Safetywire front caliper bolts?

[battlecry]

How do you safetywire the front caliper bolts on Marzocchi forks?  The top bolt is buried in the fork. 

Do you grind some of the fork material away?  Do you use a longer bolt with thick washers under it to raise the head? 

It seems to me either way you lose some strength.   What is the preferred method?

[Speeddog]

I'd say longer bolt with a thick washer.

Make sure the washer is a *good* fit, not so large in diameter that it hangs up on the corner of the counterbored hole.

I'm assuming you need to safetywire them for racing?

[battlecry]

Yes, Speeddog, doing a track day.  Snowing now, so it is a good time to prep the bike.  Safetywired the rear rotor, rear caliper, rear master, banjos, front banjo, rear axle nut and chain adjusters, fork pinch bolts, oil filter and filler cap, front sprocket.  Want to do the front calipers and banjos, the front axle nut and the exhaust springs and hangers, the ones with the blue insulators.  Not clear if they will require the rest of the exhaust, i.e. header nuts and can hangers.  Figure will call them and ask them.   

Thanks for the advice, I'll break open the MacMaster-Carr catalog and look for some new bolts.

[Speeddog]

Do they require all that for a trackday?

I've only done two trackdays, and they were a while ago, but about all they did was look at my tires to make sure they weren't showing cord and squeeze my front brake to make sure it worked...

[battlecry]

Beats me.  The ART guys seem pretty relaxed, so maybe it will just be a blue tape affair.  I looked at the MARRC bike prep guide for ideas, and since there is a whole lot of white stuff outside, I figured I'd go for it.  Had no idea how easy it was to break all those 1/16" bits...

[Speeddog]

Get a couple center drills, a lot easier to get the hole started with those.

[battlecry]

Thanks, didn't know they made them that small.  I break them mostly when they punch the other side.  The hardened surface and uneven torque breaks them right off.  Now I drill until the surface at the other end dimples then stop and move on to the next bolt.  When I get most of the bolts done, I go back and very gently finish the holes. 

[Speeddog]

Center drill won't help breakage when the drill goes through, but saves you on the starting bit.

Your technique is good for when the hole goes through. 

[Spidey]

Every bolt I've had to safetywire that was recessed has been drilled so that the outer hole is right by the top of the head of the bolt.  You don't have to drill them from middle of the head of the bolt across the diameter to the middle of the head of the bolt.  Just drill a single hole starting from the outside of the head and near the top.  Then drill through the head of the bolt at an angle down toward the axis of the bolt.  Then you can take your safetywire and make a little fishhook with the end and go from inside the head of the bolt to outside.  Then pull it through the outside with a pair of needlenose pliers.

Gawd, that didn't make any sense.  Lemme see if I can Paint a diagram.  

Edit:  welp, looks like my Paint skills are even worse than my ability to explain.

[DarkStaR]

How about a tapered head bolt?

[Speeddog]

~~~snip~~~ 

Edit:  welp, looks like my Paint skills are even worse than my ability to explain.

Nah, that made pretty good sense.
At least to me, but maybe if someone has no idea of what's going on, it might not make sense.

I've drilled hex head bolts just with a center drill, in from the side on a flat, and then down from the top.

Here's a couple of decent how-to's on safety wiring:
http://www.jalopyjournal.com/forum/showthread.php?t=215935
http://www.avweb.com/news/maint/191176-1.html

This has a decent description of one way to drill a bolt, but *please* do not wire like they've shown.
http://volvospeed.com/Mods/safety_wire.html

[coll0412]

If it is a socket head cap screw then just grind a corner of the cap to provide enough clearance for the wire to come out. Then drill the hole at an angle as show above. This is how it is done on my race 03' M620.

[Ducnial]

Be sure to take some pictures when your done,  and during tech..

[wantingaduc]

I have another suggestion.

I was looking to do my 620 this winter in advance of a spring track day too and I was thinking that in the case of those bolts I would drill a hole through the mounting tab on the fort leg and into the bolt head at the same time.

Imagine looking at the bike from the front, drill through the metal that surrounds the bolt from there and through the bolt head together and then just wire it in place.

The idea is to secure the head of the bolt to a stationary object and that metal mount couldnt be more stationary. Then you wont need to wire the 2 bolt heads together either.

And please post up pictures of how you wind up wiring them.

jimi

[DarkStaR]

Good luck getting the holes to align the next time you work on the front end.

I have another suggestion.

I was looking to do my 620 this winter in advance of a spring track day too and I was thinking that in the case of those bolts I would drill a hole through the mounting tab on the fort leg and into the bolt head at the same time.

Imagine looking at the bike from the front, drill through the metal that surrounds the bolt from there and through the bolt head together and then just wire it in place.

The idea is to secure the head of the bolt to a stationary object and that metal mount couldnt be more stationary. Then you wont need to wire the 2 bolt heads together either.

And please post up pictures of how you wind up wiring them.

jimi