https://threebond-europe.com/products/tb1327/ we prefer 277Well folks, here's a conundrum. Early bike, no evidence that it's been apart before. I wanted to put my mind at rest, so stripped the primary to inspect and look what I found....
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Yep, the "rivets" are already welded, plus the shock springs have top hats in them.
I found both of the 6205 bearings loose in the housing and there are signs on the inner that the track has been spinning in the basket. That bearing is a bit grumbly but not too bad. They'll both be replaced. There is a large circlip between the bearing to locate the clutch basket and a spacer shim which is supposed to stop the bearing centres pinching up when tightened. That spacer was thicker that the circlip so I've skimmed a bit off it to match, so the outers should be held securely in place and the bearings can control the end float.
Ring gear nice and tight, no signs of any movement, but I will pin it anyway.
A question - In the manual it says to use Threebond 1327 on the shaft nuts etc., but I cannot find it anywhere (even on the Threebond catalogue) does anybody know what it been superceded with? Or would Loctite 243 do the job as well?
Thanks for the link & tip !
Thanks for the link & tip !
The spacer is supposed to be thicker than the circlip. This is so that the clamping pressure of the shaft nut is applied to the inner race of the bearing , not the outer !! Being thinner will now put severe load into the spheres of the bearing and it will fail.Well folks, here's a conundrum. Early bike, no evidence that it's been apart before. I wanted to put my mind at rest, so stripped the primary to inspect and look what I found....
View attachment 82055
View attachment 82056
View attachment 82057
View attachment 82058
View attachment 82059
Yep, the "rivets" are already welded, plus the shock springs have top hats in them.
I found both of the 6205 bearings loose in the housing and there are signs on the inner that the track has been spinning in the basket. That bearing is a bit grumbly but not too bad. They'll both be replaced. There is a large circlip between the bearing to locate the clutch basket and a spacer shim which is supposed to stop the bearing centres pinching up when tightened. That spacer was thicker that the circlip so I've skimmed a bit off it to match, so the outers should be held securely in place and the bearings can control the end float.
Ring gear nice and tight, no signs of any movement, but I will pin it anyway.
A question - In the manual it says to use Threebond 1327 on the shaft nuts etc., but I cannot find it anywhere (even on the Threebond catalogue) does anybody know what it been superceded with? Or would Loctite 243 do the job as well?
The 6205 bearings are a standard 'off the shelf' bearing. If I remember correctly they should be FAG6205. I don't recall them being C3 grade though. The C3 has a greater clearance between the sphere and the race groove, and would as a result lead to the clutch 'waggling' around its axis. Considering that the gear teeth are a very basic straight cut form, then this would generate considerable noise. Hence why nearly all road bikes use helical cut gears.Hi NikolI, if the spacer and the circlip are the same thickness, why would it put any load on the the bearings? surely the only load on them is axial?
I understand What you’re saying about the clamping force of the rivets, but I cannot feel any play. What would you suggest I do?
Yes it does. I've measured itThe extra clearance from two C3 bearings next to each other would be negligible and not increase clutch wobble much if at all, completely different for a single bearing where a CN or C2 would be needed. CN to C3 is a change of microns in internal clearance and at 15mm apart centre of ball path to ball path significantly reduced in external effect.
A long time ago, one of the Norton engineers called 'Paul' actually looked at the roller option in a bid to try and help reduce the gear mesh noise. It was at this time when we compared the standard bearing to the C3, and measured the deflection. The values I can't remember as it was around 2009 I think. He discovered a roller bearing with a thrust face option, but he left the business before he had a chance to trial it. Some crank shafts use the ball and roller combined method , so It could be worth persuing, but is it really a problem that requires solving to that extent ?Thanks for the feedback. I can confirm the bearing are indeed FAG 6205, and are C3 spec. Do you think they need to be? Like you say there was a bit of "waggle" and the inner race is a bit rough with evidence that it had been spinning in the basket, hence my thinking of reducing the spacer to make it more like one double row bearing, but if you think that's not a good idea I can easily knock up a thicker one.
I did ask earlier in the thread about using a roller, but obviously end float control is an issue. Do you think a roller on the inner and a ball on the outer would work ?
Thanks, I'll look into it.As popular as the 6205 is , there may be a option of oversize OD +.002. Little known but their out there