Worn fork yoke stem (2015)
- Thread starter mkv750
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- Jan 8, 2014
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I have been thinking of JB weld Hobot, the wear/clearance is not that great, I think you are right on the locktite, not the application for it here.
Thanks LAB, I am sure there are no numbers, but will double check when in the workshop next.
Gripper, I brought the bearings from RGM, they are a very nice fit to the top of the yoke stem, so the wear is in the lower stem, how it came to wear there, no idea, perhaps in a past life, the yokes/stem were stored off the bike, or rather in this case it seems they are later yokes anyway, from another bike, maybe they got a bit rusty, a previous owner might have cleaned them off using abrasives and ended up putting the wear onto the stem in the process?, a thought...
John
Thanks LAB, I am sure there are no numbers, but will double check when in the workshop next.
Gripper, I brought the bearings from RGM, they are a very nice fit to the top of the yoke stem, so the wear is in the lower stem, how it came to wear there, no idea, perhaps in a past life, the yokes/stem were stored off the bike, or rather in this case it seems they are later yokes anyway, from another bike, maybe they got a bit rusty, a previous owner might have cleaned them off using abrasives and ended up putting the wear onto the stem in the process?, a thought...
John
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- Oct 19, 2005
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JBW does is not much an adhesive on smooth surfaces and gets its grip by locking into surface texture so I'd scuff up the stem some but no shear forces so not much texture needed. Also JBW is brittle in thin layer so I'd work some dry link fibers in the mix to make it semi fiberglass. hobot lazy way would be wipe wax/light oil-grease inner race and yoke or what ever excess might stick to with even masking tape to catch drips then slip bearing over JBW smeared stem held level/vertical, wipe up excess and let set up, slip off bearing, hand sand clean up some and go ride on it. If goof up just bench wire brush mostly off and try again. If ya put magnet on stem the JBW will be attracted to stem unless magnets too close then can crawl up hill out of the gap.
mkv750 said:
No need to measure anything, its recorded in the factory specs for the ANG yokes that the tubes point 'backwards' in those yokes by a few degrees.
If you run the bottom yoke up against the top yoke, you can readily SEE that the top yoke juts forward a bit.
So the tubes for ALL disc braked bikes (with the ANG yokes) have to point 'backwards', only by a shade though.
Incidentally, I pointed this out on the NOC group some years back now, and a common reply was "your yokes must have been in an accident" !!
Guess that sums up the NOC in a nutshell....
BTW, I suggested earlier that your stem could be lightly knurled where the bearing is a loose fit.
This is not an entirely acceptable engineering practice, but its light years ahead of JB weld etc - sheesh.
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- Oct 19, 2005
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Kind of frustrating just reporting facts that arn't believed. Knurling saved Peel from JBW on pistons and seems more desirable bodge than epoxy on stem if trying to save it. Issue would be finding show set up to do kurling and also figure out how to hold stem if yoke still attached.
hobot said:
Run a shaft up the centre of the stem, and chuck that in the lathe ?
Reinforces and strenthens the stem for knurling too...
Visions of pistons coated in JB Weld swim before my eyes.
Glad we didn't have to read the post mortem on that one.... !
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- Jan 8, 2014
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Well, that was easy!,
I got a new stem from RGM, thanks for the offer Kommando, but seeing as I wanted some parts from RGM, it seemed easiest to order the stem from them, it was about £22, so not bad at all.
I placed the yoke on the old Anvil, over the hardy hole, one good hit with a heavy hammer on the threaded end of the stem, it moved about an eighth of an inch, couple more hits and the old stem was out!, I think the anvil helped a lot here, a solid base, with no give what so ever, so the hammer blows were transmitted in their full.
I used the old circlip, fitted in a groove at the top end of the stem, stops it from being pulled through the top yoke, RGM did supply a circlip, but it was too small, I think from what the chap said on the phone, they did not have one listed, so he said he would have a look see, and send one if he could, it would of done, at a pinch, he did say he thought I would be able to use the old circlip, or is it called a snap ring?, which in this case I did re use it.
So, the new stem went back in, threaded end first, through the top of the yoke, slid down until the knurled section of the new stem met the yoke, a bit of locktite, back onto the anvil, stem through the hardy hole, an old socket as a drift, a few good taps with the heavy hammer, being careful to listen for the circlip/snap ring to seat, and all done!, very easy.
I did have a good look, used a small screwdriver, to make sure the circlip/snap ring was seated nicely.
The RGM stem is a little thinner in the walls than the old one, but very happy with it, maybe the slightest "play" when fitted to head, but I have not tightened it down yet, so might well being a little sensitive there.
Thanks to all who posted, very helpful, thank you for the photo of the ANG yokes, Rohan, but do not worry about the JBW, I was actually thinking of it being used in conjunction with the knurling, just to add surface area, with the knurling doing the supporting.
OK, now for fitting the RGM covenant damper improvement kit to the forks, then the front end can go back together again.
Then for the next job.......
John
I got a new stem from RGM, thanks for the offer Kommando, but seeing as I wanted some parts from RGM, it seemed easiest to order the stem from them, it was about £22, so not bad at all.
I placed the yoke on the old Anvil, over the hardy hole, one good hit with a heavy hammer on the threaded end of the stem, it moved about an eighth of an inch, couple more hits and the old stem was out!, I think the anvil helped a lot here, a solid base, with no give what so ever, so the hammer blows were transmitted in their full.
I used the old circlip, fitted in a groove at the top end of the stem, stops it from being pulled through the top yoke, RGM did supply a circlip, but it was too small, I think from what the chap said on the phone, they did not have one listed, so he said he would have a look see, and send one if he could, it would of done, at a pinch, he did say he thought I would be able to use the old circlip, or is it called a snap ring?, which in this case I did re use it.
So, the new stem went back in, threaded end first, through the top of the yoke, slid down until the knurled section of the new stem met the yoke, a bit of locktite, back onto the anvil, stem through the hardy hole, an old socket as a drift, a few good taps with the heavy hammer, being careful to listen for the circlip/snap ring to seat, and all done!, very easy.
I did have a good look, used a small screwdriver, to make sure the circlip/snap ring was seated nicely.
The RGM stem is a little thinner in the walls than the old one, but very happy with it, maybe the slightest "play" when fitted to head, but I have not tightened it down yet, so might well being a little sensitive there.
Thanks to all who posted, very helpful, thank you for the photo of the ANG yokes, Rohan, but do not worry about the JBW, I was actually thinking of it being used in conjunction with the knurling, just to add surface area, with the knurling doing the supporting.
OK, now for fitting the RGM covenant damper improvement kit to the forks, then the front end can go back together again.
Then for the next job.......
John
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- Sep 26, 2009
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RGM damper improvement, forget it! I would replace the internals with something that works. :roll: Knocking in bits of pegs and redrilling...Ok give us the lowdown.
mkv750 said:
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- Sep 4, 2009
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So what is available for a cartridge damper now that Lansdowne is out?
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- Jan 15, 2019
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Dear John, thanks for this since I have to do the same thing with a top yoke. My old man grinded off the yoke since he fitted clip-ons. I want a high bar mounted so have to replace the top yoke.
Contrary to what I was informed the stem goes out upwards then so to speak.
Since you say I hammered on the treaded side, this is wear you normaly have the nut under the bottom yoke..
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