Crankshaft & Big end white metal refurbishment specialists (Longstroke) ?

[Stephen Foster]

Has any forum member had the white metal on the big ends refurbished & crank ground please ?
If so Who offers this service & were they happy with the results ?

Also interested to hear about camshaft reclamation ?
 
My Own longstroke "Star Twin" is probably fine but I have a spare bottom end I would like reconditioning .
Preferably U.K but I am interested in any feedback please .

Best Wishes,
Steve ...

[groily]

Hi Steve,
I just had an early 5T engine done by T&L Engineering in Beds. £100 a rod to remetal and finish, and a few quid for the journals, which just needed a polish in this case, and a a few ££ more for the fasteners etc  They reassembled the crank, which I sent split. Very nice job by the look and feel - but the engine isn't together again yet. Maybe worth calling on 01234 352418? - ask for Barry or Derrick.
Cheers, Bill

[Stephen Foster]

Thanks Bill ,
Thay are on My list to contact !

Best Wishes,
Steve ..

[trevinoz]

Steve,
              The big ends are replaceable shells.
I am in the process of rebuilding my Star Twin engine. Just got the crank back yesterday.
For the timing side main I used a later bearing with the removable insert and replaced it with a leaded gunmetal bush which the machinist bored to fit the crank.

Trev.

[Briz]

Not on the real early ones Trev. They had one-piece rods and a clamp-together crank. A really horrible piece of engineering!

[trevinoz]

And they only made about 500 of them and I doubt anyone on this forum has ever seen one. Have you, Briz?
I would like to see one for curiosity sake.

Trev.

[Stephen Foster]

I apologise to the forum ...My mistake .
The crank on My "Star Twin" IS the replaceable shell bearing type .

I had been misinformed earlier & was preparing for for an engine rebuild in advance ..still nice to learn about specialists for future projects .

Best Wishes,
Steve ...

[Briz]

And they only made about 500 of them and I doubt anyone on this forum has ever seen one. Have you, Briz?
I would like to see one for curiosity sake.

Trev.

Yeah; there was a bloke at the Newark autojumble a year or so back with a crank assembly for sale.I'd never seen one before that though.
There was a pair of rods on ebay too not so long ago.
Me, I'd do whatever it took to get the later crank assy in there!

[Brian]

According to Munro's "BSA Twins" book there were no more than 200 of them produced. I have certainly never seen one.

I have rebuilt a crank for a early 3T Triumph which are also a built up crank and they are a mongrel to do. If I ever come across one I would replace it with the "later" crank.

[kiwipom]

hi guys, when i first saw this picture of the original cranks i personally thought that they would be better, you could have needle bearings instead of shells, why were they not continued? Cheers

[Briz]

Hmmm, now thats odd; the one I saw wasn't like that, it had the crankpins clamped into the flywheel with pinch bolts. Maybe it was out of something else. It was labelled as A7 though.

The reason you couldn't have needle rollers is that the outer parts which include the crankpins would have to be forgings and it would be difficult to harden them enough without compromising the rest of the structure. Not impossible these days I imagine.
A pressed together crank such as used on a lot of japanese bikes is a better way of doing a roller bearing crank.
But given a proper oil supply, plain bearings are just as good as rollers.
A one piece crank is much better as it cant go out of alignment.