valving — while not adjustable — will make the bike feel completely different. To be quite honest, I've not once adjusted my 999 forks since putting them in. I checked the sag, it ended up being spot on, so I left them alone. The benefit of the swap for me was that I had ONE day of downtime, and was back on the road... Rather than pulling the forks, sending them off, etc. etc. Maybe talk to some folks at Traxxion Dynamics or RaceTech, or see if you have any local shops. I'm not sure what's out there regarding valving, etc. for your bike. |