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splitting crankcase
Posted: Sun Jan 12, 2014 4:59 pm
by ChrisD
Hi Guys
I am replacing the big end (also fitting sealed gearbox bearings and idler bushes and finally sorting out the worn centre-stand plates) so have removed engine and gearbox.
I have split the crankcase, removing the off-side (timing-chest side) easily. But I cannot get the drive side crankcase off the crankshaft. Is there anything holding it together that I've omitted? What is the circlip for? Or is it just that the bearing is rusted onto the crankshaft and will come off with a bit of heating and BFI? Any suggestions?
Thanks
ChrisD.
splitting crankcase
Posted: Sun Jan 12, 2014 5:54 pm
by Exile
Sounds like you're not the only one with this problem. Norm has the same problem..
See here:
http://www.hitchcocksmotorcycles.com/vi ... orumorder=
Read it through.
splitting crankcase
Posted: Sun Jan 12, 2014 6:44 pm
by ChrisD
Exile
Thanks, I read that recently. Mine is a 1996 500cc Classic and I don't know if the old types of bearings are different from the more modern ones. I suspect the drive side has but one bearing on mine.
ChrisD
splitting crankcase
Posted: Sun Jan 12, 2014 6:50 pm
by Norm
And I still have the problem, I will have another try today but I'm concerned about cracking the case. Chris what type is it, does it have the oil seal on the outside where you can see it? If it does there is nothing to prevent it from coming out unless the distance piece is stuck on the shaft or the outer bearing is stuck on the shaft. Any signs of rust? I can't see heating around the shaft helping unless you can get heat on the distance piece if that won't come free
splitting crankcase
Posted: Fri Jan 17, 2014 5:35 am
by ChrisD
Hi All (well, the two respondents so far).
Have resolved the problem and released the crankshaft from the nearside crankcase of my 1996 500cc classic (export).
I built a wood frame around the crankcase to support the aluminium/cheese and to lift the other end of the crank off the table, supported on a wood base. Screwed the nut back on the crankshaft threads, heated the crankcase up for half an hour with a hot air (paint-stripper type) gun until the oil traces smelled bad and the old gasket bubbled and used a 2lb BFI on the nut. The shaft slowly slipped from the tight embrace of whatever held it tight and is now free. Once its cool I'll check it all out.
Got my new roller bearing etc from Mr H now too, so smooth running (if the engineer can properly true up the crank) and the sealed gearbox bearings too so hopefully no more besplattering by grease+molyslip.
Cheers, ChrisD
splitting crankcase
Posted: Fri Jan 17, 2014 6:37 am
by Norm
Got to admit I gave up not wanting to damage the cases put it back together and it can go back on ebay. Don't like doing it but the owner didn't want me to risk breaking something
splitting crankcase
Posted: Fri Jan 17, 2014 1:57 pm
by p
I haven't tried it, and I guess your job is done now, but I wonder if one of these percussion drills at zero revs, or an air chisel fitted with a suitable "blunt" drift may jar something like this free without putting stress load on case? Any thoughts, anyone tried??
splitting crankcase
Posted: Fri Jan 17, 2014 6:36 pm
by Norm
P I tried everything I could think of to get the distance piece off the shaft but there was no way it was going to move without more pressure and that was going to either work or do major damage.The motor was running ok before I pulled it down and the reason I had to pull it down was because some of the barrel threads had been pulled out of the cases and the Indians had made up stepped studs and they had been pulled again because it hadn't been done properly as usual. It had to be set up in the mill and done so it was all square again
splitting crankcase
Posted: Sat Jan 18, 2014 9:07 pm
by Rich H
I have a Reddich 350 bullet with the circlips inside. I had the same problem and the
fellow who rebuilt my big end etc told me to warm up the drive side crankcase which will
expand a bit to release the bearings from the shaft. Belting it will do damage.