Bad clutch basket? Symptoms? How many miles do you have?

[Cortez]

I was just infomed by my mech that my clutch basket should be replaced.
My bike has 26k miles of smooth riding, clutch was never dumped to pop a wheelie etc.
Last bike that I got up to that mileage had clutch "as new" (as possible) when inspected (a ninja 650r).

The reason I brought the bike into the shop was worsening of the on-off throttle smoothness/jolting
back and forward as if the bike's fueling was getting worse with mileage.

It's like there is a slight hesitance when applying the throttle.. a dead/flat spot where the bike would
usually smoothly pick up (regardless of the rev range) that but then it would suddenly grab a lot more
aggressive. I learned with time to get around that by being a lot smoother and clutching it a lot more.

Riding fast at high revs in the twisties for example it would be extra bad getting back on the throttle after
a corner. Another symptom is like there's some slack in the drive train (like a badly adjusted chain) and
when that slack goes away after a metalic thump the bike jolts forward much faster then expected.

I figured throttle body sync, clean the injectors and it should be good (this is being done as we speak tho).. since
my MPG figures were getting worse as time went by too. The exhaust note also has some crackling and popping that's
been going on for about 6k miles, depending on the weather/temperature.. (stock exhaust). I wouldn't say there's
any surging when the bike is on constant throttle but it's like it's not running smooth with a constant "zzzzzzzzz"
engine note as before.

Anyways, we'll see what's better and what's not when I get the bike back, I can't afford to replace the clutch basket
and the repair guy says I can do thousands of miles with the basket in this condition too.

Anyways.. I guess my question is - what are the main symptoms of a bad clutch basket and when did you replace yours (if at all)?

p.s. The gearbox shifts fine, it was never smooth, a bit of throttle helps but it was like that since day one.

 

[TownsendsFJR1300]

I'd like to know specifically, what he found wrong with the basket. If you could ask, please.

IE, notches in the fingers of the outer basket, looseness between that basket and the large gear attached behind it, etc.

I believe the noise, on/off throttle, poor mileage are two separate issues.

 

[Cortez]

I'd like to know specifically, what he found wrong with the basket. If you could ask, please.

IE, notches in the fingers of the outer basket, looseness between that basket and the large gear attached behind it, etc.

I believe the noise, on/off throttle, poor mileage are two separate issues.

I'll be picking the bike up in an hour so I'll try to get a better answer.
Yes, the mileage should be down to sync, dirty injectors and some other stuff, that's not as important right now.

The CLICK/thud before the bike would engage or disengage when on or off throttle was thought to maybe be loose
front sprocket, but he checked and said it was fine. It's literally the same feeling as a loose chain. Can THAT be
because of the clutch basket? If I was to gently clutch it before applying the throttle I could avoid the *thud*. I can still
usually hear it but CAN clutch it gently enough to be able to shift very smoothly and/or get on the throttle very smoothly
by slipping it a bit.

He just said he sees normal wear for that mileage and that getting this "slack" out of the whole transmission system
would cost a lot and he wouldn't worry about it or do it if he was the owner.

 

[FinalImpact]

If the valves need adjusted, this can add to the harshness of the chop. The valve lash being off on even a single valve of the four cylinders impacts cylinder pressure, engine vacuum, and overall smoothness of power delivery.

Honestly Id save your money as it will not be a night and day fix that solves your issues.

Any mods to the exhaust?
TB syns should find a vacuum leak but if its small enough it may go unnoticed.

Your goal at this time is to find out its burning more petrol as that is likely a symptom that is making this worse.

Poor grade of petrol.
Dirty air filter.
Worn, excessive spark plug gap, dirty plugs.
Valve lash off
Vacuum leak
Engine oil breaking down.
Chain conditon. To dry and hurts performance.

Those come to mind as far as fuel economy.

Chain, clutch and throttle all being properly lubed and adjusted can decrease transitional impacts of harsness...

Question, if up at say 6000 rpm, do you still notice this chop/harshness?

 

[TownsendsFJR1300]

The clutch basket itself seems to be pretty reliable with VERY FEW if any failures that I've seen here in 8 years.

Your mileage is nothing if the bike was maintained and especially if not abused..

From pic's I've seen here(I never had my clutch out/apart), it appears there's 3 large rivets holding the basket to the large gear on the back.
If those loosened up for some reason, that would make a bit of noise and feel as that connects the engine to the gear box. It could potentially
be banging back and forth with the throttle / load..

 

[FinalImpact]

Even the mechanic said it was waste throwing a basket at it...

FWIW I have thread devoted towards correcting throttle chop. These will never be as smooth as a carbed bike, but with a couple of engine mods, you can make it near invisible...
Proper fueling from fuel controller.
Free flowing exhaust.
Advance ignition timing and its gone....

Very happy w the mods as it also pulls very well!


Edit: almost 26K miles.
Only hardware replaced was rear sprocket and that was for a gear change.
Clutch and basket are solid. No issues.