Spub
Hero member
Red: Nice call re the post deletions, and I'll fess up to the gems I contributed, but I'm afraid Bob has likely fled the site for saner pastures.......
New member and thanks...
- Thread starter Bob Z.
- Start date
OneThinBloke
Hero member
- Location
- Oxfordshire, UK
Spub said:
Let's hope not, but if so at least he now has the heads up for Wolfgang, Scott and others to be able to help him out with his project.
James
Cosi
Hero member
- Location
- Kingscliff
I doubt it he seemed pretty level headed, MOST people are able to negotiate the diatribe
Ah, you guys are OK! As well as a wealth of knowledge.
Spent numerous hours getting the head cleaned up enough for inspection of the parts.
The rocker spindles came out easy enough with the tip on using a 6mm bolt and appropriate socket as a puller.
The rocker pads/spindle bushings/adjuster tips look OK.
The valves and seats are needing attention as expected.
Interesting the big inlet valves are steel while the exhausts are stainless (non magnetic).
The valve and guide clearance seem a very good fit.
The inlet guide garter seals were rock hard.
The cam chain adjuster nylon roller shows wear for the 23K miles on the bike.
The roller in the lower cylinder also shows wear.
Now the big issue is getting the pistons out of the cylinder bores. Stuck very tight.
I got the cylinder base gasket joint unstuck and I get about 1/2" of up/down movement when I bump the bike in gear.
I'll soak the tops of the pistons a few more days in the heat.
If that doesn't work I suppose the solution is? cutting the top of the piston out by drilling around the circumference?
Spent numerous hours getting the head cleaned up enough for inspection of the parts.
The rocker spindles came out easy enough with the tip on using a 6mm bolt and appropriate socket as a puller.
The rocker pads/spindle bushings/adjuster tips look OK.
The valves and seats are needing attention as expected.
Interesting the big inlet valves are steel while the exhausts are stainless (non magnetic).
The valve and guide clearance seem a very good fit.
The inlet guide garter seals were rock hard.
The cam chain adjuster nylon roller shows wear for the 23K miles on the bike.
The roller in the lower cylinder also shows wear.
Now the big issue is getting the pistons out of the cylinder bores. Stuck very tight.
I got the cylinder base gasket joint unstuck and I get about 1/2" of up/down movement when I bump the bike in gear.
I'll soak the tops of the pistons a few more days in the heat.
If that doesn't work I suppose the solution is? cutting the top of the piston out by drilling around the circumference?
G
Grant
Guest
Can you blast the tops of the pistons with a hot air gun or something stronger?
Thermal shock between the alloy pistons and steel liners, plus lots of penetrating fluid beforehand, then using a wooden dowel on top of the piston with which to whack with a hammer.
I would try this long before drilling holes in things.
Thermal shock between the alloy pistons and steel liners, plus lots of penetrating fluid beforehand, then using a wooden dowel on top of the piston with which to whack with a hammer.
I would try this long before drilling holes in things.
Absolutely a 'controlled destruction' would be a last choice.
I was considering that the pistons/rings were the most expendable parts.
And that the cylinder bore and connecting rods were the parts to protect.
Anyone ever do piston top drilling to relieve the piston/cylinder wall bond?
I was considering that the pistons/rings were the most expendable parts.
And that the cylinder bore and connecting rods were the parts to protect.
Anyone ever do piston top drilling to relieve the piston/cylinder wall bond?
G
Grant
Guest
Most likely the liners will need to re-bored anyway as the rings will likely have rusted themselves to the liners causing pitting.
one of the bike mags here in the uk had an interesting suggestion this month for dealing with stuck pistons:
block of hardwood on the top of each piston & a puller plate over the studding then wind nuts down the studs and use the plate & wooden blocks to lift the barrels.
Of course this doesn't work if the studs run through the barrels into the crankcases
block of hardwood on the top of each piston & a puller plate over the studding then wind nuts down the studs and use the plate & wooden blocks to lift the barrels.
Of course this doesn't work if the studs run through the barrels into the crankcases
Laverda SF
Hero member
From the PIC's, kinda looks like your seats are shot let alone the guides. You have the perfect excuse to go to Larger Pro Flow Light Weight Valve. You may be able to save the guides if you use a larger Stem Dia and ream the guide but I suggest you put out the bucks for small dia SS/Silicon Bronze Guide and do your own porting - The question is - Do you want an 8000rpm SF?
Looks like you will have to polish the Cam Followers (Rocker Arm) and Cam Lobes. Hope the bronze bushing in the Cam Followers are descent and that Teflon Spool on the Cam Chain Tensioner looks worn out.
Just curious but when you inspect the Sump and Oil Filter Screen what do you find - Hope the Oil Pump Gears and block surface in the pump are not gouged?
Bye the Way: There a Trick when removing the Oil Pump Gear - It has to be aligned to get past the Oil Pump Gear Pin in order to pull the Gear and shaft out - Forget what the Clocking is but I'm sure someone has it.
Pay close attention to your shifter clocking - There are markings - Recognize or re-punch them.
Looks like you will have to polish the Cam Followers (Rocker Arm) and Cam Lobes. Hope the bronze bushing in the Cam Followers are descent and that Teflon Spool on the Cam Chain Tensioner looks worn out.
Just curious but when you inspect the Sump and Oil Filter Screen what do you find - Hope the Oil Pump Gears and block surface in the pump are not gouged?
Bye the Way: There a Trick when removing the Oil Pump Gear - It has to be aligned to get past the Oil Pump Gear Pin in order to pull the Gear and shaft out - Forget what the Clocking is but I'm sure someone has it.
Pay close attention to your shifter clocking - There are markings - Recognize or re-punch them.
Dellortoman
Hero member
- Location
- Tasmania, Australia
Forget "controlled destruction". It doesn't really achieve much to cave the piston crowns in. You'll be left with the part of the crown that you can't collapse (because of the gudgeon pin supports) and the piston skirt intact. It'll still be connected to the conrod and still stuck in the bore.
Better to follow advice already given - apply penetrating oil, heat, pressure, whacking with a wooden drift, etc ... They'll eventually give up the struggle.
It might be worth heating the cylinder block with a heat gun and try to cool the pistons with freeze spray or ice at the same time, then apply force to the pistons in whatever way you can. It's a bit tricky because both pistons have to move together.
Better to follow advice already given - apply penetrating oil, heat, pressure, whacking with a wooden drift, etc ... They'll eventually give up the struggle.
It might be worth heating the cylinder block with a heat gun and try to cool the pistons with freeze spray or ice at the same time, then apply force to the pistons in whatever way you can. It's a bit tricky because both pistons have to move together.
Laverda SF
Hero member
In all respect at 1st glance she appears to be a Sad Case - Not saying that SF can't be restored.
Dig into her further - Best of Luck.
Dig into her further - Best of Luck.
I took the top off one of the pistons in my triple after trying for about a month of soaking, heating, and hammering. I figured I had nothing to lose so I went with it. Got a little overzealous and drilled into the bore but it didn't matter as the liner was junk anyway.I ended up sawing through the skirt in three places to get the piston to release. Finally got the cyl. block off to find all three rods rusted solid to the crank.
I got all the bits I needed from Wolfgang and I didn't have to sell the children to pay for the parts!
My valve seats looked about like yours and they cleaned up with a couple hours of careful work with some Newway cutters.
I got all the bits I needed from Wolfgang and I didn't have to sell the children to pay for the parts!
My valve seats looked about like yours and they cleaned up with a couple hours of careful work with some Newway cutters.
phil37
Hero member
- Location
- Lincolnshire
I had a similar job a while back with a triple that had been ridden into a pond. I soaked the bores/pistons for ages to no avail. I then supported the cases on thick wood slats on my 30 ton press bed and managed to push enough to dislodge the pistons using a thick metal plate forcing down on spacers onto the two outer pistons - the 360? twin could be done the same way. - Regards - Phil
D
Davo
Guest
My apologies to show the result of long neglected storage of a good bike.
Mostly avoidable damage if oil had been applied regularly into the spark plug hole and the engine turned over.
Lots of work but finally got the cylinder free of the pistons.
No amount of oil soaking, heat/cold cycling, or beating would ever free up this mess.
I drilled the piston crown, then collapsed the top, then used a reciprocating saw to cut through the skirt on the front and rear.
Then used a heavy hammer and chisel to move the broken skirt material from the cylinder wall.
Luckily the crank turns OK but I think I hear rough main bearings.
Now the next step will be to get the broken chunks of piston and swarf out of the crankcase.
Stuck really bad!
Can you see the coil wire from the oil control rings?
Mostly avoidable damage if oil had been applied regularly into the spark plug hole and the engine turned over.
Lots of work but finally got the cylinder free of the pistons.
No amount of oil soaking, heat/cold cycling, or beating would ever free up this mess.
I drilled the piston crown, then collapsed the top, then used a reciprocating saw to cut through the skirt on the front and rear.
Then used a heavy hammer and chisel to move the broken skirt material from the cylinder wall.
Luckily the crank turns OK but I think I hear rough main bearings.
Now the next step will be to get the broken chunks of piston and swarf out of the crankcase.
Stuck really bad!
Can you see the coil wire from the oil control rings?
Dellortoman
Hero member
- Location
- Tasmania, Australia
The big-end bearings are knackered. You can tell because the rods are standing up. Normally they'd lie against the front of the crankcase openings.
I'd be tossing those rods in the bin too if I were you. Looks like there's a lot of rust pitting on them.
And get that engine out of the bike! You'll have to anyway to split the cases.
I'd be tossing those rods in the bin too if I were you. Looks like there's a lot of rust pitting on them.
And get that engine out of the bike! You'll have to anyway to split the cases.
CLEMTOG
Hero member
just like mt friend Cam above,
GET THAT ENGINE OUT OF THE BIKE (upper case used to replicate shouting)
i cant believe what you are trying to do with it still inplace and only two bolts and its on the floor, of course I hope that Cam and I are wrong and that you have already done just that, but by the position of the front wheel it doesnt seem likely, you cannot hope to achieve success without removing the motor.so your next step is..................
CLEM
GET THAT ENGINE OUT OF THE BIKE (upper case used to replicate shouting)
i cant believe what you are trying to do with it still inplace and only two bolts and its on the floor, of course I hope that Cam and I are wrong and that you have already done just that, but by the position of the front wheel it doesnt seem likely, you cannot hope to achieve success without removing the motor.so your next step is..................
CLEM
LaverdaIan
Hero member
Hey, Bob has a plan.. he's sure been going through it, and he's only new Clem old chum.. what better way to stabilise the whole thing while you hack into it with some brutal tools and not a little bravery.. 
, than a weighty lump like a Laverda rolling chassis don't you reckon.. Now that he knows FOR SURE that the motor's rooted I'm sure he's getting those 17mm spanners out as we speak.. right Bob.. 
8)
, than a weighty lump like a Laverda rolling chassis don't you reckon.. Now that he knows FOR SURE that the motor's rooted I'm sure he's getting those 17mm spanners out as we speak.. right Bob.. 8)
You are right of course.
I left the motor in the frame just so I could move it around easier.
If I had found the crankshaft rust frozen I would have rethought the whole idea of working on the bike.
The remaining mounting bolts are loosened and ready to come out.
I even found a thin wall 17mm box spanner at the local flea market for those nuts inside the swing arm area.
The next step will be to get the primary drive side apart.
I left the motor in the frame just so I could move it around easier.
If I had found the crankshaft rust frozen I would have rethought the whole idea of working on the bike.
The remaining mounting bolts are loosened and ready to come out.
I even found a thin wall 17mm box spanner at the local flea market for those nuts inside the swing arm area.
The next step will be to get the primary drive side apart.