damaged screw heads- help!

Being an SV, with bolts made of Dairylea, I have a couple of screw heads that have crumbled under my efforts to remove them from the bike.

One is a chain guard screw- I've tried filing a slot to get a wide flat head screwdriver onto it, but to no avail- though this is ongoing. The screw head seems well solid against a file, but not a screwdriver!!

Also, the screw on the rear choke plunger assembly has done the same. (apparently, these are ?11 a pop...)

So- not having to have dealt with this much in the past, I'm not really equipped to sort this out myself and haven't got a clue how to/don't want to cause more damage (esp. to the carbs!)

Before I panic and hand the bike over to a mechanic and sort the problem (at ?47/hour), are there any tools/techniques that will help me deal with this in the future?

[G]

You can with a very very steady havd drill them out.

Failing that you can also buy reverse screws, you basically drill a 1/2mm pilot hole then use a resverse screw to drill into the offending screw, as its going in reverse it locks on the offending screw and screws it out ( I have rarely ever been able to get this technique to work.....you can buy them in halfords)

[jambo]

The screw on the carb choke plunger's a bit of a git for doing that. Apparently you can use a set of mole grips to crush it slightly and turn it with them, as access to the side should be ok. I have also had some success drilling the head off it as the thread was fine, it had seized to the plate behind it.

Cheers folks- reverse thread screw- GENIUS!

So long as you've not completely rounded the screw heads, you could try using a hammer with your screwdriver and "shock" them out?

You will of course need to be careful with the choke plunger screw, but it should be do-able. Plus if that doesn't work, you can always then try the reverse thread jobbers or some easy outs.

Sorry to hear about your latest bit of bovver

In my Factory pro jet kit they included new allen bolts for the chokes and the tops of the carbs. well worth replacing with something similar and not 11 quid cr@p ones.

Good luck

[johnnyrod]

Dunno about the swinging arm one but I had the same thing on the choke plunger. Get a largish flat screwdriver and put it on the edge of the screw head and tap it with a hammer. You want it so it's tangential and obviously tapping to try to turn the thing anitclockwise. You might need to make a notch first with a cold chisel so the screwdriver doesn't slip off too easily but a few taps should free it up.

Originally Posted by thedonal

Cheers folks- reverse thread screw- GENIUS!

I would leave this as a last resort!

Use some plus gas or something to lose the screw a bit. A wide screw driver (wider than the grove) press on it hard and tap with a hammer (could do both directions to lose it). Works for me every time.

plus one for molegrips...

[jambo]

Be very careful of using any shock treatment on the chainguard bolt. It's a fairly thin tab of ally that it goes through and snapping it off the swingarm would be a bit of a sod...


Jambo