First job strip the back of the bike. It looks complicated but really quite straightforward.
1 Remove battery, all plastics and bolt-ons. Put everything into small freezer bags
2 Disconnect brakes at the junction piece above the swing arm Ive put suitable bags over the pipe ends.
3 Remove air box. This means taking off the throttle cable splitter and possibly RHS throttle body if the cable is too short.
4 Take off swing arm complete with FD. Haynes manual shows how though you can remove the RHS trunion by knocking through from LHS with a long rod.
5 Remove the four M10 bolts holding rear subframe to engine.
6 Take off all plastic clips and widgets use photos for reference. Dont forget the plastic bushes where the gear shift lever runs. New bushes are £5 a pair from BMW.
7 The various brackets all have one side which is relatively sharp cornered. This enough to thin any coating allowing new corrosion to begin. File all edges smooth. Be fussy, the ones you miss could are more likely to cause trouble in years to come.
8 Put suitable bolts into every threaded hole. Leave the back side just proud so the coating wont clog the thread. Use a bolt long enough for its head to not shade that side of the hole.
Dont bother to protect the centre stand bolt holes. The countersinks will be difficult to mask and its not a precision fit.
9 Heat the area around the colour chart sticker with a hot air gun and carefully peel off the frame. Stick it onto some suitable non-stick backing paper
10 Ask coating company to protect all exposed threads and fitted sleeves such as swing arm bushes.
11 Ask for a chemical dip and shot blast. If its all being shot blasted only, they need to take extra care to protect anywhere that bearings have to fit. If its got the older tough paint it might have to be chemical dipped.
12 Pre-coat with zinc primer. This can be whatever system the coating company use, but you need a zinc-rich base layer. You could even consider electro plating (not hot dip!). Zinc isnt "that" costly but ask the powder coaters if their product works over zinc. If you go that way you might want to consider etch primer over the zinc plate and paint.
13 Finish coat in whatever colour you fancy
14 Protect new frame with bubble wrap
15 Back home take out the protective bolts and clean the holes as needed. Any taped over areas will need solvent to clean off the protective tape glue.
16 Put all the clips etc back
17 Stick the colour chart sticker back on the frame
18 Replace swing arm bearings. Order the correct type (how would I know that?)
19 Rebuild bike. If using stainless washers, fit the rounded side towards the paint because the sharper edge can fret though the new finish.
20 Make a sideboard ornament with left over parts.
Comment on step 11 - The finish used on alloy parts is extremely tough but one damaged, corrosion can run a long way underneath. This has to be chemical dipped - too tough for grit blast removal. The frame paint isnt so tough and the steel is harder than aluminium alloy, so can probably be blast stripped only.
Overall comment.
Choose your coating company carefully. The big commercial outfits will produce a good looking job, but might not be so fussy about fully blast cleaning every nook & cranny. I now use Wing & Son near Totnes Devon. I used to use CJ Ward of Burton on Trent. The latter are more industrial finishers but they really do understand bikes.
Hope this helps
Dave
