Another RC51 Front End Conversion (Fork Swap)
07-09-2009, 11:31 PM
#1
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Another RC51 Front End Conversion (Fork Swap)
Just finished the RC51 setup on my VTR. My goal was to make it look like it came that way from the factory, hopefully I've succeeded. Before mounting the legs I had to grind down the backside of the steering stops on the lower clamp to keep them from hitting the stay mount, then I added some allen bolts to the front-side of the stops to reduce full lock. Everything else was pretty much bolt on. I reused the All ***** steering head bearings, but ordered a new lower bearing and seal for the 954 clamp. There is a little more interference with the upper radiator hose than the stock setup, but I didn't move the radiators back at all. I'd like to take the radiators down to my favorite fabricator and see if he can angle the upper outlets inward. Overall turning radius will also be decreased, but hey, it sucks on the RC51 too. 
I definitely like how the color of the fork legs go with the engine covers, bonus! I've tried a few different clip on options; CBR954RR Helibars - too tall, Swatt's 2.5" rise - too tall, Vortex no rise - too short. I finally settled on a nice set of stock 954Rr clip on's mounted above the triple. The downward angle isn't all that great, but the rise is primo... everything just barely clears the fairing... they"ll do for now. Front fender was also painted to match (painted the inner fairings as well since they come unpainted from Honda on the '05's). Overall I'm very pleased with the setup, the front end feels rock solid in corners now. The rear now seems a little shakey... but I should be able to fix that with a few adjustments.
I definitely like how the color of the fork legs go with the engine covers, bonus! I've tried a few different clip on options; CBR954RR Helibars - too tall, Swatt's 2.5" rise - too tall, Vortex no rise - too short. I finally settled on a nice set of stock 954Rr clip on's mounted above the triple. The downward angle isn't all that great, but the rise is primo... everything just barely clears the fairing... they"ll do for now. Front fender was also painted to match (painted the inner fairings as well since they come unpainted from Honda on the '05's). Overall I'm very pleased with the setup, the front end feels rock solid in corners now. The rear now seems a little shakey... but I should be able to fix that with a few adjustments.
Last edited by inderocker; 05-12-2010 at 01:17 AM.
to the dark side indie... 
07-10-2009, 10:51 AM
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Thought I'd post my RC51 fork swap. Not too much to report as of yet, as I'm still waiting on my front rim to show up from Canada, which needs to be sent out for powder coating when it arrives. I also still need to find some suitable clip-on's, I'm thinking CBR954RR Helibars. My goal it to make it look like it came that way from the factory. I set up what parts I had today, just to make sure it was all gonna fit. I had to grind down the backside of the steering stops to keep them from hitting the stay mount, then I added some allen bolts to the front-side of the stops to reduce full lock. I also shimmed the upper triple to get the steering lock to work. It doesn't look like I'll have to move the radiators back at all, as there is only a little more interference with the upper radiators hose than the stock setup. Overall turning radius will also be decreased, but hey, it sucks on the RC51 too. I definitely like how the color of the fork legs go with the titanium, Bonus! I didn't spend too much time measuring to set it up correctly, but i will when it goes on to stay on.
I definitely like how the color of the fork legs go with the titanium, Bonus! I didn't spend too much time measuring to set it up correctly, but i will when it goes on to stay on.Cool... nice to see another RC setup.... and your right... you don't need to move the radiators unless your completly **** retentive (in other words if you need to know what's requried to move them, let me know!!!!)
If you have any questions along the way, LMK... I'm on my second RC swap already!!! This time I have some tricky triples though.... adjustable Attack Clamps.... they look awsome.
J.
07-13-2009, 10:53 PM
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Has anybody already done the swap with a SP1 forks/CBR954RR triple combination? If so, did you do the math figure out how far up the forks need to be in the triples to get it as close to the stock geometry as possible?
07-14-2009, 09:03 AM
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07-14-2009, 09:10 AM
#13
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irocker, I used CBR954 triples which push the legs down quite a bid since the 954 legs are even shorter than the RC51 SP2s it work's perfectly
https://www.superhawkforum.com/forum...rc51+fork+swap
https://www.superhawkforum.com/forum...rc51+fork+swap
07-14-2009, 09:35 AM
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Off hand.... I think I have my forks (SP1) 17mm above the triple... measured at the top of the fork tube, below the fork cap. I'm running a RC51 upper, which is flat, and I believe the 954 triple has a 12-13mm drop (in the gullwing area)... therefore your looking at 29-30mm from tree to top of fork tube (not counting the cap).
I can verify my dims tonight... I got the measurement from another member who did the swap as well, and I haven't moved the forks since... (I think I got it from RCVTR)
You'll find that this measurement will leave just enough of the fork exposed to **** you off as I found it was about 5mm short of being able to mount my clipons above the triple!!!! That's why I went with the RC upper in the end.
J.
I can verify my dims tonight... I got the measurement from another member who did the swap as well, and I haven't moved the forks since... (I think I got it from RCVTR)
You'll find that this measurement will leave just enough of the fork exposed to **** you off as I found it was about 5mm short of being able to mount my clipons above the triple!!!! That's why I went with the RC upper in the end.
J.
07-14-2009, 09:38 AM
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irocker, I used CBR954 triples which push the legs down quite a bid since the 954 legs are even shorter than the RC51 SP2s it work's perfectly
https://www.superhawkforum.com/forum...rc51+fork+swap
https://www.superhawkforum.com/forum...rc51+fork+swap
I noticed with the 954 triples that the fatter part of the SP2 leg was too low for the clamp . The fat part of the SP1 legs come up much further.
07-14-2009, 12:04 PM
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Off hand.... I think I have my forks (SP1) 17mm above the triple... measured at the top of the fork tube, below the fork cap. I'm running a RC51 upper, which is flat, and I believe the 954 triple has a 12-13mm drop (in the gullwing area)... therefore your looking at 29-30mm from tree to top of fork tube (not counting the cap).
I can verify my dims tonight... I got the measurement from another member who did the swap as well, and I haven't moved the forks since... (I think I got it from RCVTR)
You'll find that this measurement will leave just enough of the fork exposed to **** you off as I found it was about 5mm short of being able to mount my clipons above the triple!!!! That's why I went with the RC upper in the end.
J.
I can verify my dims tonight... I got the measurement from another member who did the swap as well, and I haven't moved the forks since... (I think I got it from RCVTR)
You'll find that this measurement will leave just enough of the fork exposed to **** you off as I found it was about 5mm short of being able to mount my clipons above the triple!!!! That's why I went with the RC upper in the end.
J.
FYI
I think the SP2 difference in measured length is a bit of an artifact of the longer top out springs being used and thus sag is measure differently. In practice the effective length shoudl be about the same.
bc
07-14-2009, 12:49 PM
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What you do is with the old forks still on there, you remove the wheel and put the axle back on, and measure from the frame to the axle. Then when you put the new forks on you put the axle in and raise the forks in the triple till the axle is the same distance as you measured on the old forks.
07-19-2009, 08:02 PM
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Nice looking project! I also have a RC swap on my hawk, I too am using a RC51 upper and a 929/954 lower triple. I think that the TL1000 Heli's are some of the taller ones that Heli makes for our fork diameter!
Dennis
Dennis
08-22-2009, 01:28 AM
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As far as I know, nobody did any modifications to the radiators... I moved them back and down slightly following the lines of the fairing and then rotated the front hose a bit... Then added 2 mm to the steering stops which gave me nearly full lock without the forklegs hitting anything... Including the font hose and the fairing up around he handlebars...
08-22-2009, 04:47 AM
#24
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I just left the radiator hose in the stock location. The lower triple just barely touches and that is only at full lock. I'll be keeping an eye on it to see if there is any damage to the hose but after 1+ years of riding there is nothing yet.
08-22-2009, 06:39 AM
#25
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same. no effect after 3 years+
08-27-2009, 10:06 PM
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Well, I took her out to the "spars" for a little fun, but still found the rear-end acting like a wet noodle. For the most part, the bike was well planted with the Race Tech'd, stock legs, but now that the RC51 forks are on there the *** end is all over the place. When I did the swap, I measured from the bottom of the front axle to the bottom of the steering neck and got 29" ( I forget the measurement, but let's just say it"s 29"). I guesstimated another .25" shorter for the shorter triple offset and set the RC51 forks at 28.75".
I'm not sure what is causing the loose rear-end, but I'm pretty sure it has something to do with the forks since that's the only thing that's changed... it's like I'm riding around with a flat rear tire, but only when I'm in corners. I set the rear sag at 25 or 30mm a while ago, the front is set at 25mm. Should I drop the front end a little bit more, or is there something else I should be looking at? Suspension guru's, please chime in... Greg, Jamie, etc...
I'm not sure what is causing the loose rear-end, but I'm pretty sure it has something to do with the forks since that's the only thing that's changed... it's like I'm riding around with a flat rear tire, but only when I'm in corners. I set the rear sag at 25 or 30mm a while ago, the front is set at 25mm. Should I drop the front end a little bit more, or is there something else I should be looking at? Suspension guru's, please chime in... Greg, Jamie, etc...
08-28-2009, 03:48 AM
#28
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I'm guessing you have the stock damper? If so, that's the most likely culprit... In stock form it's either snatchy and harsh or like you said "wet noodle"...
And yeah, it was kinda bad before my swap... Once the swap was done it felt like two different bikes...
And yeah, it was kinda bad before my swap... Once the swap was done it felt like two different bikes...
08-28-2009, 05:33 AM
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In the meantime, I'd raise the front end if you do anything to get you more stability out back...a braced swingarm helps too...
