Slipping Clutch

[addonii]

Since this area has been somewhat dead I thought I would post re: the slipping clutch on my 1300.

I have been riding this 1300 since spring of 2010 and periodically I have experienced clutch slippage when I go wide open throttle in 2nd, 3rd and 4th gear (I’ll not comment on the speed).

I cured the slipping by replacing the OEM original clutch springs with NEW OEM clutch springs.

What I found interesting is the springs according to the ZN1300 shop manual are supposed to be 33.6mm Standard with a 32.6mm Service Limit.

The 5 OEM original springs I took out of the bike were all between 33.4mm & 33.5mm unfortunately I don’t have a device to check the actual spring pressure.

All the New OEM spring measured between 33.6mm and 33.65mm – so I find it amazing that the small discrepancy made the difference.

While I was in the clutch I checked all the steel and cork plate and they were within spec’s.

I was happy to see that none of the steel places showed any discoloration due to the slipping.

If any body out there wants to do the clutch work all you need to do is lay the bike over on it’s left side with a 4” X 4” piece of wood under the left crash bar and you have the bike leaned over far enough so you won’t loose any oil.

If you do the clutch make sure you have a new clutch cover gasket on hand as more than likeley part of the gasket will stick to either the engine case and another part will stick to the cover breaking the gasket when you remove the clutch cover. Having the gasket on hand is just good practise anyway.

If the new OEM springs hadn’t cured the problem I would have installed a set of EBC clutch springs or Vesrah Heavy Duty Clutch springs which are supposed to be a little strong than the OEM springs.

Since the clutch is not slipping I haven’t installed either the EBC or the Vesrah springs but have them on hand just in case.

[Old Nyk]

Found a nice bit of info on this site
North American TurboCoupe Organization
how Valve springs are checked.
The Guy was using a Rimac Spring Tester and shows usefull photo's of actually using the equipment on Valve Springs.Would think it could be used for Clutch Springs as well.I'm not an expert,just passing on what i have found.Best wishes.Old Nyk.

[addonii]

I used to check the clutch springs back in the 70's when I was working on motorcycles for a living with a device very similar to the Rimac item mentioned that gave me the compressed pounds at a certain length so once you had that for a spring you could compare not only the length but also the "weight/pressure" excerted by the clutch spring - very similar to the valve springs which also should be checked not only for length but also pressure excerted.

If anyone is interested the article mentioned the previous post you can find it here:

http://natomessageboard.com/ultimatebb. ... 056#000000

I would imagine a poor mans version of the tool could be constructed from a cheap arbor press (Harbor Freight 1/2 ton press for about $28.00) and some sort of a pull scale attached to the handle or an adapter to use a old style beam scale type torque wrench with an appropriate adapter.

All readings would be relative to each other but not necessarily useful unless you have a way of relating your measurements to a real spring checker. It would be useful for comparing a good new spring to a used suspect spring.

I bring this up because of the cost of such a device. I have spotted valve spring testers on eBay and else where costing anywhere between $100.00 to $1,000.00 depending on features and whether new or used. The Rimac Spring Testers noted in the previous post cost anywhere from $100.00 to $500.00 again depending on features and if new or use.

Thanks for the information.

[trikebldr]

This is an old thread, I guess, but worth waking up. I came here to see if anyone else has had the problem my 1300 had when I got it used. The dealer warned me the clutch slipped pretty easily under moderate to heavy throttle.

Sometimes this is due to people using some of the synthetic oils or using an additive, like Motor Honey or STP. Those will ruin a clutch in no time! They penetrate the non-metallic surfaces of the plates and you can't wash it off well enough. The steel plates will clean off just fine, but you have to replace all the "friction" plates. Some guys claim you can get by just changing the oil. Didn't work for me, even after three changes. (don't worry, the oil won't go to waste! It's saved for my mowers!). I have a whole new clutch, springs and basket coming.

[doug of so fla]

Just to throw in $.02 worth, If it is a hydraulic acuated clutch system, most of the time, clutch slippage can be due just to the hydraulic fluid being old & all gunked up and full of air & water either in the reservoir or clutch slave cylinder. First thing to do before going into the clutch, just in case!!

Should have added if cable actuated, make sure ALL cable adjustments and linkage are CORRECTLY adjusted!!. Have found many, that some one went WAY the wrong way and it just needed correct adjust & lube.. A worn lever pivot pin on either hyd or cable can throw the movement off enough to make it slip or "Clank" into gears. Most missed maint item on a M/C.. (CLUTCH LEVER PIVOT PIN) & easiest to do, at least twice a year.. were up to $.04 now!!

[trikebldr]

This is on an all-mechanical, cable actuated clutch.