Suspension SETUP, a 'how to' guide...

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Suspension SETUP, a 'how to' guide...
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flag emilemontcalm
O+
Posted: Jul 29, 2023 at 17:41 Quote
Hey guys! I found this 20% off code for gearhub.ca.
It is TR2023 and it seems to be working on everything in store.
Taught I’d leave it here if it can help out anyone!
Cheers,
flag CooperWhiteZiT
Posted: Aug 13, 2023 at 9:21 Quote
is there any why for 250x72.5 coil shock to fit on a 250x75

Thanks
flag demo7jumper
Posted: Aug 13, 2023 at 15:30 Quote
CooperWhiteZiT wrote:
is there any why for 250x72.5 coil shock to fit on a 250x75

Thanks
Offset bushings
flag averagerug
Posted: Aug 13, 2023 at 23:21 Quote
demo7jumper wrote:
CooperWhiteZiT wrote:
is there any why for 250x72.5 coil shock to fit on a 250x75

Thanks
Offset bushings

What for? Eye to eye is still the same, so static geo is exactly the same. It's only the stroke that's different, aka the amount of travel the shock has.
flag gabriel-mission9
Posted: Aug 14, 2023 at 12:11 Quote
CooperWhiteZiT wrote:
is there any why for 250x72.5 coil shock to fit on a 250x75

Thanks

There will be a 2.5mm travel limiter fitted to the shock somewhere. Have that removed and it will be 250x75. What shock is it?
flag commental
Posted: Oct 28, 2023 at 8:22 Quote
Hi guys. More of a servicing question, rather than set up.
I have a 2018 Fox DHX2 which I'm happy to service myself, although I do refer to YT videos for a bit of guidance. My shock is fitted with a low friction seal that's housed within the bearing assembly and fits around the 9mm shaft (https://www.ridefox.com/fox17/help.php?m=bike&id=868#part10707).
On one of the videos I was looking at, instead of this seal there is an o ring and split washer in it's place (https://www.youtube.com/watch?v=fBFo7dcp1YI&t=1179s @ 6 minutes 12 seconds). Can anyone tell me if these parts are interchangeable and if one method is superior to the other (parts for both methods are included in the service kit)?
Thanks.
flag gabriel-mission9
Posted: Oct 29, 2023 at 3:00 Quote
commental wrote:
Hi guys. More of a servicing question, rather than set up.
I have a 2018 Fox DHX2 which I'm happy to service myself, although I do refer to YT videos for a bit of guidance. My shock is fitted with a low friction seal that's housed within the bearing assembly and fits around the 9mm shaft (https://www.ridefox.com/fox17/help.php?m=bike&id=868#part10707).
On one of the videos I was looking at, instead of this seal there is an o ring and split washer in it's place (https://www.youtube.com/watch?v=fBFo7dcp1YI&t=1179s @ 6 minutes 12 seconds). Can anyone tell me if these parts are interchangeable and if one method is superior to the other (parts for both methods are included in the service kit)?
Thanks.

The oring and split ring is far superior, although fractionally higher friction. The friction is still far too small to be noticed on the bike, and the o-ring design is much much more durable.
Unfortunately the two are not interchangable. Whatever is in your shock currently is what needs to go back in, otherwise it wont hold pressure at all.

Saying all that, it's been a very long time since I serviced one of those and I could be wrong about the interchangability. I remember fitting the o-ring type setup to a shock that previously had the u-cup seal and that shock defo leaked as soon as I pressurised it, however that may have been an older model or something. I would 100% try with the o-ring first just to see, as the u-cup seal is incredibly fragile and best avoided if possible. I expect you will get the same leakage I did and then have to rebuild the shock using the u-cup, but its absolutely worth a try.

A word of warning about the u-cup...
Refitting the shaft with the u-cup seal in place is not trivial. If you remove the shock eyelet and try to push those threads through the u-cup, you will almost certainly damage the seal and have to buy a new kit. It's doable, but very tricky. The easier method is to remove the piston from the other end of the shaft instead and insert through the u-cup from that end. BUT... the piston is usually retained by a castellated nut on DHX2's from that era. This castellated nut will almost always destroy the threading on the shaft while you remove it. The only wat to ensure this doesn't happen consists of a bit of heat, some careful prying of the castellations and a fair sized chunk of good luck.

Basically, those are absolutely terrible shocks to service, whichever way you look at it. Good luck!

Also, without a vacuum bleed machine, it is quite tricky to get all air pockets out from behind the poppet valves.

Seriously, good luck!
flag commental
Posted: Oct 29, 2023 at 3:59 Quote
Thanks for the reply, it's really appreciated.
I've serviced the shock several times now, always removing the piston and shim stack rather than the eyelet (I bought the bike 2nd hand and had to replace the shaft the 1st time I serviced it as the coating was worn, but still removed the piston etc. as that was what was shown in the YT video). I have the bullet tool and haven't been aware of any damage to the seal on testing after reassembly. I can't remember whether the nut is castellated or not, I guess I'll find out next time it's apart.
Sounds like I've been lucky.
The shock has always worked well after servicing and I've not been aware of any issues with air (interestingly I've not seen a vacuum bleed machine used on any of the videos I've watched, both showed using a nitrile glove to bleed). I have to service it reasonably frequently, the seal on the shaft seems to fail after a time (it's on an Orbea Rallon, maybe side loading issues, also maybe why the coating was removed only on one side of the original shaft?)
I'll try the o ring and split washer next time, you never know your luck!
Interestingly I can only find the bearing assembly with the part number I gave in my previous message (all described as U cup, as are the entire eyelet assemblies), am I correct in thinking there would be a different bearing assembly available if the seal isn't interchangeable?
Thanks again for taking the time to help.
flag gabriel-mission9
Posted: Oct 29, 2023 at 12:11 Quote
commental wrote:
Thanks for the reply, it's really appreciated.
I've serviced the shock several times now, always removing the piston and shim stack rather than the eyelet (I bought the bike 2nd hand and had to replace the shaft the 1st time I serviced it as the coating was worn, but still removed the piston etc. as that was what was shown in the YT video). I have the bullet tool and haven't been aware of any damage to the seal on testing after reassembly. I can't remember whether the nut is castellated or not, I guess I'll find out next time it's apart.
Sounds like I've been lucky.
The shock has always worked well after servicing and I've not been aware of any issues with air (interestingly I've not seen a vacuum bleed machine used on any of the videos I've watched, both showed using a nitrile glove to bleed). I have to service it reasonably frequently, the seal on the shaft seems to fail after a time (it's on an Orbea Rallon, maybe side loading issues, also maybe why the coating was removed only on one side of the original shaft?)
I'll try the o ring and split washer next time, you never know your luck!
Interestingly I can only find the bearing assembly with the part number I gave in my previous message (all described as U cup, as are the entire eyelet assemblies), am I correct in thinking there would be a different bearing assembly available if the seal isn't interchangeable?
Thanks again for taking the time to help.

Occasionally I have seen a "looser" castellated nut that comes off the threads without damaging them. You may be lucky and have one of those, or you may have the updated non-castellated version Fox eventually got round to speccing. Sounds like you haven't had any trouble in the past, but if yours is the castellated type then I'd just be aware while removing it. If you notice any resistance to turning while you remove it, then stop and check the threads arent being torn up.

Wear on one side does sound like a sidloading issue. You might try (before starting the service) depressurising the shock and bolting it to the front triangle fully compressed. Then lift the swingarm to meet the shaft eyelet, and see if everything still lines up at full compression. If not, there's your smoking gun.

Its interesting Fox only list one bearing assembly. The one I tried and had fail (many years ago so my memory is hazy) I seem to remember the o-ring was not a good fit in the bearing assy. Once the o-ring was installed I could move it a couple of mm side to side (left-right, not up-down) in its housing, which suggested to me it was not making contact with the outer wall, and this is how the fluid leaked past. As I say though, it was years ago so don't take that as gospel. Perhaps I'm wrong, or perhaps Fox have discontinued an older design and now spec an updated backwards compatible bearing assembly for all model years.

If theres only a small amount of air behind the poppets, this doesn't really cause huge issues, especially once it is compressed by the back pressure from the IFP. Just something to be aware of. Its a common sticking point for any air in the system and is often reluctant to work its way out.
flag commental
Posted: Oct 29, 2023 at 13:51 Quote
Great advice, thanks again.
flag wellbastardfast
O+
Posted: Nov 5, 2023 at 8:47 Quote
Anyone know what has a smaller OD a push hypercoil or sprindex ?? Or just what the OD for a push hyoercoil is ??
flag gabriel-mission9
Posted: Nov 5, 2023 at 15:05 Quote
wellbastardfast wrote:
Anyone know what has a smaller OD a push hypercoil or sprindex ?? Or just what the OD for a push hyoercoil is ??

That is a very good question. Push shocks are essentially built around Fox geometry, so I suspect (but am not certain) that their spring ID at the narrowest point is the same as Fox.

Fox use the smallest spring ID of all shocks on the market.

Sprindex is designed to be universal, so likely fits everything (Rockshox use a larger ID than anyone else, and I believe I have seen Sprindex springs on RS shocks. Push springs certainly do not fit on RS shocks.)

I happen to have both size springs on my desk at work. I'm crazy forgetful, so reply to this message so that it shows up on my dashboard notifications in the morning, and at some point during the day I'll probably check my PB account and remember I should measure the ID of both for you.

Apologies if its a busy day and I don't check PB. I'll do it at some point in the next few days for sure.
flag gabriel-mission9
Posted: Nov 5, 2023 at 15:07 Quote
Oh, you said OD, not ID. My bad. All bets are off on that one cos Push springs flare out in the middle to god knows what size. I'll measure the ID and OD at work.
flag wellbastardfast
O+
Posted: Nov 5, 2023 at 23:21 Quote
gabriel-mission9 wrote:
Oh, you said OD, not ID. My bad. All bets are off on that one cos Push springs flare out in the middle to god knows what size. I'll measure the ID and OD at work.

Thanks mate that would help massively. Basically when you compress the shock like you say the spring flares and because it's barrel shaped it's rubbing on the inside of my shock tunnel.

So I'm looking for a spring that i can use on my push to use on it.

I'm hoping the springdex will fit because that will help with springrate and fitment fingers crossed.

 


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