NC30 clutch issue

Forum rules
Please can you post items for sale or wanted in the correct For Sale section. Items / bikes for sale here will be removed without warning. Reasons for this are in the FAQ. Thanks
Smoky
Familiar Member
Posts: 263
Joined: Wed Sep 24, 2008 9:43 am
Bike owned: NC30
Location: Hackney. East London
NC30 clutch issue

Post by Smoky »

afternoon all, just though some of the more learned amongst us may be able to shed some light on this situation.....


just had my clutch plates changed (friction and steels) for a second hand set in good condition- when clutch was rebulit there was tons of freeplay on the lever and now feels as if the springs are much tighter.
this in turn has reduced teh size of the biting point, so that the clutch is now more of an "off on" switch.
pulling away in first without stall or crunching the gearbox is exremely tricky when before the change it was fine.
i changed the plates because the clutch was slipping quite badly, and did find a couple of dead friction plates when i took it apart...

when i start the bike from cold there is not much freeplay in the lever, but after a few miles the freeplay keeps increasing, so i have to adjust it at the lever end on the fly....

anyone come across anything like this before?
Smoky
Familiar Member
Posts: 263
Joined: Wed Sep 24, 2008 9:43 am
Bike owned: NC30
Location: Hackney. East London
Re: NC30 clutch issue

Post by Smoky »

wow- no one?
thats a first...
User avatar
CMSMJ1
Moderators
Moderators
Posts: 7161
Joined: Thu May 01, 2008 9:42 am
Bike owned: NC30-No9
Location: Chesterfield, United Kingdom
Re: NC30 clutch issue

Post by CMSMJ1 »

lol.. patience... :peace:

err..but no, does the feeling come back when the bike is cold?

The clutch is a pretty solid bit of kit - you pull the lever, pulls the cable, turns the rod, pushes the actuator, opens the pressure plates.

Nothing in here is soft enough that it will become affected by heat?

Loose cover? loose clutch nut? dodgy cable?
IMPERATOR REX ANGLORUM

The V4 is the law..

NC30 - No9 - my old mate
Neosophist
Moderators
Moderators
Posts: 8172
Joined: Fri Jul 04, 2008 1:01 pm
Bike owned: CBR954
Re: NC30 clutch issue

Post by Neosophist »

Erm

Your post doesn't make much sense.
condition- when clutch was rebulit there was tons of freeplay on the lever and now feels as if the springs are much tighter.
this in turn has reduced teh size of the biting point, so that the clutch is now more of an "off on" switch.
pulling away in first without stall or crunching the gearbox is exremely tricky when before the change it was fine
It sounds like your new old clutch plates are knackered if the biting point is an 'on/off' feel. Did you measure the new old plates and friction disc thicknesses before you built it?

If they are fine it then sounds like it isn't assembled properly.

Heavy duty / stiff springs shouldn't make the biting point on an off, just make the clutch lever harder to pull in.
when i start the bike from cold there is not much freeplay in the lever, but after a few miles the freeplay keeps increasing, so i have to adjust it at the lever end on the fly....
Something seriously wrong here.

If your clutch cable needs to made tighter to operate the clutch as it is warming up it sounds like it isn't assembled properly.. at first i thought knackered clutch plates but I don't think they'd require the cable to be tightening up, although it could be both.

I'd really take everything back apart and follow the microfiche through when rebuilding everything.. having somone with you who doesn't speak bike might help, so long as they can read the pictures it helps when your putting things back together as they often catch mistakes someone technical wouldnt..
xivlia wrote:i dont go fast on this bike so really do not need a rear brake.. /
vic-vtrvfr wrote:Ask xivlia for help, he's tackled just about every problem u could think of...
Smoky
Familiar Member
Posts: 263
Joined: Wed Sep 24, 2008 9:43 am
Bike owned: NC30
Location: Hackney. East London
Re: NC30 clutch issue

Post by Smoky »

err..but no, does the feeling come back when the bike is cold?
the tension comes back yes- but the clutch it still very snatchy...
Loose cover? loose clutch nut? dodgy cable?
cover is on tight, clutch nut set to correct torque setting- cable is fairly new....
It sounds like your new old clutch plates are knackered if the biting point is an 'on/off' feel. Did you measure the new old plates and friction disc thicknesses before you built it?
mechanic measured them for me and said all was good...
Heavy duty / stiff springs shouldn't make the biting point on an off, just make the clutch lever harder to pull in.
lever isnt any harder to pull in, just seems like the tension from the springs comes in all at once...
Something seriously wrong here.

If your clutch cable needs to made tighter to operate the clutch as it is warming up it sounds like it isn't assembled properly.. at first i thought knackered clutch plates but I don't think they'd require the cable to be tightening up, although it could be both
clutch plates looked ok to me before they went in, and the mechanic who built the clutch has done work for me in the past and was spot on- but i suppose it could have been assembled wrong...

thanks for the replies gents- am getting the mechanic to open it up and have a look this weekend so will let you know how it goes.
cheers!
Neosophist
Moderators
Moderators
Posts: 8172
Joined: Fri Jul 04, 2008 1:01 pm
Bike owned: CBR954
Re: NC30 clutch issue

Post by Neosophist »

Springs come on all at once...

Strange explanation but you mean there is no slippage of the clutch? It's either engaged or disengaged.

Worn plates can do this as well as incorrect assembly, or both.

People put extra springs / plates in there.. i'm sure Mark will have some more info about this.. :)
xivlia wrote:i dont go fast on this bike so really do not need a rear brake.. /
vic-vtrvfr wrote:Ask xivlia for help, he's tackled just about every problem u could think of...
Smoky
Familiar Member
Posts: 263
Joined: Wed Sep 24, 2008 9:43 am
Bike owned: NC30
Location: Hackney. East London
Re: NC30 clutch issue

Post by Smoky »

Springs come on all at once...

Strange explanation but you mean there is no slippage of the clutch? It's either engaged or disengaged.
pretty much, yeah. to get a smooth pull off you need to be MEGA careful with the lever as the biting point is so narrow.

the plates that were removed were well past their day- two of the friction plates were almost smooth- but even then i could still get a decent biting point- just no full throttle as it would slip :-( hense the change...

cheers-
User avatar
CMSMJ1
Moderators
Moderators
Posts: 7161
Joined: Thu May 01, 2008 9:42 am
Bike owned: NC30-No9
Location: Chesterfield, United Kingdom
Re: NC30 clutch issue

Post by CMSMJ1 »

I reckon it has been installed incorrectly. How many springs you got fitted?

Does your mechanic know we have a thread on here about doing work that is substandard or ineffective!

We can email him a service manual??

Adding extra springs amkes the take up of the clutch very sharp and the cable pretty tough to pull.

I could imagine that with fewer springs it would work, but would be vague and I expect it would slip like crazy
IMPERATOR REX ANGLORUM

The V4 is the law..

NC30 - No9 - my old mate
Smoky
Familiar Member
Posts: 263
Joined: Wed Sep 24, 2008 9:43 am
Bike owned: NC30
Location: Hackney. East London
Re: NC30 clutch issue

Post by Smoky »

I reckon it has been installed incorrectly. How many springs you got fitted?
to be honest with you mate, im not sure :-( wasnt there the whole time the work was being done...
Does your mechanic know we have a thread on here about doing work that is substandard or ineffective!
lol, he will now....
We can email him a service manual??
im gonna take my haynes with me next time im there, but would you reccomend the service manual over the haynes?
Adding extra springs amkes the take up of the clutch very sharp and the cable pretty tough to pull.
I could imagine that with fewer springs it would work, but would be vague and I expect it would slip like crazy
the clucth take up is very sharp indeed. but the cable isnt noticeably tougher to pull in- its just feels as if the tension from the springs comes in all at once... whereas there was medium tension on the lever before the rebulit clutch (10mm freeplay then tension all the way to the bar) now it seems all lumped together...
theres no slipping now- have tested that throughly... i just wonder what the hell is going on with all the freeplay on the lever.
and i miss being able to pull off in first without sounding like i cant use a clutch :-(
sorry if my explanations are shite- just having a hard time trying to articulate all this lol.

thanks everyone for the help and advice, it is truly appreciated.
User avatar
CMSMJ1
Moderators
Moderators
Posts: 7161
Joined: Thu May 01, 2008 9:42 am
Bike owned: NC30-No9
Location: Chesterfield, United Kingdom
Re: NC30 clutch issue

Post by CMSMJ1 »

Why not fit a new clutch?

SOuds like something not right in the installation - loose main nut? Did you use a new one?

ref service manual - it is the lngua franca of garages..and IMO better than the haynes book of Lies
IMPERATOR REX ANGLORUM

The V4 is the law..

NC30 - No9 - my old mate

Post Reply