help with kyb twin forks

[boydy]

G'day all

Just looking for a bit of help with a fork seal installation.

Bike is a yz250 2t 2008 model.

ok so the story so far. I managed to basically complete the actual installation of the new seals but stupidly didn't get the tool to remove the inner chamber. I have the big wrench but don't have the large hex head that goes in the middle. anyhow I just decided that I would just replace the oil from the outer tube put it all back together done deal. But then realised that the damper rod offered pretty much no resistance and would actually settle itself in a fully compressed position. A fair bit of oil did come out of the bleeder holes at some stage.

Does this mean that somehow I managed to get air in the inner chamber?
or is this because of the oil that leaked out.

I managed to make up a tool for the inside by welding a socket onto an 8 sided bolt which fits the inner cap nicely but It seems ridiculously tight is this normal?

Cheers

[Woody_393]

My showas will fully extend when compressed, it's slow, but the spring in there should let them re-extend.

I'm not sure how the KYB's work though. I'm not sure if they are the same as the Showa or not, but losing oil from that hole in the showa has absolutely no bearing on the inner chamber since it's sealed.

I'm sure someone that does know will really answer the questions, I'm just not familiar at all with the new KYB twin chambers.

[boydy]

ok I think I have found out the problem..took inner part of shocks to yamaha for servicing (mostly because the tool is unavailable at the moment and just NEED to ride) anyhow dropped off at shop and 30mins later the guys at the shop rang me and have told me that the nylon sleeve near the lower valve assembly is cracked on both forks YAY..and of course it is not a replaceable part sooooo...expensive. on the up side it is the second one in two days that has had the same problem so the dealership is putting a case forward to yamaha for replacement even though the bike is out of warranty. sooo no riding for me for at least 2 weeks maybe more.... sigh always the way..what started as a blown fork seal is now much larger.

[Woody_393]

Ahh that sucks... but hopefully they foot the bill and get it fixed for free.

Good call on taking it to the shop, you may have never found that... Not sure I would have.

[boydy]

well Yamaha has replied with a ..."not our fault" saying that cracks in the assembly are caused by a hard landing if the forks have been overfilled with oil...seeing as though this is the first time a seal has been replaced or the units disassembled this tends to annoy the hell outta me. so now I'm hunting around online to see if i can find any aftermarket solutions. if not it's going to cost me $487 for each unit......so anyone with the new kyb forks be warned about over filling your forks if you do your own. will post a pic of the damage later and let you know if I come across a solution.

[boydy]

[yzernie]

That looks pretty serious to me. It appears that didn't just happen overnight. Not knowing what riding or maintence has been done on the bike I could undersyand why Yamaha says no.

[Woody_393]

Ouch, the price tag sucks and that does not look good.

[boydy]

all good found a place that will supply both nylon sleeves and shipping for $100USD so i'm pretty happy if anyone else has similar problems [Only registered and activated users can see links. ] these guys helped me out and were really helpful putting up with my tirade of questions

[Woody_393]

The owner (or one of the owners) frequents ThumperTalk and is a very classy guy. I'm glad to hear you found them and they hooked you up. That's a LOT better than the near $1000 you were previously looking at.

Nice find and thank for sharing the link.