Topic: Where to get CB500/550 big end and main bearing shells for historic road racer.

[peter400four]

I put this in the "wanted" section, but as I got a few views but no replies, I thought I'd try in the racing and performance section.

Mr Administrator, please feel free to remove if you feel it doesn't belong here.

We're getting to the business end of building a new motor for my Blanchard Flying Dragon homage and want to know if members know a good supplier of after market main and big end bearing shells.
This motor will have 550 crank cases, gearbox and clutch and the mains we need for that are EEEEE.
We're about to get into the crankshaft with a micrometer to check which shells we need for the big ends. Does anyone know which colour codes go with which diameters? The colour on the bearings out of the donor motor have long faded out of existence.
Thanks in advance.

[Rod]

Have you tried David Silver? they ship worldwide  https://www.davidsilverspares.co.uk/

[peter400four]

Thanks Rod,

I'll check them out.

[Tintop]

Very nice bike, and kudos to the pipe manufacturer.   Is that a Harris frame kit? 

[peter400four]

Thanks for your kind words Tintop
The whole bike was manufactured from scratch by Mike and Nathan Greene, of B-Spoke Designs, here in northern Tasmania and is an homage to a mid-1970s club-level TZ beater built in the UK by John Blanchard. Mike used a photograph of Blanchard's "Flying Dragon" from a British historic motorcycle magazine to redraw the original Harris frame and swinging arm with CAD on his lap top, using the known distance from crankshaft to gearbox output shaft to scale the whole thing.  They made the tank starting with a chunk of modding foam. The fairing, seat and front mudguard are from various TZ models and they used water forming to make the  pipes.
The bike has Dymag wheels, as per the original, and is powered by a bog standard CB500 motor (John Blanchard based his on a CB400 with 500cc cylinders and a supply of parts from HRC. It was a VERY special motor.)
We're now looking at going to the next level and building a more powerful motor that will still be reliable. Looking for around 60hp at the back wheel.
The head has been welded up so we get high compression with standard pistons and a more-even fuel burn. Just need the bearings and a cam with Yoshimura-type timing and the bike should be ready for our coming summer season in October.

[bwaller]

I haven't looked lately but recently Honda showed 500/550 bearing shells were NLA but the CB650 bearings were available and the same parts.

And yes, gorgeous bike and worthy project.

[turboguzzi]

real beaut!

just enter the stock part number in google and stuff will come up

for example

https://www.google.com/search?client=firefox-b-d&channel=trow&q=+13315-323-000

[peter400four]

Thanks for the input Bwaller and Turbo Guzzi.
Bwaller, That's good to know, that the 650 bearings are the same.
Turbo, I used that link you provided and found a dealer in Germany, CBFOUR, who lists the bearing shells as available. Just wrote to him so it's now a matter of receiving a reply and discovering whether or not he has the sizes I need.
Thanks again.

[turboguzzi]

just for your knowledge, several more modern non honda motors might use same bearing sizes, japanese industry often sourced from the same suppliers.... for instance, connecting rod bearings off a GSXR 1000 can work on honda rods, same dimensions and they might have the full range of sizes.  going from memory here, but KZ650/750 crank bearings might be same size. youll need to spend some time with workshop manuals to cross check....

[peter400four]

Thanks for that turbo. I may well have to do that because the mob in Germany is yet to even acknowledge my inquiry, let along say whether or not they have the required bearings.

[Rod]

Peter have you not tried David Silver yet? their website is showing that they hold stock

[MRieck]

What color is "E"?

[Rod]

What color is "E"?

E is Red Mike

[peter400four]

Many thanks Rod, you've come through on two fronts. First up "Red" is the answer to the main bearing question, thanks. I did have a look on the David Silver site, but with the rate of exchange against the quid at the moment and then postage, I was looking at something close to $600 Australian (Aussie dollar's not worth much these days). I was hoping to find something less expensive in the 'States or here in Oz. I received one tip that led me to a German site, but they haven't replied to my inquiry (yet), so Mr Silver may yet be the go-to man.

[iomtt9]

Hi Peter, correct me if im wrong but are you using a 500/550 bottom end or a 400/4 bottom end, if its the 500/550 they dont make red colour shells for this model as far as im aware. Get back to me as im sure we still have some yellow crankshaft shells for the 500/550 left but will have to check.
Col

[peter400four]

Thanks for that iomtt9.
Yes, it's the 550 bottom end, clutch and gearbox we'll be using, not a 400/4, and 500 barrels to keep the scrutineers happy.
I have to say, I'm starting to get a bit confused (not exactly a first-time occurance either).
My 550 cases have "EEEEE" stamped on them and apparently, E means red.
Would it be possible for us to just mic up the journals and let you know the diameters, or do you just work on the bearing colours? The problem we have with colours is that the years have removed any last remnant of the marking.
Thanks again for your input.

[Rod]

Hi Peter, correct me if im wrong but are you using a 500/550 bottom end or a 400/4 bottom end, if its the 500/550 they dont make red colour shells for this model as far as im aware. Get back to me as im sure we still have some yellow crankshaft shells for the 500/550 left but will have to check.
Col

You're spot on Col, did some checking and Reds (E) were only listed for the CB350F

[MRieck]

Hi Peter, correct me if im wrong but are you using a 500/550 bottom end or a 400/4 bottom end, if its the 500/550 they dont make red colour shells for this model as far as im aware. Get back to me as im sure we still have some yellow crankshaft shells for the 500/550 left but will have to check.
Col

Exactly. My point when I posted. Good thing I have a cache of 550 bearings.

[scottly]

My 550 cases have "EEEEE" stamped on them and apparently, E means red.

As far as I know, cases were marked "A, B, or C"? The crankshaft should also be marked. Bearing selection is determined by both the case and crank markings. For instance, on a 750, an A case with an A crank calls for a yellow bearing.

[peter400four]

Oopps.
A bit of a delay here since the last welcome posts.
I'm on the road for a few months of travelling up and down the East Coast of Oz to get away from the dreaded Tasmanian winter.
BUT, before I left, I took note of the posts by Rod, Scotty, DRieck and IoMTT9. You're all correct with your colour/letter statements. I checked my crankcases quite some time ago and simply "remembered" the letter code incorrectly, an increasingly common phenomenon, I'm sad to say. My letter code is AAAAa, so when I gat back to Tassie, hopefully after the last frost has disappeared, I'll get back into the Great Bearing Shell Search. 🤔