I have over the last few days been pulling down my 21 se engine, and as a newbie am finding it a joyous, but at some points agrivating experience. Having struck the later with regards to the clutch hub nut i did a search of this forum to find i have not been the only one. I welded up some old plates as recommended to hold the hub in place however found it a little awkward to apply enough holding force, decided then to weld come tabs onto the plate which i then held in place using 3 bolts retained by where the clutch cover attaches (i hope this dosnt damage the clutch casing when force is applied to the nut). I then swung on the socket...swore....added exstension bar......swore.....WD40....more swearing. Nut wont budge (dont worry i have prised out where the nut taper is punched into the keyway). I really want to make sure so question is, can a rattle gun be SAFETLY used to remove this nut and is it common practice(my crank seems to be in good condition, and i dont feel like buying another one )
I also have another question relating to the rebuild, is it completely necessary to replace the crank seals when pulling down the bottom end or only when replacing the crank. How can you tell if they are in good condition.

Thanks (more questions to come no doubt)

Yes, you can use an air gun to undo the clutch centre nut. Do it back up with a torque wrench though!

DON'T use the gun on the primary drive gear on the end of the crank though! It probably wouldn't do any harm, but you wouldn't want to risk it!!
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Andy.
NSR-WORLD.COM

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sheamuz wrote:necessary to replace the crank seals when pulling down the bottom end or only when replacing the crank. How can you tell if they are in good condition.

They are so cheap, it would be silly to not replace them. You'll kick yourself later when you button things back up only to find the crank seals leak. That goes for any seal on a engine when you rebuild it. IMO

And like Andy said - nut off with gun is ok. Use a torque wrench when tightening. I would also recommend a new nut, just to be safe.
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Andre E. Benguerel
1996 Honda NSR250R
Daijiro Kato/Fortuna Replica #74

2000 Honda RS250R (NX5)
2008 Honda RS250R (NXA)
AFM Expert #430

Definitely replace the seal!

As the other guys have said about removing the nut. I had to do that a couple of months ago, and torque wrenched it up.

Where in Melbourne are you?

thanks for the replies . im actually in ballarat (i like to think of it as an outer suburb of melb ). Ill be looking for rebuild parts in the coming weeks. I think i no of two places in melb that supply them, b components in collingwood and southern cross sports in west heidelburg i think? where do you get yours, recommendations?

Stay away from B Components. He's be ripping people off. There is a huge thread here on him. Taking money and not delivering parts, not a good mate.

The most reliable source for NSR250 parts over the last 9 or 10 years, by far, has been TYGA Performance.

Yes, they are friends of mine (which seems to irritate some people that visit here for some reason), but facts are facts. They produce/supply good parts (both original and OEM), and they consistently deliver. TYGA is run by two "hands-on" English guys in Thailand, have a decent number of staff dedicated to various tasks like manufacture, shipping and handling, and admin, and now even have their own small manufacturing facilities for many parts.
_________________
Andy.
NSR-WORLD.COM

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Please DO NOT PM me for technical advice. My time is precious, and you will probably receive a faster response on the Forum anyway.

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How's life in the 'Rat? I'm on the eastern side of Melbourne, so unless you're really really stuck for help, it's a bit too far for me

A third (and cheaper) place is ****.com he's in Deer Park, and closer to you. ****** specialises in RGVs but he has NSR consumables in stock. PM me if you want his mobile, and tell him I said hi (I bought a dry clutch rebuild kit for a mate off him).

It does pay to shop around though, and if a reputable internationaldealer is cheaper and you're not short for time, it may be worth it....just factor in postage costs.

sheamuz wrote:thanks for the replies . im actually in ballarat (i like to think of it as an outer suburb of melb ). Ill be looking for rebuild parts in the coming weeks. I think i no of two places in melb that supply them, b components in collingwood and southern cross sports in west heidelburg i think? where do you get yours, recommendations?