Gearbox/clutch issue

[the_names_james]

I've tried searching but can't seem to find anything relating to my problem.

Forgive me if this ends up a little drawn out...

I took the bike out for a ride last night and when I was almost home the gear selector started acting up; I was having to practically stamp on the lever to get it to downshift and it was fairly difficult to find neutral (she kept jumping from 1st straight to 2nd and vice-versa). The clutch lever had roughly half inch of play too. It was dark so I figured I'd take a look this evening.

I also happened to have a 14t front sprocket arrive today so figured I'd swap that while I was there (chain+rear have covered approx. 800 miles so I didn't bother with those). I removed the sprocket cover and immediately noticed the clutch linkage 10mm's were loose. I tightened them, checked the lever/shifter and it felt like the issue was fixed. Then I removed the linkage to access the nut, straightened the washer and struggled like crazy to get the sprocket nut undone. Eventually I resorted to a 3' breaker bar with an 8' scaffold tube and still nothing so I'm guessing it was waaay over tightened when the chain was replaced.

So eventually I gave up for tonight as I was worried something else was going to break before the nut came loose. Put everything back together, fired her up, engaged first, clutch out and nothing... Back into neutral, click into second, clutch out and still nothing...

Anyone have any ideas as to the problem? The bike has covered roughly 1500 miles since its last oil change. And is there a trick to loosening an over-tightened sprocket nut? I don't want to heat it if I can help it.

Thanks in advance.

[Sid Squid]

If you've got an SV* adjust the clutch:

Slacken off cable adjusters at top and bottom, loosen lifter locknut, back out screw a bit, ensure that lifter arm is as far down as it will go, gently turn screw in until it contacts pushrod, back it out a bit, (~1/8th of a turn), then nip up the locknut, roughly adjust cable with lower adjuster - not too tight - then with top adjuster ensure that there remains a little slack all the way from lock to lock.

When you tightened the bolts holding the lifter you have effectively lifted the clutch.

*It would help to know exactly what bike you have.

[wideguy]

Impact wrenches, either pneumatic or electric is what I'd try for the sprocket nut.

[the_names_james]

Sorry I should have said; I have a K8 SV650S.

The bolts I referred to are the two 10mm's holding the linkage to the casing (here: http://i.imgur.com/YrKwIXG.jpg) or is that what you meant?

And I've tried my impact gun (Ingersoll Rand not some cheap pos) on it, the nut just doesn't want to budge. I'll speak to my Snap On dealer and see if he'll let me 'demo' their top gun for a couple of days.

[wideguy]

There is a tab washer to lock the sprocket nut, but I'm sure you bent it out of the way- hard to get a socket on otherwise. I'm looking at 105 ft.lb. of torque on that nut? With a little rust in there, it could be a bugger. Try soaking it overnight with some of your favorite penetrating oil?

[the_names_james]

I bent the washer before attempting to undo the nut. I'll give it a good soaking with WD and see what happens.

Tbh the clutch is the priority right now.

[Biker Biggles]

That bit you tightened up is the clutch adjuster mechanism.You need to start there and ensure it is set up correctly before anything else or it will never work.You may have another problem too,but you wont be able to fix it until that worm drive system is correct.

[the_names_james]

Turns out it adjustment of the clutch actuator mechanism was required, exactly as Sid suggested.

And Snap On's impact wrench had no trouble with the nut.

Thanks to everyone who contributed :)