2013-'15 A - Broken fork Compression Valve

[raYzerman]

Call this a combination of a cautionary tale, technical talk and public service announcement all-in-one...........

In follow-up to my post in What Did You Do To Your FJR Today on Dec. 13/24........ quote "........ There's a wee design issue with the 2013-15A models in that several have broken the compression valve at the bottom of the cartridge on the right hand fork. It's weak, and been discussed a few times on FJROwners. Yamaha does not sell cartridges or complete forks for these bikes. Design was changed in 2016, but those cartridges don't or suspected to not fit.. the whole fork has different part numbers. We'll see.

Anyway, I was taking care not to use impact gun, it all came apart normally, no issues at all. As I (lightly) was installing the bottom bolt in the cartridge, the freakin' compression valve broke. There are options but all will take over a month to resolve...... bike is parked inside my shop door with no forks and no way to move it.

Seals were replaced by a local dealer 20k kms. ago. Did not replace the totally worn out lower bushings, I suspect they did not even have the forks apart and did it hydraulically. I hate dealers. The broken part of the valve had evidence of a pre-existing crack... could have been broken by Yamaha (KYB) during initial assembly... again, weak design, torque spec too high. We'll never prove it either way.

So, looking for (a) a cartridge 2013-15A in any condition (can use lower section of the cartridge), (b) complete right fork in any condition, (c) complete set of Gen2 forks in good condition, (d) a set of Andreani cartridges (U$600). AFAIK, no one (e.g. RaceTech) makes replacement valving, but we still need to pursue with others (Cogent says they don't). RaceTech lists a kit, but the photos are all wrong, should call them to clarify. Just going to keep calm and work through the options.... "

You can follow a more detailed story on FJROwners
https://www.fjrowners.com/threads/canno ... st-1397989

Shortly after that post, and after contact with my local suspension shop (a RaceTech dealer), we decided it was more expedient and cost efficient to buy the Gold Valve kit made specifically for Gen3 FJR's with single sided damping on the right hand fork.... well, it arrived yesterday and when I opened the box, found only gold valves and shim stacks, and no replacement compression valve body (as we had in the past with Gen2 kits). Looking again today, it looks like they may have dropped that from Gen2 kits as well..... RaceTech did not respond to my earlier emails, nor could I reach them by phone.... I have another inquiry into my local suspension shop, who are suspension experts, but not really experienced in FJR-speak.

First pic is what we got some years ago with the Gen2 kit...... second pic is the Gen3 Gold Valve kit....

[raYzerman]

This is the real problem.... on the left is the dummy left side cartridge, no valving on that side. On the right is the right cartridge compression valve, disassembled. Note broken piece through the middle of the machined groove, where a 3mm dia. hole exists for oil flow. From my further reading, this hole is a stress riser combined of course with the thin material in that area.

How does it get broken? We had evidence of a pre-existing crack, perhaps due to previous fork seal service on these forks by a dealer. When I was putting the cartridge back in and started to tighten the lower fork bolt, it broke unexpectedly easily. What is important is to ensure the cartridge is fully seated into the lower fork tube at the bottom so there is no gap between them..... then, while using a cartridge holding tool, you can install the bolt and minimize any potential damage. This is the public service announcement... be f-ing careful and know what you are doing. Dealers have broken them for people, so... I'd rather do it myself, the only guy I can trust to do it right, and even then.... look what happened. I'm pissed.

So here it is a month later and we don't have a fix. Good thing it's winter..........




For 2013-2015A FJR's, replacement parts, cartridges or even complete fork assemblies are unobtanium, Yamaha does not sell them. You are forced to aftermarket solutions such as Traxxion, Andreani or GP Suspension replacement cartridges... Andreani being the cheapest at ~U$600, the others over double that.

Additional solutions are finding a set of Gen2 forks, buying a complete 2016-up A model fork assembly ($$), or perhaps welding up and machining the broken valve (all welding shops here are busy and not interested, but I'm not giving up yet). I have located used Gen2 fork set for ~U$500-ish.

[FJRoss]

This is the real problem.... on the left is the dummy left side cartridge, no valving on that side. On the right is the right cartridge compression valve, disassembled. Note broken piece through the middle of the machined groove, where a 3mm dia. hole exists for oil flow. From my further reading, this hole is a stress riser combined of course with the thin material in that area.

How does it get broken? We had evidence of a pre-existing crack, perhaps due to previous fork seal service on these forks by a dealer. When I was putting the cartridge back in and started to tighten the lower fork bolt, it broke unexpectedly easily. What is important is to ensure the cartridge is fully seated into the lower fork tube at the bottom so there is no gap between them..... then, while using a cartridge holding tool, you can install the bolt and minimize any potential damage. This is the public service announcement... be f-ing careful and know what you are doing. Dealers have broken them for people, so... I'd rather do it myself, the only guy I can trust to do it right, and even then.... look what happened. I'm pissed.

So here it is a month later and we don't have a fix. Good thing it's winter..........


For 2013-2015A FJR's, replacement parts, cartridges or even complete fork assemblies are unobtanium, Yamaha does not sell them. You are forced to aftermarket solutions such as Traxxion, Andreani or GP Suspension replacement cartridges... Andreani being the cheapest at ~U$600, the others over double that.

Additional solutions are finding a set of Gen2 forks, buying a complete 2016-up A model fork assembly ($$), or perhaps welding up and machining the broken valve (all welding shops here are busy and not interested, but I'm not giving up yet). I have located used Gen2 fork set for ~U$500-ish.

Wonder if you could drill and tap both sides and use a short piece of threaded rod and red Loctite to rejoin? Obviously, it would have to be dressed to spec on a lathe afterward. Is that just a simple hole drilled through the recessed part?

Edit: I see from the diagram in later posts why this wouldn't work. Didn't realize that the body was hollow.

[SkooterG]

That sucks!

I am disappointed in RaceTech's lack of response. Years ago I always had good dealings with them.

I am fairly certain this happened to the fork on my high mile '13 FJR. When I found a local guy to service them and add the Traxxion springs (found on google. Mainly dirt bike stuff out of his garage) the damping worked like shit afterwards. I didn't know about this issue yet but knew he fucked something up. I ended up buying a complete right side fork from Great Britain off ebay. Not too bad iirc - maybe $200? Found another local suspension guy to combine the two for a good right side fork. The whole experience has motivated me to learn how to do it myself next time. But now I see even I have a good chance of screwing it up. Fortunately, most of my FJRs are either ES or aftermarket suspension. Actually, if all goes well, I will get rid of enough of them over the next few months to no longer have any 13-15 'A' model forks.

[bigjohnsd]

Ray, seems to me like a local job shop could recreate that piece for way less than $600?
https://www.miltonmachineshop.ca/services/

[gixxerjasen]

[BkerChuck]

Ray, seems to me like a local job shop could recreate that piece for way less than $600?
https://www.miltonmachineshop.ca/services/

I'll get our shop machinist lead to take a look at this tomorrow and get his opinion. Biggest problem is in machining a single piece. Most of the expense is in set up time. Our machine shop rate is $150/hour currently.

[bigjohnsd]

Ray, seems to me like a local job shop could recreate that piece for way less than $600?
https://www.miltonmachineshop.ca/services/

I'll get our shop machinist lead to take a look at this tomorrow and get his opinion. Biggest problem is in machining a single piece. Most of the expense is in set up time. Our machine shop rate is $150/hour currently.

Ray could become a vendor, LOL

[Boston]

soooo $150.00 + part.

[BkerChuck]

Machinist lead says it's definitely something we can do here but until he has one in his hands it's hard to put a real number on it. He'd need to know exactly what the material is, precise sizes, threads, etc but does feel he could program our Haas to make them. Biggest issue obviously is going to be the programming and set up for the first one. He's open to a side hustle but wants to know how many pieces are we looking at. Anybody have a good one laying around they can send our way? I don't really want to tear my bike apart right now to take mine out.

A few other questions for the brain trust he's asked. The 3 mm cross hole for oil flow, he's thinking that might be part of the problem. We have the retention bolt coming up from the bottom and not too high above that is the cross drilled hole. Could that hole be moved a little higher away from the retention bolt? Can the hole size be decreased to lessen the chance of breakage? Instead of one large hole could 2 smaller holes be drilled? Can the depth of the hole for the retention bolt be shortened and a shorter bolt installed to create some more space and reduce the chance of breakage?

[raYzerman]

Absolutely appreciate everyone's input...... Understand I'm just the guy in the middle and the owner has to decide what to do. Well he made a suggestion I hadn't thought of, two heads are better than one..... so I studied the part some more and measured up, made a preliminary CAD drawing. The compression valve body design is an intricate complicated thing, and to duplicate the part would be guessing a bit on the oil flow and dimensions.... and be terribly expensive. The material is some high grade aluminum alloy, but one would still end up with a weak point that could still break. I have a couple of lines on used Gen2 forks, looking at U$500. However.......

Here's what we come up with... keep the main body of the valve to preserve the original design. Machine the broken lower extension piece off and flush to the main valve body. Lots of meat available to counterbore and thread a STEEL insert (5/8" OD). Counterbore to 8.8mm to match the internal bore, which coincidentally is the drill size for the lower bolt (M10 x 1.25). Machine the groove and drill the 3.0mm hole for compression oil flow. The part extends exactly 18mm below the main body..... preliminary drawing, I gotta work some more on this..... must add metric equivalents and notes.

Owner has a number of precision machine shops in his area an hour north... Mennonite country, or the machine shop John mentioned. Will take all the goodies to one of them and 'splain more. Seems simple. How many do I make? If somebody broke theirs, all they'd have to do is clean up their existing valve and counterbore 5/8" x 18 and thread 'er in. Material is 5/8" solid rod stock. The question is what grade of steel....

[Dan Cooper]

Color me curios.
What does that groove and bleed hole line up with in the lower fork outer tube?
Is it an oil flow path that lines up with the compression adjuster in the lower fork outer tube?
Is it for something else?
Does the groove need to be as deep or as square edged?

Does the dummy cartridge "compression valve" in the left fork leg look the same internally (without the actual damping valves shim stack) when removed from that cartridge body?
Could the actual valve shim stack be moved to that dummy and the groove and bleed hole machined?
I'm not a machinist, but would that "little bit" of machine work be difficult?
Those are still available from Yamaha for about $200 US.
. Cylinder Comp., 2
1MC-2315K-00-00

Someone who has already had to make this same repair by installing aftermarket cartridges might even have one of those laying around in the garage!

Expiring minds want to know!
dan

[BkerChuck]

Absolutely appreciate everyone's input...... Understand I'm just the guy in the middle and the owner has to decide what to do. Well he made a suggestion I hadn't thought of, two heads are better than one..... so I studied the part some more and measured up, made a preliminary CAD drawing. The compression valve body design is an intricate complicated thing, and to duplicate the part would be guessing a bit on the oil flow and dimensions.... and be terribly expensive. The material is some high grade aluminum alloy, but one would still end up with a weak point that could still break. I have a couple of lines on used Gen2 forks, looking at U$500. However.......

Here's what we come up with... keep the main body of the valve to preserve the original design. Machine the broken lower extension piece off and flush to the main valve body. Lots of meat available to counterbore and thread a STEEL insert (5/8" OD). Counterbore to 8.8mm to match the internal bore, which coincidentally is the drill size for the lower bolt (M10 x 1.25). Machine the groove and drill the 3.0mm hole for compression oil flow. The part extends exactly 18mm below the main body..... preliminary drawing, I gotta work some more on this..... must add metric equivalents and notes.

Owner has a number of precision machine shops in his area an hour north... Mennonite country, or the machine shop John mentioned. Will take all the goodies to one of them and 'splain more. Seems simple. How many do I make? If somebody broke theirs, all they'd have to do is clean up their existing valve and counterbore 5/8" x 18 and thread 'er in. Material is 5/8" solid rod stock. The question is what grade of steel....

Ray, our machinist lead man tells me you will then need to add a seal between the 2 pieces so the pressurized oil travels only through the designed passages and doesn't leak out at the mating surfaces. Obviously it would all be contained within the lower leg of the fork and not leak externally but it may affect the actual compression valve function.

Not trying to critique your work by any means! In fact he liked the drawing. It may not even be an issue with our application he's used to larger stuff.

[raYzerman]

Dan, the dummy valve is not usable, as it is bored right through and has no features to add damping to.... yes the groove lines up with the compression adjuster clicker thingie in the lower fork tube. That whole 18mm sits in a recess counterbore to match the 0.625. Once everything is clamped up, the oil lock piece (not shown in my drawing, and I must do so), all fluid passages are sealed.

Chuck, the idea is to drill and tap 5/8 - 18 into the existing valve and thread the insert in (0.63 deep)... it will seal without any seals... Things are going to become more apparent with the final drawing and appropriate notes added. Kinda busy, so it'll likely take me the weekend.....

[Toter]

Maybe ES versions aren't so bad after all.

[raYzerman]

You can keep your ES, lol.... For those interested in how to go about rebuilding (Gen2 in this case) forks, this video will edumacate you. Note, in the intro, he 'spains he broke his compression valve and got some from KTech... which don't sell anything for Gen3. At the 19:30-ish mark, he installs the replacements....

https://www.youtube.com/watch?v=eZAA4QS0iAA

[fontanaman]

As Toter said I am liking my ES more today than I did yesterday. It is far from perfect but it seems it is better than the 13-15A model especially considering I don't have Ray's skills. Nowhere near it in fact.

Best wishes on the fix Ray.

[Dan Cooper]

Absolutely appreciate everyone's input...... Understand I'm just the guy in the middle and the owner has to decide what to do. Well he made a suggestion I hadn't thought of, two heads are better than one..... so I studied the part some more and measured up, made a preliminary CAD drawing. The compression valve body design is an intricate complicated thing, and to duplicate the part would be guessing a bit on the oil flow and dimensions.... and be terribly expensive. The material is some high grade aluminum alloy, but one would still end up with a weak point that could still break. I have a couple of lines on used Gen2 forks, looking at U$500. However.......

Here's what we come up with... keep the main body of the valve to preserve the original design. Machine the broken lower extension piece off and flush to the main valve body. Lots of meat available to counterbore and thread a STEEL insert (5/8" OD). Counterbore to 8.8mm to match the internal bore, which coincidentally is the drill size for the lower bolt (M10 x 1.25). Machine the groove and drill the 3.0mm hole for compression oil flow. The part extends exactly 18mm below the main body..... preliminary drawing, I gotta work some more on this..... must add metric equivalents and notes.

Owner has a number of precision machine shops in his area an hour north... Mennonite country, or the machine shop John mentioned. Will take all the goodies to one of them and 'splain more. Seems simple. How many do I make? If somebody broke theirs, all they'd have to do is clean up their existing valve and counterbore 5/8" x 18 and thread 'er in. Material is 5/8" solid rod stock. The question is what grade of steel....

You asked How Many to Make?
Depending on the end price, and your success and satisfaction with the final results, I may want a few. Maybe 3 - 5.

You asked What Grade of Steel?
I'm not a mechanical engineer or a machinist but I would think the mildest, softest steel would be much stronger than the OEM aluminum.
I'm thinking even a better grade of aluminum would do the trick, but what do I know!!


If you get this thing fixed to your satisfaction will you install the Race-Tech valve kit??

dan
Expiring minds want to know!

[wheatonFJR]

If the present part is steel, use that grade of steel. If it’s made of aluminum, maybe use a different grade of aluminum. Don’t change metals…or corrosion might be in your future. Not talking to Ray, I know he knows that.

[BkerChuck]

With this piece being inside the fork and constantly bathed in fork oil I don't think corrosion will be much of an issue. My machinist coworker suggested stainless steel being an option.