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Gallery, Projects and General => Gallery => Topic started by: AdeV on May 28, 2011, 07:13:06 AM

Title: Another job off the list
Post by: AdeV on May 28, 2011, 07:13:06 AM
I'd been asked to turn down a motorbike triple tree (aka triple clamp or yoke), so a supplied bearing would fit on it. After much head-scratching, it was determined that a faceplate would be the most obvious option.

Of course... obvious != easy; it took a good 3 hours of tapping and adjusting to get the tube centered & running true. There must be an easier way...

Here it is mounted on the faceplate:
(http://lister-engine.com/pics/TT_1.jpg)

I used the mill clamping kit to hold it; the shims are necessary to make the tube run true (another  :thumbup: to Bogs, who gave me the brass shim stock that happened to be exactly the right size). I've already taken the first few cuts in the above pic. Because access was such a pain (the steering lock "bumps" on the yoke seriously impeded tool access), I ended up using the very edge of a Mircona parting tool:

(http://lister-engine.com/pics/TT_2.jpg)

Small, slow cuts were the order of the day. I gradually whittled down the main diameter until the bearing was an easy slide fit down the majority of the tube; the goal was to make the last 20mm (the width of the bearing) a reasonably tight push-fit. In the event, I got it down to that level, but the final cut just ended up a touch over; so whilst the bearing sat nicely, it didn't grip properly. A smear of Loctite was therefore employed to keep the bearing in place. Normally, of course, it'll be squashed up against the cup with a hefty bolt, so in theory the loctite is unnecessary.

The finished article:
(http://lister-engine.com/pics/TT_3.jpg)

I did get a little chattering on the final cuts, hence the slightly sub-standard surface finish; but this'll all be hidden away in a tube anyway, so it's no big deal.
Title: Re: Another job off the list
Post by: Rob.Wilson on May 28, 2011, 07:26:08 AM
Hi Ade


Would the spindle not just press out from the bottom yoke  :scratch:     ,,,,,,,,, all the ones i have done do     :)



Rob
Title: Re: Another job off the list
Post by: AdeV on May 28, 2011, 12:10:21 PM
Hi Rob - unfortunately, it'd been welded in; and I didn't fancy breaking the weld & re-doing it, my welding isn't that good yet.... and this is a bit of a critical component...
Title: Re: Another job off the list
Post by: Brass_Machine on May 28, 2011, 10:29:55 PM
Would the spindle not just press out from the bottom yoke  :scratch:     ,,,,,,,,, all the ones i have done do     :)

Some are welded, some are press and some are even screwed in. I am using a set of Ducati triples on a Honda. Those have a screw in stem so it was just a matter of machining a new stem to fit the Honda neck and bearings.

Eric
Title: Re: Another job off the list
Post by: Rob.Wilson on May 29, 2011, 04:46:33 AM
That would explain It Ade  :doh:

lt looked like an ally bottom yoke  ::)


Rob  :)
Title: Re: Another job off the list
Post by: AdeV on May 29, 2011, 07:05:06 AM
It does look like Ali, you're right; but I'm pretty sure it must be galvanised steel because it's too heavy for Ali.
Title: Re: Another job off the list
Post by: bp on May 30, 2011, 12:48:16 AM
Probable material is steel, with silver paint finish.  Norton Commandos had steel (malleable I think but I'm not sure) yokes, which replaced the very expensive cast ones used on a featherbed frame.  Anyway, the "old" way was to braze the steering head stem into the yoke, the "new" way suggested by the man from Loctite was to use......ummmm.....Loctite.  There was a lot of tooth sucking from the elders, so a test piece, or pieces were made.  The only way to get the stem out of the yoke after Loctiting was with a very big press, and some of the parent material from the yoke was still attached to the stem!!
cheers
Bill Pudney