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Discussion Starter · #1 ·
I think my clutch could be slipping at high speed. It's been doing this for a bit. I'll have it pegged in 4th 5th or 6th and the bike will wind through the gears normally then when it hits high rpm it'll rev up quickly and the bike feels like it just goes from being in the powerband to only applying a portion of power.

So I mic'd my frictions and they're all well past minimum spec, same for the steels, a steel or two does have some scratching on a portion of them but no blueing. Can a clutch slip while still having a ton of meat on it?

The engine isn't missing a beat in all of this as far as I can tell, no misfiring, backfiring, popping, no smoking no funny noises. I did throw some ebc springs in it but this problem was rearing its head beforehand.

It's an 05 gsxr 600
 

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Discussion Starter · #5 ·
Yeah they matched just fine, this problem was occurring before the change so they didn't cause it; I'd heard a lot of good things about them and they were true, it has been an improvement. I would recommend them, the clutch just seems far more responsive and snappy.

I'm not sure what to think of it, when I hear the word slipping first thing I think of is the clutches being worn out but these clutches are still within spec. It's not slipping out of gear, the engine revs up like load has been lessened and bike loses some power.
 

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watches you sleep.
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Wait you have a wet clutch and youre running fully synthetic for a car? Thats probably your problem right there. Fully synthetic oils are meant to super lubricate all the moving parts it comes in contact with. Your clutch fibers and plates need to grip. When theyre soaked with a fluid made to super lubricate with as little friction as possible, your clutch isnt able to do its job.

The first thing I would do is change your oil to a conventional. Ive been running Valvoline for a long time with no problems. While youre crankcase is empty youre also gonna wanna pull those clutch plates again and get all the synthetic oil out that you can. Also check your clutch springs to make sure theyre in spec.

Are there a lot of other guys here running fully synthetic car oil in their bike? I've ALWAYS been told its the wrong thing to do as it will make your clutch slip.
 

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Discussion Starter · #10 ·
Yeah my clutch cable slack is set right the clutch is fully engaging/disengaging. You can fit a nickel between the lever and all that.

I'm wondering if maybe the synthetic oil could be making it slip? If the clutch has seen nothing but conventional all the way up to my ownership? The bike was a stunt bike before me, about 17k miles. But 4t has wet clutch ratings, it damn well better for $10 a quart!

And yeah never use car oil in a bike, I have heard of diesel oil working great from an old track runner but it still seems a bit iffy
 

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Penta-personality
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When you took your plates out to measure them and install the new springs, did you put them back in the same exact order? If so, try re-arranging some of the frictions and steels. I had the same symptoms start happening to my bike a few seasons ago - at first I thought the rear tire was breaking loose/losing traction (SO MUCH POWAAHHH!!!), but quickly realized it was the clutch that was slipping. Moved some of the plates around and it's not done it since.
 

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ShamanFighter
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I Had a Clutch Take a Dump on me after 3k miles of ownership. what you are describing is the clutch slipping.
i would put a heavy duty set of springs in it and see what it does.

i replaced my clutch with dp clutch fibres and barnett springs and boy was it a world of change...
 

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Discussion Starter · #14 ·
When you took your plates out to measure them and install the new springs, did you put them back in the same exact order? If so, try re-arranging some of the frictions and steels. I had the same symptoms start happening to my bike a few seasons ago - at first I thought the rear tire was breaking loose/losing traction (SO MUCH POWAAHHH!!!), but quickly realized it was the clutch that was slipping. Moved some of the plates around and it's not done it since.
Nah, I mixed the plates up except for the two that are supposed to be the first and last friction. Howd your plates look when you removed them? Were a few thinner than other?

I Had a Clutch Take a Dump on me after 3k miles of ownership. what you are describing is the clutch slipping.
i would put a heavy duty set of springs in it and see what it does.

i replaced my clutch with dp clutch fibres and barnett springs and boy was it a world of change...
I got the heavy duty ebcs installed currently, they're supposed to be 10-15% stronguh; they're definitely an upgrade but the issue still exists. It's not even a major slip, once she hits that 13k rev in 3-6th gear the revs jump and power is lost; whats a man to do with no power?! I've ordered some new frictions, I was reading a post the other day about a guy who had some slipping in the top end and his plates were still past spec.

Turns out that frictions can become hardened (from heat? use?) which causes them to lose their grip and start to slip. I ordered some DP frictions like you, they're a serious brand, couldn't go wrong with em
 

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ShamanFighter
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Turns out that frictions can become hardened (from heat? use?) which causes them to lose their grip and start to slip. I ordered some DP frictions like you, they're a serious brand, couldn't go wrong with em
yup, that can happen. were your steels blued at all?
 

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Yeah my clutch cable slack is set right the clutch is fully engaging/disengaging. You can fit a nickel between the lever and all that.

I'm wondering if maybe the synthetic oil could be making it slip? If the clutch has seen nothing but conventional all the way up to my ownership? The bike was a stunt bike before me, about 17k miles. But 4t has wet clutch ratings, it damn well better for $10 a quart!

And yeah never use car oil in a bike, I have heard of diesel oil working great from an old track runner but it still seems a bit iffy
Mobil 4T made the clutch slip like crazy in my Vmax even with a stiffer spring. Switched to Rotella 15-40 conventional (diesel) oil, slipping vanished just like that. Neutral became much easier to find as well.

Car oil is perfectly fine in a bike. There is no such thing as motorcycle-spec oil, it's a meaningless marketing term. Your owners manual will specify a normal automotive oil spec. SF/SG for older bikes, though the current spec is SN.

Diesel oils contain more ZDDP which is an extreme pressure zinc lubricant. Great for your bike's compact transmission. They're also more resistant to thermal breakdown since most on-road diesels are turbocharged, great for air cooled bikes and the oilboilers.

So yeah Rotella is the shit. No reason to run anything else.
 

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Is my bike ok?
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i have only ran rotella in every bike ive owned.
Same here. It works well, holds up to heat great (think air cooled), $12/gallon and I can pick it up at Walmart at 2 in the morning.

The reason Rotella is safe for bikes is because it's designed for use in tractors and earth moving equipment, a lot of which run wet clutches.
 

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Penta-personality
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Nah, I mixed the plates up except for the two that are supposed to be the first and last friction. Howd your plates look when you removed them? Were a few thinner than other?
Mine looked mostly normal, with only a few small blued hotspots here and there. I didn't even bother to measure the thickness - I ordered all new frictions, steels & springs, but I haven't even put them in yet - maybe next season.
 

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Discussion Starter · #20 ·
yup, that can happen. were your steels blued at all?
Nah not at all, I got the new dps in and I also caught a good deal on a manual cam chain tensioner and this bike is completely different. Way more peppy and the slipping is all but gone.

The tensioner itself was a definite upgrade, the bike vibrates less, my right hand doesn't go numb anymore on long trips and thats without bar ends.
 
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