Power Valve Couplers

[krmiller70]

Hello,

Does anyone know if there is a vendor either on this forum or in general, that makes an aluminum coupler to replace the stock plastic piece? This coupler connects both p/v's between the cylinders to ensure they both open at the same time!

Thanks in advance.

Krmiller70

[evan_calgary]

I don't believe these were ever plastic. Every one I have seen was made of metal (steel or aluminum). I have one sitting around if you are in need.

[T.RexRacing]

Nope never plastic. And still available from Yamaha new.

[krmiller70]

That's good to know. I was told Yamaha lists these as NLA. Are you guys located in Canada?

[krmiller70]

I don't believe these were ever plastic. Every one I have seen was made of metal (steel or aluminum). I have one sitting around if you are in need.

How much would you want for yours? And what kind of shape is it in?

Thanks

[silverstrom]

They're not NLA in Canada, so they shouldn't be NLA in the US.

[JonW]

Not NLA OEM, and yes there is an aftermarket which is nicer, Wicked makes an alloy one.

[krmiller70]

Not NLA OEM, and yes there is an aftermarket which is nicer, Wicked makes an alloy one.

Thanks Jon,

I thought I saw one and was pretty sure he made them. If he had a functional web site... Hear that Rodger! Lol

[T.RexRacing]

He isn't all that interested in the RZ market anymore.

[krmiller70]

Too bad. He builds and makes some high quality stuff !

[JonW]

He is interested, hes just busy. Ring him and he'll sell you a coupler.

[Hooligan]

When looking for parts, best thing is to Google it by the part number. Its amazing what is out there.

Boats.net has a ton of stuff as does RonAyers.

Not super cheap but def available. $40 for the pair

http://www.boats.net/parts/detail/yamah ... 00-00.html

http://www.boats.net/parts/detail/yamah ... 00-00.html

[silverstrom]

Yamaha still sells both parts and they aren't expensive.

The stock parts will last forever if you look after your valves. If the coupler is badly worn it comes down to poor maintenance that causes the valve ends to wear or improper installation of the coupler.

Or, get rid of the coupler and do the 4 cable mod.

[Hooligan]

It has occurred to me that bedding the valve ends into the coupler using Devcon would be a good idea. A bit of wax on the valve ends stops them sticking to the Devcon.

[silverstrom]

It has occurred to me that bedding the valve ends into the coupler using Devcon would be a good idea. A bit of wax on the valve ends stops them sticking to the Devcon.

The simpler solution is to file the new OEM couple halves lightly to ensure a good clamping force. Just a little off both halves and then ensure your cylinder and valve alignment is good and the vales are moving freely and no more problems.

It seems that when installing cylinders many people do not check valve alignment before torqueing the base nuts. As you know, there is quite a bit of movement where the cylinders meet the cases. Better dowelling by Yamaha would have prevented that. Before torqueing the base nuts ensure the cylinder alignment is perfect. That goes a long way toward ensuring proper valve alignment and operation. Properly serviced valves and good bushings and retainers will make the center coupler last forever. Improper alignment and filthy valves will result in the valve ends being worn and damaged and at that point no coupler will help you.

I'm not against the fancy expensive billet valve couplers, but if the rest isn't right the bigger coupler is just covering up the problem. When everything is properly installed you should be able to turn both valves at the pulley with 2 fingers and it should be easy to do. If you can't, it isn't right.

Curiously, TZRs and RZ500s use the same type of coupler and we don't hear about problems there.