Not an exact match but a bit similar.I tried metal spraying to reclain the 1st gear clutch hub on my Husqvarna Automatic.Its has a centrifugal clutch and drive system that works a bit like a drum brake,the shoes are made from Brass and run in a steel drum that had warn oversized.All it ended up doing was picking up on the brass shoes and tearing even more out of the drum.All I wanted was a smooth surface inside the drum with the right dimension to transmit the drive,when they are undersized the springs work outside there stretch limit and brake,suprise suprise it is like a Laverda sprag.Big differance is the Husky bit works all the time and much much harder and gets a shit load HOTTER
Free wheel gear
- Thread starter ITALOSOUND
- Start date
Dellortoman
Hero member
- Location
- Tasmania, Australia
Is that a Husqvarna chainsaw Vince? I thought they only used automatic drum clutches on scooters and chainsaws.
Seems like a crap system to put on a real motorbike.
Seems like a crap system to put on a real motorbike.
They were originally designed to be used by the Swedish Military,between 1982 and 1985 they won a shed load of endro medals all over the world.Mine is a 420cc 2 stoke 4 speed fully automatic.Its blindingly fast in the tight stuff,they go better accelerating at maximum.More revs= less slip=less heat buildup.Only downside is ZERO engine braking when the throttle is closed,and thats not 2 stoke engine braking,its like pulling in a standard clutch,scary on big downhills with the standard drum brakes.Mine has a Kawasaki disc brake frontend.My other dirtbike is a
2005 Husky 4 stroke 250,I liked the older auto so much my I fitted a Recluse centrifugal clutch to the later bike.
2005 Husky 4 stroke 250,I liked the older auto so much my I fitted a Recluse centrifugal clutch to the later bike.
SimonR501 said:
Should be Simon, but rarely are... especially the ND variant. The rollers have such a small contact area, dents can hardly be avoided.
Totally different operating principle to an automatic drum clutch. This relies on friction between centrifugally operated shoes and the drum. The sprag clutch wedges rollers between 2 rotating bodies via a set of ramps, no centrifugal force involved.
piet
we are same as Keith, have a box full of worn ones, nothing wrong with them except for the area where the rollers hit
I considered the Eutectic products as I have used them myself years ago, even went and did their 1 day course on correct applications
is a great product, especially for repairing worn rotary assemblies where there is a requirement for say seal contact but I don't really believe it would survive the loads imparted on to it when used on a Laverda sprag clutch which would be a combination of impact, crushing and shearing
was interesting to read Piet's experience in trying to work out a suitable repair and I totally agree with him, there are some very high loads happening in there when you hit the starter button
had planned to sleeve them but that looks like it is a non starter now
one just needs to look at the damage done to a Howdie sprag clutch after it has been installed in a Laverda engine for awhile, pretty well destroys them to the point where he refuses to build them anymore
I considered the Eutectic products as I have used them myself years ago, even went and did their 1 day course on correct applications
is a great product, especially for repairing worn rotary assemblies where there is a requirement for say seal contact but I don't really believe it would survive the loads imparted on to it when used on a Laverda sprag clutch which would be a combination of impact, crushing and shearing
was interesting to read Piet's experience in trying to work out a suitable repair and I totally agree with him, there are some very high loads happening in there when you hit the starter button
had planned to sleeve them but that looks like it is a non starter now
one just needs to look at the damage done to a Howdie sprag clutch after it has been installed in a Laverda engine for awhile, pretty well destroys them to the point where he refuses to build them anymore
Xav,
Bite the bullet and buy a new one, saves a lot of grief and despair, not to mention the precious time lost tearing the sucker down yet again!
No use replacing only the wheel if the rest of the clutch is just as knackered, you'll be replacing the wheel in the very near futere once again, wrongly blaming the supplier/manufacturer for lousy material quality.
About the only sure remedy is a handful of new components, correctly assembled. Then you need to check if your ignition and battery are up to scratch. A weak battery giving a wrongly timed spark at start-up will fuck the sprag quicker than you might imagine.
piet
Bite the bullet and buy a new one, saves a lot of grief and despair, not to mention the precious time lost tearing the sucker down yet again!
No use replacing only the wheel if the rest of the clutch is just as knackered, you'll be replacing the wheel in the very near futere once again, wrongly blaming the supplier/manufacturer for lousy material quality.
About the only sure remedy is a handful of new components, correctly assembled. Then you need to check if your ignition and battery are up to scratch. A weak battery giving a wrongly timed spark at start-up will fuck the sprag quicker than you might imagine.
piet
sfcpiet said:Dellortoman said:
Don't believe in turning back evolution...
The ring seemed to have "spreaded" and was quite loose on the boss. It was made from a needlebearing inner race and shrunk on with a mighty interference fit, too much to simply press on. Was worried it might interfere with the inner bearing, but that was OK.
piet
What about this ?
Perhaps that with a good shot of calves (mollet)
