Clutch centre removal

[muskrat]

G'day K1100. The shock of the blow does help. Quick heat fron a torch is better as the shaft doesn't have time to expand as well.
Cheers

[KiwiGF]

Any PO might also have done what i have done which is use loctite bearing retainer on the taper and heat makes that soft not too much heat maybe 200 deg c, i have the 6 spring clutch and it needs all the help it can get to stay in one piece and the keyway on the mainshafts are often not perfect mine certainly isnt so thats why i use the loctite

The bsa style extractor i bought from draganfly was not made in soft metal and has done job a afew times now,, the more years a centre is is on the harder it will be to free i guess

A tap on the puller is a good tip but not too hard as it could damage the ball races etc

[BSA_54A10]

I have a full set of removers for BSA clutches.
There are 7 of them.
Most are CEI ( 26 tpi )
However one has 24 tpi and another is 20.
All of them will screw into the hub and bottom out with little more than heavy hand force.
If you can not screw the puller in till it either bottoms out or shoulders out then you are using the wrong puller.
The threads are all parallel .
Think of them like you would any nut & bolt.
If it only goes in 2 or 3 turns then you have mismatched threads ( or badly damaged threads )
The parts books all list the corrct puller by BSA part number and Lightning spares list their pullers also by BSA numbers with a description ( length, tpi & thread type )

[K1100]

The thread has stripped on the second extractor. There is barely 3 mm to screw in to, which must be part of the problem. I have tried heating the clutch centre with my propane torch, I have tried a sharp smack on both sides of the centre while the extractor is tight, and I have tried a gentle smack on the end of the extractor nut. I don't have welding kit or contacts with welding kit so I am starting to feel low about this!

I have just re-read everyone's earlier suggestions and realise that I haven't tried a  bearing puller yet so I've ordered one of these.

[bsa-bill]

I bought a centre from someone (sorry can't recall) and returned it without trying it due to the lack of thread for the puller to engage similar to your problem K1100
as I recall there were barely two full threads, the seller took it back without problem, as I recall him saying he had never had a problem with them I wondered at the time if it was me, but the replacement I bought elsewhere had a lot more thread.
Looks like there's maybe a bad lot out there

[A10Boy]

Mine had the right thread etc, it just wasnt bored deep enough. Drilled it out 1/4 and it fits just right.

[BSA_54A10]

It happens when some "evilbay expert" send a part they bought from another "evilbay crook " to a factory in India with 1000 Rupee and a note "make as many of these as you can ".
Another Evil bay b arron then sends one of these to China because Indian parts were too expensive.

[K1100]

Well, it's off, using a bearing puller, and with the most almighty bang. It needed so much force that I was in a cold sweat when it eventually freed. There was no Loctite ....

In the picture is the bearing puller, £14 from RS, and the two clutch centre extractors. They are different, from different suppliers .... though I gave the same information for both. One is stamped MCA P127 and the other MCA P246. The threads on both stripped ... P127 is short because I sawed off the damaged thread section to try to use it again. I have tried to measure the tpi but there is not enough thread for me to do it ..... P127 seems to have more threads than P246. (i.e it is finer). P246 fitted better but there is so little thread inside the clutch centre that I think both were doomed to fail. Is it possible to get extractors made from properly hardened steel?

(PS Beezermac .... I couldn't find the mini-puller you suggested in stock anywhere. I am sure it would have been better and avoided the Big Bang)