Author Topic: Am I going to regret not buying this crank?  (Read 2031 times)

Online Greybeard

  • Jack of all trades; master of none.
  • Wise & Enlightened
  • *
  • Join Date: Feb 2011
  • Posts: 6367
  • Karma: 35
Re: Am I going to regret not buying this crank?
« Reply #30 on: 24.12. 2015 17:26 »
...I had an idea alloy wheels came about from BSA...
I've seen BSA allow wheels. I didn't know they had any connection to our BSA.
Good Advice
0
No reactions

Online bsa-bill

  • Wise & Enlightened
  • *
  • Join Date: Mar 2006
  • Posts: 5512
  • Karma: 64
Re: Am I going to regret not buying this crank?
« Reply #31 on: 24.12. 2015 19:02 »
Quote
I've seen BSA allow wheels. I didn't know they had any connection to our BSA.

And I think you are right to think so, they are I think a Malaysian Company, no I came across some reference to BSA expertise in metallurgy (and alloys - DOH) which I can't find at the moment, but the depth of knowledge of metals needed to compete in all the fields they did speaks for itself really
Good Advice
0
No reactions
All the best - Bill
1961 Flash - stock, reliable, steady, fantastic for shopping
1959 Rocket Gold Flash - blinged and tarted up  would have seizure if taken to  Tesco

Offline nimrod650

  • Valued Contributor
  • ****
  • Join Date: Feb 2015
  • Posts: 446
  • Karma: 4
Re: Am I going to regret not buying this crank?
« Reply #32 on: 24.12. 2015 19:18 »
Whether its right or wrong to buy and break up a good bike, has anyone noticed how Mr M B Transits' prices have gone through the roof recently? A good crank should only cost say £300.
same old story its worth what anyone will pay and if he can get £1000 mine must be worth A £1000 you will get someone asking £25000 for a  r.g.s  and soon they are all £25000 plus thats life
Good Advice
0
No reactions

Offline nimrod650

  • Valued Contributor
  • ****
  • Join Date: Feb 2015
  • Posts: 446
  • Karma: 4
Re: Am I going to regret not buying this crank?
« Reply #33 on: 24.12. 2015 19:40 »
regarding cranks on british bikes and the final chapter without wishing to upset anyone by swearing the last norton twins that were made the cranks were taken to a local firm  to be ground as the factory machines were worn out
Good Advice
0
No reactions

Online morris

  • Wise & Enlightened
  • *
  • Join Date: Aug 2012
  • Posts: 1634
  • Karma: 26
  • Antwerp, Belgium
Re: Am I going to regret not buying this crank?
« Reply #34 on: 24.12. 2015 23:19 »
Keep it coming lads. Love the way this post is heading...!
Good Advice
0
No reactions
'58 BSA A 10 SA
'52 BSA A 10 Plunger
'55 MORRIS ISIS
The world looks better from a motorbike
Belgium

Online BSA_54A10

  • Wise & Enlightened
  • *
  • Join Date: May 2008
  • Posts: 2030
  • Karma: 32
    • BSA National
Re: Am I going to regret not buying this crank?
« Reply #35 on: 25.12. 2015 00:40 »
Trevor,

Thanks for that great answer. Very intereisting discussion of grain structure and testing methods. Takes me back to the one materials class required when your major is Electriclal Engineering. This brings me to another question. I'm digging down because my next rebuild will most likely include journal welding. If I understand it correctly, forging changes grain size, shape and orientation to increase strength. In a crank, I assume the added strength is for both torsion and bending. So, the question: would 2mm (or, even more) of grain-structure change due to weld penetration make much difference in the overall strength that has been added core-deep by forging?

Sorry if seems I'm trying wear out your fingers with typing.

Richard L.

Yes you are correct.
Metal spraying will yield the strongest crank.
However BSA cranks were way over designed so a moot point about drop in strength due to changes in grain structure caused by the welding.
Get the finished product nitrided and it will be more resistant to failure than it was when new.
Be sure to tell whoever is doing the build up you are going to nitride it as it might make a difference to what they use to do the build up with.
For all I know they could use a nitrogen wire to do the build up so you get a double benefit.
Good Advice
0
No reactions
Bike Beesa
Trevor

Offline A10Boy

  • Wise & Enlightened
  • *
  • Join Date: Jun 2008
  • Posts: 1075
  • Karma: 11
  • Solihull, Near Birmingham England.
Re: Am I going to regret not buying this crank?
« Reply #36 on: 26.12. 2015 12:04 »
Apologies if someone has already mentioned this but they were EN49B

Good Advice
0
No reactions
Regards

Andy

1958 Super Rocket
Plus
1974 Kawasaki Z1a
Yam XJR 1300

Online cyclobutch

  • Wise & Enlightened
  • *
  • Join Date: Aug 2010
  • Posts: 1549
  • Karma: 14
Re: Am I going to regret not buying this crank?
« Reply #37 on: 29.12. 2015 13:21 »
h no, does it mean i will have to insure the crank separetely from the rest of the bike ? as its agreed value only

Well I suppose it would be another item you should point out to them as a modification whether it has been sprayed or welded.
Good Advice
0
No reactions
Warning - observations made by this member have a 93% unreliability rating.

Of Bikes; various, including ...
'58 Iron Head Flash Bitza