I'd say you need a cush somewhere, either in the basket or in the hub or both. Otherwise you'll start chipping gears and such...
Yeah, I get that. But instead of fixing a potential issue, is there any clutch baskets I can get that will work, and just remove the issue all together. I'm OK with getting a cush hub, or cush sprocket. I'd also like the clutch to feel a little more grabby, this one is kind of soft. But I will find out if it's the oil, I'm due for a change now.
I know some 510's have non-cush baskets, could buy a used one and see if it fits. My clutch feels plenty grabby, could be your oil. Was it ever run with something not rated for wet clutches?
I had this issue and fixed it about an year ago; since then I have made about 2000 miles. Some days ago, when I replaced the Woodruff key of the crankshaft, I noticed this play: When I fixed it, the last year, I brought the clutch basket to the mechanic, who broke the rivets and did the main work. I gave him some OEM cups and he made some others nearly as thin as the OEM. I don't know which ones have failed first, the OEM or his, but they've failed pretty soon! So, I think that now I should get thicker cups, but I am worried about the basket and its gear: could more resistant cups damage them? I read, on the first page of the thread, that Rough Rider hardened the case (I guess he meant the basket). I could ask the mechanic if he can do that.
Today I've brought the clutch to the mechanic and he's told me that the play could be caused by wear of the six rectangular holes which contain the springs, or of the three holes for the rivets; in fact, the cups seem to be still good and I haven't found debris in the oil like the last year. So, the next week he will brake the rivets and he will find out what's the problem. His cups are also cheaper than the OEM: here the dealer wants 104 € for the twelve cups, but my problem is that usually goods from the USA take about three weeks to come here in Italy and I'd like to enjoy the last hot days of the Summer. So if I need to replace them, I'll look for cups that I can get sooner. Anyway, thanks for the suggestion.
So i've been reading up on this topic....definitely sucks to hear! Now I have to check for another potential problem!! My question is, could you just use a large steel dowel/drift pin and lay a bead of weld on both sides? Then you don't have to worry about hammering the rivets. Or better yet, a large set screw. Tap the holes the right size and thread them in there. Then lay a bead of weld across them. Even more strength.
You're joining an aluminum basket to a steel gear and a steel back plate in a system that sees temperature cycles, I'd be afraid of annealing the back plate with a weld and having it fatigue and crack. Some have gone the screw/loctite route and I haven't heard of anything flying apart, you just have to use some low button heads.
Ahh....didn't even think about the clutch basket being aluminum. As long as you weld the steel right, you shouldn't have to worry about the back plate though....either way, you still have the aluminum clutch basket so threading and loctite would be the only way. I dunno, just an idea I thought of. Figured I'd ask.
The mechanic broke the rivets and he found out that the cups are ok, but they have worn out the six rectangular holes which contain the springs on the clutch housing: This is what caused the play I showed in the message #146. The replacement housing here costs about 330 €, but the complete clutch with housing, cups, springs and the 75t driven gear, plus the 32t driving gear of the crankshaft cost less: 313 €. I prefer to fix my clutch: the mechanic can make six cups (one for each pair) shaped like this, to eliminate the play: I’d also like to harden the housing; the mechanic suggested the “ossido duro”, that’s a thick anodization, I think. So, I asked a company some information and they told me that I can do it for less than 100 €, but the thickness of the treatment is about 30 micron. So, I’m wondering if that additional thickness could create problems in the points coupled with other parts, like these: What do you think about it? They told me that they can create a little nylon frame to cover those points and prevent them from being anodized, but then the price would rise very much. The discs already have a rotational play with the housing, measuring about 0.70 mm, so 30 micron should not be a problem, but maybe an harder housing could damage them, in my humble opinion. Besides, the points under the discs tongues would press them a little, because of the imperceptibly increased height of the housing, so I think that those points should not be hardened.
30 Microns is barely one thousandth of an inch, I think you'll be just fine without masking. I'm not familiar with that particular coating if it's not a standard type of anodizing.
Unfortunately, I don’t know much about anodization and so I don’t know exactly what treatment it is and how to translate its name into English. I know that 30 microns are very few, but I’ve measured some dimensions, using a caliper whose sensitivity is 0.05 mm: My aim was to find out if a fraction of a millimeter matters in this situation. Probably the little differences of the central hole measurements are due to my lack of accuracy, because it was difficult to find the maximum inner diameter in every position. So, I’m afraid that 0,05 mm, i.e. 50 microns, matter. Maybe there would be enough clearance to reassemble everything, but I'm not sure. Anyway, I've found another company that maybe could harden it without dimensional modification. I'll ask them if they can do it and how much it would cost.
Why go to the trouble to harden an already worn and compromised part? IMHO rather buy a new one or good used one and have it done if you feel the necessity. I find it strange that the cups were OK ?! Were they by any chance replaced before with the hardened ones? This may explain the wear on the housing.
Because a new clutch housing costs more than 300 €, so I'd like to try to reuse the one I already have and harden it to stop the wearing. Maybe the idea of a good used one is not bad, but it could be worn by the discs in other zones: how can I be sure that it isn't, without checking the clearance with a feeler gauge? Yes, you're right: they were replaced with thicker ones about 1,500 miles ago, but I don't think that they were hardened.
To be honest, I don't really see any benefit at all getting the basket anodized, after all, it will still be much softer than the steel that will be wearing against it, unless that coating may be a millimeter or two thick, in that case the anodized layer would be much too brittle... You would be better off saving your money and getting a good second hand one.
I’ve contacted them and they’ve told me that the treatment doesn’t modify the dimensions because there is something that infiltrates in the part and harden it. Unfortunately, it works only with a specific aluminium alloy and the only way to know what alloy is the one of the clutch is to try the treatment, but if it fails, the part will be damaged. The Husqvarna seat in Italy has been closed, so I can’t phone them any more to know the alloy. Besides, they've seen a photo and don't think that it would work on that material. So, I went to the mechanic to get it reassembled with the modified cups I’ve shown, without any treatment, but we noticed that the only zone of the part which needs a great dimensional precision is the central hole, the one measuring about 62 mm in the picture I posted. The three circular pieces measuring 18.15 mm have a bit of clearance in their seats in the 75 t clutch gear and, looking better, it seems that the last disc doesn’t touch the clutch housing in its bottom area. Now I intend to make them treat the part with the process which adds 30 microns, after having created a circular piece of insulating material to embed in the hole, preventing its surface from being treated. That company provides eleven different treatments for aluminium alloys and I don’t know what they are, but I’m not sure that they are all anodizations; the one I mentioned, without dimensional modification, is not a standard anodization. The mechanic told me that an anodization wouldn’t be useful, so I don’t think that the treatment he suggested is it, but using the Internet I haven’t understood the difference between “anodization” and “ossido duro”, which could be translated –I think- “thick oxidation”, or maybe “hard oxidation”. Is the hard oxidation a thick anodic oxidation, i.e. a thick anodization?
If it's similar to a type III mil-spec hard anodizing similar to what's used on aluminum firearm parts like AR15 receivers, it'll add a bit of wear resistance, but it won't hold up forever. Personally, I've got 12K miles on my SMS, and other than smoothing out the fingers with a fine file and replacing the bronze bushing, the clutch and basket are all original and show very little wear. Just ordered a Kush sprocket to take even more shock out of the system and prolong the gear life.
Have you tried various places around the world? There are a few dealers here: http://www.cafehusky.com/pages/chsponsors/
