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I'm thinking in replacing the forward shock absorbers of my Street Rod for the forward shock absorbers of the new H-D XR 1200 X.

Has anyone done this before?
 

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Hmmmm, WHY ?
You have perfectly fine Showa front forks on the R now.
They are not easy to rebuild yourself, I know. I am in the middle of that right now and I have had to fabricate 2 different tools to tear them apart. Neither fork is the same inside. Cannot figure this out as to why they made them different but the Showa's we have on the R models are good forks.
 

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I have. But it is not easy! First let me say that the stock forks really ain't that great. The ride is harsh and not anywhere near state of the art. You can vastly improve them by changing springs and valving. I had Race tech do mine and they came back so much better. But I can't leave anything alone for long, so I am now sporting a set of Showa Big Piston forks from the XR 1200 X. First, let me tell you they don't fit the "R"s triple clamps as they are machined and tapered differently. Oh, and there about 3 inches longer than the stock "R" forks. BTW the front axle, fender, and brake bolt up fine. I didn't want to change the "R"s clamps, so I had the forks sleeved to fit. I also sent them to Tony at Race tech to have them re sprung, and the latest valving up grades done. If you want to swap out the X triple clamps, it might make a much easyer swap. Ed...
 

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What is it that was improved about the 1200 X fork legs that Race Tech cannot do to the S. R. forks. How much of a hassle to have the forks sleeved to use the "R"'s clamps. Also how expensive is it to have Tony at R.T. do an upgrade. Thanks
 

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What is it that was improved about the 1200 X fork legs that Race Tech cannot do to the S. R. forks. How much of a hassle to have the forks sleeved to use the "R"'s clamps. Also how expensive is it to have Tony at R.T. do an upgrade. Thanks
The X fork is built using a totally different dampening system that showa calls "big piston technology". The X forks are adjustable for compression and rebound as well as preload. The R fork is not. These X forks are the current state of the art. I have read magazine articles that say they compare favorably to $20,000. Olin's factory racing forks. I don't Know about that. To have the X forks sleeved, was an expensive pain in the ass. If I had to do it again I would try to use the X clamps. But IMHO the R clamps are one of the most recognizable things about the R, and I wanted to preserve that. I can't remember the price for the work at Race Tech, allot of members here on the forum have had Tony do there R forks, perhaps one of them will remember the cost and chime in. I think it is around $350. with springs. Ed...
 

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Thanks, that's good info. I like the R clamps too.
 

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Hi DSB581. I'm considering exactly the same modification to my R in the near future. I have been taking measurements of the forks on the original XR-1200 and those would fit our bikes. They are about 50 mm ( 2 inches ) longer overall than VRSCR forks, but that is ok since we want to have the fork legs protrude a bit above the upper triple clamp so we can use the damping adjustments. I have measured the distance from the center of the axle to the upper brake mounting bolt and this is the same dimension as on the R, as is the distance between caliper bolts, so our Brembo calipers ought to mount to that fork leg, and they ought to be positioned the correct distance from the axle to allow the use of our stock 300 mm rotors ( XR's have 292 mm rotors, but the Nissan calipers mount on a bit of a dogleg compared to the Brembo caliper ).
Knowing this and knowing the X's Big Piston Fork can be swapped into earlier non-X XR's I believe the XR-1200X fork will swap to our bikes. But, I also know the X's fork mounts the caliper at a slight angle relative to the centerline of the fork leg compared to the vertical mounting of the original XR fork, and our fork. I do not know how this might affect the use of our Brembo caliper and larger diameter rotor. Brake Tech sells a 320 mm rotor kit for the XR and they had to use differrent caliper adapter brackets for each fork because of this slight angularity. I'v talked to their techs about this. This might not be a factor for our rotors. I also notice the X's fork has different diameters over the length of the upper stanchion. I'm certain it is 56 mm where it fits into the upper and lower triple clamps, just as with the R, but it necks down to a smaller diameter in between the clamps and below too. I need to measure the distance between the upper and lower clamps of an XR and see if this distance compatible with our triple clamps before I pop for those fork legs. I'd hate to slide that fork leg into my triple clamp and discover the larger diameter portions of the upper stanchion didn't line up with the triple clamps of my bike the way they do on the XR. This is a bit of an engineering exercise still in progress. I will be somewhere this weekend where I can take some more measurements of XR's so I'll keep everyone posted.
Btw, for the doubters, the X has the very best fork technology available, what is called a Showa Big Piston Fork. Our fork is pretty much the same thing found on the Valkyrie. It is a decent fork but not even close to the X's in terms of damping quality, and the X's fork is fully adjustable while our stock fork is not.
 

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Hi DSB581. I'm considering exactly the same modification to my R in the near future. I have been taking measurements of the forks on the original XR-1200 and those would fit our bikes. They are about 50 mm ( 2 inches ) longer overall than VRSCR forks, but that is ok since we want to have the fork legs protrude a bit above the upper triple clamp so we can use the damping adjustments. I have measured the distance from the center of the axle to the upper brake mounting bolt and this is the same dimension as on the R, as is the distance between caliper bolts, so our Brembo calipers ought to mount to that fork leg, and they ought to be positioned the correct distance from the axle to allow the use of our stock 300 mm rotors ( XR's have 292 mm rotors, but the Nissan calipers mount on a bit of a dogleg compared to the Brembo caliper ).
Knowing this and knowing the X's Big Piston Fork can be swapped into earlier non-X XR's I believe the XR-1200X fork will swap to our bikes. But, I also know the X's fork mounts the caliper at a slight angle relative to the centerline of the fork leg compared to the vertical mounting of the original XR fork, and our fork. I do not know how this might affect the use of our Brembo caliper and larger diameter rotor. Brake Tech sells a 320 mm rotor kit for the XR and they had to use differrent caliper adapter brackets for each fork because of this slight angularity. I'v talked to their techs about this. This might not be a factor for our rotors. I also notice the X's fork has different diameters over the length of the upper stanchion. I'm certain it is 56 mm where it fits into the upper and lower triple clamps, just as with the R, but it necks down to a smaller diameter in between the clamps and below too. I need to measure the distance between the upper and lower clamps of an XR and see if this distance compatible with our triple clamps before I pop for those fork legs. I'd hate to slide that fork leg into my triple clamp and discover the larger diameter portions of the upper stanchion didn't line up with the triple clamps of my bike the way they do on the XR. This is a bit of an engineering exercise still in progress. I will be somewhere this weekend where I can take some more measurements of XR's so I'll keep everyone posted.
Btw, for the doubters, the X has the very best fork technology available, what is called a Showa Big Piston Fork. Our fork is pretty much the same thing found on the Valkyrie. It is a decent fork but not even close to the X's in terms of damping quality, and the X's fork is fully adjustable while our stock fork is not.
Philthy, I may be able to save you a bit of time because I have done all those measurements. Here is the rub, The diameter of the upper and lower clamping surface on the X Fork stanchion tubes are not the same (as they are on the R). One of them is the same as the R, but the other is smaller ! (sorry, I can't remember witch is witch as it's been a few months since we worked on them). The other problem, as you correctly surmised, is that the distance between R clamps is wider than that of the X fork's mounting surface's. So when you fit the fork properly in to the clamps, the lower clamp is seated on the taper below the intended mounting surface. Way ungood ! So as I saw it, my choices were (1) to use the X clamps. I think that they are ugly compared to the R clamps and I did not want to have to deal with any possible angle of steering head rake, handle bar and headlight mount changes. (2) try to shim the lower clamp. Me thinks it unworkable, sloppy. (3) to sleeve the stanchion tubes. And that is what I choose to do. Ed...
 

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Philthy, I may be able to save you a bit of time because I have done all those measurements. Here is the rub, The diameter of the upper and lower clamping surface on the X Fork stanchion tubes are not the same (as they are on the R). One of them is the same as the R, but the other is smaller ! (sorry, I can't remember witch is witch as it's been a few months since we worked on them). The other problem, as you correctly surmised, is that the distance between R clamps is wider than that of the X fork's mounting surface's. So when you fit the fork properly in to the clamps, the lower clamp is seated on the taper below the intended mounting surface. Way ungood ! So as I saw it, my choices were (1) to use the X clamps. I think that they are ugly compared to the R clamps and I did not want to have to deal with any possible angle of steering head rake, handle bar and headlight mount changes. (2) try to shim the lower clamp. Me thinks it unworkable, sloppy. (3) to sleeve the stanchion tubes. And that is what I choose to do. Ed...
Well, well, well, thank you very much! This is the reason we have this forum. The top diameter would have to be the smaller of the two. If the top opening were the larger of the two, you would not be able to slide the top of the fork tube upward through the smaller opening of the lower clamp (the brake and fender mounting lugs on the lower leg would prevent someone from sliding the fork down through the triple clamps from the top). It also makes sense to have the larger opening on the lower clamp as this is where the greater clamping force is necessary.
Really good information, and thanks again. Now I reckon I'll activate Plan B; take the bike to Race Tech and be done with it.
Did sleeving the stanchion tubes work? Any pics of the result? It's hard to let the idea go, ya know.
 

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Wow, getting the correct taper for the inside of the sleeve would be a pain.

As long as you are going with new springs and valves; have you looked at other make forks or total front ends?
 

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Well, well, well, thank you very much! This is the reason we have this forum. The top diameter would have to be the smaller of the two. If the top opening were the larger of the two, you would not be able to slide the top of the fork tube upward through the smaller opening of the lower clamp (the brake and fender mounting lugs on the lower leg would prevent someone from sliding the fork down through the triple clamps from the top). It also makes sense to have the larger opening on the lower clamp as this is where the greater clamping force is necessary.
Really good information, and thanks again. Now I reckon I'll activate Plan B; take the bike to Race Tech and be done with it.
Did sleeving the stanchion tubes work? Any pics of the result? It's hard to let the idea go, ya know.
Yes, Philthy I have that same disease! The sleeve worked out vary well. It's was just a bit of a pain, I had to strip down the new forks, then chuck them up in a vary true lathe and cut down the diameter 110 thousandths and then machine a sleeve with an ID interference fit of 3 thousandths. We heated up the sleeve to 250 F and cooled the fork tube to 20 F and pressed them together. We then remounted the tubes in the lathe and turned down the OD to the original R dimensions. Next we sent them to be anodized and then back to Tony at Race tech to be reassembled with new springs and the latest valving mods. I will post up some pic's on Monday (going out of town for a few days) Ed...
 

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Wow, getting the correct taper for the inside of the sleeve would be a pain.
Yes, I think it would be
As long as you are going with new springs and valves; have you looked at other make forks or total front ends?
Yes, but I really wanted the big piston technology and to redo the brakes, fender mounts and axles can be allot of additional work also. Ed...
 

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Yes, Philthy I have that same disease! The sleeve worked out vary well. It's was just a bit of a pain, I had to strip down the new forks, then chuck them up in a vary true lathe and cut down the diameter 110 thousandths and then machine a sleeve with an ID interference fit of 3 thousandths. We heated up the sleeve to 250 F and cooled the fork tube to 20 F and pressed them together. We then remounted the tubes in the lathe and turned down the OD to the original R dimensions. Next we sent them to be anodized and then back to Tony at Race tech to be reassembled with new springs and the latest valving mods. I will post up some pic's on Monday (going out of town for a few days) Ed...
Oh-oh ! Ok, I know I should not ask this question but who did the machine work for you? I may do this yet. Oh, big question, did the Brembo's line up properly on the stock rotors? And did the fender mounting points work with the stock R fender bracket?
I had my trusty caliper out today at a dealership (Santa Barbara HD, see my other post in V-Rod General) and there was an XR for me to measure. What I saw was the outer diameter of the stanchion tube was 55 mm while that of the Street Rod, at least mine, measures 56 mm. The top of the stanchion enters the upper triple clamp at 55 mm diameter, but the diameter at the top of the tube seems to be 54 mm, like the stanchion necks in one mm at the very top. Is this true? And did the tube fit the lower clamp without a sleeve or did you have to sleeve it for both triple clamps?
You have the wheels turning now.
 

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The OD of the OEM fork legs aren't as straight as they appear. For my second try on custom clamps (new guy...long story). I'm sure he can turn and sleeve the forks, if you need this. When measuring the new fork legs one had a swing of 1mm, the other 3mm and +/- along the clamping length. They could have done better, but I guess saving a bit of time to meet the price point was the priority.

The carrier for the damper leg can be cut to accept a cartridge. This would be a significant improvement. It won't be adjustable, but unless racing at different tracks or changing riders, do you need to adjust it?
 

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Oh-oh ! Ok, I know I should not ask this question but who did the machine work for you? I may do this yet. Oh, big question, did the Brembo's line up properly on the stock rotors? And did the fender mounting points work with the stock R fender bracket?
I had my trusty caliper out today at a dealership (Santa Barbara HD, see my other post in V-Rod General) and there was an XR for me to measure. What I saw was the outer diameter of the stanchion tube was 55 mm while that of the Street Rod, at least mine, measures 56 mm. The top of the stanchion enters the upper triple clamp at 55 mm diameter, but the diameter at the top of the tube seems to be 54 mm, like the stanchion necks in one mm at the very top. Is this true? And did the tube fit the lower clamp without a sleeve or did you have to sleeve it for both triple clamps?
You have the wheels turning now.
Philthy, My old Hensley lathe is not tight enough for this kind of work, so I took it to a friend of mine who works at EW Corp, an Ario space machine shop. As for the Brembo rotors lining up, I don't think that there is any problem, but I can't say for sure as my composite rotors have been on backorder from Swan composites for 3 months. Tom says for sure they will ship next week. We hope so. The R fender mounts up fine, I however am using an F front fender. I made up some Ti brackets, as the stock F brackets are boat anchors. The way I remember it, the top clamp mounting surface of the X fork is about 1MM or so smaller than that on the R, it then tapers down another 1 or 2MM between the upper and lower mounting surfaces, and then tapers back up, so that it is the same diameter as that on the R, only not in the right spot for the lower clamp mounting surface, it then tapers down again, to the bottom of the tube. I tried to explain earlier, although I admit, not vary eloquently, when the X fork is fitted correctly in the R clamps, the top clamp is way to lose, and the bottom clamp is sitting mostly on the tapered area below the intended mounting pad. I could not see any other way to have an acceptable outcome other than to sleeve the whole tube from the top, down to where the bottom of the lower R clamp would sit. I also cut the bottom of my sleeves to exactly match the angle of bottom of the R clamps. I will post some pics on Monday. Hopefully you can think up something much easier. Ed...
 

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The OD of the OEM fork legs aren't as straight as they appear. For my second try on custom clamps (new guy...long story). I'm sure he can turn and sleeve the forks, if you need this. When measuring the new fork legs one had a swing of 1mm, the other 3mm and +/- along the clamping length. They could have done better, but I guess saving a bit of time to meet the price point was the priority.

Wow, I did not find anywhere near that much deviation from the spec's on the R or the X forks Ed... The carrier for the damper leg can be cut to accept a cartridge. This would be a significant improvement. It won't be adjustable, but unless racing at different tracks or changing riders, do you need to adjust it?
Well yes, it would be a significant improvement over the stock R fork, but it's really a pain to get it right with out being able to externally adjust it. but I suppose if you take it apart enough times you can get just about anything right. Still IMHO it will not dampen like the X Big piston fork will. Ed...
 

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Ok, I had an XR-1200X and my R side by side in a dealer shop with a micrometer and tape measure. The length of the XR-1200's steering neck is much shorter than that of a Street Rod's. This means the upper and lower clamps or the R are about 15 mm further apart than an XR-1200's. The diameter of the stanchion tubes on the XR-1200X narrow down between the triple clamps, so where the triple clamps grip the stanchion tubes is critical. That problem alone makes the conversion something other than a straightforward swap.
Next, while the diameter of the XR-1200X stanchion is the same as that of the R in the lower clamp, 56 mm, it is about 2 mm narrower at the top where it fits into the upper triple clamp. The free length of the fork leg is about 50 mm (2 inches) longer than the R's. The angle of the R's triple clamps to the fork tube makes determining where everything would line up installed in the R triple clamp difficult to do.
It is definitely not a simple bolt on, so now I can sleep well at night, LOL.
My next question is how hard it would be to transplant the BPF guts, sliders and lower fork legs into the R's stock stanchion tubes? Ah, now that is another interesting question. I may need to give Race Tech a call on Monday.
 

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The axle carriers look the same, but are they? I don't know how a BPF works or mounts. Is it like the cartridge?

Are the bottom of the axle carriers on the XR drilled to mount the guts. Only the cartridge axle carrier is drilled on the R. It isn't hard to counter bore and drill it, but getting there is a lot of work.

Keep us posted on what Race Tech says about upgrading.
 

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The axle carriers look the same, but are they? I don't know how a BF works or mounts. Is it like the cartridge?

Are the bottom of the axle carriers on the ZR drilled to mount the guts. Only the cartridge axle carrier is drilled on the R. It isn't hard to counter bore and drill it, but getting there is a lot of work.

Keep us posted on what Race Tech says about upgrading.
The casting is similar but not quite the same the same as the "R". The "R" axle fits fine in to the X forks. As to what it looks like in side, I don't know. Tony at Race tech could answer this question as he has disassembled and reassembled mine recently. Ed...
 

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Ok, I had an XR-1200X and my R side by side in a dealer shop with a micrometer and tape measure. The length of the XR-1200's steering neck is much shorter than that of a Street Rod's. This means the upper and lower clamps or the R are about 15 mm further apart than an XR-1200's. The diameter of the stanchion tubes on the XR-1200X narrow down between the triple clamps, so where the triple clamps grip the stanchion tubes is critical. That problem alone makes the conversion something other than a straightforward swap.
Next, while the diameter of the XR-1200X stanchion is the same as that of the R in the lower clamp, 56 mm, it is about 2 mm narrower at the top where it fits into the upper triple clamp. The free length of the fork leg is about 50 mm (2 inches) longer than the R's. The angle of the R's triple clamps to the fork tube makes determining where everything would line up installed in the R triple clamp difficult to do.
It is definitely not a simple bolt on, so now I can sleep well at night, LOL.
My next question is how hard it would be to transplant the BPF guts, sliders and lower fork legs into the R's stock stanchion tubes? Ah, now that is another interesting question. I may need to give Race Tech a call on Monday.
Yep, thats pretty much what I was trying to say. Your idea of swapping the guts into the "R" forks is an intriguing one. I hope you will keep us posted on what you find out. Ed...
 
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