CLUTCH SLIP UNDER LOAD AT 7K RPM

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Magonsterz!

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Finally got her back together, start, stops, idles, cools and drives geart under normal driving, spot on.

Seems to be slipping but only at higher RPM's (7-8k ish). This is of course under hard acceleration but only toward the end of the range for the gear...in other words it happens just about the time I'm ready to shift up.

It seems like the clutch would be most likely to slip when first engaged in a gear...not when I'm almost out of it and it's been pulling hard (and fully engaged).

Slipping clutch at 7k while under full throttle acceleration except 1st.

Handle bar shift is butter smooth, lever has about 3/8 to 1/2 in slack, shifts through all gears with no prob up and down, cable is smooth and free of hang ups.



If I roll out hard in 1st, no problem.

Speed shift into 2nd and just stays at 7k for a sec then slips all up to 8k, winding out but not speeding up but if i stay in it eventually feels like starts to bite and pulls while pegged at 8k.



If i roll through 1st to 5th normally AND briskly BUT NOT speed shifting, zero issues, rolled out nice and swiftly.



Is my clutch wearing out or is this something else?

Any ideas what cause may be? Using fresh 15w40 Rotella conventional oil.

Going to drop rear cable to shift lever cover, reset throw to 5/8 slack/travel but seriously dont think it will help.
 

dan filipi

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Does the oil have friction modifiers? The oil needs to be ok for a wet clutch.
Mine slipped like that when the engine power output is at its highest. I had mistakenly used the wrong oil. The slip stayed after changing it even after a few times. Seemed to eventually go away.
Other than that, your clutch plates may need changed or the springs could be weak.
 

Magonsterz!

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[url=https://www.classicgoldwings.com/forum/viewtopic.php?p=219063#p219063:3sg3fmib said:
dan filipi » Today- 6:45[/url]":3sg3fmib]
Does the oil have friction modifiers? The oil needs to be ok for a wet clutch.
Mine slipped like that when the engine power output is at its highest. I had mistakenly used the wrong oil. The slip stayed after changing it even after a few times. Seemed to eventually go away.
Other than that, your clutch plates may need changed or the springs could be weak.

used Shell rotella 15w40 conventional but read jug and lower half of SAE donut has "CI-4" additive instead of being blank, looks like ill have to drain, swap filters and refill will recommended 5w40 zero additives conventional.
website says 15w40 conventional has the following:
"CK-4, CJ-4, CI-4 Plus, CI-4, CH-4; ACEA E9; JASO DH-2, MA, MA2; Caterpillar ECF-2, ECF-3; Cummins CES 20086, 81; Detroit Fluids Specification (DFS) 93K222, 93K218; Deutz DQC III-10 LA; MACK EO-S 4.5, EO-O Premium Plus; MAN M3575; MB-Approval 228.31; MTU Category 2.1; Allison TES-439; Volvo VDS-4.5, VDS-4, Ford WSS-M2C171-F1"

Another member recommended dump in 4 oz of Sea Foam to the current oil, maybe even to the 2nd Reflush oil to get rid of all of the "super slippery modifiers"

glad to hear yours eventually cleaned out.
 

desertrefugee

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The first symptom you usually see with a slipping clutch will be in higher gears under heavy throttle.

Think of riding a bicycle in a high gear and how much horsepower/leg power is required to make the wheel turn as opposed to shifting lower. Same thing on a motorcycle. That much horsepower expended to maintain speed will find the weak link - typically the clutch.
 

Magonsterz!

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Alright, was able to drain, swap filter and fill with Rotella T4 15w40 with NO ADDITIVES (kin to the T6 full synthetic) with 4 oz of Seafoam (how much is too much?) to 3.7 quarts of oil, put 30 miles on her before the sunset on me today. Ran it through its paces, will see 100 miles before i change out for same combo in hopes quits slipping. Real drag cuz i like to winderout and let the pipes sing :/
Thanks again for the advice, much appreciated.
 

pidjones

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Around 7k is peak horsepower and max strain on clutch. I've used Rotella T4 (white jug) for years with no problem, but seldom rev over 6500 when shifting. BTW, you listed M2 as one of the specs. Isn't that motorcycle wet clutch?
 

Magonsterz!

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[url=https://www.classicgoldwings.com/forum/viewtopic.php?p=219078#p219078:3dnx440e said:
pidjones » Today- 3:13[/url]":3dnx440e]
Around 7k is peak horsepower and max strain on clutch. I've used Rotella T4 (white jug) for years with no problem, but seldom rev over 6500 when shifting. BTW, you listed M2 as one of the specs. Isn't that motorcycle wet clutch?

i think it lists it as "MA2" not sure what the diff is, but do know that the lower section of the "SAE DONUT" on the back has the "CI-4" in the lower section of the symbol which i believe is a friction modifier that may be causing slip.
I like to wind out the revs as long as she is pulling so i may go with beefier clutch pack from Barnetts. A bit more clutch pull tension but a fair trade off.
Barnett:
Spring kit: 501-56-06015
Friction plate kit: 302-35-10002
and if needed Tempered Steel Metal Plates kit: 401-35-078024
Decent write up on it
https://www.ngwclub.com/forum/viewtopic. ... 007298db35
 

desertrefugee

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Yeah, I always look for oils that have blank lower circles on the “composition shield”. I believe anything there at all indicates the presence of friction modifiers - which are not good for wet clutch packs.
 

[email protected]

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Almost certainly weak clutch springs. My son just had the same exact symptoms on his '78 CB400 Hawk. New clutch springs was all he needed, and it's working perfectly again! He and I both use Mobil-1 4T MA/MA2 oil in all of our bikes,
 

ckahleer

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MA is for motercycles with wet clutches. It also has a high zinc content to better lubericate cam lobes and rocker faces.
MA2 is for newer motorcycles with catalytic converters and O2 sensors. Zinc is harmful to O2 sensors, so MA2 has a lower zinc content.
I don't know how an oil can be both MA and MA2 since one has high zinc and the other low zinc, but most motercycle oils do carry both ratings.
 
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