85 250sx Timing Chain replacement?? [Archive]

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ChrisG

03-17-2006, 08:21 AM

I am getting a very noisy top end - just adjusted the valves last week to no prevail - so I believe its time to replace the timing chain.

My question is I need to know everything I need to replace while I am in there. And a source where I can buy it besides the local honda dealer. Any specific tools like flywheel puller also (don't know where to get it).

Thanks

chris200x

03-17-2006, 01:42 PM

lol.. looks like we will be on our own??? I was browsing for you on www.hyperparts.com they have some of what you need. You should also check www.bikebandit.com they might have some things as well. I dont think youll have to buy the whole top end gasket kit as the only gaskets you'll probably need are the one for the cylinder head and stator cover. They flywheel puller can usually be baught cheap off ebay. I'm sure someone around here knows more about this stuff than me... ANYONE?? lol

But remembering back when I did my 200x I replaced timing chain (D.I.D) two tensioners, those gaskets, and a puller I think is all you really need. :wondering

Howdy

03-17-2006, 02:05 PM

I am having a brain lapse here ( no sleep ), but going from memory you don't need to pull the flywheel to replace the timing chain. It is actually on the other side of the motor. You will need to take off these parts: right side case, centrifical clutch, and I think the oil pump. You will also need to remove the top cap of the motor, and the timing chain tensioner.

As far as parts goes: There are a couple companies that made a aftermarket timing chain. I haven't bought a new one in years, so I can't say for sure what is still available.
Howdy

chris200x

03-17-2006, 02:19 PM

Hmm, I think your right, But don't you need some special tool to take the clutch and oil pump off?

Howdy

03-17-2006, 02:42 PM

Hmm, I think your right, But don't you need some special tool to take the clutch and oil pump off?

No special tools were used on the last one I took apart. sockets were 8mm ( or 5/16 ), 10mm, 12mm, and I think the clutch was 22mm. You can use a standard socket for the 22mm, I think it was 13/16.

Oh, and be sure to remove the dip stick before pulling the side case. It will get in the way if you leave it in.
Howdy

ChrisG

03-17-2006, 03:07 PM

Will have to replace the tensioner - correct? Any place to purchase besides bikebandit?

Can get cam chain at hyperparts.com -

broook

03-18-2006, 08:56 AM

You will have to remove "Both" clutches so as to remove the oil pump. Also if it has never been removed before you will need a clutch cover gasket as the factory one is stuck on really good. Don`t forget the left hand thread on the Man. clutch.

Howdy

03-18-2006, 09:10 AM

bigb9582

03-18-2006, 11:47 PM

get a D.I.D cam chain out of a Partsunlimited book at your local dealer. 67.00+tax. they only list the 250es and not the 250sx. same chain. dealers around here want 112.00 for a oem one.
use this link for the 250es bigred to help you out. http://deepa.recongamer.com/hondamanuals/index.html
when you remove the side cover be careful not to pull the kickstarter out of place.
the clutch closest to the front of the machine is reverse thread.
both clutch nuts are a pain to remove because the clutchs want to turn. what i did was push it up tight againt a sturdy wall with the front or rear (depending on which clutch i was removing), then put it in first or reverse. that way when you was trying to loosen the nut or tighin it, it would try to move and push against the wall not letting the trike move and the nut would break free or tighin up good.