If I raised the rear end with adjustable dog bones to about a inch or so higher do I need a longer shock, if I recall I think I shortened the dog bones, they are the soupy adjustable dog bones, to raise the rear, so how would I measure to see how much longer I need the shock to be, thanks yall.
No need to get a longer shock. You might enjoy a new one though, if you are running a stock shock.
Klaus with hyperpro says I do, he's a builder for them here in the usa
He is wrong or confused by your request.
I thought so to, I told him that I have adjustable dog bones and raised it about an inch, he said measure the space between it and the ground while bike is on centerstand, then put old dog bones on and remeasure, and that would be the difference.
Measuring the gap from rear tire to ground
My guess is if I kept the soupy dog bone where there at now and got a shock one inch taller wouldn't that raise the rear even further, I think he is getting confused of me wanting to put my original dog bones on with the taller shock so I would still have the height I have now, maybe thats what he's getting confused about
Quote from: yambutt on February 03, 2016, 10:05:52 AM
Klaus with hyperpro says I do, he's a builder for them here in the usa
Do you *need* a longer shock? No.
Will a longer shock raise the back end? Yes.
Between the options of 1) shorter dogbones vs 2) longer shock, which option is better? Longer shock.
I think what Klaus is saying (and he is correct) is that the longer shock option is preferable over shorter dog bones because the longer shock keeps the swingarm linkage geometry stock as the engineers at Yamaha designed it.
When you shorten the dog bones the angles on the linkage (relay arm) change and the articulation of linkage is different which affects the compression/rebound characteristics of the shock and spring.
That said, many of us use shorter dogbones with no ill effects.
I use both options, longer shock (Penske) and adjustable dogbones.
I too have Soupy's adjustable links and I have a point of caution to warn you:
When you adjust the links, be *
absolutely sure* that each side is equal in length. I mean equal down to a nat's ass. If each side is even a milimeter different this will put an uneven load on the bearings in your swing arm linkage and you will ruin them is short order. Ask me how I know.
I set the rear height where I want it using only 1 adjustable link....then take that link off the bike and up to my work bench where I set the 2nd link equal to the first link. You must be precise.
I'm sure Klaus means well, but he is probably not familiar with the rear suspension on the FJ.
If yours has dog-bones, there is essentially TWO swing-arms on your FJ. One is the transfer arm, that connects the bottom of the rear shock to the frame. It's relationship to the frame, and the rear shock never changes. It simply moves up and down with the compression and rebound of the shock.
Then there is the swing-arm that the wheel is attached to. It is connected to the transfer arm with the dog-bones. By shortening or lengthening these dog-bones, you are changing the relationship between the swing-arm, and the transfer arm. This will raise or lower the rear wheel in relationship to the frame. The length of the shock has nothing to do with it.
It is possible to get the same result by altering the length of the shock, but most people alter the length of the dog-bones instead.
Not all FJs have dog-bones on the rear suspension. If I'm thinking correctly, it is the '89-up models. (Possibly '88 Jap and Euro models?)
The only way to raise the rear on the early ones is to lengthen the shock.
oops, Pat beat me to it. :good:
Early FJ
(http://i859.photobucket.com/albums/ab154/firehawk068/FJ1200/Early%20FJ_zps8f1gqpoy.jpg) (http://s859.photobucket.com/user/firehawk068/media/FJ1200/Early%20FJ_zps8f1gqpoy.jpg.html)
Later FJ
(http://i859.photobucket.com/albums/ab154/firehawk068/FJ1200/Later%20FJ_zpsyhtaesq2.jpg) (http://s859.photobucket.com/user/firehawk068/media/FJ1200/Later%20FJ_zpsyhtaesq2.jpg.html)
Thank yall all so much, I think I will go with the taller shock and put the original dog bones on, that to me seems the safest way....
Oh so if I go with taller shock and original dog bones should I then adjust chain back to 3/4 of a inch instead of the 1 1/4 I have now
Pat, sorry, I have to disagree and so does the company that manufactures the RPM shock for me.
The longer shock changes the relay arm linkage geometry to the shock affecting compression & rebound functions. That is why I do not offer an adjustable length shock as it changes the required valving within the shock.
Yes, the dog bone length does raise or lower the bike by changing the distance of the swing arm in relation to the relay arm which is the proper way to affect ride height changes, but it does not affect the shock valving or performance.
Just loo at the really long BMW shock that Fred installed prior to the RPM shock he has now, that is a drastic change to the relay are geometry and requires different valving to compensate.
(http://i119.photobucket.com/albums/o145/aviationfred/IMAG0213_zps84323542.jpg~original) (http://s119.photobucket.com/user/aviationfred/media/IMAG0213_zps84323542.jpg.html)
(http://i119.photobucket.com/albums/o145/aviationfred/IMAG0214_zps0bd81601.jpg~original) (http://s119.photobucket.com/user/aviationfred/media/IMAG0214_zps0bd81601.jpg.html)
Stock shock length is always better because the Yamaha geometry stays as designed.
Longer shocks only move the relay linkage down and out of the original geometry design...
Randy - RPM
Randy, yes there are extremes where a longer shocks can be detrimental.
I'm relaying advice I've been told by several motorcycle suspension experts.
Jim Lindemann (RIP) Ed Sorbo at Lindemann Engineering, and Donnie Jenkins at Traxxion Dynamics just to name a few.
In addition several shock manufacturers (Penske, Hagon, Ohlin, Fox) will also disagree with you.
So we know about the handling benefits of raising the back end of our bikes (I don't think there is disagreement there, correct?)
Randy, does this mean that your shock will *never* have the length adjustable feature so the folks who have the '84-87 FJ's (no dogbones) get the ability to raise the back end (like folks who enjoy the option on the '89-93 FJ's)
The Penske shocks have a 3/4" range of adjustment on the shaft of the shock....is that a really big deal? Really?
With respect: I think the opinion of your shock manufacturer is self serving.
Self-serving...yep bet your ass.
Sorry, I don't know Ed Sorbo or Donnie Jenkins and frankly their advice to you is probably pretty general based on their experience with all kinds of bikes, not the FJ specifically.
Are you really being serious to tell me they have spent any time with 30 year old FJ specific motorcycle testing?
Did they invest in an FJ and design a shock specifically for the FJ?
Did they ask Penske, Hagon, Ohlin or Fox to design a FJ specific shock?
Do any of the above manufactures offer any patented technology?
Pat, you are right, those guys who work on all kinds of shocks on all kinds on different motorcycles are specialists in their area and according to their advice to change the shock linkage you have found that be be the gospel.
But they are still working with a universal product that is adapted to fit your FJ as well as a bunch of other applications.
Since we are calling out shock people, after working tirelessly with Don Richardson and Brian Salter of Ricor on the development of the Yamaha FJ specific RPM rear shock, I feel they are spot on with their advice of not altering the shock linkage geometry. Hell, Don is the one who designed and patented the IAT system that no one, I mean no one can use without paying the rights for it.
Does Penske use it?
How about Hagon, Ohlin, Fox or any other shock manufacture...nope.
Does any other shock actually offer a truly tuned shim stack rear shock for the FJ...Nope.
They can't build the true, proper shim stack for the FJ; they have to rely on a weak shim stack and "adjustable" orifices to tune in your shock for your specific motorcycle. Why, because no one would buy a true shim stack shock because it would right like shit on the road; much too stiff. That is why you have to have your remote reservoir and adjustments on the shaft, to compensate.
No matter how you slice it, every other shock on the market is a universal product for a wide range of motorcycles and it also happens to fit your FJ.
During the design of the RPM shock, did we try altering the shock linkage geometry; yes, did it work...nope.
Will there ever be an adjustable RPM FJ specific shock...nope.
And finally Pat, is 3/4" a big deal, yes it is. Depending on which linkage system you are looking at it is a pretty severe change of the relay arm and that does several affect the valving of the shock. The distance from the relay arm mounting/pivot point and the shock mounting pivot, compounds the leverage required the farther it gets away from the factory designed center line. Does your shock offer a way to compensate for that, yes it does with all of the "adjustments" you can make.
I will hold fast on my learning experiences of designing and applying the best and patented shock technology to the FJ. Maybe when Ed Sorbo or Donnie Jenkins patents some new technology, spend the time & money designing it specifically for the FJ then I might take their advice. But for now, I will stick with the ones who worked with me, investing their time and money with me for a FJ specific shock application, not a universal product that just fits and you can adjust.
Am I suspension expert?
Maybe not an expert, but I do have a lot of shock tuning experience from my race car days I fully understand how it all works and I am definitely not a garage hobbyist relying on the advice of others. My experience assisted in the design of the RPM shock with Don & Brian as I was actually able to give them proper feedback in designing and ultimately producing the only aftermarket shock for the Yamaha FJ1100 or FJ1200.
Sorry, no universal application shock available from RPM; you have to call Penske, Hagon, Ohlin or fox for that.
Self-serving...you better bet your ass.
Randy - RPM
Now, I am going to go to lunch and then start back to work on your FJ when I get back.
So randy do you have a used rpm shock in great condition in the $500/600 range?
Quote from: yambutt on February 03, 2016, 02:57:46 PM
So randy do you have a used rpm shock in great condition in the $500/600 range?
Sorry, no used ones that I am aware of.
Randy - RPM
Randy what is the length of the 1992 original rear shock, slso I will be ordering your fork valves and springs next month....thanks
I will concede that that the IAT valving technology is a more modern design***than the tried and true shim stack technology. I will concede that for a stock FJ, using the stock tire sizes, the RPM shock is fine.
**The IAT valving will become last week's news when the new generation ESA shocks will hit the market.
So, getting back to the subject of rear height adjustment, on the '89-93 FJ's Ricor thinks it's fine to alter the dog bones?
It's just that the early FJ's are SOL?
Rim conversions vs Ricor recommendations:
How about the early FJ folks who want to do the 17" rim conversion and have the ability to use modern (read superior) 17" tires in the 180/55 size?
What does Ricor recommend for FJ suspension adjustment to compensate for the smaller diameter tire?
Don't do the conversion? It's not needed?
Modern tire technology has no place on a 30 year old bike?
Lower the front forks?
Where we fundamentally differ is the understanding of adjustability.
You keep saying that the Penske/Hagon/Ohlin shocks are inferior because they can be set up for many different applications. I disagree.....Adjustability is good. The more the better.
I believe the more adjustability a product offers, the wider the application the product can fit.
**It is a tactical error for Ricor to make a $900 shock for our FJ's with no provisions for height adjustment**
Period.
Like I said, IAT valving technology is cool, but the writing is on the wall, it will be superseded by the ESA shocks with push button adjustability (there's that word again: adjustability) when they become available for our bikes.
Want to bet that those ESA shocks will also be height adjustable?
There's that word again.....
Some time back the lengths of all three shocks were posted. Have you tried the search function? Many find Google searches easier when they include "FJowners" in the search line (remove the quotes).
Think I found it on here, thanks, looks like its 300mm
shock length site:fjowners.com
Ed, gonna post up pics of our defiance of El Nino ride? A tad cold but really good weather and riding....
Quote from: FJmonkey on February 03, 2016, 07:43:12 PM
Ed, gonna post up pics of our defiance of El Nino ride? A tad cold but really good weather and riding....
(popcorn)
Nice redirect Pat...
ESA shock for a FJ :rofl::wacko2: :wacko1: :rofl:
Lets get back to the topic at hand and not worry about the future. I seem to recall a movie made 30 years ago that predicted we would all have flying cars by now, hell even the "hover board" still has wheels...I will answer the questions I posed to you, plus answer your questions below.
Are you really being serious to tell me they have spent any time with 30 year old FJ specific motorcycle testing?
I'll let you answer this oneDid they invest in an FJ and design a shock specifically for the FJ?
NOPEDid they ask Penske, Hagon, Ohlin or Fox to design a FJ specific shock?
NOPEDo any of the above manufactures offer any patented technology?
NOPEDoes Penske use it? (IAT technology)
NOPEQuote from: Pat Conlon on February 03, 2016, 05:16:53 PM
I will concede that that the IAT valving technology is a more modern design(*)than the tried and true shim stack technology.
(*)The IAT valving will become last week's news when the new generation ESA shocks will hit the market.
Do you really think your shock is a "true shim stack shock"? What do you think you are adjusting when you adjust all of those adjustments on your shock? I'll tell you, needle valves in orifice to control oil flow, not the shim stack. (just like your idle mixture screws)Quote from: Pat Conlon on February 03, 2016, 05:16:53 PM
I will concede that for a stock FJ, using the stock tire sizes, the RPM shock is fine.
How can you concede to something you have no idea what you are talking about, when was the last time you rode a stock FJ with RPM suspension components? Maybe that is the reason for the re-direct to ESAQuote from: Pat Conlon on February 03, 2016, 05:16:53 PM
So, getting back to the subject of rear height adjustment, on the '89-93 FJ's Ricor thinks it's fine to alter the dog bones?
Yes, the rear height adjustment is much better completed after the relay linkage. Just like installing a drop spindle to lower a car or a block to raise or lower the ride height of a leaf spring vehicle; in both of these examples, the ride height is altered but the suspension geometry is not.
If the relay arm geometry is changed there are leverage issues that come into play that alter the shock valving throughout the stroke. There is a thing called moment of center (similar to TDC & BDC in an engine) and 99% of all shock relay linkages are design to operate on the moment of center. That way no matter what, the up or down movement of the relay arm is on a constant arc, but the shock pivot point gets closer to the pivot above & below the moment of center. This moment of center affects all kinds of things on bikes & cars. Your chain tension with the swing arm down compared to perpendicular to the front sprocket is the best example I think everyone can understand. If the chain is adjusted too tight at rest, when you sit on the bike and the swing arm come closer to level, the chain gets tighter.
On a car the moment of center applies to both front & rear suspension that affect caster & camber changes through the suspension travel, rear steer in the rear suspension. Shock performance due to angle changes through the suspension travel.
So here is a little theory on changing the relay arm linkage, lets move the relay are down 3/4" with your shock and the relay arm is now at the 7 o'clock position compared to the original 9 o'clock. The leverage it take to come back to the moment of center (9 o'clock in this example) in compression is greater. That is because the leverage of the shock, since it is now not at the moment of center is closer to the actual pivot pivot point. So, you have now increased the leverage required to move the shock, which requires the valving in the shock to be lighter because of the additional require force to move the relay arm to moment of center. Then the linkage arm gets to center and goes over and the shock valving is too soft.
So, with the Yamaha design, the relay arm is at or near the moment of center (depending on rider weight) and the RPM shock valving can be even and consistent. There is no compromise required in valving to make the shock work properly.
Now, with your longer Penske shock, you have to adjust the compression of the shock to compensation for the moment of center dependency due to the light shim stack, but hey, you have an adjustable shock.Quote from: Pat Conlon on February 03, 2016, 05:16:53 PMIt's just that the early FJ's are SOL?
In Ricors eyes, raising the rear of the bike is not their issue. They designed a specific shock with all of the linkage geometry in mind, not the end users modified ride height requirements. I started looking at designing a rear portion of the early linkage to raise the rear of the bike, but I looked at investment Vs. return and I am not sure I can ever recover the invest made to change the system. (maybe someday I will manufacture a solution)Quote from: Pat Conlon on February 03, 2016, 05:16:53 PMRim conversions vs Ricor recommendations:
How about the early FJ folks who want to do the 17" rim conversion and have the ability to use modern (read superior) 17" tires in the 180/55 size?
My 86 is running a pilot power 3 in the aforementioned size and I did not notice a difference in the ride height while riding, in fact when I changed over to the RPM shock, the bike was some much quicker due to the back tire actually stay connected to the pavement. Even Monkey Mark says the same thing, he does not feel he is riding any "faster" but his lean angles have increased as well as his speed due to the improved performance of the RPM suspension components.Quote from: FJmonkey on May 01, 2015, 02:37:56 PM
I cannot vouch for them as I went from a sacked out old OEM shock to the RPM shock. The difference between them is Night and Day. My last ride was a pleasant surprise to me. I found my Chicken Strips reduced by half, I did not feel that I was riding any harder or faster than my normal rate. Having a better shock than OEM allowed this new comfort zone to happen with no intentional input from me.
Quote from: Pat Conlon on February 03, 2016, 05:16:53 PMWhat does Ricor recommend for FJ suspension adjustment to compensate for the smaller diameter tire?
Again, not their problem, they are a shock manufacture, not a suspension design & manufacturing company (Again, maybe someday I will manufacture a solution)Quote from: Pat Conlon on February 03, 2016, 05:16:53 PMDon't do the conversion?
They don't care what you do with your wheels, that is not their field of operation; they manufacture shocks.Quote from: Pat Conlon on February 03, 2016, 05:16:53 PMIt's not needed?
Once again, my 86 rides on stock suspension components and I have not had any personal issues. I have also not heard from a single early RPM shock purchaser regarding ride height issues.Quote from: Pat Conlon on February 03, 2016, 05:16:53 PMModern tire technology has no place on a 30 year old bike?
Not sure what you mean there, sure we all want the latest & greatest.Quote from: Pat Conlon on February 03, 2016, 05:16:53 PMLower the front forks?
Why would you need to do that, because the rear of the bike went down by 1/4"?Quote from: Pat Conlon on February 03, 2016, 05:16:53 PMWhere we fundamentally differ is the understanding of adjustability.
You are right there, I am speaking from knowledge, experience, education & on the job training with both race car and motorcycle suspension systems. So far you have offered the advice of "experts" for which you have received.Quote from: Pat Conlon on February 03, 2016, 05:16:53 PMYou keep saying that the Penske/Hagon/Ohlin shocks are inferior because they can be set up for many different applications. I disagree.....Adjustability is good. The more the better.
I never said any of those shock are "inferior", I am telling you there a universal product that can be bolted onto a variety of motorcycles and they have to provide the adjust-ability to be able to cover all of the differing applications, you seem to think those are there to give you a better product.Here is question for you, how many hours did it take for you to get your Penske and the USD's dialed in?Quote from: Pat Conlon on February 03, 2016, 05:16:53 PMI believe the more adjustability a product offers, the wider the application the product can fit.
**It is a tactical error for Ricor to make a $900 shock for our FJ's with no provisions for height adjustment**
Period.
That is your opinion and that is all that it is. Yes, with all of the adjust-ability you can bolt the shock to a bunch of different bikes and it will work. As far as I know you have never ridden an FJ with a RPM shock, early or late design or fork valves, maybe I am wrong. But, I have no doubt based on the directions of this topic each & every time, your preconceptions would never offer any of the RPM suspension components a fair assessment. Quote from: Pat Conlon on February 03, 2016, 05:16:53 PMLike I said, IAT valving technology is cool, but the writing is on the wall, it will be superseded by the ESA shocks with push button adjustability (there's that word again: adjustability) when they become available for our bikes.
Want to bet that those ESA shocks will also be height adjustable?
There's that word again.....
You have got to be kidding again right, who is their right mind would invest the cubic dollars into the application of a ESA (Electronic Suspension Adjustment) shock on a FJ? Hell, where would you place the stepper motor, and then you have to have an ECU and key pad; you had to modify your side panel to make your current shock work now...
(http://i1215.photobucket.com/albums/cc517/racerrad8/002_zpsojnmpnle.jpg~original) (http://s1215.photobucket.com/user/racerrad8/media/002_zpsojnmpnle.jpg.html)
I am sure you nor anyone else for that matter is aware, but once I sell this final batch of the RPM shocks I have received this past month I am finally able to completely recoup the investment I had to make to design & produce the RPM shock; It has taken three years to do that. Ricor told me I was crazy investing into a 30 year old motorcycle when I first talked with them, but they gave me a price, I evaluated and determined I could make it a go; and I did. Hell, Hindle said the same thing when I started the header system a few years back for the FJ and I am still working on recouping that investment.Pat, I question for you: Do you know why the raising of the rear ride height makes the bike handle "better"? There are two main reasons why this affects the handling, do you know what they are?
Pat it is time for you to bring some tech to this topic and please leave the "expert advice" & the future out of it.
I received this email today from yambutt who is working with HyperPro for his rear shock needs.
Name: yambutt
Email: XXXXXXXXXXX@yahoo.com
Message: Randy, would've loved to get a used RPM shock but anyways have to go with hyperpro, so they need to know the length of the original rear shock on my 1992 fj, gonna stay with the factory length and raise it with the dog bones....thanks.By the way Klaus Huenecke with hyperpro agreed with keeping the rear shock the length Yamaha intended it to beWith that, I guess we are in a dead tie on this topic...Ed and Donnie say longer shocks are the ticket and Randy & Klaus say, the factory designed geometry should be maintained...
I will close my post out with a statement I have both heard personally and has been written on the forum by our own Mark O who is a Penske shock and RaceTech fork valve owner. I know he posted it a while back, but it still hold true as demonstrated at the 2015 Renegade rally where the stock wheeled, RPM outfitted FJ lead the pack and there was only one who could keep up and he was riding an aprillia.
Quote from: Mark Olson on June 08, 2013, 01:55:24 PM
Alright boys, here is the dealio .
I had the opportunity to follow Mike Ramos at the WCR on the hwy 20 rip and grip . He was able to hang with the Nor cal Renegades . Known at the Wcr as the "fast five".
I purposely followed Mike R. so I could see his bike in action with the RPM front and rear set up in action. It performed flawlessly , no unsettled wiggle or big ass bouncy wiggyness . We were flying and even with the last second quick downshifts to 2nd gear and throttle up reducing corner surprises the suspension took it.
So, to sum it up the RPM stuff works as advertised.
I believe adjustable dog bones would be better than an adjustable length shock. The raising of the rear is necessary just to bring back to stock when you put a low profile 17" wheel on the rear. Those of you who want a better turn in ratio can raise it a little more for your liking.
Monkey Mark has a plan to use the shock linkage from a 89-90 on the earlier 84-87 fj's and says it matches so you can use the later model shock.
I have the race-tech springs and emulators on the front and the penske 3-way adjustable rear on My 86 . I have spent a bazillion hours and thousands of miles getting my fj just the way I like it.
With RPM Randy offering a one size fits all Rear shock I am thrilled . I will be doing a straight up comparison to how it works right out of the box as opposed to literally years of dicking around with the penske. Look for the Muppet Labs report when I am finished.
MarkO
Randy - RPM
BTW, I got your pistons cut this afternoon, everything is assembled for the final pour in the morning. If all good, final assembly tomorrow.
(http://i1215.photobucket.com/albums/cc517/racerrad8/Pats%20Pistons%201_zpsqamnngc4.jpg~original) (http://s1215.photobucket.com/user/racerrad8/media/Pats%20Pistons%201_zpsqamnngc4.jpg.html)
(http://i1215.photobucket.com/albums/cc517/racerrad8/Pats%20pistons%202_zpsfrofbtva.jpg~original) (http://s1215.photobucket.com/user/racerrad8/media/Pats%20pistons%202_zpsfrofbtva.jpg.html)
Yea, it's coming... Like a fine whine, no pix before their time ...
Quote from: racerrad8 on February 03, 2016, 11:05:43 PM
BTW, I got your pistons cut this afternoon.......
Subtle! :rofl:
Noel
oooooh, I wake up and what do i find...
I concede: meaning I will accept as true many other FJ owners anecdotal evidence on the performance of the RPM shock.
I love quizzes: By increasing the height of the rear end you change the handling of the bike by reducing the rake of the front forks and by increasing the angle of the swing arm, you slightly shorten the wheelbase.
So what I've learned is this:
1) The RPM IAT shock made by Ricor is custom tuned for our FJ's and the tune is so fine that a 3/4" adjustment on the shock shaft will negatively affect the tune.
2) If the owner wants to change the geometry of the linkage by installing shorter dog bones, the IAT shock will be fine with the change.
3) If you don't have a suspension with dog bones, there will be no future provisions for length adjustment in the RPM shock.
4) Manufacturers, vendors and suspension folks who make, sell and tune height adjustable shocks advise that (slightly) lengthening the shock is advisable vs changing the swingarm linkage.
This is different than saying: There is no reason or benefit in raising the back end on our FJ's.
Heh heh, where else, but on our FJ forum can you lather up the best FJ vendor in the world while he is right smack dab in the middle of building your engine?
At this point in time is this really a good idea?
I thought about it before I replied, but what the hell, Randy is also a friend. I seem to recall that I introduced Randy to Don Richardson of Ricor. Don is the guy that came up with the tuned damper used in the Vibranators.
Discussion is good. Different view points are good. It's all good.
So I enjoy the quicker steering. From raising the rear of the bike. (And slightly lowering the front) Monkey Mark when are you going to make the upper shock bracket. So the early owners can adjust the rear ride height via dog bones and use the RPM shock. Randy someday I will put your exhaust on the 1350. Awesome exhaust. Unbelievably light. Are those pistons. Cut for the better oil rings for the 1350? Or is it something else?
I decided to change direction. Those are the 83mm long skirt Ross pistons. Randy's cutting them down to get the compression down to ~10:1
The report I had on new oil ring design for the Hank Scott Pro Lite pistons was that it did reduce oil consumption, but was still using oil, 1 quart every 3k miles.
Ross won't make them with lower compression? I thought they would make pistons to your spec's. And why are you going to long skirts?
Quote from: Pat Conlon on February 04, 2016, 09:44:25 AM
Heh heh, where else, but on our FJ forum can you lather up the best ...
Discussion is good. Different view points are good. It's all good.
(http://fjowners.com/gallery/9/630_04_02_16_10_54_42.png)
Quote from: giantkiller on February 04, 2016, 11:00:20 AM
Ross won't make them with lower compression? I thought they would make pistons to your spec's. And why are you going to long skirts?
Ross will custom make pistons to any specifications. These are off the shelf from Curt Andrews with an advertised compression of 12:1
http://andrewsmotorsports.mybigcommerce.com/yamaha-fj-fj1100-fj1200-xjr1300-1380cc-ross-piston-yamaha-cylinder-kit-83mm/ (http://andrewsmotorsports.mybigcommerce.com/yamaha-fj-fj1100-fj1200-xjr1300-1380cc-ross-piston-yamaha-cylinder-kit-83mm/)
12:1 compression may be fine for racers but not for an aircooled/carburetted street bike, in the toasty desert where we get piss water Calif 91 octane E10 fuel.
10:1-10.5:1 is much safer, power output will be reduced, but so be it.
I want an engine that is oil tight. I ride my bike on 3-5k mile tours, typically 300 to 600 miles a day.. Regardless of the wonderful power output of the 82mm Pro Lite pistons, I dislike having to carry and frequently add oil on these tours.
A fresh engine with the new design oil ring in the Pro Lite pistons that still uses 1 quart in 3k miles is not what I want.
Quote from: giantkiller on February 04, 2016, 09:49:10 AM
Monkey Mark when are you going to make the upper shock bracket. So the early owners can adjust the rear ride height via dog bones and use the RPM shock.
I have the design roughed out for the upper shock mount. I planned on finishing the hole location when I had the time and funds to start the '86 rebuild, I wanted the upper mount hole located to keep the stock rear height with the RPM '89/'90 shock and OEM dog bones. Then fine tune with custom dog bones for my 17" rear set up. I can ask a few vendors for the cost of a short run of 10 pieces or so, it won't be cheep. Here is what I have modeled so far. The upper hole is just a guess, if I made some up I would remove the hole and add it after mocking it up on the rolling chassis.
(http://fjowners.com/gallery/8/104_01_02_15_5_39_17.jpeg)
I would for sure take 2. I'm going to use them to put the r1 swingarms(braced and 2 1/2 " longer) on the 1350 and the Turbo bike. I will need the upper mount as high as possible. So no hole would be great. As soon as you get it going let me know. If you need me to buy a third I will. If you don't get enough interest from others.
Thanks Mark
Quote from: giantkiller on February 04, 2016, 11:00:20 AM
Ross won't make them with lower compression? I thought they would make pistons to your spec's. And why are you going to long skirts?
Because anything above the knee is considered provocative? :rofl:
Good discussion gentlemen!
If I may add my experience with the RPM shock......
I have at least one hundred thousand miles on the RPM shock over the past several years. I would like to address a different aspect of adjustments as they pertains to the real world....
Although Mr. Conlon's comments are no doubt altruistic in nature, the logic as it pertains to the street riding is questionable. It is a fact that a multitude of adjustments are beneficial within the confines and the known variables of an individual race track.
However, when away from the controlled environment of a race track, all the numerous adjustments are of limited use when encountering the UNKNOWN variables commonly encountered while riding on the road. The road conditions are constantly in flux and often unexpected; at times they are dangerous. If the veracity of such a broad statement is in question, please review any of the several videos that have been posted which validate the ability of the RPM suspension to adapt to these variables instantly and effortlessly.
The importance of the suspension (both the forks and shock) being able to adapt instantly, without rider input, is of the utmost importance. When the front and rear are adjusted properly, the all around ride is excellent; both over-the- highway cruising AND back road sport riding situations are addressed with competence; it is an experience in which the rider enjoys the best of both worlds.
There is also the advantage of the extended mileage of the RPM shock between servicing which is perhaps twice as long as most other units.
Concerning the height adjustments to the rear: As a general rule, raising the rear compromises high speed stability and maneuvers. In addition, the increased fork angle under hard braking makes for a too-quick steering situation, complicating the moment when the brakes are at maximum and then gradually released throughout the turn.
Unless the issue of counter steering is addressed, discussions of the claimed advantage of raising the rear height are not complete. On the street, the advantage of counter steering will often negate the perceived advantage of raising the rear to an exaggerated height. Practicing proper counter steering techniques will enhance the rider's ability to "flick" the motorcycle from side to side rapidly in a smooth & controlled fashion. This is one aspect of motorcycle riding that is not often addressed yet one that is important and, just as with braking drills, should be conscientiously practiced.
Ride safe everyone.
Mike I have followed you through the mountains at the East coast. You are an excellent rider and smooth transitions, good lines. I have great respect for you. Your ability to cover unbelievable distances. Is impossible for me to wrap my head around.. I guess I forget that some riders don't know about counter steering. That's kinda hard to understand too.
Quote from: giantkiller on February 06, 2016, 07:33:47 AM
Mike I have followed you through the mountains at the East coast. You are an excellent rider and smooth transitions, good lines. I have great respect for you. Your ability to cover unbelievable distances. Is impossible for me to wrap my head around.. I guess I forget that some riders don't know about counter steering. That's kinda hard to understand too.
You ought to check out a couple of the counter steering threads over at ADVRider.com if you want to be truly amazed.
Nice read. All I can add is that I have played a lot with adjusting the rear end height. Probably have 6 or 7 sets of dogs bones out on the shelf. As Mike covered
"Concerning the height adjustments to the rear: As a general rule, raising the rear compromises high speed stability and maneuvers. In addition, the increased fork angle under hard braking makes for a too-quick steering situation, complicating the moment when the brakes are at maximum and then gradually released throughout the turn."
At my highest setting I was on the freeway with no particular problem other than being slightly more sensitive, then on a off ramp doing some firm braking the front end went into a BAD shimmy, got off the brakes and it stabilized, back on to stop and again shaking. Got my attention........ Since then I have concluded that staying close to the stock height is a better place for me. At present I am around 5/8 inch higher than stock. The front and rear seem to be in good balance now. Just relaying my experience in reference to raising the rear end height.
George
Quote from: racerrad8 on February 03, 2016, 11:05:43 PM
Randy to Pat - "As far as I know you have never ridden an FJ with a RPM shock, early or late design or fork valves, maybe I am wrong. But, I have no doubt based on the directions of this topic each & every time, your preconceptions would never offer any of the RPM suspension components a fair assessment..."
I'd like to weigh in on this after having RPM suspension on my '84 for a few weeks now...
I had the fork valves and the rear shock installed by RPM. It wasn't plug and play exactly in that some preload tuning was required, but it was pretty darned close. I made my final 1/4 turn adjustment on rear preload yesterday and just rode for ~2 hours on the local goat trails (Ramos and Rick will remember some of them). The bike is transformed... turns in easier and is MUCH more planted, even heavy breaking on turn in with broken pavement is totally solid. I could get around pretty quickly on the '84 with what turned out to be pretty f'd up stock suspension and the A/D didn't bother me except for the annoying 2-step front brake engagement as the A/D piston moved before the brakes went to full power. I'm completely sold on this being a huge improvement based on cornering speeds being up significantly on this common route for me... and the brakes are now predictable and 1-finger.
Comparisons to Wizard are difficult... With Diane and me on the bike, it is similar to the RPM setup on the '84 I think. For me solo it is a bit harsh feeling. You could likely get it to ride similar to the '84, but it would take some work and involve changes to more than preload on both ends. I still love Wiz for sure, but it is mostly my 2-up ride now.
If you're looking for the quick path to making your stock FJ into a modern feeling bike, at least from quality of ride POV, you'd be a fool to get into the heavily adjustable end of the pool when Randy has solved the puzzle for you.
Frank