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Has anyone any ideas as to why my clutch has suddenly started slipping from 8000rpm the needle surges without any power increase and then it catches up!

Background, bike has done 26k, not sure if the clutch has been changed (only just bought the bike) i changed the oil a week ago, after much reading I went for 15-50 so that shouldn't ave caused it!, Ive not bled the cluch yet, so will try that tomorrow.

Is putting a new clutch in a tricky job? I have only basic mechanic skills!

cheers
Oli

Olig7475 wrote: i changed the oil a week ago

I think that is probably the significant part... what oil did you put in - was it semi synthetic or full synthetic? Also was it a motorcycle-specific oil or was it a general automotive type oil?

I believe that earlier Falcos are susceptible to clutch slip if fully synthetic oil is used. The recommendation is to use a semi-synthetic 15W50 oil formulated for bikes (JSMA specification). Or so I believe.

am also willing to bet it is full synth oil in there

semi synth only for any falco upto 2003 ... ish

Wot he said.

Just do a search on cluth slip and you'll find a plethora of threads and opinions on the ups and downs of fully synth and semi synth oils.

If you can find out what oil the previous owner used changing back to that will probably solve the problem.

semi synth, bike oil!!!!!

Also check out Thumper's post from today in the following thread (not Thumper's post that started the thread)

https://www.ridersite.com/viewtopic.php?t=4015

Olig7475 wrote:semi synth, bike oil!!!!!

Well you've clearly done the right thing, but the timing of the clutch slip is highly coincidental. What make and spec of oil did you use?

hmmm

clutch fluid volume ok?

this sounds wierd - unless the clutch is fried....

yeah a bit strange really, everything works fine for 5-10mins and then it starts to slip!! I used this oil

http://www.bitzforbikes.co.uk/-ref-13471-149.html

Clutch fluid level is good, I'm going to try bleeding it see if that helps.

Bleeding is worth a try, but I'd be surprised if that makes a difference, unless you've made any other changes to the bike recently that might have affected the clutch? The oil is the most obvious one, but if it's semi-synth, that shouldn't be the problem. If you get no joy, I'd suggest swapping the oil out again before swapping the clutch out, try a different brand of oil just in case there's an additive that's causing the clutch slip.

I'd be tempted to swap the oil . I'm not too up to speed on oil ratings but I note the "Hi-Rev" oil meets API-SM standard. Aprilia state the oil must meet API-SG standard

Now of course "SM" might be a higher standard than "SG" I don't know, but if it isn't that could be contributing to the slip problem (I'm sure someone will dive in here with the right info)

Even if the clutch is knackered it's easy to change the plates, you don't even need to drain the oil

F9

When you changed the oil.... did you notice any fibrous material indicating possible wear to the clutch plates? But i guess you would have felt something before the oil change if worn plates were the cause.

Hope you get it sorted mate.

i've run mine since day one with putaline 15/50 which as got anti slip properties and never had a problem, if yours is just a standard 15/50 i think thats going to be your problem.either go for the putaline or put a 10/40 semi synt in, if it still slips get the spanners out.
ian.

Right, gonna change out the oil, was never sure about that 'Hi Rev' stuff but it was all I could find at short notice. I see that DT's do the Putoline 15-50 semi so I'll get some ordered and report back.

Thanks for all the advice guy's, I'd be f****d without it!

If the clutch still slips after the oil change, you can take the plates out and roughen the steel plates on some coarse emery cloth. So long as the friction plates are ok, just pop them back in and the clutch slip will be gone. Did mine and it's done nearly 10k since. The whole job takes less than an hour and, best of all, costs nothing