Engine Bearings for a 450 Widecase

[captainkcorb]

Now that the bearings are out, here's what I've found. These apply to widecase engines from engine number 108621 (250cc), 11052 (350cc), and 453509 (450) according to Mike Walkers book. The first widecase engines had a smaller bearing on one side of the crank. The bearings have a variety of markings and it took an eye loup to read much of it but here's what was there.

Both main bearings are 72x30x19 mm. Both should be 'C3' clearance. One has a circlip in a groove and are marked as follows:

With groove: n RIV 78DY30 = 6306NR car.650

Without groove: n RIV 7830 = 6306 car.053

Two gearbox bearings were 40x17x12 mm and marked as follows:
RKW 6203
RIV 01APL car.580 (this bearing had one metal seal)

Two were 47x20x14 and marked as follows.
RKW 6204RS (this bearing had rubber seals on both sides)
RIV 1A20 = 6204 car.053.


Original post:

With some embarrassment I realize it's over two years since I started this project. While the running gear is now fully refurbished and looking great, it's only recently that I've finally girded my loins and heated the cases to get the bearings out.

My questions are where should I go for a full bearing set for this engine and is there a list of the proper bearings. Some I can read and they appear to be relatively common. On others (like the main bearing with the groove and circlip) there is nothing legible.

I've gleaned a little knowledge from the web (like they should be C3 spec) but a full list I could take to Canadian Bearings, or better, a source that's been used by the club, will be well appreciated.

Thanks in advance,

Brock in Maple, Ontario
captainkcorb@gmail.com

[cm250to999]

I know there are folks that will have more help to give. For the fun of it, I'll chime in anyway. I was able to use kimpex snowmobile bearings in a 250 narrow case that I raced years ago. That poor beast did amazingly well on a shoe string budget.

I'd love to hear more about how the factory race bikes used spherical contact bearings (similar to what the twins use today), while the production bikes used standard ball bearings. The big difference is that with ball bearings the crank needs a few thou of end float, since the bearings are not preloaded with thrust (and are not designed to be). Spherical bearings will not maintain alignment without preload.

Anyway, I did find this link below. Not sure which model applies.
http://www.ducatimeccanica.com/#manuals
Right main listed as RIV 78BDY 30x72x19 (with groove)
Left main is RIV 3A 30x62x16

I think a good bearing house should be, or use to be able to cross RIV bearings. Part of me says RIV became part of SKF, could be wrong.

Good luck
I am sure there are a number of outfits to help, bevel heaven may be a good start.
Chris

[Chris Collins]

I believe Dave Gooch has a complete list of replacement bearings for Duc singles - Dave

Edit : Oops, sorry - I guess Dave doesn't have the list for singles

[captainkcorb]

Thanks Chris and Chris. I'll use the info on the mains at the bearing shop, and the others seem more common, or perhaps less critical. If Dave chimes in that will be great too.

I've put the right case half in the stove for the bearing removal treatment as the left half went to well (and looks so great now that it's had some time in the blast cabinet with BT13).

The bevel shaft bearing carrier and the main bearing came right out. The rear transmission bearing came out with some persuasion, but the blind bearing is giving me trouble. I can't drift it out and can't get a grip on it.

Any thoughts? More heat comes to mind but the manual says 260 and I had it around 280 (on the questionable stove thermostat).

Cheers,

Brock

[The Goochman]

Sorry Chris,

I have some information on Pantah engines, but nothing on the singles. I could use the list if it ever gets put together though, I have 3 engines somewhere in the barn that will eventually need rebuilds!

Dave G
aka The Goochman

[cm250to999]

Blind hole bearing puller is the only trick I know. I bought a set from mac tools, can't remeber for sure, for about $250. I can pop that out at Iconic cycles / Ducati Toronto. If that helps.

There were 3 or 4 450 parts manual listings, the numbers I dug up came from the latest model. You might want to double check the dimensions match. More than likely they are all the same for 450, but I don't know for sure.

Chris McDermott

[captainkcorb]

Thanks for the offer Chris. I may take you up on it.

It occurred to me that I can TIG a threaded rod onto the inner race and use it as a puller with a pipe and washer. I think I'm going to give that a try first. I don't think the heat will hurt the case as it should be fairly well isolated by the balls and outer race. I'll give the case another session in the oven before I try pulling it.

I'll report back,

Brock

[captainkcorb]

It worked. All the bearings are now out and the cases ready for cleaning and reassembly.

Thanks again to Chris for the support and offer of assistance on getting the blind bearing out. I'll start another topic and post a couple of pictures on the procedure as it was quick and easy (providing you've got access to a welder).

Best regards,

Brock

[cm250to999]

Brock

Glad to hear you found a solution. Not that I see the singles much these days, I will be interested to hear what you find as far as replacement bearings go. For sure there are answers. I have a link to a web page at work for a guy in Europe racing a single that looked very well built. I hope you keep finding simple cost effective answers. Those are my favorite

CM

[Michel Roby]

Hi Brock...
I have been racing Duc singles, both WC and NC, for about a dozen years now... and still racing those.
Obviously, the best way to remove the "blind" bearing in your WC cases is to use a blind hole bearing puller. Princess auto has a good set that does the job perfectly... at a very decent price.
All the bearings are off the shelf bearings at any bearing place; just make sure you get C3 bearings from them, but this is what they mostly have anyway.
As far as I am concerned, in the "bearings dept", all Duc singles are pretty much bulletproof in relation with the size (oversize!) used... don't worry too much if you don't get top brands like SKF of FAG...
The only bearing you have to watch closely is the crankpin rollers... but again, they are cheap and easily available from a couple of sources in UK (Lacey Engineering and Alpha Bearings).
Have a look at Lacey Engineering's web site... they are specialized in Duc singles parts... and are very efficient at dispatching parts on this side of the pond... really good prices, friendly, always adding new parts to their inventory...

Good luck with your project, Michel