A bit of help needed here folks. With the bike idling in neutral there is a constant chattering sound almost like slightly loose tappets if that makes any sense and when you pull the clutch lever in the noise disappears. Unfortunately over the last couple of days when the clutch lever is pulled in there is what can best be described as a faint whistling noise which rises to a squeal when the engine revs are increased eg pulling away. I am guessing the culprit is the Clutch release bearing but I have been looking at the downloadable manual for the 750 Breva (oops should have mentioned that was the bike) and I cant find any reference to or pictures of it or where it might be located. Looks like the clutch is behind the flywheel unlike rear wheel drive cars I have worked on where once the gearbox was off there it was. I would like to tackle the job myself bu tit would appear not to be for the faint hearted, especially if special tools are needed. All advice greatfully received.
It is in the back of the gearbox, you should see an arm that is pulled by the cable, the bearing is just behind that. Swing arm out job to replace it, Once that is out of the way it should be a 5 min job to swap it over.
That’s a relief. I thought I would have to take the gearbox and clutch out. Would I be correct in thinking its behind the rubber cover the lever sits over? If I take the old one to a bearing factors I assume they would be able to match it up and I’ll be back in business. Many thanks, very much appreciated.
I have not been in the small block mechanism, but the big ones have a radial needle bearing. Not sure of any rubber cover, but the Breva is a lot newer than the bikes I have knowledge of.
If it is like that and albeit it can be greased on assembly (I was going to suggest may not have been greased at the factory) BUT it’s also lubricated from the other side by gearbox oil.
The ‘chattering’ may be nowt to do with it, this has been mentioned before on a modern model? Anybody? And it’s ‘normal’ ?
I think the chattering has probably always been there since I have had the bike so for the last 5000 miles of the 13000 it has covered. It’s the noise when I pull the clutch lever in that is bothering me. Bottom line I guess is once the swing arm is off will I be able to get the bearing out or is it fitted from inside the gearbox.
Anyone reckon that the centre has pulled out of a clutch plate ? Has happened to the G5 a few times over the years. Maybe as the question was about thrust bearings he may be thinking that the clutch works like a car. The radial bearings wouldn’t make any noise as I am pretty sure they aren’t spinning.
Love and kisses
You’re right I did think the clutch works like a car one. Whistling/squealing noise only occurs when clutch lever pulled in. Bike still drives in all gears ok.
The radial needle roller bearing Don mentions is in the back of the gearbox. It’s underneath what looks like the rod that the gearbox clutch arm pushes on. This has a larger diameter part within the gearbox cover (‘T’ shape in cross section), then a washer, the needle roller bearing then another washer, then another ‘T’ section bit which in turn in mounted on the back end of the clutch pushrod. This goes right through the input shaft (which is hollow) and thence presses against a thrust piece in the centre of the flywheel pressure plate. Which is in front of the clutch plates actually.
Anyway bottom line is you should be able to hook the needle bearing out after removing swing arm and gearbox clutch lever.
Many thanks to everyone who has replied to this topic especially Martin who sent me a pm. Hopefully the problem is not as dire as I had thought and I should be able to sort it with out resorting to having the gearbox out. The prospect of having my bike spread round my mates garage 40 miles away while I had to travel back and forth to do the work and no doubt wait for some elusive part (my rear brake master cylinder springs to mind) to make it over from darkest Europe filled me with dread.
Been there done that got the T-shirt!
Does become a pain after a while. Though my mate was only 5 miles away.
did the rear bearing on mine last weekend, no need to remove box or crab frameword of warning, make sure the inner pushrod adapter goes in dead square and over the push rod or you will have fun getting it back outbearing needs a touch of moly type grease on it, replace the washers that sit each side of the bearinggot mine from gutsibits
I’ve ordered mine from Gutsibits and they’re going to send it with the rear brake master cylinder when that comes in.
That sounds like the voice of experience.
Oh yes. Tell you next time I see you at Ray’s…!
If you mean what I think it is, you may be lucky where it’s a bit tight on the rod.
My Breva 750 has an intermittent squeal once it’s well warmed up so I’m following this with interest. One thing I’m not sure about is whether this bearing is covered by gearbox oil or just gets a splash feed, can anybody enlighten me?As well as this, there are mentions on a few forums including here, of putting moly grease on it, if it’s getting oil on it will this actually do anything?And finally, I’ve read somewhere, and can’t find it again, that somebody fixed it in 30 mins with a squirt of copper grease,that sounds good if it actually works.Like I said, I’m following and eager to learn!Regards,John
rear bearing is fairly easy to change, but can cause some catastrophic damage if it fails… I speak from recent experiance
Also making sure the inner cup is seated over the pushrod is a little tricky, if you miss it take a very strong magnet to get the bl00dy cup back out…
there are 2 types of push rod , a standard one and a later upgraded on with small spiral machined into the rear end to get some lubrication into the end of the rod and rear cup
This is the later v7 type push rod
My rear bearing had done a genuine unlubricated by Luigi 6000 miles from new and destroyed its self and one of the facing washers… When it let go 2 weeks a go it locked the inner cup and push rod solid… The engine end of the push rod went molten and splattered its self over the clutch and fly wheel
Push rod on the left nicely melted and about 5mm shorter, the mush room end matches whats left of the old clutch center
I now have a later pre - assembled v7 clutch with slash cut clutch plate and spiral type push rod .
Rear bearing + rear cup + spiral lubed with moly grease prior to fitting
Clutch lovely and light and bites just right
All the small blocks have the same clutch and parts are interchangable. My 1977 v35 hybrid now has a v7 classic clutchguzzi-v352014-08-09 20:04:26
Mild compared to what I said when molten metal came out of timing hole