Silly Question of the day - have mercy on the simpleton

[Tonto]

Guys, any sane advice appreciated
I am mechanically retarded - hence the dumb question.

My 900A4 has just developed an intermittent fault: it feels like clutch slip, but only when excelerating hard between 5-6000 RPM, and nowhere else in the rev range. Also, she does not do it all the time: less so when fully warmed up with about 20+ miles on her.

Any obvious or potential gremlins come to mind ?

Cheers Tim

[Z1parR]

5 - 6000 revs , have you no regard for the planet with all your emissions

[zed1015]

It is clutch slip unless it's wheelspin.
Nothing else can really replicate that situation without being acompanied by other horrible noises.

[z1000puddin]

Could be your oil.
When did you last change the oil ?
Oil viscosity will break down over time, this could be why it only does it after getting warm.

stu

[tlc]

Check the adjuster at the pushrod.

Lossen cable fully, undo locknut and tighten screw until you feel it hit the pushrod. Back off at least quarter turn and do up locknut. Adjust cable and test drive

[PAULJAC47]

Not using car oil by any chance?

[DogsbolloxofZ1B]

As all have said. Any broken clutch springs?

[Tonto]

Thanks for the responses guys.
The bike had a full rebuild 1000 miles ago, and I changed the oil only 300 miles ago - bog standard Castrol 10-40 mineral.

Think I will go and stare at it some more tomorrow before having a good fettle.
Cheers Tim

[KeithZ1R]

Doesnt clutch slip show up on the kick start as a slight slipage when booting it over ? If mine have been stood a while i always bolt on a kickstart to free the plates off saves that horrendous crunch when you put it in gear

[andyb1962]

If mine will be stood a while i sometimes tie a tywrap around the clutch lever 12 hours before i ride it. This also frees off the plates and helps eliminate that painful crunch when selecting first on a cold engine.
I would check the clutch adjustment first.

[kev edwards]

Also check the front sprocket nut has not come undone, the sprocket can slide on and off the spline giving the feeling of clutch slip, how do i know this you may ask, well it happened on one of mine.

[PAULJAC47]

Thanks for the responses guys.
The bike had a full rebuild 1000 miles ago, and I changed the oil only 300 miles ago - bog standard Castrol 10-40 mineral.

Think I will go and stare at it some more tomorrow before having a good fettle.
Cheers Tim

Castrol car oil???? i have had issues with car oils causing clutches to slip, though some swear by it,modern car oils are not suitable for bike clutches!!did the clutch slip b4 the oil change?

[Tonto]

Thanks guys all for the pointers - will have a good look over the weekend, use these as a check sheet and see if I can crack it.
Paul - re the Castrol: yes I am using same oil as before, but the slipping only started about a week ago.
Bit of a bugger really as it looks like a wall to wall Sun-fest this weekend: heresy I know, but I'll probably have to use the Kettle for my 2 wheel fix.

Cheers Tim

[KeithZ1R]

Nowt wrong with riding a kettle mate lovely things

[Garn 1]

Tonto, agree with Kev Edwards (about post #11 above). I've heard of this sprocket running off and back on, shearing the tabs on the lock washer.
Another item to look at is the clutch release mechanism.

Had a strange problem the other day, adjusting the clutch. We all know there should be some play at the lever to ensure we are not unwittingly engaging the clutch, that is, putting pressure on the push rod unnecessarily. I found I had about 10mm of play at the lever and could not adjust it out.

The problem was in the small rivet that holds the swivel at the end of the actuating arm...


That rivet with the 8mm head has a shaft about 6.5 mm dia and had worn about half way thru. I checked all the others I have and found excessive wear in all of them. A job for the lathe.... Drilled out the hole in arm to 7mm. I think it was case hardened and turned up a new rivet. Never bothered to check these before!

Picture below shows the wear on the 6.5mm section of the rivet in the clutch release mechanism.... I will in future check this rivet for excessive play.
Gee! Another forty years I would be in big trouble!
.
RegardZ.