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#1 Needle bearing for clutch fork shaft?

Posted: Sat Aug 16, 2025 11:54 am
by Philippe-J.
Hi!

dismantling my clutch (and gearbox) I discovered that the 2 brackets holding the fork shaft are equiped with sort of needle bearings:
Image
I can't find them in the documents.
Do you have any idea about their references, so that I can purchase 2 of those and replace my originals?
Thanks in advance.

#2 Re: Needle bearing for clutch fork shaft?

Posted: Sat Aug 16, 2025 12:03 pm
by mgcjag
C10025...they are bushes not needle bearings...Steve..ps you may have to ream the inside to fit your shaft if you replace them

#3 Re: Needle bearing for clutch fork shaft?

Posted: Sat Aug 16, 2025 6:23 pm
by Philippe-J.
Thank you Steve, perfect and accurate answer & remark.
Philippe

#4 Re: Needle bearing for clutch fork shaft?

Posted: Sat Aug 16, 2025 7:28 pm
by rfs1957
Philippe, your case looks like it has been bead-blasted, and if your bushings are indeed of a sintered semi-porous materiel then you need to be very careful that the beads (and their inevitable associated powder) have not inveigled (good word, beat that in French) their way into the stuff, as anything that remains will be highly abrasive on the shaft. Lots of cleaning in perspective.

#5 Re: Needle bearing for clutch fork shaft?

Posted: Sun Aug 17, 2025 7:11 am
by Philippe-J.
Good point Rory. Yes I did bead blasted the interior of the casing, as it was all covered with thick dirt.
So yes lots of cleaning is in order. Your remark is another reason for changing the bushes, isn't it?
BTW, do you agree with the idea of painting this interior with that orange "engine interior" paint, so as to avoid porous aspect, and consequences, of the alloy?
As for the french translation for "inveigled"... :scratchheadyellow: ... Maybe "tapé l'incruste", as for non authorized persons in a party?

#6 Re: Needle bearing for clutch fork shaft?

Posted: Sun Aug 17, 2025 5:57 pm
by Philippe-J.
Rory,

I think your advise was better than you thought, about the gear box that is.
As a matter of fact I bead blasted its casing too, to get rid of an awful red (Ferrari red!) paint. I tried and protect the interior from bead ingress, but you pushed me to carefully check.
What I mess I found!
A deep cleaning has started, but you can imagine how sticky a grease+dirts+fine sand compound can be :thumbdown:
But I'd rather do it before disaster occurs :shrug:

#7 Re: Needle bearing for clutch fork shaft?

Posted: Sun Aug 17, 2025 6:03 pm
by mgcjag
You got blast media in the gearbox?... there are lots of needle roller bearings in there....I think that a total strip down is the only way clean it all out....Steve

#8 Re: Needle bearing for clutch fork shaft?

Posted: Mon Aug 18, 2025 1:53 am
by angelw
Hello Philippe,
For future reference, if you want to inhibit the ingress of blasting media, of any bore like feature, seal it with Plasticine. One may think that such soft material would be ripped out in quick fashion by the blasting media, but no, you can direct the media blast directly on the Plasticine for some considerable time, and it will remain unscathed.

When you have a relatively soft material, of the bearing, and the relative hard material of the steel shaft, you have in affect, the making of a lap. In a lapping operation, you have a soft and hard component, where the hard material part is the component to be sized by lapping. The abrasive embeds in the soft material and wears the hard material that doesn't retain the abrasive. Accordingly, if abrasive material contaminates the bearings, it will embed in the bearing surface and wear the shaft in quick order.

As a beside, there is lapping media that can be used in an assembly, where it is abrasive for a finite amount of time. Accordingly, it can be added to the assembly to be lapped with no requirement to dismantle and thoroughly clean the component parts after lapping.

Regards,

Bill

#9 Re: Needle bearing for clutch fork shaft?

Posted: Mon Aug 18, 2025 8:36 am
by Philippe-J.
Thank you Bill for your advice, I'll buy some plasticine for next time. I guess I should make large covers for the apertures too, and fix them with plasticine.
Steve: yes, I started a complete strip down anyway, as I wanted to check every components of the gear box (I had no idea of that as I never saw the car running before). They all seem in a very good condition, so I can reassemble everything as is (if there wasn't that bead / sand issue :banghead: )

#10 Re: Needle bearing for clutch fork shaft?

Posted: Mon Aug 18, 2025 11:11 am
by rfs1957
From painful past experience I can tell you that bead-blasting residue can cause appalling damage, and I find that many people who use the method completely misunderstand the scale of the threat.

As an example, we would consider sand-cast Ducati crank-cases as things that should NEVER be bead-blasted, since you can never be 100pc sure that you get it all out.

Hot parts-washers, steam-cleaning, you can do what you like, at some point there’s a risk that some has got hidden and will escape later.

Even on die-cast stuff you can take nothing for granted.

Maybe that’s why soda-blasting got invented.

#11 Re: Needle bearing for clutch fork shaft?

Posted: Mon Aug 18, 2025 4:07 pm
by Philippe-J.
I am painfully realizing what a poison it is, believe me :questionmarks: .
I think that painting the inside of the casing with that orange paint would help to get closer to the 100% sure.
After brushing, and compressed air, and again and again. :fingerscrossed:

#12 Re: Needle bearing for clutch fork shaft?

Posted: Tue Aug 19, 2025 5:11 am
by Boris64
Philippe,
Tu peux mettre les pièces au lave vaisselle, ça éliminera bon nombre de grains de sable…

#13 Re: Needle bearing for clutch fork shaft?

Posted: Tue Aug 19, 2025 6:43 am
by Philippe-J.
Boris,

dishwasher? Interesting! Even the steel gears and shafts? Won't they rust?

Philippe

#14 Re: Needle bearing for clutch fork shaft?

Posted: Tue Aug 19, 2025 9:41 am
by Boris64
Yes, but without any product…

#15 Re: Needle bearing for clutch fork shaft?

Posted: Tue Aug 19, 2025 4:35 pm
by tim wood
Using the dishwasher !
That’s got me in trouble more than once !!!!!

#16 Re: Needle bearing for clutch fork shaft?

Posted: Tue Aug 19, 2025 4:37 pm
by Boris64
With your wife ?😄