Mikuni throttle valve (slide) coating damage, need advice

[Nicholas]

Hi all,
I’ve just gone and damaged the golden coating on my throttle valves by cleaning them in a hot ultrasonic cleaner.

They were in very good condition prior, and now there are scores in the coating and its come off in places.

Does anyone know if I can repair them or should I get replacements? I have looked online for replacements and most seem to be chrome plated and not like mine, gold. I have can get a used set, but I guess I would check to see if they can be repaired.

They came off my Suzuki GT500 that was fitted with a VM32SC and all 188 Series parts. The throttle valve was 2.5.

I have included some pictures of the damage.

[tz375]

If they are smooth, I'd just run the ones you have. Chrome slides are brass and plated. Gold colored slides are Al and are anodized. You should be able to find replacements if you really have to.

[Nicholas]

If they are smooth, I'd just run the ones you have. Chrome slides are brass and plated. Gold colored slides are Al and are anodized. You should be able to find replacements if you really have to.

Ok thanks, I wasn't sure what they were, and found some people commenting on other forums that they were Teflon coated...so I assumed it was that as the surface had a kind of plastic feel to it... They said their idle and throttle response was affected when the coating was damaged. I thought about re-coating them, but then you need to know how much so I decided to buy a set of used ones from Marcel.

I've just put the engine back into the frame today, and chamfered my piston skirts...will put the head back on tomorrow and fit the new alternator and setup the timing...just need to get my seat covered and I need to do my electrics and my bike will finally be back on the road!

Hope my custom oil lines hold up!

[tz375]

When you say "chamfered the piston skirts", what exactly do you mean by that? I know what it means in general did you chamfer the inner or outer surface?

[Nicholas]

This..