Stock clutch is on its last legs

A place for LC enthusiasts to hang out!

Moderators: rztom, 2smoke

Message
Author
Bloke
Posts: 21
Joined: Fri Jul 29, 2016 12:44 pm

Stock clutch is on its last legs

#1 Post by Bloke » Sun Feb 05, 2017 10:21 pm

My 81 Elsie has 20k on it now and the clutch is starting to slip, more when the tranny oil is cold and thicker but anyway it's time for an upgrade, is the Barnett kit any good? I'd go EBC but can't find the kit available here in the USA
Last edited by Bloke on Mon Feb 06, 2017 12:11 am, edited 1 time in total.

User avatar
JonW
Posts: 10599
Joined: Sat Oct 10, 2009 4:33 am
Location: Sydney
Contact:

Re: Stock clutch is on its last legs

#2 Post by JonW » Sun Feb 05, 2017 11:07 pm

i bet the plates are ok, its your springs.... check their lengths.
80 XT500 Supermoto!
81 RD350LC Resto
82 RD421LC Hybrid
82 RD350LC decapitation project
82 RD250LC JDM '251LC' YPVS
83 RZ350 Resto
84 RZ500 Resto
85 RZ350 F1 Resto
86 RZ350 F2 Resto
86 RZ350 F2 Hybrid

Like Watches? www.PloProf.com & www.DeskDivers.com

Bare
Posts: 1196
Joined: Sun Jan 29, 2006 2:18 am
Location: vancouver

Re: Stock clutch is on its last legs

#3 Post by Bare » Mon Feb 06, 2017 12:08 am

Bloke wrote:My 81 Elsie has 20k on it now and the clutch is starting to slip, more when the tranny oil is cold and thicker but anyway it's time for an upgrade, is the Barnett kit any good? I'd go RBC but can't find the kit available here in the USA
NO it is not. Others may claim it's better than sex.. feeling lucky?
Buy and fit a new set of Yamaha FZ600 frictions. End of Clutch problems.. period.
Do Not dick with the springs, That just Effs up one of the best features of these bikes.. their light clutch action.

Bloke
Posts: 21
Joined: Fri Jul 29, 2016 12:44 pm

Re: Stock clutch is on its last legs

#4 Post by Bloke » Mon Feb 06, 2017 12:12 am

Just stock Yammy fzr600 plates? Any particular year?

hondaror
Posts: 2828
Joined: Mon Mar 03, 2014 8:44 pm
Location: Alberta, Canada

Re: Stock clutch is on its last legs

#5 Post by hondaror » Mon Feb 06, 2017 12:35 am

Go springs!!! Check plates. Springs are the weakest point on the clutch. Any blue on the steels, replace them.

'78 TZ250 springs cleared all my clutch issues.
Rory
2 1984 RZ350s
1985 RZ350
9 1986-1990 RZ350s
2000 ST2
2005 749
2005 749 with 999 engine

Bloke
Posts: 21
Joined: Fri Jul 29, 2016 12:44 pm

Re: Stock clutch is on its last legs

#6 Post by Bloke » Mon Feb 06, 2017 12:40 am

Anybody know if RZ350 springs are the same as LC350 springs?

User avatar
Zedixe13
-----
-----
Posts: 688
Joined: Wed Jan 16, 2008 1:39 am
Location: Quebec city Canada

Re: Stock clutch is on its last legs

#7 Post by Zedixe13 » Mon Feb 06, 2017 1:22 am

Yes same springs , the FZ600 1986-88 .

http://www.partzilla.com/parts/search/Y ... parts.html" onclick="window.open(this.href);return false;

User avatar
JonW
Posts: 10599
Joined: Sat Oct 10, 2009 4:33 am
Location: Sydney
Contact:

Re: Stock clutch is on its last legs

#8 Post by JonW » Mon Feb 06, 2017 2:15 am

Bare wrote:
Bloke wrote: Do Not dick with the springs, That just Effs up one of the best features of these bikes.. their light clutch action.
Not suggesting anyone dick with springs, get the OEM ones... just saying in the 8 -10 clutches i measured almost all the plates were fine and it was the springs that were screwed.

Dont waste money on plates you dont need is what im saying...
80 XT500 Supermoto!
81 RD350LC Resto
82 RD421LC Hybrid
82 RD350LC decapitation project
82 RD250LC JDM '251LC' YPVS
83 RZ350 Resto
84 RZ500 Resto
85 RZ350 F1 Resto
86 RZ350 F2 Resto
86 RZ350 F2 Hybrid

Like Watches? www.PloProf.com & www.DeskDivers.com

Angus McL
Posts: 47
Joined: Fri Mar 21, 2014 11:08 am
Location: Halifax, NS, Canada

Re: Stock clutch is on its last legs

#9 Post by Angus McL » Fri Feb 10, 2017 3:29 pm

I went with 3 stock springs and 3 heavy (TZ maybe??) springs from Yambits... Dont go that route!!! Damn the clutch pull is heavy now! A real bitch in traffic!

A.

hondaror
Posts: 2828
Joined: Mon Mar 03, 2014 8:44 pm
Location: Alberta, Canada

Re: Stock clutch is on its last legs

#10 Post by hondaror » Fri Feb 10, 2017 4:09 pm

That's the price you pay for a clutch that works as it should. It's not that bad when the engine is running.
Rory
2 1984 RZ350s
1985 RZ350
9 1986-1990 RZ350s
2000 ST2
2005 749
2005 749 with 999 engine

Bare
Posts: 1196
Joined: Sun Jan 29, 2006 2:18 am
Location: vancouver

Re: Stock clutch is on its last legs

#11 Post by Bare » Fri Feb 10, 2017 5:24 pm

Frictions are cheapish.
Worn out ones measure at Very little less than Brand new ones.
Fitting larger Yamaha friction discs is a No brainer imo ..30% more friction area.
Which hold lots mo' power and even wear less.
What's not to like ?
One also gets to trashbin those worthless rubber damper rings Yama fitted for a few model years.
IF convinced that the pore springs are knackered (I remain skeptical that they often are)..
Measure 'em and if so a simple corrective bodge would be to fit a washer under them.

That will increase the spring preload, without Effing up the clutch feel.

No need.. to take the Brute force approach.

hondaror
Posts: 2828
Joined: Mon Mar 03, 2014 8:44 pm
Location: Alberta, Canada

Re: Stock clutch is on its last legs

#12 Post by hondaror » Sat Feb 11, 2017 4:40 am

Oh don't do the washer bodge. If they wear and break up, you'll have carnage to deal with. Trust me, buy a new set of springs.
Rory
2 1984 RZ350s
1985 RZ350
9 1986-1990 RZ350s
2000 ST2
2005 749
2005 749 with 999 engine

MK
Posts: 814
Joined: Sat Nov 26, 2005 11:44 am
Location: Wolfenbüttel, Germany
Contact:

Re: Stock clutch is on its last legs

#13 Post by MK » Sat Feb 11, 2017 2:47 pm

How about trying new gearbox oil first?
Doesn't cost a fortune and has potential to cure your symptoms immediately.

I use Bel Ray Gear Saver 80W transmission oil. Its somewhat lighter than the recommended 10W30 and reduces both clutch slip and drag (i.e. heavy shifting when standstill and engine is running).
I even had one case where those negative symptoms occurred after switching to Motul Transoil and were disappeared after going back to Brl Ray.

Otherwise the usual cause is worn springs (they sag in length and thus loose preload) or warped steel plates. Rarely saw worn friction plates.
Unfortunately aftermarket steel plates can be very poor quality - I once had a case where I ended up in just using a few new and some of the old plates after checking which were warped (yes, you understood right: new plates come in warped state!)
Also worth a check: the double roller bearing behind the clutch. Had some failures here recently which affected cluch actuation.

Regarding "kits", I use/used Barnett, EBC and OEM. All work just fine.
The Barnett Kevlar stuff is proved to bear even 90 hp with stock clutch setups.
If you want to improve things without more lever force, get extra plate kits (which requires a new basket & inner part) or a lock-up plate (requires modified/new clutch cover)
Bye
Martin

Bare
Posts: 1196
Joined: Sun Jan 29, 2006 2:18 am
Location: vancouver

Re: Stock clutch is on its last legs

#14 Post by Bare » Wed Feb 15, 2017 1:13 am

hondaror wrote:Oh don't do the washer bodge. If they wear and break up, you'll have carnage to deal with. Trust me, buy a new set of springs.

OK I'll bite :-) Why would mild steel washers wear and break up ? What possible in use condition would do that ?
Valve springs universally have a steel washer betwixt the spring and the ali head. :smt002
Yet Yama's have neither a steel bearing surface for the OEM springs NOR even the first clutch Friction.
Clearly Yama didn't overspend
Not saying it's the cleverest of bodges... or that the OP should do it. Just a possible, poor man's patch.
Other method to increase stack pressures would be to use the larger And thicker OEM Steels from a yama Fz to R6
Steels however, unless Visibly damaged/blued are V durable. There is also the possibility of fitting an Extra friction (yes it Fits, with small flycutting of the pressure plate)
Frictions.. do wear. Use a decent micrometer.
Ferodo makes FZ600 /early R6.. Race frictions available for affordable prices. A brand name with provenance :-)
Agree.. Use gear type oils. Suggest: easy to find AutoParts shop GL4 Gear oil 75/85w because it's cheap, easy and.. effective.
Even available in synth formulations, if inclined to that.
IMO every yama should run this without question.

User avatar
JonW
Posts: 10599
Joined: Sat Oct 10, 2009 4:33 am
Location: Sydney
Contact:

Re: Stock clutch is on its last legs

#15 Post by JonW » Wed Feb 15, 2017 1:44 am

Bare wrote:
hondaror wrote:Oh don't do the washer bodge. If they wear and break up, you'll have carnage to deal with. Trust me, buy a new set of springs.

OK I'll bite :-)
Frictions.. do wear. Use a decent micrometer.
I'll bite too... they have a specification, even a half decent micrometer will tell you its in or out of spec. I never said they didnt wear, just that I bet they would be ok and the springs were flogged out. The OP hasnt come back yet, Im keen to hear what he has to say after measuring the parts.
80 XT500 Supermoto!
81 RD350LC Resto
82 RD421LC Hybrid
82 RD350LC decapitation project
82 RD250LC JDM '251LC' YPVS
83 RZ350 Resto
84 RZ500 Resto
85 RZ350 F1 Resto
86 RZ350 F2 Resto
86 RZ350 F2 Hybrid

Like Watches? www.PloProf.com & www.DeskDivers.com

Post Reply