cbrxxquad Posted May 6, 2012 Share Posted May 6, 2012 Yep same bearings.... Quote Link to comment Share on other sites More sharing options...
Skull Posted May 7, 2012 Share Posted May 7, 2012 Have I mentioned,,,,that I think an 2000 / 2001 Sp1 RCV 51 tree may be an exact replacement for the xx frame to zx14 fork using the same stock bearings and key? And all in all, may be cheaper new? Maybe I did,, For those looking, it's the RVT1000R: Steering stem, part number 53219-MCF-D00 - PartsFish: $328.39 - Service Honda: $273.12 Top bridge, part number 53300-MCF-670 - PartsFish: $185.65 - Service Honda: $170.59 The LSL kit is $500+ but I would only need the steering stem. I'll take a bath on the ZX14 LSL kit I already have, so I'm going to pursue the adaptor, but for anybody doing this in the future, the RVT triple clamp looks like the right solution. Quote Link to comment Share on other sites More sharing options...
IcePrick Posted May 7, 2012 Author Share Posted May 7, 2012 Anybody have a 929 or 954 triple to measure? The bearing sizes are the same as the XX, and I believe the fork diameter is correct for the 14's forks. My concern is the stem length and the "drop" that the 929/954 upper bridge has. There has been discussion on one of the RC forums that the 929 upper will swap with a SP1... I am clueless on the remainder of the geometry variables and how it would affect the XX. A little help from the experts? Quote Link to comment Share on other sites More sharing options...
Redbird Posted May 8, 2012 Share Posted May 8, 2012 Less offset= more trail. More trail= more stability. The opposite applies as well. Obviously more stability is going to mean slower steering. You're not going to affect rake (beyond potentially dropping or raising the front*) with any OEM triples I'm aware of. *It might be too late, and someone else can always get the number, but I'd suggest getting a stock front ride height number- bottom of the steering tube (frame) to center of the axle with the suspension fully extended. I think the 14 forks are shorter and it'd be nice to know how much you've moved things if/when you have to chase any setup issues. Hobie has a 929, try pinging him for measurements there. Anyway, I think we need a sticky with everyone's front end swap info and insights. All you guys that have done or are doing the mod should put together a no bullshit, info only thread and I can move it to the useful threads section. Quote Link to comment Share on other sites More sharing options...
IcePrick Posted May 8, 2012 Author Share Posted May 8, 2012 Some of the dudes on Fireblades.org are saying that the RC51 SP1 offset and tube diameter are identical to the 929/954. The CBR's fork tubes are shorter, thus the "dropped" upper bridge. If the RC51 SP1 upper bridge fits the ZX14's tube diameter and spacing (but not the offset, which required modification if I read that correctly), does it automatically follow that the entire RC and/or 929/954 triple would likely fit? I found someone claiming that all flavors of the RC have a quarter inch shorter stem than the 929/954, though the 02 and up RC had a larger stem diameter (up top only, I think). That doesn't tell me anything about the overall length of either, though. Thanks for the offset/trail primer for the simple man! Quote Link to comment Share on other sites More sharing options...
cbrxxquad Posted May 8, 2012 Share Posted May 8, 2012 I am pretty sure the total length of the forks, center-line axle to top of tube unloaded are very close on the zx 14, and busa. Maybe, 3/8 to 1/2 inch shorter, which is kinda lost in the whole setup equation. Also, I think you might be backwards on the offset thing, Tim, I have seen some pretty far offset cruiser trees, and tight racers. I ended up with the same rake as the bird, with everything set in the middle of the adjustment. I was trying to see, when I put it together, some relative point between the two to go from, so as to compare. And I left the bottom tree as it was on the zx forks when I put it together. So, the bottom bearing race, top edge, is what I found to be the only common dimension. As every thing else went together from that, all the differences showed up. Measuring some spot afterwards, that was common, left me with the resulting difference. That is what got me to the post asking for input in the dimension from the ground to the leading edge of the lowest faring right behind the front wheel with the bike on the center stand, unloaded like that left very little variation other than spring preload. but, after riding the bike and adjusting the preload with different conditions like no luggage, both side boxes, with top box, and passenger, and all the combinations., Tight twisties to long straight slabs. How it feels turning in, and holding the corner, and picking back up. I have found that without any lift in the back from a shim, I like the front 1/2' to 3/4 lower than stock to get the adjustment to one turn either way for the differences in load and road. If the 929 and 954 are exact replacements for the rc, hell they are cheap. Quote Link to comment Share on other sites More sharing options...
Redbird Posted May 8, 2012 Share Posted May 8, 2012 Also, I think you might be backwards on the offset thing, Tim, I have seen some pretty far offset cruiser trees, and tight racers. Cruisers are a different world and do some odd things with offset to compensate for other odd things done with rake, which is sometimes not even the same angle as the steering head- something you will rarely, if ever, see in a sportbike. Look at the picture and tell me what happens when you increase or decrease offset- Quote Link to comment Share on other sites More sharing options...
cbrxxquad Posted May 8, 2012 Share Posted May 8, 2012 Trail The relationship between head angle, rake and trail in a bicycle Trail, or caster, is the horizontal distance from where the steering axis intersects the ground to where the front wheel touches the ground. The measurement is considered positive if the front wheel ground contact point is behind (towards the rear of the bike) the steering axis intersection with the ground. Most bikes have positive trail, though a few, such as the two-mass-skate bicycle and the Python Lowracer have negative trail.[6] Trail is often cited as an important determinant of bicycle handling characteristics,[7][8] and is sometimes listed in bicycle manufacturers' geometry data, although Wilson and Papodopoulos argue that mechanical trail may be a more important and informative variable.[9] Trail is a function of head angle, fork offset or rake, and wheel size. Their relationship can be described by this formula:[10] where wheel radius, is the head angle measured clock-wise from the horizontal and is the fork offset or rake. Trail can be increased by increasing the wheel size, decreasing or slackening the head angle, or decreasing the fork rake or offset. Trail decreases as head angle increases (becomes steeper), as fork offset increases, or as wheel diameter decreases. Motorcyclists tend to speak of trail in relation to rake angle. The larger the rake angle the larger the trail. Note that, on a bicycle, as rake angle increases, head angle decreases. Trail can vary as the bike leans or steers. In the case of traditional geometry, trail decreases (and wheelbase increases if measuring distance between ground contact points and not hubs) as the bike leans and steers in the direction of the lean.[11] Trail can also vary as the suspension activates, in response to braking for example. As telescopic forks compress due to load transfer during braking, the trail and the wheelbase both decrease.[12] At least one motorcycle, the MotoCzysz C1, has a fork with adjustable trail, from 89 mm to 101 mm.[13] [edit]Mechanical trail Mechanical trail is the perpendicular distance between the steering axis and the point of contact between the front wheel and the ground. It may also be referred to as normal trail.[11] Although the scientific understanding of bicycle steering remains incomplete,[9] mechanical trail is certainly one of the most important variables in determining the handling characteristics of a bicycle. A higher mechanical trail is known to make a bicycle easier to ride "no hands" and thus more subjectively stable, but skilled and alert riders may have more path control if the mechanical trail is lower.[14] Yeah, learning a lot... Rake Angle And Steering Trail Causes Self-correction By: James R. Davis We will look at two things that result from the fact that your front forks are not pointing straight down - that is, there is a rake angle to those forks: how counter-steering is initiated and how weave and wobble are diminished. The diagram above represents your front tire pointing to the left. The diagonal dashed line represents your steering stem as if it were extended to the ground. Please note how this defines ground trail. (The diagram exaggerates how far forward of the contact patch the steering axis point is for clarity.) When you turn the handlebar you are attempting to turn the tire about the steering axis at ground level, not about the contact patch. For example, if you turn the handlebar to the right you are trying to get the tire to turn as shown above. However, as the contact patch is touching the ground and the axis is not, the contact patch CANNOT simply slide off to the left as shown. Instead, the body of the motorcycle moves in that direction via force at the triple-tree. You have, in effect, steered the front tire out from under the bike by steering the bike away from the tire. [At a dead stop turn your handlebars all the way to the right and observe how the top of the bike has moved to the right.] As a result, gravity now tries to pull the bike down towards the left and that drags the front wheel with it and our travel direction has begun moving to the LEFT. (For the purists out there this is not arguing that gyroscopic precession didn't play a part - only that because there is a rake angle counter-steering would work even without gyroscopic precession.) [Note that because of the huge difference in mass between the relatively light front-end and the rest of the bike, when traveling at less than about 6 MPH you actually CAN make a significant turn of the handlebars and there is not enough centrifugal force to push the top of the bike away from the direction you are pointing to. Instead, the bike falls INTO the turn at these slow speeds and THAT is why counter-steering does not work at such slow speeds.] Wobble and weave are diminished because when the wheel is pointing at an angle other than straight ahead the contact patch is not in alignment with the direction of travel of the bike - that is, a slip angle is created. A restoring force is applied to the contact patch by the ground which attempts to force that alignment. Thus, because of trail, the front wheel tries to go in a straight line. [This restoring force, sometimes called a 'righting moment' or 'castor effect', is a function of the length of trail. The longer the trail, the stronger it is. It is also a function of traction. The higher the traction, the stronger it is. Thus, braking increases the restoring force. This is primarily what 'dumps' a bike when the front brake is applied during a slow speed turn.] link I really want to study the geometry of countersteering Quote Link to comment Share on other sites More sharing options...
jon haney Posted May 8, 2012 Share Posted May 8, 2012 :icon_popcorn: If you guys get this down to a bolt-on affair with no welding or machining (except spacers), I will start ordering parts. I wish I had time to do this kind of research. Quote Link to comment Share on other sites More sharing options...
IcePrick Posted May 8, 2012 Author Share Posted May 8, 2012 :icon_popcorn: If you guys get this down to a bolt-on affair with no welding or machining (except spacers), I will start ordering parts. I wish I had time to do this kind of research. RC51 SP-1 and CBR929/954 look promising for a bolt-on triple. I have an SP-1 top bridge, once I find out if the stem length of either donor is the correct size, I'll order one up. Also have the option of pressing out the BB stem and installing it in an RC/CBR lower, if the diameter is the same. The major difference between the CBR and RC is the RC has a flat upper, while the CBR has a flat lower. The upper on the CBR is like an upside-down gull-wing, as the fork tubes are shorter. On the RC, the lower is like an upside-down gull-wing, as the ram air ducts pass between the fork tubes and steering head (so I'm told). The steering stops may be worthless on the RC, perhaps some minor advantage to having the longer grip length (distance between upper and lower triples) on the RC vs. CBR. I don't know why either upper or lower would interfere with the XX's acoutrements. Index of the key lock will be the next challenge. Hobi is going to measure his 929's stem. We'll finally know the size of Hobi's shaft! According to the info I have, the 1000RR is also a candidate... good eye Red... ummm... eye. Quote Link to comment Share on other sites More sharing options...
RedEye Posted May 8, 2012 Share Posted May 8, 2012 *It might be too late, and someone else can always get the number, but I'd suggest getting a stock front ride height number- bottom of the steering tube (frame) to center of the axle with the suspension fully extended. Suspension fully extended isn't a useful measurement with the ZX-14's soft top-out progressive springs. It only takes a few lbs to compress the forks for the first 15-20mm of travel; if you try to set sag using a fully extended measurement as your starting point, you're gonna have a bad time because unless you weigh 500 lbs you'll never get it down to 35mm rider sag. That's why they recommend just using a zip tie on the fork leg, riding the piss out of it and adjusting preload until you have 10-15mm of travel in reserve. Measuring frame to axle with the wheel on the ground, bike weight only, might be a better baseline. Quote Link to comment Share on other sites More sharing options...
RedEye Posted May 8, 2012 Share Posted May 8, 2012 According to the info I have, the 1000RR is also a candidate... good eye Red... ummm... eye. As far as I know the pre-08 (or whatever year they changed the stem bearing size) 1000RR front end is a straight swap to the 929 and 954. "Any pre-08 Fireblade" makes for a nice pool of donor bikes Since I've already rendered my ZX-14 top triple useless for other applications by modding the ignition mount I'll stick with the setup I have for now, but the info will be handy when I do my '86 Viffer and V45 Sabre. With the triples issue hopefully solved, now we need a comprehensive list of USD forks with the right length, preferably with radial brakes and fully adjustable. Busa and ZX-14 obviously work. Concours 14 probably also, will be heavier sprung and less adjustable. Triumph Tiger 1050 might be a candidate. I'll do some more research when I have time. Quote Link to comment Share on other sites More sharing options...
IcePrick Posted May 8, 2012 Author Share Posted May 8, 2012 Good info regarding the tube diameter, offset, etc. of various manufacturers/models here: https://docs.google.com/spreadsheet/ccc?key...=CPyf0pkD#gid=0 The attached spreadsheet here: http://www.vfrdiscussion.com/forum/index.p...em/#entry746461 And: http://www.dotheton.com/forum/index.php?topic=5669.0 No mention of stem dimensions anywhere, though. And again, lining up the key switch will be pure voodoo until the uppers are each in hand. Quote Link to comment Share on other sites More sharing options...
Redbird Posted May 8, 2012 Share Posted May 8, 2012 Suspension fully extended isn't a useful measurement with the ZX-14's soft top-out progressive springs. It only takes a few lbs to compress the forks for the first 15-20mm of travel; if you try to set sag using a fully extended measurement as your starting point, you're gonna have a bad time because unless you weigh 500 lbs you'll never get it down to 35mm rider sag. That's why they recommend just using a zip tie on the fork leg, riding the piss out of it and adjusting preload until you have 10-15mm of travel in reserve. Measuring frame to axle with the wheel on the ground, bike weight only, might be a better baseline. I wasn't suggesting that measurement as a baseline for sag, but a baseline for ride height so any changes there can be quantified. Sag and ride height are two different things. Related, yes, but different. Quote Link to comment Share on other sites More sharing options...
IcePrick Posted May 8, 2012 Author Share Posted May 8, 2012 Stock XX stem is ~220mm. The ZX14 stem looks to be around 250mm - difficult to be exact when mounted. Quote Link to comment Share on other sites More sharing options...
RedEye Posted May 8, 2012 Share Posted May 8, 2012 My point was, if you measure with the wheel off the ground (which is what I assume you meant when you said front suspension fully extended), you'll be measuring an extra 20 or so mm of suspension travel that you only get with the front end unloaded or nearly so. That extra travel is to keep the front wheel in contact with the ground under hard acceleration and the only contribution it makes to ride height is the length of that topout spring when it's fully compressed, which takes only a small fraction of the bike's weight and can't be measured anyway. But even without soft top-out springs, I don't see how the fully extended measurement is useful for comparing ride height. Quote Link to comment Share on other sites More sharing options...
Redbird Posted May 8, 2012 Share Posted May 8, 2012 How do you adjust ride height? By lengthening or shortening the shock (done via shims on OEM or non-adjustable shocks) and raising/lowering the forks in the triples. If you're going with a completely different front end, it might be helpful to know where you started and where you end up, as even a .25" difference in distance between the axle and the frame can be felt, everything else (sag, spring rate, etc.) being equal. Quote Link to comment Share on other sites More sharing options...
redxxrdr Posted May 9, 2012 Share Posted May 9, 2012 I may be way off here, but I always thought that adding the 6mm shim, or dropping the forks in the triples changed the rake of the bike. I think it's 25 degrees on a stock XX. Less angle to make a faster turning bike. So, Couldn't a rake measurement be used for a good starting point for the front forks? You would need a known flat surface and a good digital angle scale to do the test. Measure stock, or with the 6mm shim, and work from there. SAG, should be set for bike and rider weight. Adjusted to set the suspension in the useful range. You could then raise or lower the forks/rear shock to get a useable rake without getting to the point of head shake. I have read that top out springs will confuse the standard SAG settings, so I would follow the ZX14 forum suggestions.. I suspect the zx14, like the GSXR change for my SV would come with a steering dampner, allowing steeper head angles without becoming unstable. I will try this theory if I ever get around to doing the SV. I have a inclinometer that reads down to minutes, It will be my guide. I bet I will see rake changes when replacing springs for my weight, tire types, tire pressures, and our standard rear shock shim. Quote Link to comment Share on other sites More sharing options...
cbrxxquad Posted May 9, 2012 Share Posted May 9, 2012 Alright, I got just a minute. The point to having a starting point is to try to get relative. Not setup the bike. That is something else. The numbers mean nothing but where in the tree to start. You only have so much to play with. And then there you are. I ran it at both extreme just to see. Both stock location of the forks in the bottom tree, and all the way as low in the tree as it will go. At the stock location of the bottom tree in the 14 forks, the lowest you can install the top tree, the forks stick out of the 14 bars even with risers. And the unloaded measurement of the coweling to ground was about the same. The rake was too. + or _ a degree from the stock xx. It sets the length of the forks in the trees to something like the xx. Because the neck of the 14 is much longer, but the location of the top of the bottom bearing race is about the same as the xx in this way. more later, dinner..... Quote Link to comment Share on other sites More sharing options...
IcePrick Posted June 15, 2012 Author Share Posted June 15, 2012 Lo and Behold, there was a CBR929 lower triple on my front porch step this evening when I got home. Initial measurements looks like it is very close to the XX's stem length. I'll have to test fit it to see if the existing steering stops will interfere or if they will have to be removed. The RC51 SP1 upper clamp I picked up a while ago isn't very pretty, but it will work to see if everything fits - the eyeball gauge says it should bolt up. :icon_think: Anybody have a suggestion for tapered bearings for a 929? Hopefully some progress this weekend... Quote Link to comment Share on other sites More sharing options...
IcePrick Posted June 17, 2012 Author Share Posted June 17, 2012 Stan is THE man!!! 929/954 lower, RC51 SP1 upper, all the XX bearings are the same. Stem is a *tad* longer, but bolts up fine and the threads don't extend irregularly from the 929 upper clamp nut. Bearings tightened down fine. Now I have to beg someone for some ride height measurements, as I lost the piece of paper I wrote my "before" measurements on. If you saw my garage, you'd understand. The existing 929 steering stops hit the bracket mount at the front of the XX steering head. Shaving them down will be necessary, and I was hoping that I could shave them only slightly and make them the new stops against the bracket mounting point cast into the steering head - but I don't think it will allow enough travel, and it may be too weak to handle a tipover. Out to balance the front wheel, then I have to clean up as I have company coming... Bottom line, the ZXXX is nearly a bolt-on, with just some minor machine work (Dremel) and some eBay shopping. Quote Link to comment Share on other sites More sharing options...
cbrxxquad Posted June 17, 2012 Share Posted June 17, 2012 Stops can be made that bolt on the frame to stop at any distance required. Good idea too, just saying. Setup, I start with the bike on the centerstand and measure the bottom of the front of the body work to ground, or just live with what I have. Sticking out as far as I have with what I got, as tall as possible. Safe.. Tie wrap around the fork tube and ride like I stole it. Measure the actual movement from seal to tie wrap, and set sag at 30% with me on the bike ballenced including all gear and baggage. Set the rear, and set the front. Put the compression and rebound in the middle on all. Then bitch and adjust till nothing to bitch about. Front and rear should move the same in a bump, or when you push down on the seat. I have star wheels on the front preload for when I am slabing, loaded with bagage, twisties with and without bags. Each winter I go back to the center with everything. Each spring makes me if I didn't. Savie? Quote Link to comment Share on other sites More sharing options...
Skull Posted July 7, 2012 Share Posted July 7, 2012 Well, shit. This is a better solution than the machined bearing cup, and it's going to cost me a lot of money. Thanks for nothing, Mike. Quote Link to comment Share on other sites More sharing options...
IcePrick Posted July 7, 2012 Author Share Posted July 7, 2012 Well, shit. This is a better solution than the machined bearing cup, and it's going to cost me a lot of money. Thanks for nothing, Mike. Sorry!!! Maybe sell your triple on .com? I got the RC51 upper for $25 on ebay... the 929/954 lower was about $175 though, I think (ebay also). The next project, which I might skip entirely, is roller bearings as opposed to the existing ball bearings I re-used from the 929 triple - they were in fine shape, though. I've had a bunch of other projects that have snuck in front of this one, so I haven't done steering stops or tried out the key switch alignment yet. I swore that was going to be this week, but a TW200 refresh for a friend became more complex, as always. Maybe I can manage some time tomorrow morning. That's as close to bolt-on as I think it's going to get - I would like to see an SP1 lower and how that fits with the steering stops before I make the lofty claim that the 929/954 lower triple is THE way to go. I wouldn't mind trying a 929/954 upper either, just to see how it looks. For now, I've invested enough in parts that are laying around the garage never to be used... the cost of "research". Quote Link to comment Share on other sites More sharing options...
Skull Posted July 7, 2012 Share Posted July 7, 2012 Well, shit. This is a better solution than the machined bearing cup, and it's going to cost me a lot of money. Thanks for nothing, Mike. Sorry!!! Maybe sell your triple on .com? I got the RC51 upper for $25 on ebay... the 929/954 lower was about $175 though, I think (ebay also). The next project, which I might skip entirely, is roller bearings as opposed to the existing ball bearings I re-used from the 929 triple - they were in fine shape, though. I've had a bunch of other projects that have snuck in front of this one, so I haven't done steering stops or tried out the key switch alignment yet. I swore that was going to be this week, but a TW200 refresh for a friend became more complex, as always. Maybe I can manage some time tomorrow morning. That's as close to bolt-on as I think it's going to get - I would like to see an SP1 lower and how that fits with the steering stops before I make the lofty claim that the 929/954 lower triple is THE way to go. I wouldn't mind trying a 929/954 upper either, just to see how it looks. For now, I've invested enough in parts that are laying around the garage never to be used... the cost of "research". I can probably get ~$200 for the ZX14 LSL top triple which means only an additional ~$350 for the RC51 LSL top triple. :icon_wall: Quote Link to comment Share on other sites More sharing options...
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