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...how dodgy is running 1.2mm (ish) washers between my direct mount stem and the top crown of my 40's?
Needed about 1mm extra of clearance to run my bars at the 45mm stem setting (35mm easton bars which foul the adjusters on the top of the stantions at 45mm stem length). The top crown already has a 10mm spacer under it (which is a little more than I would like) but I don't have any more stantion to run another 1mm of spacer under the crown.
Now my initial thought was that this was a silly idea however lots of people use these:
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I was thinking that was ok because of the amount of contact area.
However looking at the new style Fox 40 top crown the only area of contact between the DM stem and the top crown is the small raised area around the bolt hole in the crown as the rest is machined away. Thusly:
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So effectively if I use a washer it's still the same amount of contact area. The bolts as far as I can tell thread in the recommend min. 10mm in to the crown.
Pretty sure in during writing this post I've convinced myself it's safe. Please feel free to tell me otherwise.
Mechanically I can't see how it's unsafe, but there are a couple of caveats:
1. It'll probably creak like crazy.
2. The washers may - may - damage either the crown of the forks or the stem over time.
Go for it and report back if you survive.
I would run it.
1
are they 650b Fox 40's if so it will be fine, 26" and it's more backwards in a fireball entry to Valhalla than driving a TVR in a monsoon.
or it looks like it will be fine, make sure you get matching washers.
Afraid it's 26" on my 26" V10. So obviously I'm no longer cool and the bike is probably going to magically implode due to the wheel size being so last season.
Had already bolted it up. 4 equally identical washers. If it creaks I doubt i'll hear it over the noise of me clattering blindly through everything in my way. Apparently there is something called 'line choice' but I find with 10" of rear wheel travel 'point and hope' covers most of it 😛
If I die as a result of this I'll be sure to let you all know.
Strength is in the bolts, not the surface/ contact area. Might need longer bolts though?
Yeah I thought that the current ones 'should' be long enough but just in case it might have been my justification for ordering new bolts. Then I got carried away and ordered enough Ti bolts and washers to do the whole bike...