SF sprag clutch, ignorance is bliss

Lyndoneil

Lyndoneil

Full member
Location
Towcester uk
Sorting throigh the potential problems on this recently purchased SF2, thought I would check out the starter freewheel clutch, as occasionally it made an unpleasant scrounging sound on the starter button, not always, but enough.
Almost wish I hadn't,  but it would have been worse issues stored up for the near future.
Having removed the sprag clutch, only 3 of the rollers were actually doing anything, so only 3 springs  and only 1 pin had not split into 2 pieces one way or another, but unfortunately  2 of the pins are seized deep in the holes and do not want to come out, and although I have not drilled  the rivets out and removed the back plate, it appears the inner ring that holds all the pins, springs etc is fractured.
So I have to either replace the whole lot or parts,
How would I rivet it back together, the sizes look awkward?
Anyone have a reasonable used one?
All the bits I'm having to replace are f?????g expensive,  either that or everything with Laverda's
Is expensive anyway.
 
Kinda makes you wish a Breganzie didn't come with a kick starter; but, who needs a kick starter when you have a Bar Maid shoving you off to work in the morning. Something your wife will never understand  ;o)
 
I'm sure Lyndonell found that very useful and informative, Ron  ::) . Barmaids ...  :o

Ron can actually explain how to replace the rivets with countersunk screws when refitting. I believe the insert is replaceable, but also believe, yes, it is expensive! It's a complicated machined part.  You're probably just going to have to bite the bullet, and once fixed, take Piet's advice and service once a year - not a tricky job.
 
Not too difficult to properly rivet the sucker together again.  Screws, weld and similar bodges are simply not necessary.

It can prove to be difficult to impossible to remove a jammed plunger, removing the insert is often the only way to go.  The plungers can then be poked out from the outside of the insert.

The inner ramp thingy is expensive, and the only alternative is a new one if busted.  I often find it broken into 2 or 3 bits, which really does render it scrap.  If it is only cracked once, and still hanging together, it MAY still be quite servicable, depends on the fit in the housing.  Thankfully, they are now available in a better quality than the originals.  Rollers, springs, plungers, cover plate and rivets all in stock.

The insert will cause issues once it is worn to the point that the rollers no longer jam the driven sprocket adequately.  Flat/low battery charge, incorrect ignition timing (often a consequence of the former in conjunction with electronic ignition systems) both contribute to premature failure of the starter clutch, this applies to all Laverdas, not only the twins.  Backfiring upon starting wreaks havoc on the springs and plungers.

A regular service with new springs and a couple of drops of oil go a long way to maintaining reliability.

piet
 
This is how I extracted a couple of 'permanently' stuck pins. Once done I can easily remove all of them without the need for mistreatment. As mentioned previously, getting the drill aligned is tricky - and it requires a mill drill to create a flat for the drill bit to centre on. I LOVE my lathe  :D

 

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The inner freewheel ring looks like its fractured as well as having 2 pins jammed in, was going to order the parts  and fix it myself, but after ringing Roger at OCT I decided to put in in a parcel and sent it to them to strip and rebuild,  I know it's a bit of a cop out, but I was going to have to take it somewhere to drill the rivets out as I haven't a pillar drill, then didn't know if I should order the adjustable square spacers, wether to re-rivet, weld or bolt the thing back together, without getting it too tight,  too loose and then possible destroying the starter or having to start again.
I know 'Coward!'
A quick way of parting with a fair amount of money on something that looks really insignificant
 
Lyndoneil said:
The inner freewheel ring looks like its fractured as well as having 2 pins jammed in, was going to order the parts  and fix it myself, but after ringing Roger at OCT I decided to put in in a parcel and sent it to them to strip and rebuild,  I know it's a bit of a cop out, but I was going to have to take it somewhere to drill the rivets out as I haven't a pillar drill, then didn't know if I should order the adjustable square spacers, wether to re-rivet, weld or bolt the thing back together, without getting it too tight,  too loose and then possible destroying the starter or having to start again.
I know 'Coward!'
A quick way of parting with a fair amount of money on something that looks really insignificant
Click to expand...

I'll let you know how it goes... :D

What do you mean by "adjustable square spacers"?

piet
 
It?s never a cop-out to use a proper expert. They will do the job better and quicker, using the right tools. You might even get a warranty, or at least some advice about what to do next time. As an expert myself in another field, I?ve seen lots of people make easy jobs very hard by trying to do it themselves.

And if they make a mistake they?ll know how to fix it before anyone finds out  :LOL:
 
Hi Piet, I dont know!  Dare I say, 3-31 on the laverda Parardies parts diagram, (adjuster square freewheel.) My own parts book only shows the freewheel clutch as a complete part other than the roller, pins and springs. If I knew what I was on about, I wouldn't need people that have vastly better knowledge than me.
I've only had a SF for about a month, and gaining an extremely rapid knowledge about what can go wrong with them if they have had missed maintenance and how astonishingly  expensive the most insignificant part can end up costing. But it will  be a great incentive  to make sure maintenance is not skipped in future and  hopefully eventually I will either stop removing bits because they dont sound quite right, or I will have fixed all the problems that the last owner decided they were happy to live with.
 
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