upper bevel help

[double diamond]

When the cam nut is tightened, the cam gear should be contacting the cam bearing inner race. There should be no axial clearance. If you feel any axial play, it could be the bearing or something is hanging up the gear and preventing it from making contact with the bearing.

Matt

[Scottish888]

Thanks,

All new bearings in this engine, I think when I nip up the cam nut with the cam locking tool I can eliminate the current axial play.
The final part of a slow and complex engine build, I appreciate the help of all who have contributed to my learning experience with these engines.

Regards,

Alex

[ducwiz]

Pls also make sure that the camshaft bearing has no axial play in his seat in the head. You might have to heat up the whole assembly to get it loose and checkable for play. Possibly, you can measure play by a feeler gauge blade engaged between the bearings outer race and the Seeger circlip.

cheers Hans

[ranton_rambler]

I’m not an expert by any means as I’ve only done one engine, but it seems OK!
I just nipped the camshaft nut up lightly to check the bevel meshing. As Matt says, the gear should slide up to the bearing, maybe needs a little tap to settle it. Perhaps check your key and keyway slots are OK. I left the locking washer out at this stage to make life easier and I only fitted the end cover temporarily just to keep everything in line. It was pretty difficult to get it off so just a precaution in case it all needed to come out again.

Actually it will need to come off sometime as that’s one of my 2 minor oil weeps.

[Scottish888]

a local motoscrubs member (themoudie) was kind enough to lend me a cam tool to finish this job and I could not have made progress without it.
I think I am nearly finished with the upper bevel setup but would like a bit advice. Got all the various shims moved around/changed until the bevels turn freely and have good mesh at the grind marks with good alignment and no backlash. Tightening the bevel tube screws further affects the mesh a little, how tight should they be?
At the moment the tube is screwed up tightly but I could get a bit extra by a hand allen key if I try, I find this affects the mesh a little at the grind marks. The bevels turn freely but with a little tightness at the grind mark area, not by much though but you can feel the difference (I am talking about moving the bevels with a pinkie finger, very light pressure)
The flange with gasket are good with no feeler able to enter the gasket area (using 2x 0.4mm thick gaskets, one gives too much play)
Should I use Loctite then tighten the bevel screws until the point of zero backlash (screws are still in quite tight but I could go a bit more) at the grid marks or no loctite and tighten it a bit more and a slightly tighter mesh only at the grind marks, difficult to describe the tightness I want to apply to the screws...maybe over thinking this too much

[themoudie]

Aye Alex,

I would use 6-7ft/lbs (8-10Nm) torque, no more, on threads that are clean and then given a "colour coat" of copper grease, using a small artists brush to apply. Nae muckle gobs of grease! If your active mind still seeks the safety of Loctite, again a wee drop (this will be sufficient to lubricate as well) afore tightening.

The double gasket is probably giving you that wee bit of 'bounce' when tightening. If you can avoid the 'tight' feel when the ground faces are flush and the set screws torqued that is what I would be looking for.

Deep breath and return to the fray! Nigel Lacey might raise an eyebrow or concur? But I suspect he'll be across at the ClassicTT (Manx).

Regards, Bill

[Bevel bob]

Some time since I did mine but I think 2 gaskets could be a mistake ,the total thickness of the shim pack could be correct but its distribution may need changing, How about only one gasket and transfer shims to lower the gear the thickness of the extra gasket.Probably need a good selection of spare shims. Its entirely likely that any or all of the shims that came with the motor have been misplaced by a PO. It took some time to get my brain "dialled in" at my first attempt to build the motor and I am too embarrassed to describe the cock ups that I perpetrated on the poor thing.That was 5/6 years ago and the motor has been fine for 60 days of touring the IOM and 60 laps "parading" at up to 9000 rpm so can't be too bad. Wonder what the next owner will say about it !!.

[themoudie]

Aye Bob,

My mistake, I should of emphasised the single gasket to Alex, rather than refering to it as "that wee bit of 'bounce' when tightening".

Thank you for clarifying.

My regards, Bill

[Samurai]

Yes, bolting the head down to the correct torque is essential to ensuring that the bevel gears are correctly shimmed. 'Nipping up' is not sufficient in my experience, you'll be surprised how much slack is taken up when doing this.

If you think you've got the shimming just right and then bolt the head down properly, the chances are that you won't have sufficient clearance and the bevel gears will quickly become damaged.

Same goes for the crank shimming etc.

[Scottish888]

Hi All,

I have to have the correct gasket thickness to get the bearing carrier to seat securely in the housing and prevent oil leaks from the top bevel tube flange, gap was average 0.8mm when bolted up without any gaskets. Only had 0.4mm gasket paper so had to make two new gaskets.
To have no gaskets I would need to machine out the top bearing housing to allow the bearing to sit a bit lower, I think there must have been a lot of machining variation in this area so some may need thick or thin gaskets?
I guess could leave out the gaskets until I finished setting up the bevels then add them in later or use sealant but I think best to adjust with everything in place as did not want to warp the flange.
It would be nice if there were gasket shape steel shims or various gasket thicknesses available to overcome the machining differences.
I am nearly there with the adjustments, I found that by moving a 0.1 mm shim I cam have a little backlash or tightness at the grind marks, I was about to settle for the little backlash when local Ducati forum member themoudie kindly informed me there are 0.05mm shims available.
I have ordered up some shims this morning so hopefully the 0.05mm will be just what I need.
Pic is with little backlash but grind mark alignment looks quite good, where should I add adjust next, behind cam bevel or upper bevel gear?

upper bevel_edited.jpg