Slipping Clutch @ Snetterton

[Dal]

I think I may have found the reason my clutch was slipping. :grin2

Starting at the begining. The clutch was slipping at high RPM on the front and back straight but only in the top gears. ;)

Anyway I had a look today and the springs are well within tolerence as are the plates. Cable adjustment was / is good. :confused:

So it left me a little confussed but I think the culprit may well be the oil I was using. Although the correct weight (10W40 semi synthetic) it's a Castrol Oil looking a bit closer it's a Car Oil (Castrol GTX Magnetec) which I think has got an additive that makes it extra slippy (is that a real word?) and I think it's this that was making the clutch slip. :grin2

What do you lot think?

[rembrandt]

:laugh1:laugh1:laugh1 think you found your problem M8 car oil has got additives which bike clutches dont like :grin2:grin2:grin2

[Gixxer-TeZ]

Might be a fully synthetic. You may be a part or non-synthectic oil. Never had to change the oil on my B1H so couldn't tell you the correct oil.

[Lateshift]

10w40 semi-synthetic is what you want, never had any clutch slip when using that even when its been put in the RSV (and Aprilia recommend a 15w50 full synthetic that gives nothing but problems :D ).

But yes, most car oils have additives that are specifically for cars and not bike clutches :)

If you are going to use Castrol then the 10w40 GP stuff works well, as does Silkolene Comp 4 10w40 and so does Morris Supersport 4 (which according to Perilous is what Dynotech use on all their tuned engines specifically to avoid clutch slip ;) ).

[Perilous]

Yup, Semi synthetic only in a ZXR 400 and just change it regularly.
Morris gives no clutch slip whatsover with 81hp, 2000 extra revs and countless race starts and all the main bearings big ends etc last two seasons which I can assure you is very good for a highly tuned glorified mower engine running 14.7 > 1 compression.:)



Also only use standard friction plates. The EBC ones are cr4p in the 400.

[Dal]

Thanks guys for confirming my suspicions :grin2

Oh and where do I get the morris stuff (I would normally steer well clear of anything called Morris :laugh1)

[Perilous]

Thanks guys for confirming my suspicions :grin2

Oh and where do I get the morris stuff (I would normally steer well clear of anything called Morris :laugh1)

I either pick mine up when i'm at Dynotech or get it at Chris Pryke's in Heybridge but Mick knows a shop nearer to you that does it.

To be honest any decent motorcycle semi synthetic will probably be Ok I just use Morris because we know it doesn't make the clutch slip so it eliminates the oil out of the equation if there is a problem.

At the end of the day we're pushing 25 more HP * and an extra 2000 revs through the clutch than a standard bike so ours tend to work a bit harder.


(Measured against a standard ZXR on the same dyno on the same day. )

[Lateshift]

Soper's by sheer luck stock the range of Morris oils :)

[Dal]

Soper's by sheer luck stock the range of Morris oils :)

Ok so next stupid arse question :grin2 Where's Sopers? :confused: :D

[Lateshift]

SACRILAGE!!

BURN HIM BURN HIM!! :D

Errr Sopers is on London road on the way into Saaaarfend (Leigh on Sea), next door to Just Bikes, there isnt a lot that Sopers cant get for you including spare parts too :)

http://www.multimap.com/maps/?title=Julian%20Soper&hloc=GB|SS9%202AB

[Dal]

SIR! THANK YOU, SIR !!!!! :grin2

[Mi5ter E]

I think I may have found the reason my clutch was slipping. :grin2

Starting at the begining. The clutch was slipping at high RPM on the front and back straight but only in the top gears. ;)

Anyway I had a look today and the springs are well within tolerence as are the plates. Cable adjustment was / is good. :confused:

So it left me a little confussed but I think the culprit may well be the oil I was using. Although the correct weight (10W40 semi synthetic) it's a Castrol Oil looking a bit closer it's a Car Oil (Castrol GTX Magnetec) which I think has got an additive that makes it extra slippy (is that a real word?) and I think it's this that was making the clutch slip. :grin2

What do you lot think?

i had a similar thing when i changed the oil in my 1200 bandit so changed it again all sorted

[Moto.]

So it left me a little confussed but I think the culprit may well be the oil I was using. Although the correct weight (10W40 semi synthetic) it's a Castrol Oil looking a bit closer it's a Car Oil (Castrol GTX Magnetec) which I think has got an additive that makes it extra slippy (is that a real word?) and I think it's this that was making the clutch slip.

I'd say that's pretty likely. I had a similar issue with my race bike (2k6 GSX-R1k). The torque that the big bikes make plus the slippy slippy of the Synthetic...doesn't seem to work together so well. I tried full and semi synthetic. Then I went back to mineral (Motul 3000). The oil gets changed every day the bike is run so it being mineral, Syn, or Semi isn't an issue.

[Morris]

Oh and where do I get the morris stuff (I would normally steer well clear of anything called Morris :laugh1)

:O What did we ever do to you? :S