EddieStone wrote:Warkton Tornado No.1 wrote:If you intend to salvage the hub, beware of drilling deeper, but you could repair the holes.
As M7 is just a slightly bigger version of common M6 x 1.0, you can usually Helicoil a stripped M7 'down' to M6 with a kit.
It might sound a bit crazy but was something I've done in the past when I couldn't acquire any quality high tensile fasteners elsewhere on a Lambretta.
With any rear hub extraction, though, you should fit the longest, good quality fasteners that will fit almost the full depth of the hole without bottoming out that ensure the extractor tool is clamped into place, tighten the centre bolt & give it a knock with a hammer.
I hope that helps.
Did this and it worked a treat.
Thanks!
Thank you for the positive feedback! I've been bedridden since Sunday, missing Wickstead's & other important events (sorry Martin!) but you've cheered me up!
EddieStone wrote:Turns out the endplate was loose. Didn't have to take the hub off after all.
I've never had this ever before. Any idea what causes it and how to prevent it? Apart from doing the nuts up tight, of course
Any time I have a block to rebuild, I always remove the existing M7 x 1.0 studs & run a tap down the holes to clean out the threads. Next, a cotton bud with Meths (Hic!) or thinners down the holes. Then, I select the longest, scrupulously clean ENGINEERS studs (strong, ‘rolled threads’ type) that will fit & Loctite them in place VERY CAREFULLY with just a nat’s of Studlok so that I don’t ‘hydraulic’ the studs causing breakage of the casing. If I have any doubts, I Helicoil the holes back to M7 (now that I have the kit!)
I use fresh, ‘proper‘ stout, black hardened M7 spring washers & hardened, high tensile M7 nuts & torque up sequentially to about 12.5 lb/ft*. No Loctite on the nuts, just squeaky clean.
If you are prepared to Helicoil all six holes, M7 SHCS’s (Socket Head Cap Screws) can be utilised. Again, select the longest that will fit/be prepared to cut down screws that are too long. Use only a low strength Loctite in such instances if compelled to do soIncidentally, when checking the endplate float (with the layshaft fully tensioned via the hub nut) it can be made less tedious by leaving the gear cluster out until the desired clearance (0.003” – 0.011”) has been achieved, not forgetting to finally fit the cluster @ the end....
I hope this helps as it is an area where you cannot compromise.
*
That torque figure is for threads in perfect condition & if there is any doubt, use less force.