Removing the Throttle Bodies

[Bixxer Bob]

No big deal with this one, (forgot to take photos again   ) just take your time.

Take off your tank and airbox as described elsewhere, disconnect the throttle cable, remove the IACV and tubes, disconnect the ign coil wiring and lift it out of the way.

Undo the 6 retaining screws.  I'd recommend replacing these with allen bolts; they're 30mm to the underside of the head with at least 10mm thread, 6mm dia standard pitch.  To remove them I found putting a torx bit in a 1/4 drive socket with 8" extension easiest as they are a bit of a b**** to get at.  The lower left hand one needs the bit putting in place from underneath and then the extension pushing down from above as the socket won't go through the space available.

Give them a sharp knock with the palm of your hand and they'll break free.  You can lift them far enough out of the way to do the gasket without further dismantling.

Now for the does and don'ts:

DO:  

1. Remove all of the the old gasket.
2. Roll up some gaffer tape, sticky side out and put it down the cylinder head intakes so the whole hole is filled, but don't compact it!!!  This will stop any bits of grit or gasket getting into the engine.

DON'T

1. Scrape the gasket off with anything metal unless you really know what you're doing.  You could score the surface and cause an airleak.  Even though I consider myself competent to use a scraper, I found the alloy to be particularly soft so made a scraper out of a piece of perspex.  As long as it's got a straight clean cut edge it'll do the job nicely.
2. When scraping, go round the port rather than across it, that way, even if you do screw up, you'll mark it in line with the port wall rather than cutting an airway across it.
3. Forget to do both surfaces, the cylinder head and the throttle bodies.
4. Forget to remove the gaffer tape carefully so you don't drop anything down the ports.
5. Forget to re-adjust the throttle cable properly after re-fitting it.

I used a silicone gasket goo made by Loctite which contains copper as well as using the gasket.  If you do the same, make sure you don't get it down the intakes.  I only applied a thin smear so it was ok.  Check by opening the throttle butterflies and having a look.

[Stretch]

Linked to 'Wisdom'.  Thanks for the write-up.