Paint or polish?

[Ricco1]

I have an old Yam RS125 that I ride daily while I do it up. The crankcase covers are in a bit of a mess. Brush painted by the previous owner, the paint is flaking off in places.

Polishing might be the easiest way to go, could do it without the pain of removing the covers. I'm aware that once polished they need a lot of maintenance so because of this, I'm leaning towards paint. Couple of questions:

1/ I'd need to wire wool the cases to get the old paint off, I'd be painting raw alloy. Do I need a primer coat, any recommendations?

2/ Do I need to use 'engine silver' for the final coat, or is the temperature of covers low enough to make normal silver spray paint ok? Any recommendations for paint?

Cheers.

[rennie]

Have you priced up new ones?

It might be quicker/cheaper/easier!

[Ricco1]

It's a 1982 bike. The only ones I've seen for sale have been far more battered and bruised than mine!

[rennie]

can't you get "new" pattern parts?

[oldgrump]

Hi Mate, Cheaper to spray them, any good engine case paint will do, I use PJ1 for black, and Simoniz VHT for silver, just wirewool old paint off, then see if you can find some paint degreaser, which you wipe casings over with before spraying.

Couple of light mist coats first and then apply heavier coats, but leave to cure between coats. One can at 500ml should be enough to do your engine.

Good thing about the RS125 is you can get the engine out of frame in about 15 mins, so you can clean casings on the bench. take it you doing main casings as well or just the 4 outside ones?

Price for the 4 outside ones NEW would be about £200 + gaskets. but I think 1 casing now obsolete.

[Ricco1]

The plan is to do the outside casings as the inner covers are in decent condition. There will more than likely be a colour difference but I'm not bothered about that. I'll leave the engine in the frame and remove the covers. Just need to get the confidence to take the right side one off, as I'll need to bleed the oil pump when I put it back together, don't want to make a mistake with that.

[oldgrump]

Hi, if you're taken casings off, don't forget to get a new gasket for r/h casing, and I know you got the oil seal in r/h case for oil pump drive, but have you got anyone near you who's got a shot blast cabinet, then you could shot blast/bead blast casings, save you a lot of time, then spray them. And thinking about it the 125 only had 3 outside casing? 100's had 4.