to Roll or to Ball........

The Cylindrical bearings are indeed superior to that of the ball.

Proper installation (Correct running clearance and alignment) of Cylindrical bearings is critical. Get it wrong and early failure is likely.

Ball bearings are far more tolerant regarding running clearance and axial alignment.

In short:
If you have the provisions to insure proper cylindrical bearing set up by all means use them. http://www.husaberg.org/modules/Gallery ... .sized.jpg

Hope this helps.

Kind Regards,
Dale

heimar

i got that one right then thor! anon

any kind of half decent tool makers will, if prepared to do a 'fiddly little job', be able to check your cases for trueness. take them to the toolmaker empty of everything - especially outside dowels etc. give them the crankcase screws and the dowels and they will check them.

someone came up with the info that there are infact oversize main bearings that are only .5mm or was it 1mm bigger than the originals. i'm speaking as someone who hasn't done this so it's only theory.

so you need to find out what you would do if the holes for the mains aren't true...

someone here will know about these oversize bearings i hope. UHE members....help!

the top of my cylinder has a drop from one half to the other that you can hook a finger nail on! so there is so much you could 'blueprint' if you wished too.

Taffy

As a result of each case section having a main bearing retention lip bearings or a suitable spacer must be installed prior to confirming axial main case bore alignment.

Cylindrical bearings can be ordered "ground to size" for compensation regarding variations in crankshaft axle OD and main bearing bore ID.

Spacers of varying thickness are used to control axial crankshaft float.

Lower end set up as described including custom ground main bearings runs aproxiamately $400.00 US


Hope this helps.
Best Regards,
Dale

I agree with Dale. If you measure accurately the ID of the Case and the OD of the crank, then you could supply this to the afformentioned bearing place and have them grind you bearings with proper preload.

What is preload? When you press the bearing into the case, the outer race with "shrink" a bit, lets say 0.001mm. When the crank is pulled/pressed into the bearing, the inner race will expand a bit, let's say 0.001mm. The balls within the bearing need a certain amount of room to rotate. If there is too much preload, then there is not enough room for the balls to rotate, and you will get premature bearing failure. Same goes if there is too much "slop" in the pressed surfaces.

I have a feeling, that along with the case alignment, that this may be a major hidden contributor to everyones premature crank bearing failure.

Dale, would you explain this statement a bit further:
"As a result of each case section having a main bearing retention lip bearings or a suitable spacer must be installed prior to confirming axial main case bore alignment."

What does one do if the cases don't align (would this not yield catastrophic failure straight from the manufacturer)? Is there a shim one would use to fix, or would one need to match up with another case?

Hi Luke,

Main bearings must be installed from the inside of each case halve.
Each bearing is pressed in until seated against a shoulder which is part of the main casting. The bearings are then retained via the crankshaft and said shoulder.

On rare occasion when the axial alignment is out of specification I use a fixture which indexes off of one case halve in order to bore the remaining case halve on center. This creates an oversized bore which requires an oversized outer bearing race. However, improper bearing fit, misaligned crankshaft halves and excessive end float are the most common cause of premature failure.

Hope this clears things up a bit.

Best Regards,
Dale

Ps
I have yet to encounter a set of Husaberg engine cases and / or a crankshaft combination which provides for the proper clearances when using off the shelf cylindrical bearings. I always end up using custom bearings.

Dale, do you space between the bearing and the case, or between the bearing and the crank, when the axial float is out of spec?

Parsko said:

Dale, do you space between the bearing and the case, or between the bearing and the crank, when the axial float is out of spec?

Click to expand...

Lineaweaver modified crankshaft and auxilary drive

Note bearing spacer and cylindrical main bearing inner race.

As pictured I make a custom spacer from bearing stock when removing the balnce unit. Otherwise I use OEM shims to control end float .

I average one maybe two crankshaft / case upgrades per month.

Dale

Gentlemen,
With all due respect "this is not news"
Since early 2003 it has been common knowledge (at least I thought it was) that chronic main bearing failure was as a result of improper running clearance and misalignment.

Perhaps the earlier discussions were lost with the great crash of 2004. :?

Sincerely,
Dale

kindov dale

i thought it was us guinnea pigs in europe that told you in the americas how '****-up' things were? i think the problem is that it came drip fed and all in the NA said "well, we'd just appreciate having the bikes!!!!!"

it'll come again.

Taffy

Hi Taffy,
While you Europeans were blowing up 03 and 04 lower ends I was hard at work retrofitting pre 03 model Husaberg engines with cylindrical main bearings. Hence the knowledge gained which I have gladly shared.

Sincerely,
Dale

Dale,

For the record, do you use roller or balls on the mains?

(you may have mentioned this before... I assume rollers)

-Parsko

appreciated dale

someone else over here was telling me that gas-gas and husey cram their bearings in too tight.

Taffy

Hi Luke,
As per the picture earlier in this thread I use custom ground roller units.
Dale

Dale, the question I (and possibly some others) would like to ask is, if you were Joe Bloggs building his engine in the shed at the bottom of the garden with no engineering shop and no extra money to send the job out what would you use? Rollers, higher load capacity but need perfect alignment or rollers not so critical alignment, but a lower load rating.
Just a thought could you use one of each on the crank??

Thanks

Yosh

Hi Yoshie,
Premium quality C3 Ball.

Hope this helps ease your mind a bit.

Best Regards,
Dale