Gear Oil for Clutch.

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hondaror
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Re: Gear Oil for Clutch.

#16 Post by hondaror » Fri Jul 28, 2017 2:50 am

What makes the clutch slip? Under sprung springs or worn friction plates. More times than not, it's the springs. Heavier oils cause more drag and thus hp loss.
For years, I ran 1 litre of 10W30, down from 1500 ccs in my LC. Went through 3 sets of springs until I put TZ250F springs in. Never any more problems.
I suspect the slippage is spring related.
What oil you run, should be related to what you are looking to achieve. I'm a less drag kind of guy. Optimum performance. I'm trying to decide what oil ratio to run in a premix engine. I'm going to use Motul 800. I may try 60:1, pretty much unheard of amongst the racers out there. They all like gobs of oil to protect their engine parts. I like performance. Didn't I say that already?!
It's important to change the tranny oil every season.
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evan_calgary
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Re: Gear Oil for Clutch.

#17 Post by evan_calgary » Fri Jul 28, 2017 11:13 am

The oil will and does matter. It may not in the RZ but it does in the TZR. Not to hate but I don't think any of you guys have experience with the TZR other than John. Well documented with the TZR that oil WILL impact clutch slip. Do I know why? Not a chance but it certainly does affect. Logically it makes sense as there will always be a skim of oil between the plates in your clutch that impacts stiction.

silverstrom
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Re: Gear Oil for Clutch.

#18 Post by silverstrom » Fri Jul 28, 2017 2:20 pm

Any stock bike will not clutch slip with stock springs and friction plates if you use the proper oil. If you use an automotive oil meant for cars and it has friction modifiers your clutch will slip and once that oil is in your friction plates the only solution is to replace them or it will slip forever. If you must use regular oil make sure it is for motorcycles if you want to save your friction plates and stop slipping. If the only way to prevent slipping is to use far stronger springs you either have poor clutch adjustment, a very powerful engine, or the wrong oil was used and the friction plates are contaminated.

evan_calgary
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Re: Gear Oil for Clutch.

#19 Post by evan_calgary » Fri Jul 28, 2017 5:05 pm

Totally agree with you John. Going to use some proper oil.

Experience with NOT slipping with regular automotive oil does NOT mean it is correct or the solution for everyone.

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T.RexRacing
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Re: Gear Oil for Clutch.

#20 Post by T.RexRacing » Sat Jul 29, 2017 8:33 am

Second guessing engineers is often an exercise is frustration. 10W30 Yamalube is what's recommended. If you believe an 70 weight gear oil is thicker you're mistaken. It's tested with different standards (hence the number) and is as viscous as a typical 40 weight motor oil.
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Re: Gear Oil for Clutch.

#21 Post by evan_calgary » Thu Aug 03, 2017 3:54 pm

John said basically the same thing above.

Looks like springs may have been my issue. I picked up some heavier F3 springs and they appear slightly longer. I suspect the stock ones have shrunken. Most of the slip was when the bike was hot. Would that also indicate springs? Clutch plates have enough thickness but with a slipping clutch this doesn't necessarily mean they were not part of the problem as they are full of oil.

Off to get some oil and rebuild the clutch.

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Re: Gear Oil for Clutch.

#22 Post by LC Cnd » Fri Aug 04, 2017 5:22 pm

Well decided on replacing the 10-30 Royal Purple with Amsoil Severe Gear 75/90 at the 500 mile oil change. Your right John its not cheap ($26 Cnd) but will give it a go with the Barnett heavy spring clutch kit. Did not have any slippage with Royal Purple. Hopefully all will work out with you Evan.

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Re: Gear Oil for Clutch.

#23 Post by ZedSledder » Fri Aug 04, 2017 5:52 pm

Is there a motorcycle specific severe gear. I can't find one. So I went with what was offered in the catalog. I dumped that stuff in the recycle bin at the marina after 50km. I was getting foam on my dip stick, not mention it smells like the focsle on a freezer boat. That smell induces nightmares in me after my commercial fishing days.
Just wondering if there is a motorcycle specific one?
1985 Canadian Rz350. Restored with collector plates. Stock VM26, Triumph Calipers, Galfer brake lines. Brand new DG’s, 260 main, 22.5 pilot jet. Economy pre-load adjusters. Ohlins shock. Oem Banshee crank.

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Re: Gear Oil for Clutch.

#24 Post by bitzz » Sat Aug 05, 2017 11:35 am

I only use a modern gear lube, usually Lucas synth.
I am not second guessing anyone, I am acknowledging that there has been HUGE advancements in lubricants since these transmissions were designed in the sixties.

If you are going to use "gear lube" be sure to use something rated GL4, because of the yellow metal in the trans.

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JanBros
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Re: Gear Oil for Clutch.

#25 Post by JanBros » Sat Aug 05, 2017 8:42 pm

I always put ATF in 2-stroke gearboxes.

what is inside an automatic transmission ? gears and clutchplates ... :smt002
if it runs, you can race it !

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Re: Gear Oil for Clutch.

#26 Post by T.RexRacing » Sat Aug 05, 2017 8:57 pm

bitzz wrote:I only use a modern gear lube, usually Lucas synth.
I am not second guessing anyone, I am acknowledging that there has been HUGE advancements in lubricants since these transmissions were designed in the sixties.

If you are going to use "gear lube" be sure to use something rated GL4, because of the yellow metal in the trans.
Run whatever ya like. However one question does come to mind..............won't the 10W30 oils on the shelf near the gear oils carry those same advances referred to? Huh? ya think?
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silverstrom
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Re: Gear Oil for Clutch.

#27 Post by silverstrom » Sun Aug 06, 2017 12:29 am

Gear oils are engineered for the shear forces of gears. Engine oils are not.

There is no good answer. Everyone likes what they like. This is exactly why oil threads are pointless.

Next we can debate the uselessness of paying to put nitrogen in your tires.

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Re: Gear Oil for Clutch.

#28 Post by T.RexRacing » Sun Aug 06, 2017 10:19 am

All motor oils are engineered to resist shearing. Synthetics by the way they're designed/manufactured with straight polymer chains and mineral oils by viscosity index improver additives which bind the polymer chains. Gearsets are not the most severe shearing actions an oil will see. That is present under high power (especially turbo/supercharged) in the hydrodynamic wedge deterioration that eventually becomes bearing failure.

There is a good answer however don't allow facts to interfere. Case in point. Modern 4 strokes sharing gearbox with plain bearing crankshafts. One of the most severe duties a off he shelf oil will experience. You believe that's not considered when spec'ing the additive package for manufacture?
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Re: Gear Oil for Clutch.

#29 Post by ZedSledder » Sun Aug 06, 2017 5:26 pm

Amsoil is good stuff. I reckon I probably bought the wrong gear oil. Maybe it mixed with trace oil of what I had used previously.... causing the foaming.

Amsoil Interceptor works great. I also like their blue fork oil, helps to track down if its fork oil or brake fluid should leaks occur. The guy who tunes the Zokes on my dirtbike won't touch it, but I have no problem putting it in my rz. The dirt bike gets the amsoil 10w60, works great.

Sorry wasn't trying to rock the boat, just trying to figure if I bought the wrong stuff. No biggie. the gear oil i got from amsoil was GL 5.
1985 Canadian Rz350. Restored with collector plates. Stock VM26, Triumph Calipers, Galfer brake lines. Brand new DG’s, 260 main, 22.5 pilot jet. Economy pre-load adjusters. Ohlins shock. Oem Banshee crank.

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Re: Gear Oil for Clutch.

#30 Post by T.RexRacing » Sun Aug 06, 2017 6:01 pm

That actually made me think about synthetics vs. mineral gear lubes. The additive in GL5 oil that's harmful to yellow bearings/bushings is a sulfate and I'm not sure it's necessary in a synthetic. But it is one of the ingredients that gives gear lube it's distinctive odor. I sent Amsoil an e-mail and I'll post up the results.
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