04 Fork Replacements

[didit]

Watching this thread closely as I'll have to change my fork fluid this off season and had a recomendation from choco to change out the springs (and parts) for a set up more suited to the rider (me - at 240lbs).

He had good luck with RaceTech parts, but a challenge with the installation service.

As I too am planning on keeping my current bike and always look to improve (cost effectively) can ya'll suggest the best parts replacement

"WITHOUT" completely changing the forks? Links and service recommendations appreciated.

I would prefer a manufacturer brand rather than a different model setup, to minimize / eliminate any wheel, body or break modifications.

[Baileyrock]

OK, so to summerize the "What to look for" parts when swapping the whole front end...it comes down to this:

...Jimmy offered a list:

CBR600RR

CBR1000RR

CBR954RR

CBR929RR

RC51

Of this list, I think only the RC51(sp1) forks are long enough to be a suitable swap! :beer:

[JamieDaugherty]

Watching this thread closely as I'll have to change my fork fluid this off season and had a recomendation from choco to change out the springs (and parts) for a set up more suited to the rider (me - at 240lbs).

He had good luck with RaceTech parts, but a challenge with the installation service.

As I too am planning on keeping my current bike and always look to improve (cost effectively) can ya'll suggest the best parts replacement

"WITHOUT" completely changing the forks? Links and service recommendations appreciated.

I would prefer a manufacturer brand rather than a different model setup, to minimize / eliminate any wheel, body or break modifications.

I used to install RaceTech springs now I use Sonic Springs. They're a bit cheaper but just as good on quality. Plus I can get special rates and still be able to offer them for $85 installed. Have no fear with using them.

I think just revalving the stock forks is a great way to go. There are advantages to using inverted forks off something else, but for most street riders making improvements to the stock forks gets them plenty of performance. A proper suspension setup goes a long way to improving control, performance, and overall riding enjoyment. I've been installing both RaceTech and Ohlins valves and would say that either would work well for you. As a street rider, I'd suggest going with the RaceTech compression valves only and reshimming the stock VFR rebound valves. That's the most cost effective way to get a big performance increase.

It's not really been discussed here (and it's probably a thread jack) but revalving and respringing the stock VFR shock results in performance gains that would surprise many. Luckily for us there are lots of options and it really depends on what you want and how much you have to spend. You don't necessarily need to look at parts from other bikes to get what are after. It's when you want 'more' that getting technology from other bikes becomes helpful.

[marid2apterbilt]

QUOTE (Tightwad @ Sep 14 2009, 04:20 PM)

OK, so to summerize the "What to look for" parts when swapping the whole front end...it comes down to this:

...Jimmy offered a list:

CBR600RR

CBR1000RR

CBR954RR

CBR929RR

RC51

Of this list, I think only the RC51(sp1) forks are long enough to be a suitable swap! :fing02:

As I have tried some pretty drastic changes in the geometry of my bike, Raise/lower front/rear just to see the effects.. IMHO I wouldnt use any forks that are over 1" shorter without seriously considering a steering dampner also.. Tank slappers are not fun..

[Baileyrock]

I've been installing both RaceTech and Ohlins valves and would say that either would work well for you. As a street rider, I'd suggest going with the RaceTech compression valves only and reshimming the stock VFR rebound valves. That's the most cost effective way to get a big performance increase.

JD, aren't there HUGE differences between Race Tech & Ohlins valves alone???

From what I've seen the Ohlins valves use Much smaller ports, much closer to stock Honda valves than the open(huge)

racetech valves! Is that still the case?

I am no suspension expert whatsoever, but I've heard many experts talk about racetech ports being so large that they no longer perform one aspect of suspension dynamics and that that function is now moved to being controlled by the shim stack adding to it's load and limiting the ability to compensate for it? :huh:

Since you use both valves in your builds, do you have to run drastically different shim stacks from one valve to the other and is it still true that the Ohlins ports are much smaller and closer to stock size than race tech valves?

It seems that race tech has a much different philosophy than Ohlins when it come to valves & valving! :mellow:

To me, if prices were similar or even close I would always choose Ohlins products over race teck. Not that you can't improve performance or feel with Rt products, but I consider Ohlins to be the Top if not one of the best suspension company's in the World and would have to think their products were superior. :blush:

[SEBSPEED]

Kev, not sure which RT valve he's referring to, but the new RT G2R Gold Valve doesn't have the huge ports anymore, well - sort of. They allow for tuning of port size now:

http://www.race-tech.com/HTML_FILES/GVWHYGV.html

[Baileyrock]

Kev, not sure which RT valve he's referring to, but the new RT G2R Gold Valve doesn't have the huge ports anymore, well - sort of. They allow for tuning of port size now:

http://www.race-tech.com/HTML_FILES/GVWHYGV.html

:mellow:

Not huge ports???

There's almost no material there to slow oil flow! :blush:

[JamieDaugherty]

I've been installing both RaceTech and Ohlins valves and would say that either would work well for you. As a street rider, I'd suggest going with the RaceTech compression valves only and reshimming the stock VFR rebound valves. That's the most cost effective way to get a big performance increase.

JD, aren't there HUGE differences between Race Tech & Ohlins valves alone???

From what I've seen the Ohlins valves use Much smaller ports, much closer to stock Honda valves than the open(huge)

racetech valves! Is that still the case?

I am no suspension expert whatsoever, but I've heard many experts talk about racetech ports being so large that they no longer perform one aspect of suspension dynamics and that that function is now moved to being controlled by the shim stack adding to it's load and limiting the ability to compensate for it? :huh:

Since you use both valves in your builds, do you have to run drastically different shim stacks from one valve to the other and is it still true that the Ohlins ports are much smaller and closer to stock size than race tech valves?

It seems that race tech has a much different philosophy than Ohlins when it come to valves & valving! :mellow:

To me, if prices were similar or even close I would always choose Ohlins products over race teck. Not that you can't improve performance or feel with Rt products, but I consider Ohlins to be the Top if not one of the best suspension company's in the World and would have to think their products were superior. :blush:

Yes, there are noticeable differences in the design of the RaceTech and Ohlins valves. As such the shim stacks used are very different. Some of it is just like you describe - RaceTech uses very large ports so that the shim stack can control all of the damping curve. The problem comes in when you need more high speed but not as much mid-speed. Dual stage and preloaded stacks have been used for this in the past and those two offer ways to tune the damping. The G2-R valves allow you to actually adjust the port size opening, effectively being able to create a more restrictive flowing valve. All of the G2-R applications I've installed have used the ports wide open, for whatever that is worth. The G2-R valves also bend the shim differently which is more controlled. The standard Type I valves still work very well for both street and race applications. That's what I run in my personal bikes.

The Ohlins valves perform pretty well. I've found the RaceTech parts to have more adjustability which is something I like. Adjusting the shim stack on the Ohlins valves doesn't seem to have as much of an effect. The Ohlins valves ports are still bigger than stock, so it tells me that you want more flow. I guess it's a matter of how much you want the valve to control the high end of the shaft speed and how much you want the shim stack to control it. The extreme low end is controlled by the free bleed or external adjusters (if they exist). In between both the RaceTech and Ohlins valves seem to work about the same.

[JamieDaugherty]

Kev, not sure which RT valve he's referring to, but the new RT G2R Gold Valve doesn't have the huge ports anymore, well - sort of. They allow for tuning of port size now:

http://www.race-tech.com/HTML_FILES/GVWHYGV.html

:mellow:

Not huge ports???

There's almost no material there to slow oil flow! :blush:

That's a picture of the newest generation motocross valve. The G2-R fork valves look vey different. Here is what the fork valves look like:

[thx1139]

That's a picture of the newest generation motocross valve. The G2-R fork valves look vey different. Here is what the fork valves look like:

I've got some valves that look similar. Came in a set of junk FleaBay cartridges. Anyone have a copy of the setup instructions?

[SEBSPEED]

I've got some valves that look similar. Came in a set of junk FleaBay cartridges. Anyone have a copy of the setup instructions?

Pete McCrary(member here) has the new G2-R valves in his VFR, try asking him.

[vfrcapn]

OK, so to summerize the "What to look for" parts when swapping the whole front end...it comes down to this:

...Jimmy offered a list:

CBR600RR

CBR1000RR

CBR954RR

CBR929RR

RC51

Of this list, I think only the RC51(sp1) forks are long enough to be a suitable swap! :biggrin:

The SP2 forks are shorter but can still work, it takes a little more effort to dial the geometry in. If you're going to use superbike bars, the others should be long enough also.

[vfrcapn]

That's a fair enough point. The 2004+ R1 swap is definitely a simple one. As the R1 forks are normally spaced 210mm apart and the Honda triples space the forks 214mm apart you simply need a bunch of 2mm spacers per side, on either side of the OEM axle spacers, and between the rotors and wheel (as you can't space radial calipers).

Do you know the details on how the rotor spacing was handled? Zroyz didn't mention the details in his R1 swap write up but did mention the difficulty in this.

[JamieDaugherty]

That's a picture of the newest generation motocross valve. The G2-R fork valves look vey different. Here is what the fork valves look like:

I've got some valves that look similar. Came in a set of junk FleaBay cartridges. Anyone have a copy of the setup instructions?

I've got them. Shoot me an e-mail and I'll scan them to a pdf and shoot them your way.

[The Phantom]

That's a fair enough point. The 2004+ R1 swap is definitely a simple one. As the R1 forks are normally spaced 210mm apart and the Honda triples space the forks 214mm apart you simply need a bunch of 2mm spacers per side, on either side of the OEM axle spacers, and between the rotors and wheel (as you can't space radial calipers).

Do you know the details on how the rotor spacing was handled? Zroyz didn't mention the details in his R1 swap write up but did mention the difficulty in this.

You can either make ten separate 2mm spacers or two rings with five holes drilled in each one. I think Roy went with the latter while mine is the former. See pic below (which I'd forgotten I'd done). The text in the pic indicates that the ten separate spacers were too much of a PITA to use, but I've since fitted and removed them numerous times and they actually work just fine - once you have set all five onto the wheel, you carefully lower the rotor then drop the bolts in, and once the 'collar' part hits the spacer it centres and bites into it and gives it excellent positive location. When you remove the rotor you can actually turn each bolt out just far enough that it is held in place by the spacer to make it a piece of cake to reinstall.

Roy also managed to find longer rotor bolts but I haven't been able to - I have a set of brand new ones and there is still a lot of thread bite, so maybe they would be ok, but before mine gets to rideable stage I will be conferring with Roy.

As per the pic, I initially had my axle spacers made up incorrectly - the way they are depicted they would go inside the existing spacers. I've since had another pair turned down from a set of OEM spacers which use the larger OD section of the spacers, so they sit outside the existing spacers.