Clutch slipping after 8 pack upgrade

[perkinja]

So i bought the 8 pack clutch kit from ironheart cycles which came with the following:

• 8 new clutch plates
• 1 new steel plate
• springs/retainers
• thrust bearing/washer

I have a 79 2f so it was a pretty easy install. I measured my old steel plates at 2.96-2.98, slapped it all together and for the first month everything was fine. But lately it has started to slip occasionally. It only slips in 1st gear when i'm taking off from a stop and it doesn't do it every single time. After the bike has warmed up I notice it more which is making me think that it could be my oil. I've tried adjusting it at the worm gear and the clutch lever with no success. If it is oil, will I need to do anything to the friction plates like clean them with something and then re soak them?

 

[weekendrider]

Out of curiosity, what oil are you using?

 

[perkinja]

Castrol 20w-50

 

[weekendrider]

The 4T motorcycle oil? I use it in a motor that has Ippytattoo's 8 pack conversion and it hasn't had a problem. Or should say didn't have a problem, that bike has been in storage for 18 months.
Or is it the Actevo syn blend?

 

[perkinja]

Yep that's the stuff. Put it in over the winter in preparation for the summer.

 

[weekendrider]

I've used that oil in several and never had an oil related slip. The clutch slip I've experienced has always been in the top of 4th and 5th. The cure new springs.

 

[perkinja]

Yeah it's what ive used since I've had the bike and have never had problems with it before. I'm just not sure what it could be.

 

[TwoManyXS1Bs]

You have too much horsepower.

Remove (1) sparkplug...

 

[perkinja]

You have too much horsepower.

Remove (1) sparkplug...

Haha

 

[TwoManyXS1Bs]

... I measured my old steel plates at 2.96-2.98...

???

They should measure about 1.35-1.4mm...

 

[perkinja]

???

They should measure about 1.35-1.4mm...

You are correct my apologies, I'm looking back at my notebook and I cant for the life figure out where i got those numbers from. I'll go remeasure them right now to make sure they are correct.

EDIT: you are correct, all just a hair under 1.4, only thing that was close to 3 was the old friction plates.

 

[TwoManyXS1Bs]

I'm not sure if this applies to your plates, but here's some discussion about Alto plate friction material:

http://www.xs650.com/threads/alto-8-pack-clutch-kits.33806/page-4#post-397516

 

[perkinja]

I'll give that thread a look through. Thanks TwoMany.

 

[perkinja]

Ive probably read every thread under the sun regarding 8 pack clutches and the only thing I can come up with is the oil.

 

[MaxPete]

Yep that's the stuff. Put it in over the winter in preparation for the summer.

Sorry...your answer wasn't clear: are you using the synthetic or the conventional oil?

If it is the synthetic and it has a label that say "Energy Conserving" or "Reseource Conserving" - you'll have to change it because oils with that label are not compatible with motorcycle wet clutches.

If the oil is ok - then perhaps your clutch simply needs to be adjusted.

 

[perkinja]

So I finally got home from work (had to spend the last month in Kansas for work) and got the chance to fiddle with it some more. I've adjusted the clutch per what my manual says, changed my oil and it's still doing it. Could the fact that I replaced my rear sprocket with a 31 tooth from the stock 34 to lower my highway RPM's be it? The only reason I say this is because I can force this slipping now every time if I want to.

From a take off, if I twist my throttle about an 1/8th of the way and let out on my clutch it will slip. But if i just give it barely any throttle (i'm talking like none at all just letting my idle do all the work) and slowly let out on my clutch nothing happens but I take off incredibly slow.

 

[TwoManyXS1Bs]

I'm wondering if there may be an issue with clutchpack stackup thickness and pressure plate position/travel.

The normal stackup thickness is from 29.0mm to 29.4mm.
Not sure what it should be for the 8-plate clutch, what with the hub resurfacing.

The pressure plate should be operating in a limited "sweet zone", not so deep where it would bottom on the hub and prevent clamping the clutchpack, not so far out as to uncouple with the hub's splines. We get into that here:

http://www.xs650.com/threads/clutch-pressure-plate-travel.48508/

 

[perkinja]

I have to head back to Kansas in the AM, I think when I get back I will throw on the 34 tooth rear sprocket and see if the slipping is still there. If it is, Ill throw in my old 7 pack and see if it still exists. I read through that thread and before I swap out plates i'll measure the thickness and see if it comes out to 29 mm.