installing cylinder base gasket, lower cam chain guide - best practice?

[Paul LeClair]

another stupid question(s)

because of the time this engine sat outside, and the various (thankfully minor) rust issues, I have been inspecting every aspect of this assembly/rebuild in minute detail.

first question. The lower cam chain guide is the original white/yellowish original from the Laverda factory. As part of the rebuild I ordered ALL consumables and wear items, including new cam chain guides. Comparing the new lower cam chain guide it is obviously a modern reproduction, in a different plasticky material, but also thinner by 1 mm. While I doubt that 1 mm thinner is going to make much difference, it did raise the question in my mind as to whether the original part, still in good condition, might actually be a superior quality part and maybe should be re used? Opinions? See photo.

second question. The bottom of the cylinder barrel has flow channels in it to direct the oil, which channels get covered over by the base gasket. After meticulously cleaning the old gasket debris from the base of the barrel, I fitted the brand new base gasket, only to observe the two holes to allow the upward flow of oil up the barrel to the cylinder head, are only half revealed by the corresponding hole in the gasket. I went to trim the gasket to increase the size of the hole, but then looked at the old gasket, and realized it fits EXACTLY the same way. Then I offered up both the old and new base gasket to the top of the crankcase, only to find the holes inb oth old and new gaskets line up perfectly with the holes in the crankcase. See the photos. In other words, the actual holes in the upper crankcase half do NOT line up perfectly with the oil channel in the base of the barrel.... seems very odd. Comments, suggestions? Should I trim the gasket to open up the hole in the gasket? The fit really is terrible, but if I open up the hole in the gasket the actual opening still will not be lined up exactly between the actual metal parts. I was actually thinking about taking a Dremel and "improving" the fit between the actual channel in the barrel and the holes in the crankcase.......

Paul LeClair

 

[nick7]

I think you are right to be concerned about the tensioner....speaking as one who has found half a blade in the gearbox, preventing first gear selection!not at all unknown apparently. Seems odd to me that they need to be bent too. Last one was sourced from Keith and of good quality...maybe somebody can confirm the best sources?

 

[Paul LeClair]

I think you are right to be concerned about the tensioner....speaking as one who has found half a blade in the gearbox, preventing first gear selection!not at all unknown apparently. Seems odd to me that they need to be bent too. Last one was sourced from Keith and of good quality...maybe somebody can confirm the best sources?

Hi Nick

at least the cam chain guide you are talking about is easily accessible and can be removed with engine in frame by just removing the cam cover and undoing a single bolt. The lower cam chain guide I am referring to is in a cavity in the cylinder barrel, trapped on the top by the cylinder head and trapped on the bottom by the upper engine case....

Paul LeClair

 

[sfcpiet]

Paul,

By all means install the new chain guide!

The originals become hard and brittle after being soaked in engine oil for decades.  Even if all 4 tabs are still intact, resign it to your trophy cabinet.

Have been installing the shown silvery grey items for the last 5-6 years, no issues whatsoever.

piet

 

[Paul LeClair]

thanks, Piet!

Paul LeClair

 

[CLEMTOG]

what about those gasket holes then?
CLEM

 

[Paul LeClair]

what about those gasket holes then?
CLEM

thanks, Clem, I am still hoping for a reply on that, the barrels are not going on the case until I resolve that concern.

I got the old base gasket off all in one piece, and when I put it back on to compare what is odd though is that the original base gasket in the motor from the factory is exactly the same way.

Paul LeClair

 

[Grant]

If it worked from the factory days until now, what's the problem?

 

[laverdakeith]

Can't see any issue with the new gasket in the pic the holes look clear, looking at the pic of the original gasket it is impossible to tell due to parallax, push the gasket right down onto the face and have another look if you have not already done so. If it is causing you to loose sleep then trim the offending area of the gasket.



    Keith

 

[sfcpiet]

Just drain holes, allowing the oil to return to the crankcase.  If anything catches on the gasket edge, the ensuing blockage will be the least of your problems.

Stick it together and all will be good, no need for tranquilizers either... Laverdas are not bloody rocket science!!

piet

 

[paparracas]

ask him to Patelo.
I think he has experience.
Greetings. 

http://www.youtube.com/watch?v=_STaG6Tu_Oo

 

[ScottMellor]

So the real issue is the oil holes in the actual metal bits don't line up.
I would be tempted to dremel them to help ensure best flow.

 

[Paul LeClair]

So the real issue is the oil holes in the actual metal bits don't line up.
I would be tempted to dremel them to help ensure best flow.

already done, I just couldn't put it together with a mis match.

I have never noticed this minor issue on other Laverda triples, but maybe I was not looking closely enough.

while waiting for new piston gudgeon (wrist) pin clips to arrive, I have bead blasted upper and lower triple trees, painted in high gloss black epoxy, then two coats of high gloss clear epoxy, and I just finished building up the three Brembo calipers from the six halves that were thoroughly cleaned out in the ultra sonic, all new internals including new seals, new caliper pistons, and new sintered brake pads. Given the amount of time/labour and parts costs involved to rebuild three calipers, might have been cheaper to just buy three brand new loaded calipers, probably what I will do "next build"........

Paul LeClair

 

[Grant]

New calipers only available with larger single bleed nipple so I am told.
I like bringing them back from the dead.

 

[Paul LeClair]

New calipers only available with larger single bleed nipple so I am told.
I like bringing them back from the dead.

Hi Grant

yeah, something to be said for raising the ones that came on the bike back from the dead, but as you know, and for those who haven't done it, it is considerably more work than might be expected. I still can't get over how much crap continues to come out of the caliper halves in the ultrasonic, long after they look clean. I cycled each pair of caliper halves through three different tank solutions, then in clean water, before stuff finally stopped coming out.

however, I really should have sent the caliper halves out to be stripped and re anodized to really make them look new, didn't, just sprayed them with that weird product from Harley Davidson to make black stuff like new and shiny again.....

Paul LeClair

 

[Davo]

I stripped mine completely, gave them a rough clean and then sent them off to a guy who does aeronautical parts cleaning and coating. Had them chemically stripped and cleaned and then anodised in black. Then new pistons, seals, nipples and bolts. Came up like new except for the rear caliper which insisted on weeping around the bleed nipples. Put it in a box for later thought - probably helicoil the threads as previous owner had taken it out to 7mm threads - and bought a new single bleeder item from Steve at Bevelheaven. ironically the new caliper was about the same price as a rebuild kit.  :