Possibly a stupid question.

padlock

padlock

Hero member
Location
bedford Uk
Hi All. Ok, Very shortly i'm about to undertake a complete strip and rebuild of my engine. I have never done this before!!!! How difficult is it? I'm no idiot with spanners but by the same token i'm no whizz mechanic. Should i do this? Can't afford to give it to keith with a massive wedge of folding. What are the most important things to look out for etc. Thanks
            Mark
 
On the Richter scale it's about a 4.5, on the Kelvin about 234.7. :D
 
I was umming and ahhhing the very same last year. In the end I figured out that at the very best I could get the engine back together and have it run reasonably well (assuming I could find someone in WA to rebuild the crank properly) or I could send it away to someone who knew what they were doing and get an excellent piece of kit back. As it turned out there was no-one in WA who had the gear to do the crank so either the crank or the whole donk was going to go away. Opted for Red ( the poor bugger) for the engine, the rest I can and will do myself. I'm sure it will end up being the cheapest option anyway as I would probably have f&%ked the engine anyway.
 
Hi , when it comes to engine work it really is a matter of you "pay for what you get and you gets what you pay for" !!.so i would have to say if not confident to handle the job "DONT" do it , spend the wedge and enjoy.. ;)  ;)           
 
Padlock, as we don't know your competence level with engines and Laverda engines in particular it's impossible to answer. You say you are no idiot with spanners, but is that assembling an IKEA table or some level of engine work before?

Laverdas are not complicated to work on, but they do assume a certain level of ability.
There's one thing about opening and fitting bits and pieces, but can you do stuff like changing bearings, or shimming valve clearances?
And these are the basics.

It's a lot of expensive motor to go pop to start your learning curve with.

Your call.
 
I'm quite happy to do the straightforward assembly myself but anything more than that ( i.e. degreeing in the cam timing) I would not be confident about without being shown how to do it first. I'm sure when I first started on Laverdas many moons ago I broke more than I fixed but eventually I learned my limits. I would go for it myself Mark. Any specialist work can be done by....specialists.
Just dont use a chainsaw  :D Pat
 
I am an idiot but have watched over the shoulder of some of the best in OZ on Laverdas,its a simple design BUT there are a few Laverda only bits and some traps for first timers.Even experienced motor blokes who haven't seen inside a Laverda could have a problem and there are more ways than one to skin a cat.When I say problem I don't mean catastrophic,I mean not 100% tidy.The more you do on them the more you learn.BTW thats excluding cranks,now thats a steep learning curve
 
Righto, To Throw a little bit more light on the matter. Head will go to keith, complete, for all work, ditto the crank. In the past i have always been happy to throw spanners at whatever car/truck i've owned, wheel bearings, head gaskets, clutches, drive shafts etc. never really worked on bike engines more than maintenance. So the internal workings of an engine is somewhere i've not really gone before. But 2 important points; 1, i really want to have some input in building the engine and,2, i wish to learn. another but is i don't want it all to go tits up. After reading some of the replies i'm beginning to think that maybe i should just save harder and swell mr keiths bank balance a bit more. maybe i'll just flip a coin! Cheers
             Mark
 
hello Mark (padlock)
I would say here the main and first thing is ......do you have facilities?.I have done more of this over the last 35 years than I can bring back to mind.You dont realy need a hydraulic work ramp to get the motor in and out of the chassis, but boy oh boy does it make life easy, especially when setting up the rebuilt motor.Loosen the crankshaft nut and alternator nut, before you remove the motor from the chassis. What you will for sure need, is a good work bench.When I am rebuilding triple motors I use  what we call "the engine bench" this is  2 metres long and 600mm wide.There is just enough room to break the unit down and lay it all out, then there is "the work bench" which is a similar size, and at 90 degrees to the other,A workmate or the top of a tea chest would be useless. this is where individual components are worked on, and of course in a nice warm garge with 8 foot double strip lights above the benches,All the time we save plastic food trays (the type you get your pork chops in) to place components in, gearbox, clutch, primary drive/chains , starter freewheel, all kept in little sub assemblies.Wherever possible once an item is removed,eg primary cover, put the bolts back in their threads, use cable ties to "keep" small easilly lost parts, such as main bearing retaining rings.When you unbolt the cams, use lockwire to retain the bearings (on the cams).Use an egg box (six compartments) to place the tappets and shims in a marked order, I draw the chain position on the box and also write "IN and EX" plus 1,2,3. (courtesy Toddy circa 1974)

You will need some special tools, these can be begged or borrowed,If you are in ILOC (and UK resident) then you can borrow almost anything., via the clubs tool loan scheme.A crankshaft locking tool and an alternator extractor are essential, less so but still desirable is a box spanner for the bearing nut ,under the alternator, plus other sundry items.

we all want to help you, and if diesel Davies can do it,in his garage with no natural light and only one 40 watt bulb, so can you !!
CLEM

 
padlock said:
Hi All. Ok, Very shortly i'm about to undertake a complete strip and rebuild of my engine. I have never done this before!!!! How difficult is it? I'm no idiot with spanners but by the same token i'm no whizz mechanic. Should i do this? Can't afford to give it to keith with a massive wedge of folding. What are the most important things to look out for etc. Thanks
            Mark
Click to expand...

Hi Mark

how many miles/kms on the engine? Why are you planning to strip it? Symptoms? what is the driving force to do a complete bare crank rebuild?

A Laverda crank should be good for at least 150,000 kms, probably more, as long as the oil was changed regularly. If the engine has less than say 150,000 kms on it, barring any obvious symptoms, I would be betting all the engine may need is a top end refresh. The piston rings and the valve guides and seats will wear more quickly than the crank.

so, for diagnostics, have you done a compression test, both dry and wet? What are the readings? Have you done a leak down test? What was the result? When was the cam chain changed last? What are the shim sizes presently being used in the valve train (shim thickness will typically give a good indication as to how much wear the head has undergone in use, shims in the range of say 2.5 and above will be a goood indicator the head is still well within serviceable range, for example).

If all the engine needs is a top end refresh, that is well within most home mechanics abilities as to dis assembly and re assembly. The specialty work is having the head checked for valve condition, valve seats, valve guides, and valve springs. Takes specialist knowledge and proper machine tools to either replace or reline the valve guides. So, send the head out, no big deal.

For the pistons/rings/bores, easy enough for you to remove the rings from the pistons, stick the rings back into the bores, and measure ring end gap. That will tell you where the rings are as to wear at no cost. Then you can take the pistons/bores to a specialist to check bore wear, ovalness, piston wear, piston to bore clearance. You may just need a quick bore homne and fresh rings, or you may need the bore liners honed, next size up pistons, fresh rings.

you don't necessarily need to spend a fortumnne on the engine, you can do most of this yourself with basic hand tools, just a few specialty tools which are readily obtainable. Best of all worlds would be a helpful buddy ewwho may have done this before, is anyone near to you who could give you an experienced helping hand? I do that all the time local to me.

I don't know what your bike is. A 1200 triple is much easier to get the motor out of by yourself than a 180. For that matter, with either a 180 or 120 it is easy enough to pull the head/cylinders/pistons with the engine still in the frame.

Finally, the only way to learn is by doing. These are simple basic engines, and there is enough expertise here on this list to answer ANY question that you may have. I say go for it yourself, using expert technical help for the head and bores as required....... but I am still curious for answers to my questions in the first couple of paragraphs of this post....

Paul LeClair 
 
there are no stupid questions here mark
you are going in the right direction sending head and crank to keith
these are components best left to specialists

disassembly is pretty straightforward, don't miss the nut under the starter

we can walk you through the whole process

you will need a deep 36 and an alt puller for a series 1 180
for series II disregard this paragraph
my 36 is made from a std socket as the conventional deep one wasn't deep enough
the socket end is faced flat as the nut is thin
then parted in two on a lathe but can be sawn, too
find a similar OD size bit of pipe cut ends off square
weld pipe section into socket halves minding to keep it true as you can
and you have an appropriately deep socket
the nut is LH thread

primary cover takes a bit of patience and a hide headed mallet to slowly work it off.
resist prying as the alloy is soft

mallet will also be useful for separating well stuck case halves
try to bring it up square else it binds on the studs
double check all nuts have been removed
make note of which studs use copper sealing washers

a piston pin puller would be wise to avoid possible damage

needn't worry about taking primary gear off crank
the mainshaft with clutch can be lifted out of lower case and rotated forward to remove primary chain
have keith renew bearing race for primary cover when doing the crank
consider having him lighten clutch components and converting to duplex chain from andy
he can machine the extra teeth off the gears reducing weight, too

clutch can be disassembled from mainshaft after removal, no problem

once apart you'll want to do a general cleaning of components to measure wear
things to look at will be pistons; skirt size ring and land dimensions
bore condition; checking diameter in thrust direction and at 90 degrees from same,
look for taper and oval wear in the bore measurements
frequently there is a lot of wear where the top ring stops in the bore
these dimension checks will determine if overbore is required
or if sleeve needs to be rotated or simply needs rings
we can get more detailed when you get to this point

gearbox can be dropped back in place to check end play between gears
gear teeth need to be examined for condition and wear pattern
4th gear will likely need to be rebushed
5th gear requires examination of sprocket splines, if ok it likely could use rebushing as well
you'll need pullers to get bearings off gearbox shafts
earlier ones have peened ends to retain inner race on layshaft

that's the hard stuff
there is more but we can go over individual bits in turn
these can be done, bagged and set aside for later assembly

for reassembly cleanliness is a virtue that will reward you with longevity
there are a lot of small procedures for prepping components prior to reassembly
but you want to get all the little stuff sorted first

do let us know the model as there are some detail differences

cheers,
scott
 
actually,Keith's hourly rate is exceptional value! he also spots stuff that you wont. I am glad I initially took the thing right down to the gears some 8 years ago now(at Clem's insistence) and learned a lot in the process. I had the misfortune of finding all sorts, including shot mains, worn pistons etc. Its great to do work yourself, and on mine I have most recently enjoyed making my own ring compressors and lowering the barrels. But Keith did all the head work and some great stuff with the primary drive chain (duplex merc jobbie) aligning properly, and some subtle working of the eccentric gear selector screw (has never changed better) as well as fitting the Red/Sachse ignition. If you are contemplating pistons/rebore, and a crank job, you'll be spending a fair few bob anyway. I know you wanna do it, but although it wont be cheap, if you possibly can afford/justify it, I would get it to Keith. I would also get him(did actually) to look at the carbs, and (I know, I know, it really will break the bank) fit a new ignition. And best not tell the wife..I certainly didnt! The rising prices mean its all reasonable expense in the scheme of things? ;)
Nick7
 
Blimey, I love this place,
Clem, Yes i have the facilities and the tools but filled with trepidation about under taking such a task,
Tim, I live in bedfordshire in a wee village called `sharnbrook.
Paul, Several reasons as to why I'm doing a complete strip and rebuild. First off. My bike is a mirage that i bought as a pile of bits but engine in one lump.
I don,t think it had been stored very well. My aim is to build a totally none standard, fast as i can make it(as far as my pockets will allow) Laverda.
The frame is at Keith's at the moment headstock has been braced, swing arm pivot braced and increased to 16mm, Nigel hill swingarm fitted along with period dymags. I was going to leave the engine alone till i had sorted everything else chassis wise. But, When i had a quick look under the cam cover and primary drive cover there was quite a lot of surface rust evident. The engine had no oil in it and also you can see a wee bit of rust on the valve stems. So I'm guessing the bottom end is in a similar state. Also I'm after 100 break at the rear wheel which will mean serious head work,Carrillo rods, Hi comp pistons, uprated oil pump Etc. In other words... Sh*t loads of money.So as they say... In for a penny in for thousads of pounds. Think the entire build will cost me in the region of ?10000. Thank you all very much for your replies and encouragement. Flipped a coin and it said i,m doing the work. Millions of questions to follow soon, Cheers. Mark
Ps. My aim is to have her on the road by April next year. Wish i was rich!!!!
 
You are! Think of how much fun you'll have ....that's real wealth, not money.
 
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