Laverda 750 SFC 1974 replica

Thanks  i took cylinder head and cylinders to the machine shop yesterday (crank and engine block were already there) I saw crank and new connecting rods all polished up it needs to be pressed together and balanced. Than they have to bore cylinders to 900ccm repair combustion  chamber new valve guides bigger valves, Still don't know about cam 5 or 6c ?? after i talked with redax i was sure that i want 5c but the guy who does work on engine wants to put 6c cam i know that i will lose all bottom end power with this cam. I need to sleepover this :D

Problem with engine is that i don't have machines to do work on them. So i just hope that total price will be in normal range otherwise i'm screwed.

So now i'm waiting that parts will be finished and then i can start rebuilding the engine
 
ludiluka said:
6C cam i know that i will lose all bottom end power with this cam.
Click to expand...

Well ..  I would not be as drastic regarding the 6/C camshaft.
It does not transform the engine in a highly tuned two stroke race one..
Works great with the 2-1 open end exhaust though.

St?phane
 
  I use a 6/c cam in my 90? 750SF - I have had the rockers made a smaller radius so that takes out some of the overlap - pulls strongly from 1500rpm! -  As you're going to 900cc - you will have larger valves and this reduces the ratio of lift to valve size - so makes the 6/C cam "milder" - can't think of a better way to put it - Regards - Phil
 
i will use open 2-1 megaphone exhaust  about cam it is still a long way until i will need it. I'm sorting minor things on the frame.

Another thing about original sfc
seat bolts are they M8 or M6 ? i can't really tell from pictures ?
Rivets for the seat leather what is diameter of the head? Are they modern style rivets or something else? Any good photo of original rivet?
I don't have ignition lock and i will run bike without switches on handlebar. So i'm thinking about car style ignition lock so first position contact second position starter?? or using original lock + starter button (i don't have idea where to get small starter button that is water proof and where to mount it.)
I also need tomasseli throttle mine is scratched but they are bloody expensive :(
oh and brake lines and after that only thing missing is the engine.
 
So i started thinking more about engine now :D Where can i save rotating mass?

I will run 2 single chains if my thinking is correct you install this chains on inner and outer sprocket so middle sprocket is empty and can be turn away? on crankshaft sprocket and on clutch sprocket.
Is it worth taking clutch apart to change rubbers inside of the clutch ? any experience are old rubbers usually good or bad ? How about drilling clutch basket ? i think that i saw picture somewhere but i cant find it anymore.
Drilling oil pump sprocket
Same with starter clutch is there any way  to lighten it ?
Drilling front and rear sprocket.

I'm open to any suggestions how and were to get rid of excess rotating mass.
 
You can turn down the middle row of teeth on engine and clutch sprockets if running 2 single chains. Better still if your budget allows, run a duplex chain from Andy Chain on this forum somewhere?
You can drill oil pump/ignition sprocket.
You can drill the clutch, both Phil Todd and Redax have posted photos.
Old clutch rubbers are usualy bad. See if you can detect mouvement in the clutch sprocket by hand. If so, rubbers definitely dead.
Paul
 
+1
Paul Marx said:
Better still if your budget allows, run a duplex chain from Andy Chain on this forum somewhere? 
Click to expand...

please send message to Andy and get advice.  please !!
http://www.laverdaforum.com/forum/index.php?action=profile;u=330
cheers,  Mark
 
Great i know that Andy is selling chains but i was thinking that duplex or triplex isn't available anymore.
Ok so i will use duplex and turn down outside sprocket even better :D
 
You can drill the clutch, both Phil Todd and Redax have posted photos.
Click to expand...

Here's some shots:-  transmission ones are for a triple - but same idea for 750 - Regards - Phil
 

Attachments

  • smc - mod.jpg
    smc - mod.jpg
    84 KB · Views: 36
  • clutch,jpg001.jpg
    clutch,jpg001.jpg
    101.2 KB · Views: 51
  • clutch,jpg003.jpg
    clutch,jpg003.jpg
    108.6 KB · Views: 44
  • clutch,jpg004.jpg
    clutch,jpg004.jpg
    105.3 KB · Views: 42
One more thing :D

bronze bush that should be inside that hole should it be tight fit between bush and clutch basket i assume that it should be ? Because mine just fell out without any pressure. What is the best material for new bush ?

dsc02381.jpg

dsc02391.jpg
 
So is something like this ok? i dont want to invent hot water again :D

dsc02441.jpg

dsc02451.jpg

dsc02461.jpg

dsc02471.jpg


About sprocket what is better 2 holes
dsc02481.jpg


or can i take the whole thing out?
dsc02491.jpg


Can i drill this disc?
dsc02501.jpg
 
Yes, it's Ok. I have no personnal experience of drilling or lightening.
You can fit an oversize bronze bush. According to Piet, you can convert to triple type needle bearings. I haven't researched, but maybe there exist needle roller bearings close to the original diameter.
Paul
 
You must log in or register to reply here.
Back
Top