I haven't found a post explicitly from anyone who has mounted an F4i shock to an '86, so I wanted to confirm something.
Dad's FJ said:
Quote
1). The top of the Honda shock needs to be drilled to the size of the FJ bolt, no biggie but keep it straight. Because the shock is narrower, two 10mm spacers need to take up the space. Image 1.
2). The bottom of the honda shock uses a 17mm ID X 24mm OD needle bearing with 2 seals. Press out the bearing and seals and replace them with two 18mm x 24mm x 12mm bearings and two 18mm x 24mm x 4mm seals. images 2-4
Does this apply to the '86 exactly? Do all ambulance models use exactly the same mounts for the rear shock?
Also, where does one find these bearings? Google and ebay are failing me when I type those dimensions in...
Quote from: fintip on March 24, 2014, 11:32:47 PM
Does this apply to the '86 exactly? Do all ambulance models use exactly the same mounts for the rear shock?
The little that I know is the 84 to 87 use the same shock mounts. They can also be converted to the 89/90 shock mount that uses dog bones for adjusting the rear back to its proper location after the 17" rear conversion. An adjustable length shock will also provide the ability to restore ride height at the rear.
Anyone have info on buying an F4i shock? I see them going from 20-100 dollars, and the price seems based mostly on how pretty it is, sometimes perhaps how late a year it is. Rarely is the mileage on it mentioned. It's really just a crapshoot no matter which I pick, right? So I should go with a cheaper one?
Does anyone know if the F4i will raise or lower the rear? Dad'sFJ said the ride height was increased; I wouldn't really want that. It's just about right for me as is. Anything to do about that? Does anyone know if that would or wouldn't or might not be the same on an '85 as on an '86?
Also, the original thread source: http://www.fjowners.com/index.php?topic=6549.15 (http://www.fjowners.com/index.php?topic=6549.15)
Quote from: fintip on March 25, 2014, 12:24:09 AM
Anyone have info on buying an F4i shock? I see them going from 20-100 dollars, and the price seems based mostly on how pretty it is, sometimes perhaps how late a year it is. Rarely is the mileage on it mentioned. It's really just a crapshoot no matter which I pick, right? So I should go with a cheaper one?
Does anyone know if the F4i will raise or lower the rear? Dad'sFJ said the ride height was increased; I wouldn't really want that. It's just about right for me as is. Anything to do about that? Does anyone know if that would or wouldn't or might not be the same on an '85 as on an '86?
Also, the original thread source: http://www.fjowners.com/index.php?topic=6549.15 (http://www.fjowners.com/index.php?topic=6549.15)
It is, of course a crap shoot buying a used shock...good luck.
The f4i will raise the rear. So much so that some folks have lengthened the side stand. For our 86 I use a small piece of 1X4 to get it back to the right level and to take some stress off the side stand. The raised rear is considered beneficial form a handling perspective. As per previous, the 84-87 are the same suspension....check out Partzilla. Some people have switched the 86 to the "dog-bone style" linkage, giving some adjustment to ride height but this will mean the F4i shock will require more modification. I think quite a bit of this info is on Fjwiki? :pardon:
About the only comment about a used rear shock is that they do wear out. Hard to find data on when to replace other than the obvious problem of leaking, bent etc.. But what I have read is that at 20,000-30,000 miles a rear shock needs to be rebuilt or replaced.
Think of it this way, every few years you change or should change your front fork oil at at 20 or 30,000 miles do you think that you might need to replace fork seals and bushings ?? How crappy was the oil in your front legs last time you changed or flushed the fluid ? Even though you "flush" the fluid I can almost guarantee that there is crap in the bottom of your fork legs at 20,000 plus miles.
That's with 2 tubes/shocks up front. Now how hard do you think the one shock is working in the back ? If we change the fork oil why do we not think about the rear shock oil ? Unfortunately the stock FJ (and other old time shocks) are not rebuildable. You can't even change there oil.
So I say if you buy a used shock consider the mileage. If it has 15,000 miles on it and you don't want to rebuild it how good is it ? IMO try to buy a rear shock with the least amount of miles on it that you can. On e bay look very closely at the used shocks posted there, I see a few with bent shafts etc.. Some are from hard abusive riding and some are bent or tweaked in accidents. A lot of wrecker and salvage yards don't look at the parts very critically. If it cleans up then it's "good'..... Surprising some don't even know what to look for, or care.
I am not against buying or using another shock, quiet the contrary I use a different shock myself. Just passing along experience and things to think about.
Some of the newer shocks are not that hard to rebuild. If you can rebuild a set of front forks then you can rebuild a rear shock that is designed to be rebuilt.
The nitrogen can be recharged by almost any shop. Not that I haven't seen people use plain air (not recommended but will work, or argon gas). A shop shouldn't charge more than 15 to 20 bucks to properly recharge a shock if you bring the shock into them. About as labor intensive as putting air in your tires with out bending over......
On your clutch cover, sand both sides, clean the cracked area up with acetone or lacquer thinner, let it dry, put some JB WELD on both sides let it dry over night and reinstall... Chances are good it will not leak until you can find a replacement cover. Did that with a BMW valve cover and it held for over 50,000 miles. Probably still on it today. The important part is sand, clean and dry.... Did I mention clean :). :morning1:
Sun is coming up and I got a shock and swing arm to install.
Cheers George
AWESOME INFO. I love this forum. You guys are the best. :good2: :yes: :yahoo:
I just went and re-read the description for the rpm rear shock. God how I wish I could afford that thing. I was daydreaming about it on my way home today.
Quote from: jscgdunn on March 25, 2014, 08:36:13 AM
The f4i will raise the rear. So much so that some folks have lengthened the side stand. For our 86 I use a small piece of 1X4 to get it back to the right level and to take some stress off the side stand...
I've found something else that works surprisingly well - a hockey puck. Easy to carry, looks cooler than a chunk of lumber,and increases the sidestand footprint on soft surfaces (like hot asphalt).
rossi
QuoteIt is, of course a crap shoot buying a used shock...good luck.
The f4i will raise the rear. So much so that some folks have lengthened the side stand. For our 86 I use a small piece of 1X4 to get it back to the right level and to take some stress off the side stand. The raised rear is considered beneficial form a handling perspective. As per previous, the 84-87 are the same suspension....check out Partzilla. Some people have switched the 86 to the "dog-bone style" linkage, giving some adjustment to ride height but this will mean the F4i shock will require more modification. I think quite a bit of this info is on Fjwiki?
It isn't on FJwiki! Yet! I have been building out an "F4i" section as I've been doing this research, but a couple days ago there was almost nothing. Like I said, I know FJdad said it raised his ride height a bit, I guess I was just kind of hoping that was really the case across the board. But I don't really want to get that deep into modifying it if I can avoid it--I'm on a budget here, that's why I'm buying the F4i in the first place.
I ask about the mounting points because I was sure that Randy originally had only 2 models for his shock mounts, and then realized there were 3, or maybe 3 and then 4, and I was just confirming that that wasn't between the '85/'86 split.
Hadn't thought about the kickstand issue. Hmmm. I don't really like that. I remember reading about your 1x4 mod. Hmmm. What to do... Don't really want to carry around a puck to use every single time, either. A minor thing, but annoying. Maybe I should look for a longer kickstand off of some other bike to transplant. Are the mounts for those pretty universal?
I had to extend the sidestand on my '91 when I mounted the F4i shock, BUT that was due to the extended length of the shock after I'd had a clevis welded to it, and had made very short dogbones to increase ride height.
On your '86, the difference in shock length is minimal, and you're not changing ride height. It is unlikely IMO that you'll have to worry about needing a longer sidestand.
BTW I do carry a 3" dia alum plate to put under the sidestand foot if I have to park on soft surfaces. (its not as heavy or ugly as a hockey puck)
My bike was short to begin with because of the 17" wheel conversion.
I don't think it's as bad as you might think.
Quote from: Dads_FJ on March 25, 2014, 09:06:27 PM
My bike was short to begin with because of the 17" wheel conversion.
I don't think it's as bad as you might think.
People keep saying this but there is very little difference in the OD between the 16" and 17". Yes, there is a difference, but hardly enough to notice. The lower profile tyre and larger rim pretty much cancel each other out.
Noel
Quote from: ribbert on March 25, 2014, 09:24:39 PM
Quote from: Dads_FJ on March 25, 2014, 09:06:27 PM
My bike was short to begin with because of the 17" wheel conversion.
I don't think it's as bad as you might think.
People keep saying this but there is very little difference in the OD between the 16" and 17". Yes, there is a difference, but hardly enough to notice. The lower profile tyre and larger rim pretty much cancel each other out.
Noel
Okay I stand corrected... My bike was short because the shock was sagged out :drinks:
Two more questions on this that I haven't seen answered. I think I read that you, Arnie, used an '06, but everyone else seems to have used something around an '02. Best I can tell, after '02, the cartridge becomes a fixed object instead of a separate canister connected via tube. (this (http://www.ebay.com/itm/Honda-F4-F4i-CBR600rr-CBR600-03-04-Rear-Shock-Cushion-/261168395860?pt=Motorcycles_Parts_Accessories&hash=item3cced97654&vxp=mtr) vs this (http://www.ebay.com/itm/X-01-02-03-CBR-F4I-CBR600-600-REAR-BACK-SHOCK-ABSORBER-SUSPENSION-OEM-/171269344257?pt=Motorcycles_Parts_Accessories&hash=item27e072cc01&vxp=mtr)).
Is there room for that canister to fit down there if it's fixed? Because I'd prefer to have a later model version, and I'd prefer to not have to come up with a mounting solution. Or does one need to buy the earlier model?
The other question is: how hard is the install? I've never needed to remove a swingarm before.
Bearings and seals ordered, just a matter of picking an F4i shock now.
The fixed canister will not work for you without removing your battery for a start.. Also give some thought to how you are going to get to the adjustments when installed in the FJ. Anything is possible, I would just stay with what works unless you want to get into a heavy mod..
George
Quote from: fintip on April 05, 2014, 06:52:54 PM
Bearings and seals ordered, just a matter of picking an F4i shock now.
Kyle,
I have a F4i shock available if you are interested. I do not know what year 600 it came from.
(http://i119.photobucket.com/albums/o145/aviationfred/IMAG0453_zps5ab4ce4b.jpg) (http://s119.photobucket.com/user/aviationfred/media/IMAG0453_zps5ab4ce4b.jpg.html)
Fred
Quote from: fintip on April 05, 2014, 06:52:54 PM
Two more questions on this that I haven't seen answered. I think I read that you, Arnie, used an '06, but everyone else seems to have used something around an '02. Best I can tell, after '02, the cartridge becomes a fixed object instead of a separate canister connected via tube.
I've fitted an '05 CBR shock to my '85 and it has the separate gas canister connected via a hose.
Kyle,
I was told (I think) that my shock was from an '04, but I don't really know.
It looked just like the one in aviationfred's photo except it was cleaner.
Since I added a clevis to the UPPER mount, I mounted the shock upside down with the hose near the swingarm linkage and have the canister mounted to the swingarm.
I think I found out that the F4i has the canister connected via hose, while the CBR600RR (nonf4i) has a solid unit. The solid unit is supposedly a higher quality shock, but not by much. (This is from info I found on skymasteres post, he put a link to a guy who dissected several shocks, included both of these.)
Put here for posterity.
Thanks for the info. Will be sending you a PM about the shock Fred, interested. Feel free to preempt me by sending me some more info about it. :hi: