400 Clutch de-glazing (Again)

[Chilly]

I know there's lots of bits and pieces on here and other sites about it. But, I can't find 'start-to-finish' instructions on how to do the whole job.
Can anyone point me to a definitive guide please, whether on here, other burger sites or You Tube.
Ta in advance, Chris

[bornagainbiker]

Hi Chris. Check out Mitch's Scooter Stuff (PS he is deaf)

[Chilly]

Thanks. I've looked down the playlist but I can't see any about deglazing the clutch. Or am I missing something?

[Data]

Hi Chilly, so you have the dreaded clutch judder no doubt? Understand that regular clutch maintenance is a requirement on all dry cvt clutches regardless of the bike. But the bike should go for many thousands of miles before it needs to be done. Ok so here below at the end of this post is a rough guide I posted sometime ago on burgmanusa about dealing with the deglazing and cleaning of the clutch. I may have done the same here too but can't remember. Since I originally posted about the judder and remedy, I've learned and written a lot more about it. I discovered something else too that is very important in preventing the early return of the problem. I now service four other Burgman 400's on a regular basis and two of them had the judder which returned early after the owners had tried to cure it themselves, and the owners were, like me, doing something wrong when they did the fix. I noted they both, like mine, had slightly uneven clutch shoe surfaces. It was I stress only very very slight and hardly noticeable until you looked hard. The glaze was uneven on the shoes which was the give away. The shoes must be kept completely flat in the cross plain with no uneveness at all.

If you get the shudder/judder come back after having fixed it once already, then when you deglazed it last time you may not have done the job correctly in the first instance. THE KEY FACTOR is to keep the clutch shoes level in the cross plain when you deglaze them. If not the uneven take up of the drive causes problems by allowing clutch dust to collect in the slight indentation on the surface of the shoes. This causes dust and resin to build up in the depressions which when released causes sticking and judder. This in turn causes more localised heat and damages the inside of the bell causing grooves. Hard to believe I know but I've put a lot into this and I'm certain this is the problem.

So make sure you use a SMALL sanding block when you do the deglaze and use 80 or 100 grit emery paper. Don't use anything other than 80 or 100. It won't do the job properly. DO NOT USE YOUR FINGERS ON THE ABRASIVE PAPER TO RUB THE CLUTCH SHOES, as this will introduce the slight uneveness to the surface of the shoes. It will be there and you won't see it. The shoes are quite soft and easy to damage like that. So with a small block rub lightly in purposeful strokes from end to end of the shoe. You must expose the clean fibres, and do not breath the dust that's produced. Suzuki warn in the owners manual there may be asbestos in some parts of the bike. Maintain the radius of each shoe by not rubbing in one place, just use the long even strokes. You want the surfaces to be even and clean with a slight roughness to them. Make sure to chamfer the leading and trailing edges of the clutch shoes and treat each clutch shoe to the same number of cleaning strokes to keep them in balance. Use emery paper or better still, cloth, to reduce any fall out of abrasive particles into the clutch area if you are not removing the clutch to do this (you don't need to). Sandpaper will drop loads of abrasive particles so don't use it. Remember to clean out the clutch bell with brake clean and roughen the drive surface slightly.

Doing it this way has completely cured my own judder and that of the two individuals whose bikes I service. Checking the clutches on all of our bikes has shown the shoes to be completely flat (like the world!!) although of course some glaze is present and that's normal for any dry clutch and nothing to be concerned about. We have all done loads of miles since it was done last with no re-occurance of the trouble. These days my bike does lots of traffic work in towns and still no return of the problem judder. It's been over 10k miles since mine was done. Some might have to do it earlier and some may be able to leave it until 14.5k miles when the final drive oil will be changed again. That's the ideal time to do the clutch thing again. I've since recommended this technique to others and they too have had no more problems. Of course the other thing is to make sure you get your moving off technique correct. Use plenty of revs (4k plus) and feed in the power as you move off, back off the throttle a little as the clutch locks up to control speed. This reduces slip time for the clutch and reduces dust and heat. You may still get the odd infrequent shudder which will always go away but you won't suffer the judder if you do these things. Good luck bud. One other important point. MAKE SURE TO CLEAN THE TRANSMISSION AIR FILTER EVERY 1800 MILES AS PER THE BOOK. This lets maximum clean cool air into the transmission case to cool the belt, clutch etc and clear the dust out of the tranny air outlet. Here's my link, I'm Quantum Mechanic on that site. There are some photo's that you won't see unless you are logged into that site:

http://burgmanusa.com/forums/52-burgman ... tch-2.html

Bye for now. (sorry for the rambling nature of my post/s)

[who-me]

Just saying but I had bad clutch judder on my L1 400 7500 miles or what I took to be clutch juder it was not pleasant on take of at all , and all I did was change the rollers and its now like silk , so I wonder could the judder be caused by the way inwhich the variator drives the belt to the clutch , all I can say it worked for me !

John

[Data]

Hi who-me. If you had geniune clutch judder the rollers would not affect it par se. But may have affected the speed at which the drive started to take up. Which may have helped. Generally speaking though the rollers are not the cause of clutch judder. Glad yours is ok.